News Category: Knee

Patellofemoral pain syndrome (PFPS) affects one of every four young athletes. Pain along the front of the knee with activities like squatting, running, sitting for long periods of time, and going up and down stairs is common. The condition is so common in runners that it is often called runner’s knee.

Physical therapists and sports physicians are actively seeking ways to help treat this problem. The goals of treatment are to reduce pain, decrease swelling, and restore function by improving strength and joint motion.

These goals are accomplished in one of two ways: conservative (nonoperative) care and surgery. Of course, the conservative approach is recommended first. The physical therapist uses a variety of techniques to assist the patient with patellofemoral pain syndrome (PFPS).

Tools (also referred to as modalities) are used such as cold or heat therapy, electrical therapy, and biofeedback. Each of these modalities provides several options to choose from.

For example, therapeutic heat to increase blood circulation and stimulate healing can be applied using ultrasound, moist hot packs, and whirlpool. Electrical stimulation (e.g., transcutaneous electrical nerve stimulation, neuromuscular electrical stimulation) helps control swelling and encourages muscle contraction. Other modalities used to reduce pain and inflammation can include laser, ultrasound, and phonophoresis/iontophoresis.

But how well do these modalities work? Which one is best for each patient? Should they be used alone or is there some combination of two or more that yield the most optimal outcomes? To be honest, we don’t really know.

That’s why the authors of this study carried out a review of all the studies published on the use of modalities for patellofemoral pain syndrome. They searched all computer databases available from 1970 to 2010 looking for full articles in peer-reviewed journals on the use of therapeutic modalities in the treatment of this condition.

They found 12 studies that fit the required standards but most of these were low-to-moderate quality. None of them were able to show a positive benefit in the treatment of patellofemoral pain syndrome when used without other treatment as well (such as taping, exercises, surgery, bracing).

The authors provided a detailed four-page table comparing each study based on the intervention (modality or combination of modalities used), outcomes measured, and statistical results. The studies did not all evaluate and measure results in the same way so there wasn’t a direct item-by-item comparison possible.

For example, some (but not all) studies measured isometric muscle strength. Even when isometric muscle strength was the outcome measure used by more than one study, different muscles were evaluated (i.e., they didn’t all measure the same muscles).

Some researchers used specific tests such as a step test or squat knee test to look for muscle fatigue and endurance. Others used reliable and validated tests (e.g., Lysholm Knee Scoring, Kujala patellofemoral score, Functional Index, Patellofemoral Pain syndrome Severity Scale) to assess pain, edema, and/or daily activities.

The number of treatments per week and number of weeks treatment was administered also varied from study to study. This could be an important variable accounting for differences in results from one group to another.

Taking a look at several specific modalities, laser compared with a sham (pretend) laser had no difference in results. But there are dozens of considerations when studying laser: wavelength used, power density, length of time laser is used (duration of treatment), how long between injury and treatment, and so on.

EMG biofeedback seemed to work best when combined with exercise in the short-term. But long-term results didn’t show a difference. And biofeedback was combined with taping of the patella so there is a combination of two treatments that couldn’t be separated out.

In the end, there simply wasn’t enough scientific evidence to support the solo or combination use of modalities mentioned. This may be the first study to make such comparisons and bring this information to our attention.

There’s no doubt that sorting out which modalities might be useful and in combination with what other treatment options (in terms of modality use) is a challenge. If there is no added benefit of using such modalities, then they should be discontinued. With so many variables yet to study, it’s clear that future research in this area is needed.

Physical therapists often use elastic bands to give resistance to muscles during strength training programs. The bands come in different colors. Each color signifies the strength of the resistance starting with yellow (mild resistance) and going up from yellow to red to blue, green, and black (greatest resistance).

Recently, a physical therapist from the Department of Kinesiology at Louisiana State University took the time to review studies using elastic resistance to treat patellofemoral pain syndrome (PFPS). The goal was to look for and report on any evidence that this method of treating PFPS is effective.

Patellofemoral pain syndrome (PFPS) affects one of every four young athletes. Pain along the front of the knee with activities like squatting, running, sitting for long periods of time, and going up and down stairs is common. The condition is so common in runners that it is often called runner’s knee.

Physical therapists and sports physicians are actively seeking ways to help treat this problem. The goals of treatment are to reduce pain, decrease swelling, and restore function by improving strength and joint motion.

Elastic bands are used to strengthen hip and knee muscles that are weak or imbalanced. A strengthening program is part of the rehab program for PFPS because previous studies have shown that muscle weakness is one of the main reasons why young athletes develop this problem. Women are more likely to develop PFPS than men — probably because of anatomic differences in alignment of the pelvis, hip, and knee.

The author searched three of the largest and best known research databases for studies evaluating the use of elastic resistance bands for PFPS. He found eight studies that met the criteria for inclusion. The studies had to be peer-reviewed. Peer-reviewed means the studies were examined carefully by others within the profession before being accepted for publication.

Patients had to be in the research study a minimum of four weeks. And, of course, elastic resistance bands had to be used in a muscle strengthening program. Seven of the studies had 20 or more patients enrolled.

Seven of the studies were considered randomized prospective. This means that patients were randomly placed in a treatment group and the study was done as the patients participated in the program. One study was retrospective in design — that means the researchers looked back at results after the study was over.

Results did show that using elastic resistance bands improves muscle strength. But the significance of this finding for patellofemoral pain syndrome (PFPS) was lost by the fact that the studies were poorly designed. For example, there are ways to predict how many people must be in a study for the results to be meaningful. That concept is called adequate power. Only three of the seven studies were adequately powered (i.e., had enough people in the study to generate statistically significant meaning).

This study was an effort to find alternative treatments for painful knee osteoarthritis. The authors used radiofrequency (heat treatment) to kill three small branches of the sensory nerves to the knee (genicular nerves). The procedure is called a radiofrequency neurotomy.

The 38 patients in the study had severe knee pain from osteoarthritis. The painful symptoms had been present for at least three months, which makes it chronic pain by definition. They had all tried (and failed) to get relief with conservative care.

Everyone in the study did get relief from a diagnostic nerve block (injection of numbing agent into or near the nerve). Nerve blocks are used to confirm that nerve irritation is the problem and source of pain. But a nerve block only provides temporary effects. Once the pain came back, then this study with radiofrequency ablation was done to end painful symptoms permanently.

Half the patients received a true radiofrequency treatment to three branches of the genicular nerve. The surgeon creates a tiny tunnel through the skin and soft tissues down to the bone. Fluoroscopy (real-time X-rays) and sensory stimulation were used to make sure the surgeon was close enough to the nerve to make accurate contact.

After the nerve was located then a radiofrequency probe was passed through the tunnel to the nerve. The tip of the electrode was heated up to 70 degrees Celsius (about 160 degree Fahrenheit) for 90 seconds. This ensures that the nerve is destroyed and no further pain transmission can get through.

Cutting the nerve supply to the joint is meant to reduce pain and thereby restore joint motion and function. The other half (control group) got the same procedure but without a true neurotomy being done. The radiofrequency probe was advanced through the skin to the nerve but no heat was applied to the area.

The treatment was considered a success if the patient got at least 50 per cent improvement in pain for more than a 24-hour period. Anything less than those criteria were considered a failed treatment. Additionally, before and after (at one, four, and 12 weeks after the procedure) measurements of pain and function were recorded.

The results showed a significant improvement in pain one week after the procedure for both groups. But only the radiofrequency (RF) group maintained pain relief and improved function at the rest of the follow-up appointments. Patients in the RF group were much more satisfied with their treatment results when compared with the control group.

The authors suggest that radiofrequency treatment for painful knee osteoarthritis is a possible treatment choice. It is safe and effective. But because it is an invasive procedure, other conservative approaches should be tried first. A diagnostic nerve block should also be done before using radiofrequency ablation.

There are times when the RF treatment is not successful. This is most likely because the target nerves vary in their anatomic location. And sometimes there are extra branches that still supply the joint with nerve impulses.

Pain is relieved only if and when all branches of the sensory nerves to the knee are found and destroyed. If the first procedure doesn’t completely eliminate the pain, neurotomy can be repeated a second and even third time.

Further studies are needed to see how patients fare months to years later. Does radiofrequency ablation speed up osteoarthritic changes? Does it slow down degenerative changes? Are there adverse effects that only become apparent much later after the procedure? More evidence is needed before final conclusions and recommendations can be made.

The timeline currently used for athletes after anterior cruciate ligament (ACL) surgery goes something like this. Rehab and recovery after surgery takes a good four to six months for everyone. Sports specific training is designed to return athletes to their sport by the end of a year’s time.

But can they participate at their preinjury level? Are most athletes really back on the field, court, or track by the end of 12 months? That’s what this study was all about. It was conducted at the Musculoskeletal Research Centre at the La Trobe University in Australia.

The researchers took a look at data collected on over 500 competitive athletes who had surgery to reconstruct a torn anterior cruciate ligament (ACL). One surgeon did all of the surgeries. All patients included in the study had the procedure done arthroscopically with a single-incision. The tendon graft used was taken from the patient’s hamstring muscle (tendon). The harvested tendon tissue was looped over to form a quadruple-strand graft.

The goal of surgery was to restore joint stability. In practical terms, this means getting the athlete back to activities that involve jumping, pivoting, and cutting. In this study, patients were Australian football, basketball, netball, or soccer players.

They also analyzed the results to see if there were any specific factors that could predict who would do well and how soon athletes did, indeed, return to their sports participation.

Some of the items reviewed included 1) whether the athlete was engaged in seasonal versus year-round sports, 2) how soon the surgery was done after the injury, and 3) whether sex (male versus female) made a difference. In other words, were men or women more likely to return-to-sports before the end of the first year?

Patients were contacted after the end of a full 12-months following surgery. They were asked if they had returned-to-sport (or attempted to return) and their current playing status. If they had not yet returned-to-sport, they were asked why not and if they intended to return (and how soon).

Specific tests of knee function were also performed and results compared from before surgery to after surgery. Two of the tests used included the Cincinnati Sports Activity Scale (SAS) and the International Knee Documentation Committee (IKDC) evaluation.

Two thirds of the 503 athletes had not attempted participating fully in competitive sports at the time of follow-up. About half of those 335 athletes had attempted training and/or modified competition. Most of these folks were male. The other half (some men but mostly women) had made no attempt at sports activity.

Some patients had given up because of the knee problems. An equal number gave up sports for other reasons. A large number (159 patients — an equal number of men and women) still planned to return to competitive sports but 84 had no intention of doing so.

Taking a look at the test scores, it was clear that about half of the patients (48 per cent) had normal knees. The other half (actually 45 per cent) had nearly normal knees. The remaining seven per cent had abnormal (some severely abnormal) knee function.

Athletes engaged in seasonal sports were more likely to get back into the game. The break between seasons gave them more time to rehab and recover compared with athletes who played year-round with no breaks.

The results of this study showed the expectation of return-to-sports within 12 months of ACL surgery may not be realistic. For a competitive athlete who decides to have this procedure thinking he or she will get back to sports sooner, this information is very important.

The authors note that using the preinjury level of participation as the key measure may be somewhat restrictive but it is a more accurate reflection of real life for athletes. They go into surgery thinking and hoping that they will be able to return to their sport fully but end up with a reduced level of playing ability. Some return to play but in a different sport — perhaps one that doesn’t involve pivoting, sudden twists and turns, or jump-land maneuvers.

One other difference from this study to others was the timing of return-to-sport. The earliest patients in this study were allowed back on the field was nine months after surgery. In other studies, athletes return as early as six months. It may seem like they do better getting back earlier but the studies don’t always use the preinjury level of participation as their measuring stick.

More study is needed to clear up some of these differences before we will know for sure. For now, it looks like many athletes may need more than the traditional six to 12-month break from sports after ACL reconstruction.

A longer period of rehab may be needed to truly get back to full sports play with no restrictions. Women may need more time than men despite their intentions to return to full function in 12 months. There may be other reasons athletes don’t return to their sport such as fear of reinjury. Psychologic factors of this type were not investigated in this study but may need a closer look in the future.

In the orthopedic world, Dr. Frank Noyes is an important name. He has been a front runner in developing new surgical techniques for a variety of orthopedic injuries. In this article, long-term results from an ongoing (and previously reported on) study are published.

The topic? Chronic knee instability treated with a femoral-fibular posterolateral reconstruction. This is the most commonly used surgical technique to stabilize a knee with multiple ligaments that are damaged. Without this important soft tissue support, posterolateral (back and side) instability of the knee joint occurs.

To be more precise, the soft tissues being replaced are the fibular collateral ligament, the popliteus muscle tendon-ligament (PMTL), the popliteofibular ligament, and the posterolateral (joint) capsule.

Without these structures, the knee slides around and can partially dislocate (called subluxation) or fully dislocate. That’s what is meant by knee instability. Together, these soft tissues work to keep the knee joint from hyperextending (extending beyond a neutral position), externally rotating too far, or opening (gapping) too much along the side.

And that’s why it’s important to do more than just repair damage to this area. In this procedure, a piece of the Achilles tendon from the back of the heel is used to replace torn ligaments along the back (posterior) and side (lateral) aspect of the knee. The surgeon actually has to rebuild (reconstruct) this group of four ligaments and capsule that make up the back/side corner of the knee joint.

Dr. Noyes performed this femoral-fibular reconstructive technique for multiple ligamentous damage to the knee. Twenty-one (21) patients (males and females) were treated with this procedure. Early results were reported in 1995. At the time of the surgery, patients were between the ages of 15 and 43. Now more than 10 years later, long-term results are compared to the early outcomes.

For those who are unfamiliar with the first study, the femoral-fibular procedure is briefly reviewed. Photographs taken during surgery help the reader understand exactly what was done during the operation. Drawings show the reader more clearly what is seen in the photos.

Basically, tunnels were drilled into the femur (thigh bone just above the knee) and into the fibula (small bone along the outside of the lower leg bone and located just below the knee joint). The Achilles tendon graft (taken from a tissue bank, not from the patient) was threaded through the tunnels with just the right amount of tension to mimic the natural ligamentous function.

After surgery, each patient went to rehab under the supervision of a physical therapist. Patients were instructed how to protect the graft from overload and stretching until healing had taken place. A special removable half-cast was used to keep the leg from extending past neutral while still allowing partial knee flexion.

The therapist guided the patients through a series of daily exercises to restore motion, strength, and function. After a month in the bivalved cast, patients were placed in a special brace that could be locked to prevent excess motion. The brace could be unlocked when the surgeon felt the knee was ready for weight.

Phase two of the rehab program involved gradually increasing weight, stress, and load on the joint (and thus on the graft). Some activities were re-introduced but not all activities were allowed. For example, swimming and bicycling were okay but high-impact or vigorous activities were not advised.

Before sharing the long-term results, it is helpful to review what happened in the first study. Results were measured using X-rays, subjective (patient reported) symptoms, motion, strength, and function. Two specific tests (the International Knee Documentation Committee (IKDC) and Cincinnati Knee Rating System) were used before and after surgery to assess joint stability.

Three-fourths of the patients had a normal or near normal result. Five patients had a failed outcome early on (during the first four months after the surgery). Those five patients had already undergone at least one (and often more than one) previous failed knee surgery.

How are all the patients doing now? Well, the good news is that 71 per cent report being able to participate in low-impact activities without pain or problems. Arthritis seems to be the most difficult long-term post-operative problem. About 28 per cent have arthritic symptoms (pain, stiffness, loss of motion) either with daily activities or with sports participation.

What conclusions did Dr. Noyes come to from this long-term study on femoral-fibular reconstruction for knee instability following multiple ligament injury? First, the success rate was good enough to consider this procedure a good treatment option. This technique does restore joint stability. It allows lateral joint gapping needed for normal movement. But it prevents abnormal lateral joint opening when stress is applied to that side of the joint.

Second, from other studies in this area, it’s clear that just replacing the popliteus muscle tendon-ligament (PMTL) without taking care of the other areas of damage leads to failure in a majority of cases.

Third, the femoral-fibular reconstruction is a fairly simple procedure. The way the graft is put in and looped around actually makes a double graft. The extra strength of this configuration tied into the fibular collateral ligament (FCL) works well. The placement of the femoral-fibular graft forms a solid foundation for the complete reconstructive procedure.

As a result, all three posterolateral structures are restored allowing for normal (or near normal) motion, function, and stability. This reconstructive procedure mimics the natural knee and that’s important for both daily activities and recreational sports.

Severe damage to the anterior cruciate ligament (ACL) of the knee often requires reconstructive surgery. The surgeon uses graft tissue taken from a donor bank (called an allograft) or harvested from the patient (an autograft). But the reported failure rate for this surgery is as high as 20 per cent. That’s one out of every five patients — an unacceptable level for any surgeon.

Taking a closer look at the studies published on this topic, there seems to be about a 12 per cent failure rate for allograft tissue. It’s possible that some specific factor about the allograft is responsible for these failures.

But as the authors of this study point out, less than one-fourth of the studies on ACL reconstructive surgery even report information about the history of the allografts used in their patients. And it could turn out to be an important variable in surgical success.

If you are thinking about having ACL reconstructive surgery with an allograft, you may wonder what should I know about donated tissue? It may be something you want to discuss with your surgeon. Ask about the risks, benefits, and expected long-term outcomes for the graft tissue used. As the authors of this report point out, surgeons may well want to pay a bit more attention to matching allograft tissue to each individual patient.

For example, donor tissue can come from patients of all ages. In the case of tendons or ligaments, there are age limits. The donor can not be more than 60 years old. Studies have not been done to show if matching the patient age to the age of the allograft is important.

But it makes sense that the stiffness and load donated tissue can withstand should match the level of activity of the recipient (patient receiving the graft tissue). And since the graft can come from one of several sources (e.g., patellar tendon, hamstring tendon, Achilles tendon, tibialis posterior, peroneus longus, fascia lata), it’s possible that age, tensile strength of the tissue, and biomechanical load each tissue can withstand before failure should all be investigated and compared.

Then there is the matter of how the graft tissue is prepared, processed, and stored for use. How was the graft tissue sterilized? It could make a difference. Did the graft come from an accredited tissue bank? There is an organization called the American Association of Tissue Banks (AATB) that sets standards for tissue processing and donor eligibility. But there’s no law that requires tissue banks to follow their guidelines.

Surgeons are advised by the American Academy of Orthopaedic Surgeons (AAOS) to use donor tissue only from tissue banks that are inspected and approved by the American Association of Tissue Banks (AATB) or the Food and Drug Association (FDA). AATB authorized donor banks test carefully to make sure the donor tissue is free of diseases, viruses, and infections such as HIV or hepatitis. The tissues are inspected, cleaned, and sterilized before being stored for later use.

It’s important to know when was the last inspection. A one-time inspection 10 years ago is not sufficient. The donor bank should be routinely inspected and pass that inspection. The bank should be providing tissue that has been processed according to the most up-to-date guidelines published by the AATB. These same guidelines are used by the FDA.

Even with donor tissue from accredited sources, there still remain many unknowns. For example, what’s the effect of all the processing, sterilization, and storage on the strength of the tissue? There is some concern that the process of irradiating the tissue at high enough doses to kill viruses can damage the collagen fibers and weakening them.

What is the oldest age of tissue that can be used in patients? Should the donor graft be matched by age or should the surgeon try to use tissue from a donor who was younger at death than the patient now receiving the tissue? If older donor tissue is used, are there age limits? What are those limits?

After reviewing published studies on this topic, the authors make several recommendations. First, surgeons are advised to learn more about how donor tissue is processed and preserved. Second, with this information, they can advise their patients about the advantages and disadvantages of allograft versus autograft tissue for ACL reconstruction. Third, surgeons may want to pay closer attention themselves to specific patient factors for both the donor and the recipient (their patient). And finally, more studies are needed in this area to improve success rates and patient outcomes.

Sports physicians, physical therapists, and athletic trainers often hear these symptoms from athletes: I have pain along the outside of my knee, swelling, and sometimes the knee locks up on me or gives way from underneath me. What is causing this?

The examiner takes a patient history with standard questions about possible injuries or trauma to the knee. He or she will ask the patient questions what makes it better, what makes it worse, and are there any other symptoms? Conducting a physical examination and performing specific tests help in sorting out what could be causing the problem.

X-rays may be ordered and all possibilities are considered. The most common problem causing this type of clinical presentation is a lateral meniscus tear. The meniscus is a thick U-shaped piece of cartilage inside the knee joint. Anything inside the joint is referred to as intra-articular.

But there can be other causes coming from outside the joint mimicking a meniscal tear. These would be considered extra-articular and include: 1) iliotibial band syndrome (ITBS), 2) proximal tibiofibular joint instability, 3) snapping tendons (either the biceps femoris or the popliteus tendons), and 4) peroneal nerve compression or inflammation.

This article was written to help the examiner recognize the subtle differences between intra-articular meniscal tears and extra-articular causes of lateral knee pain. The typical history, symptoms, and test findings are presented for each one.

Drawings, X-rays, and photographs are provided to help show each of these conditions and how they differ from a lateral meniscal tear. A brief review of the most common treatment for each condition is also offered. Since the treatment varies with each type of problem, an accurate diagnosis is needed to get these athletes back on their feet and in the game as quickly as possible.

Let’s take a quick look at each one. First and probably the most common condition to mimic a lateral meniscal tear is the iliotibial band syndrome (ITBS). This connective tissue structure runs along the entire outside of the thigh from hip to knee with several points where it inserts or connects to the knee.

Runners and cyclists have the most trouble with this problem because of the repeated knee flexion (bending) and extension (straightening). A special test called the Ober test is used to look for tightness of the iliotibial (IT) band.

X-rays don’t show positive findings for IT band problems. But they are used to look for tumors, arthritis, and fractures. MRIs are better at showing changes (e.g., thickening, fluid collection) in the connective tissue.

A second mimicker of a lateral meniscal tear is the presence of tibiofibular joint instability. The tibiofibular joint is along the outside of the knee where the tibia (larger of the two lower leg bones) connects to the fibula (smaller of the two lower leg bones).

Instability usually tells us the joint is loose or shifts either into subluxation (partial dislocation) or into a fully dislocated position. This can be caused by small but significant anatomic variations.

Even slight changes that alter the natural angle of this joint can allow the fibula to slip out of the groove that holds it in place. Or a traumatic injury damaging ligaments and connecting soft tissue can damage the joint resulting in the same type of instability.

Instability may keep the athlete from putting weight on that leg. The examiner compares the unaffected knee to the painful one and looks for changes in how the joint moves. Any unnatural shifts in the fibula as it moves against the tibia (called joint translation) will be evaluated with more specific tests (e.g., apprehension test, Radulescu test).

The third extra-articular source of lateral knee pain comes from snapping tendons. Tendons that insert into the fibula near the knee may slip back and forth over the bone causing a painful snapping sensation.

The symptom is most noticeable during knee motion. A larger than normal fibular head (round top of the fibula) can contribute to the problem. Sometimes releasing the tendon surgically and/or removing some of the bone and reshaping the fibular head are necessary to end the problem.

And finally, the common peroneal nerve located along the outside of the knee and lower leg may be irritated either from compression (pinching) or neuritis (nerve inflammation). Like all the other problems discussed nerve compression or inflammation can cause lateral knee pain. With nerve involvement, there are usually sensory (numbness, tingling) and/or motor changes (muscle weakness) to help direct the examiner in finding the problem.

Helpful clues to nerve involvement include history of trauma to the outside edge of the knee (where the nerve is located), pressure on that spot from crossing the leg, sudden weight loss (the protective fat pad gets too thin), or ankle/foot injury that stretches the nerve.

Special tests to look for nerve compression or neuritis include Tinel sign (tapping over the nerve causes nerve pain), electromyogram (EMG) studies, and nerve conduction studies. X-rays are used to look for bone spurs, fractures, or tumors putting pressure on the nerve.

In summary, more and more athletes are showing up at doctors’ and physical therapists’ clinics with lateral knee pain. It is necessary to examine carefully to identify the involved structures in order to direct treatment to the specific problem.

Intra-articular (inside the joint) problems must be differentiated from extra-articular (outside the joint) causes of symptoms. The authors of this article provide a step-by-step approach to completing such an exam with photos and descriptions of recommended test procedures for each of four separate conditions that can separate out intra-articular meniscal tears from other extra-articular injuries that can mimic meniscal tears.

There are many different ways to approach the problem of an anterior cruciate ligament (ACL) injury of the knee. A partial tear may respond well to conservative (nonoperative) care. But if rehab doesn’t yield the desired results (or in the case of a competitive athlete), the ligament may need surgical repair. The surgeon stitches the ends of the ligament back together.

A fully ruptured ACL often requires surgical reconstruction. It doesn’t work to try and pull the ends of the ruptured ligament back together — instead, a piece of tendon is taken from another area of the knee and used as a graft to replace the damaged ligament. The donor graft comes from one of two places: either the patellar tendon (just below the knee cap) or the hamstrings (behind the knee).

Research is ongoing trying to figure out which method works best. There are a lot of variables to work through in making the comparison. For example, patients of all ages, sizes, and shapes injure the ACL and need this treatment. Athletes have very different needs than older, less active adults.

The reconstructive surgery can be done with an open incision but more recently, the use of an endoscope has become more the standard of care. The endoscope is a thin, round tube that can be inserted into the joint through which the surgeon can see inside the joint as well as pass instruments and sutures down through the tube for use inside the joint.

One other confounding factor in studying ACL reconstructive surgery is the fact that two-thirds of all patients with a rupture ACL also sustained damage at the same time to other soft tissues in the knee. Only about one-third of the patients with a deficient ACL have an isolated ACL injury. By isolated, we mean the ACL injury is the only area of damage.

In this study, orthopedic surgeons from Australia have been following patients with an isolated ACL injury reconstructed who had a patellar tendon graft. They have reported on their short-term and mid-term results in previous studies. This time, it’s a report after 15 years! That time frame certainly qualifies as a long-term study.

Results have been measured using a variety of tools. Knee range-of-motion can be easily measured with a special tool called a goniometer. Stability of the joint was tested using several clinical tests well-known to orthopedic surgeons, physical therapists, and athletic trainers (e.g., pivot-shift test, Lachman test). Knee function was assessed using the single-legged hop test, the Lysholm Knee Score, and the International Knee Documentation Committee evaluation (IKDC).

They found that a full 30 per cent of the group had another ACL injury after the first one. Most of those injuries were to the ACL in the other knee. A smaller number ruptured the graft. Graft ruptures were most common in active patients who were under the age of 18 at the time of the first (initial) ACL injury. A closer look at the data also showed that the angle of the graft made a difference. Lower graft angles (measured as less than 17 degrees) were much more likely to rupture.

Stability, motion, and function were nearly normal in 90 to 100 per cent of the group. The biggest functional problem (affecting daily activities) was pain when kneeling. A second equally important finding was the high incidence of osteoarthritic changes. At the end of the first five years, one-third of the group had signs of joint degeneration (seen on X-rays). By the end of 15 years, that number had increased to 51 per cent.

Let’s go back and talk a little more about those patients who injured their other ACL. In today’s modern lingo, “What’s up with that?” The authors suspect there may be several reasons why someone with a reconstructed ACL would end up rupturing the other knee.

The first is simply anatomy, biomechanics, and genetics — in other words, the way you are put together. The second is the fact that a reconstructed ACL is actually more stable and stronger than the natural ligament that might stretch out more over time. And the third relates to patients being more protective of the reconstructed knee. Further study may uncover the exact reason(s) for this phenomenon.

In summary, long-term results of isolated anterior cruciate ligament injuries treated with reconstructive surgery using a patellar tendon graft are good. A few problems can crop up such as pain with kneeling, arthritis, and further knee injuries. Efforts to find ways to reduce knee pain after patellar tendon grafting are underway. Patients agree a little knee pain when kneeling is a small price to pay for the excellent long-lasting results they got otherwise.

Sometimes surgery to reconstruct a ruptured anterior cruciate ligament (ACL) in the knee doesn’t give the expected results. Either the patient continues to have a painful, unstable knee that gives out from underneath them or the knee is stiff and doesn’t move well. Joint infection and arthritis are two other problems that can develop.

Why does this happen? In this article, surgeons from the University of Utah explore all sides of the dilemma of the failed ACL reconstruction from patient factors to surgeon error. They offer their own preferred techniques including graft type, bone preparation, graft fixation, and technical considerations for revision surgery.

But before we look at those more closely, it might be helpful to have a quick review of the anatomy of the anterior cruciate ligament (ACL). The ACL is located in the center of the knee joint where it runs from the backside of the femur (thighbone) to connect to the front of the tibia (shinbone). The ACL runs through a special notch in the femur called the intercondylar notch and attaches to a special area of the tibia called the tibial spine.

The ACL is the main controller of how far forward the tibia moves forward under the femur. This is called anterior translation of the tibia. If the tibia moves too far, the ACL can rupture. The ACL is also the first ligament that becomes tight when the knee is straightened. If the knee is forced past this point, or hyperextended, the ACL can be torn.

Once the ligament has been damaged enough to rupture completely, surgery is needed. The surgeon uses tendon material from either the patellar tendon below the knee or the hamstring tendon behind the knee to act as a graft and replace the ruptured ACL. But reconstruction surgery doesn’t always hold up. Reconstruction failure can occur as a result of patient-related factors or surgeon error.

What happens on the patient side? Going back to demanding sports activities too soon is one potential error on the part of the patient. Overly aggressive rehabilitation can set the patient back. Too often the patient pushes past the guidance offered by the physical therapist. “More is better” is not the best motto during ACL reconstruction rehab. On the other side of the coin, too little rehab (poor patient compliance) can also contribute to a failed ACL reconstruction.

Surgeons play a role in the success or failure of ACL reconstruction. Poor graft placement, surgical contamination leading to infection, or other poor operative techniques can spell disaster. Putting the graft in the proper anatomical place but with too much or too little tension is another potential surgeon-related error.

What can be done when a torn ACL has been reconstructed and ruptures again? A second surgery called a revision procedure is often recommended. How this procedure is done depends on several factors. Length of time between re-rupture and revision surgery is one factor. Type and severity of damage done in the graft is another consideration. And technique used to perform the first reconstruction surgery is important (e.g., placement of tunnels in bone through which the graft is placed, angle of the graft as it is stitched in place).

Using diagrams (drawings) and photos taken during arthroscopic revision surgery, the authors show how to remove or work around sutures from the first (failed) ACL reconstruction. When a new tunnel must be drilled through the bone because of a malpositioned first tunnel, directions, placement, and photos are provided to guide the surgeon.

A review of hardware used to hold the new graft in place is offered. One method for graft fixation used by the surgeons is a stacked screw technique. The screws are helpful to shore up tunnels that have to be expanded while providing good holding power for the graft. Sometimes the old tunnel is filled in with bone and graft materials.

The authors discuss also how they determine the best angle for the tunnel and graft alignment. One method they use is with a guide pin. Details for prevention of injury to the nerve and joint cartilage while still getting inside the joint and putting the graft in the right position are outlined.

A variety of surgical options are presented and discussed for removal of the hardware left from the first surgery. Sometimes, it is possible to keep the old tunnels and hardware. The surgeon can either incorporate them into the new (revision) procedure or avoid and work around them.

Patients whose revision surgery ruptures (requiring a revision of the revision) are few in number. That’s good for the patients. But the lack of data makes it difficult to guide surgeons in choosing the surgical technique that will yield the best results.

From the few studies already done, it’s clear the results of a revision-revision are not as good as a successful first revision. Only a small number of athletes in this situation are able to return to sports at the level they were playing before the initial injury.

Anyone thinking about having anterior cruciate ligament reconstruction surgery must be advised that problems and complications can occur. The graft may fail completely for patient-related reasons or due to surgeon error. Most problems can be fixed but a second surgery may be necessary. Surgeons looking for advice from their colleagues on the treatment of a failed ACL graft will find the detailed information on technique in this article helpful.

People who suffer one patellar (kneecap) dislocation after another search for ways to prevent this from happening. The obvious first question is: what is causing this to happen? Most often the patella pulls away from the knee in a lateral direction. Lateral means sideways in a direction away from the other knee.

To better understand how knee problems occur, it is important to understand some of the anatomy of the knee joint and how the parts of the knee work together to maintain normal function. The knee is the meeting place of two important bones in the leg, the femur (the thighbone) and the tibia (the shinbone). The patella is also made of bone and sits in front of the knee.

The patella is held in place by its shape and the supporting soft tissue structures such as muscle, tendon, cartilage and ligaments. As the knee moves, the patella glides up and down in front of the knee joint. There is a groove on the front of the femur (the trochlear groove) of the femur. The back of the patella has a corresponding V-shape that fits inside the groove and helps hold it in place.

Any changes in the shape of the bone, alignment, ligamentous laxity (looseness), muscle weakness, or other soft tissue problems can contribute to patellar instability. In this article, trochlear dysplasia is the focus as a possible cause of recurrent (repeated or chronic) patellar dislocation. Trochlear dysplasia refers to a groove that is shallow — too shallow to hold the patella in place as it glides up and down.

A shallow groove by itself may not be enough to really result in chronic patellar instability. Experts think there are multiple factors contributing to the problem. Each factor must be addressed in treatment in order to keep the patella centered in the trochlear groove. Preventing further patellar dislocations requires evaluation of the bony, soft tissue, and alignment issues.

What’s the first step in the process? The examiner will need to figure out if the knee is giving way because it hurts or if there is pain because the patella is unstable leading to dislocation. Interviewing the patient helps create a picture of what’s happening and when it’s occurring. The duration and severity of the problem will be revealed through this process.

Next, the examiner performs an evaluation looking at motion, strength, alignment, tissue integrity, ligamentous laxity, position of the patella, and so on. One of the most accurate tests for patellar instability is called the apprehension test.

In this test, the patient’s patella is pushed to the side as the knee is bent. A positive response occurs if the patient’s quadriceps muscle starts to contract during this movement or if the patient feels like the kneecap is going to pop off center and dislocate again. Patellar movement is also evaluated with the knee in full extension.

X-rays are next. X-rays help show any unusual patellar shapes that might be part of the problem. There are special views that can be taken to show the position of the patella in the trochlear groove, the depth of the groove, and how well the two bones match up. In some cases of patellar instability, the patella is riding up above the groove. This condition is called patella alta. This is one of the many alignment factors that can put the knee at risk for dislocation.

The radiologist also looks for the presence of the crossing sign on X-rays as an indicator of trochlear dysplasia. This sign is visible when looking at the knee from the side. It is an indicator of the depth of the trochlear groove.

Once all the information has been collected, the surgeon can begin to determine the best plan of action. Conservative care with a rehab program under the guidance of a physical therapist may be helpful in addressing some of the soft tissue and alignment factors. Surgery is more effective when trying to change the bony factors including trochlear dysplasia.

There are several different surgical approaches that can be taken. For example, the surgeon can perform a trochleoplasty. In this procedure, a piece of bone is removed from the trochlear groove and the area is deepened and reshaped. A different approach would be to use bone graft material to build up the lateral (outside) wall of the groove. Or the surgeon might change the rotational angle of the femur so the two bones (femur and patella) line up as they are supposed to.

The idea that trochlear dysplasia plays a significant role in patellar instability is fairly new. Which surgical technique to use has not been studied fully. The few studies that have been done report good results with trochleoplasty (no more dislocations) but knee pain and swelling continue. Arthritic changes in the knee joint are typical after any of these procedures.

Additional surgery to change the biomechanics of the knee may be needed. For example, the ligaments on either side of the knee (the medial and lateral patellofemoral ligaments) must each exert the right amount of tension at various points in the knee range-of-motion. If they do not, the patella can be pulled too far in one direction or the other and dislocate. Restoring normal constraints offered by these ligaments can also provide stability and offset a deficient trochlea.

The authors conclude by saying that repeated dislocations of the patella (kneecap) may be difficult to treat without surgery. Many factors are at play here but new insights suggesting a closer look at trochlear dysplasia as a key player have been reported. Anatomy, biomechanics, and causes of this condition are explored. Treatment as it has been developed so far is reviewed. Expect to see more on this topic in the coming years.

Knee replacements are great to have around but they don’t last forever. Younger, active adults who experience degenerative arthritis of the knee may be too young for a knee replacement. It’s likely they will outlive the implant. Getting a second knee replacement is not usually an option. So what can be done instead?

Anyone with chronic knee pain who has been evaluated by an orthopedic surgeon and diagnosed with early stages of degenerative arthritis can begin with conservative (nonoperative) care. Activities can be modified to reduce stress and load on the joint. Weight loss is advised for anyone who is overweight. Physical therapy to improve posture, alignment, motion, and strength is often helpful.

But when the joint is worn down to the end-stages of arthritis, then surgery is often required. In this study, one particular type of knee arthritis is investigated. Medial compartment osteoarthritis (MCOA) affects just one side of the joint — medial refers to the side closest to the other knee.

Misalignment of the hip, knee, and/or ankle leading to an uneven weight distribution contributes to the development of medial compartment osteoarthritis (MCOA). Surgery to correct the problem consists of: high tibial osteotomy (HTO), unicompartmental knee arthroplasty (UKA), or total knee replacement (TKR).

One surgeon performed 455 high tibial osteotomies in patients with medial compartment osteoarthritis and then surveyed long-term results up to 19 years later. The results are the subject of this study. High-tibial osteotomy refers to a surgical procedure where the surgeon removes a wedge-shaped piece of bone from one side of the tibia (lower leg bone). The word “high” tells us the wedge is taken out of the tibia at the top of the bone near the knee (rather than down low by the ankle).

There are different ways to do a wedge osteotomy — the bone can be removed from the medial side of the tibia or from the lateral side (opposite the medial side or the side away from the other knee). The patients in this study all had a high-tibial lateral closing osteotomy. You know that a high osteotomy refers to where the bone is removed from (upper part of the tibia).

You know that a lateral osteotomy is taken from the outside edge of the tibia. But what does a “closing” osteotomy mean? That’s where the piece of bone is removed and the two remaining edges of bone are shifted together (the hole made by removing the bone is closed). The goal of a lateral open osteotomy for medial compartment osteoarthritis (MCOA) is to shift the weight off the medial side of the joint. By shifting the weight-bearing load, the medial joint surface gets a break and the tension on the knee ligaments can be corrected.

The surgeon who did the operations wanted to know several things: 1) did the procedure hold up over time? 2) what factors helped predict success or failure? and 3) were the patients satisfied enough that they would do it all over again if they had the chance?

In order to find out how everyone answered those questions, the patients were all contacted by phone and interviewed. Questions were asked about height and weight to calculate body mass index (BMI). The British Orthopaedic Association Patient Satisfaction Scale was given to each patient who participated. Function was assessed using the Oxford Knee Score and failure was determined by the need for further knee surgery.

What did they find out? Were there any surprises? First, a little bit about the patients. There were far more men in the study than women (3:1 ratio). Patients ranged in age from 24 to 70 years old. There were an equal number of right and left knees involved.

Complications included blood clots to the lungs, deep vein clots in the legs, hematoma (pocket of blood) pressing on a nerve, and bone nonunion. One-third of the group did have a second surgery — either to revise the osteotomy or to replace the joint. But 85 per cent said they were satisfied with the results and would have the same procedure again if they had it to do all over again.

Further analysis of all the data collected showed there were some predictive factors for success — in other words, patients with these particular characteristics were more likely to have better long-term survival of the joint. The three most significant predictive factors for success were lower body weight (BMI less than 25), younger age (less than 50 years old), and a weak or deficient anterior cruciate ligament (ACL).

A BMI greater than 25 signals overweight. Obesity is defined as a BMI greater than 30. For patients with a damaged, injured, or ruptured anterior cruciate ligament (ACL), the high-tibial osteotomy provided the stability needed to prevent further joint damage.

In summary, high-tibial osteotomy is an effective way to treat medial compartment osteoarthritis (MCOA) of the knee. Studies have shown that the joint cartilage that’s worn down can regrow when pressure is eased off that area. Results do deteriorate over time but many patients buy as much as 15-years of time before needing a total knee replacement.

When you are under age 50, that’s a pretty significant benefit of the procedure. Reduced pain, improved function, and better quality of life make this a viable treatment option for younger, more active adults who aren’t quite ready for a knee replacement.

Adults who have a total knee replacement often ask their surgeons, “How soon before I can drive?” Even more than the patient who has a total knee replacement, concerned family members want to know, “Is it safe to drive?” The usual guideline for return-to-driving is six to eight weeks after surgery. Driving restrictions primarily apply to patients who have had a right knee replacement (assuming they drive an automatic vehicle).

But the question has come up about getting back behind the wheel sooner with the new and improved procedures. With less soft tissue disruption, muscle strength and motor control should come back even faster than with traditional procedures.

To find out if this theory is correct, occupational therapists measured brake time response before and after right total knee replacements in 29 patients. Patients were allowed to return to driving when the postop braking time was equal to (or faster than) the preop braking level.

Patients enrolled in the study were between the ages of 47 and 81, still driving, and had a diagnosis of osteoarthritis. Surgery was done by one surgeon for all 29 patients using the same surgical technique, anesthesia, and implant. Likewise, everyone was given the same preop procedures and postop care (including intense rehab).

All but three of the patients were discharged from the hospital directly to home by day three following the procedure. The remaining three patients went to an inpatient rehab center for a few extra days but were home by day eight. Brake time was tested at regular intervals after the replacement surgery (at four weeks, six weeks, and eight weeks postop).

Occupational therapists specialize in assessing function and ability to complete daily tasks and activities. As such, they are the health care professionals who test for ability to drive. In this study, a testing device (Vericom stationary reaction timer) was used. The set up included a computer monitor with video of driving down the road, steering wheel attached to a table, and pedals on the floor.

Driving was simulated with acceleration (pushing down on the gas pedal) and stopping by pressing on the brake pedal. Red and green lights signaled the driver when to accelerate and when to brake. The computer program measured and recorded the reaction time. Reaction time included time from foot at rest to gas pedal, time to lift foot off the gas pedal (called “gas off”), transition from gas to brake, and braking.

The patient’s age and gender were also factored in to see if either of these variables made a difference in reaction time. The results showed that neither one made any difference in ability to react in a braking situation. And everyone in the study was back to their preoperative braking reaction time by the end of four weeks.

The improved surgical techniques, better pain control, and advanced rehab protocols have now put patients back in the driver’s seat so-to-speak. With less pain, faster return of knee motion and mobility, patients experience better function sooner. Many patients feel ready to quickly regain the social independence driving provides.

The authors of this study were not quite ready to say all total knee patients can be released and return-to-driving after four weeks. This is just the first study they designed to address the question. There are other factors to be considered that weren’t tested for such as vision, overall reaction time, effect of narcotics or other medications, and other health concerns.

They did check a smaller group of eight patients from the original 29 to see how they did after just two or three weeks compared to their brake reaction times at four weeks. They found that six of the eight patients in the subgroup passed at the two-week mark. Another patient passed at week three, and the final one passed at week four. This information suggests that many patients may be ready even before the four week cut-off.

Future studies will be needed to continue investigating this topic and forming guidelines for return-to-driving after right knee replacement. Separate testing should be done for automatic versus standard transmission vehicles. Any one who passes the brake test but who might need additional testing can be evaluated more completely with an on-the-road test.

By far more patients have a total knee replacement (TKR) over a unicompartmental knee arthroplasty (UKA). The risk of having additional surgery after a unicompartmental implant may be the driving factor behind this decision. This study was done to compare results after both procedures.

The difference between a total knee replacement and unicompartmental knee arthroplasty is more than just the implant itself but let’s review that first. As the name suggests, with a total knee replacement (TKR), the surgeon removes the entire damaged knee joint and replaces both the upper and lower sides of the joint.

The unicompartmental arthroplasty (UKA) involves just replacement of the inner or outer half of the joint. Most patients having a UKA have problems with knee alignment and have worn out just the medial joint surface. Medial refers to the side closest to the other knee.

The idea behind a UKA is that there’s no need to replace the entire joint when only one-half is compromised. Other advantages of the UKA include a shorter hospital stay, fewer infections, and faster recovery. Studies show patients having a UKA are at lower risk for blood clots. They also have less pain after surgery compared with a total knee replacement (TKR).

The major stumbling block with a unicompartmental knee arthroplasty (UKA) is the revision rate (second surgery). It is twice as high for UKA compared with a total knee replacement (TKR). There are several reasons for the higher failure rate of the UKA. The unicompartmental implant is more likely to come loose. Bone fractures around the implant are also more common in this group.

The authors of this study from Norway compared outcomes for the unicompartmental versus the total knee replacement. Norway has an established registry for arthroplasties (implants) making this type of comparison possible with a large number of patients.

All patients having any artificial joint implants in Norway are registered. Information about their diagnosis, age, joint involved, and surgery performed is included in the database. Baseline pain and function are not part of the registry information, so patients selected to be in the study were sent a survey of questions by mail.

Patient selection was based on current age (less than 85 years) and when the surgery was done (at least two years ago). Differences in results were compared by implant type and brand, patient age, sex (male versus female), and time since the operation.

As shown in previous studies, the unicompartmental knee arthroplasty did have more favorable results with less pain and better function at all time points. But the differences weren’t all statistically significant. And when asked about quality of life, patient ratings were equal between the two groups.

The authors took a closer look at various implant brands (i.e., made by different manfacturers). Again, there weren’t significant differences among the three prostheses included.

One difference that did stand out was based on sex. Men with unicompartmental arthroplasties (UKAs) had less pain and better knee motion and function compared with women who had the same implants. The men also had better scores for function based on daily activities, sports, and recreational activities.

In summary, there are only small differences in results to favor unicompartmental arthroplasty (UKA) over total knee replacement (TKR). Better motion leads to better function and performance. The most likely reason for the increase in quantity and quality of motion with UKA is the preservation of knee ligaments and overall knee anatomy made possible by the UKA.

The lack of a big difference between UKA and TKR came down to two main variables. One was the fact that there were more UKA implants that came loose. And secondly, more arthritis developed in the knees of patients with a UKA requiring further surgery (usually conversion from a UKA to a TKR).

The authors concluded by saying their Norwegian Arthroplasty Register with its large number of patients makes this type of research possible. They had over 1300 participants and plenty of patients with each implant design to make comparisons possible. Equal results among the different brands suggest it may not make a difference which one the patient gets. More study is needed to verify this idea.

With equal results but higher revision rates with the unicompartmental arthroplasty (UKA), it may be better to go with a total knee replacement (TKR). Only patients needing more knee flexion might find the UKA a better choice.

For the patient who has a total knee replacement, knee stiffness can be very disappointing and limiting. Imagine not being able to go up stairs foot after foot (that requires 83 degrees of knee flexion). Or not being able to sit down and tie your own shoes (you need 106 degrees of knee flexion for that).

This type of stiffness is fairly common after a knee replacement. What be done about it? Right now, there are two main options. You can try the conservative route with exercise and manual therapy under the supervision of a physical therapist. If that doesn’t work, then surgery is advised.

The surgeon must choose among three choices: 1) manipulation under anesthesia (MUA), 2) arthroscopic exam and debridement, and 3) open incision with revision. During manipulation under anesthesia, the patient is asleep while the surgeon moves the joint through its full range-of-motion. This forced movement breaks through areas of fibrosis and scar tissue. Debridement refers to gently scraping away any adhesions or fibrotic tissue that is keeping the joint “stuck” or unable to move beyond a certain point in the range of motion.

Arthroscopy allows the surgeon to see inside the joint and find out what’s holding it back from moving normally. Using a long, thin needle with a tiny TV camera on the end (the arthroscope, the surgeon can then correct the problem. If necessary, an improperly positioned implant can be removed and replaced using an open incision.

But which one of these approaches should be used? And how successful are the procedures? Surgeons from the Department of Orthopedics at the Mount Sinai Hospital in New York City conducted a systematic review in an attempt to answer these questions. They reviewed all of the articles on the three surgical techniques just described published between 1966 and 2008.

They only found a small number of high quality studies on each one. There wasn’t a large number to help guide surgeons in developing a standard of care. Each article was reviewed for information on age of patients, sex (male versus female), timing of the procedure after total knee arthroplasty, technique used, and type of anesthesia used.

Results of each treatment approach were measured using change in knee motion and total motion. Any complications that affected the patients recovery or outcomes were also analyzed. The first question addressed was how soon to do something about a stiff knee after knee replacement. The answers ranged from two weeks to three months after the initial replacement surgery.

Many surgeons send these patients to a physical therapist first before considering manipulation or a revision surgery. After exploring when to do the surgery, they turned their attention to the “How” question. How should the surgery be done? Which technique (manipulation, debridement, revision) should be done to get the best results?

This is where the poor quality of study design failed us. Too many studies did not specify if manipulation was (or was not) done at the time of the arthroscopy. The general trend was to report when manipulation was performed. Most studied did not mention when arthroscopic exam was not accompanied by a manipulation procedure.

Some surgeons reported removing scar tissue, releasing tight soft tissues, and changing the size of the implant to a smaller one. As for the “What” question: what was the effect of each surgical procedure on joint motion (and stiffness)? Here again, the studies did not always report both the changes in range of motion and the total range of motion.

For those who reported a final increase in knee flexion, the results varied from five degrees of improvement up to almost 60 degrees of increased knee flexion. Knee extension wasn’t always measured or reported. When it was, the increase was anywhere from two to 23 degrees. In a few cases, patients actually lost range of motion (extension) after arthroscopy.

The last two areas studied included timing of the surgery and complications. Only one article discussed timing so there’s no general consensus on this point. Complications varied from study to study. Although there were blood clots, hematomas (blood into the joint), fractures, instability, implant breakage, and wound infection, there wasn’t one particular complication that occurred most often.

After reviewing and analyzing all the studies, the authors could make these observations:

The patella (more commonly known as the “kneecap”) moves up and down in front of the knee joint along a built-in track called the patellofemoral groove. It is held in place by several ligaments on either side and by the patellar tendon (attached to the quadriceps muscle). The quadriceps muscle is the large, four-part muscle along the front of the thigh.

Although you can take your hands and passively move the kneecap from side to side, this is not an active movement you can make your patella do without assistance. We call that side-to-side (medial-to-lateral) movement accessory motion. The up-and-down and side-to-side accessory motions are referred to as patellar glide.

As part of the patellar tendon, there are slips of ligamentous fibers that help hold the patella in place and keep it from moving too far to one side or the other. On the inside of the kneecap is the medial patellofemoral ligament. On the outside is the lateral patellofemoral ligament.

Without the medial patellofemoral ligament, the kneecap dislocates laterally (in a direction sideways away from the other knee). Because the medial patellofemoral ligament is connected with other ligamentous structures, complete rupture will likely damage other areas as well. The medial patellofemoral ligament attaches above to the femur (thigh bone) and below to the tibia (lower leg bone).

Most ruptures occur at the femoral attachment. But the ligament can tear away from the tibial attachment or even in the middle (not at either bone attachment). This type of tear is called an intrasubstance tear.

A medial patellofemoral ligament injury can be treated conservatively without surgery. The knee may have to be immobilized in a splint for a number of weeks to allow for healing. Physical therapy, taping, and a home program of exercises prescribed by the therapist begin after the period of immobilization. The rehab program must be given the good old college try: in other words, for more than a few days or weeks. It can take months to rehab this injury.

But if nonoperative care fails and the patella dislocates again, then surgery to repair or reconstruct the ligament may be the next step. The surgical approach that works best depends on the underlying damage and specific patient factors.

The surgeon will use an arthroscope to look inside the joint and assess the damage before performing the actual repair. In this study, there was an equal number of patients with medial patellofemoral tears at the femoral, tibial, and intrasubstance locations.

Results were viewed in terms of final outcome (patellar stability or instability with another dislocation) but also included clinical data. Range of motion for the hip and knee was measured.

X-rays were taken to look at the position and angle of the patella over the femur. Knee function and disability were also measured.

Nearly three-fourths (72 per cent) of the patients had a stable patella with no episodes of redislocation. A majority of the patients (88 per cent) were able to go back to playing sports at the same level as before the injury. One-third of the group was involved in multiple sports so they were very happy to be able to continue participation as before the injury.

One important finding was the way in which sutures were placed during the repair. When the surgeon reattached the ligament where it belonged, there were no recurrent or repeat dislocations. When the ligament was sutured in a nonanatomical place, the risk of recurrent dislocation went up considerably.

A second bit of information gleaned from this study was the importance of the ligament repair tension. Too loose or too tight and the risk of failure increased because of the effect of the patellofemoral ligament on patellofemoral joint forces.

The surgeon must carefully test the ligament tension during the operation. A “too tight” repair will eventually cause patellar overload and damage to the cartilage along the backside of the patella. The patient experiences knee pain and eventual arthritic (degenerative) changes.

Surgeons reading this report will find their comments about the need for a tibial tubercle transfer for some patients. The tibial tubercle is a bump on the front of the tibia where the patellar tendon (with some of the medial patellofemoral ligament) attaches.

The placement of this bit of bone (if off to the side) can cause too much torque or pull on the ligament. It also changes how the patella tracks up and down along the patellofemoral groove. Most of the failures in this study had an abnormal tibial-tubercle trochlear groove (TT-TG) distance.

A TT-TG distance of more than 20 millimeters is suggestive of the need to perform a tibial tubercle transfer. The TT-TG distance is not something that can be measured on X-ray or with a clinical exam. It must be evaluated with CT scans. More study is needed to further explore this concept before recommending CT scans for everyone with recurrent medial patellar dislocation.

In conclusion, the 72 per cent success rate is an encouraging statistic for athletes with chronic medial patellar dislocation. Equally exciting is the fact that so many were able to return to full participation in the sports of their choosing. The authors suggest that success rates and satisfaction are higher when the damage isn’t just repaired (ligaments reattached) but when graft tissue is used to reconstruct the torn structures.

And one final parting piece of advice: these surgeons recommend using fluoroscopy. This type of imaging (real time, 3-D radiographs) used while performing the procedure makes it possible to get the anatomical repair needed for optimal results.

Injuries to the anterior cruciate ligament (ACL) of the knee are all too common in athletes. But they can also occur in older, active adults. What type of tissue graft works best? Should it be an autograft (taken from the patient) or an allograft (donor tissue from a donor bank)?

Besides the allograft vs. autograft decision, there are two popular places where the tissue can be harvested. The first is from the patellar tendon just below the kneecap. This graft is referred to as the bone-patellar tendon bone (BPTB) graft. As the name suggests, the harvested tendon comes with a tiny piece of bone.

The second is a hamstring graft. Tissue is taken from two separate sites of the hamstring muscle. Each graft is folded over to form a quadruple (four-part) graft. This is the strongest graft and referred to as quadruple hamstring graft.

Either source of tissue (patellar tendon or hamstring) can be an autograft or allograft. There are advantages and disadvantages for each one. The authors of this article (two orthopedic surgeons from the Department of Orthopaedic Surgery and Sports Medicine at the University of Kentucky) state their preferences and explain their thinking.

Here’s a quick recap of their preferences. We’ll fill you in on more details right after the list:

The number of surgeries to replace part or all of the knee joint has tripled in the last 10 years. Along with that increase has come many changes in the way reconstructive knee surgeries are done. In this specialty update, all aspects of knee surgery are researched and reviewed.

What can you expect to find in this article? First, an analysis of trends and costs associated with knee surgery. Then the authors present an update on surgical techniques and complications. These two sections are followed by a summary of outcomes (results) for each type of implant and in specific patient groups. Let’s look at each one of these and see what’s new.

Along with an increase in volume (number) of reconstructive knee surgeries has come a push to reduce costs. By studying data from hospitals, it looks like the time it takes to do a knee replacement has dropped by 20 minutes in the last 15 years. They say that “time is money” and that applies to hospitalizations. Longer operations cost more and increase the risk of complications.

There’s been a trend away from hospital-based surgeries as more surgeons specialize in a particular procedure such as reconstructive knee surgery. That has led to high-volume specialty centers where surgeons perform many knee joint replacements each week. The result has been improved outcomes, fewer complications, and lower costs.

With improved technology, surgeons have been able to offer patients improved standard of care. For example, computer navigation and tools to make more specific cuts have reduced differences that occur from surgeon to surgeon. More careful attention to the mechanical axis of the implant has also improved how long the implants last. A natural outcome of that focus has been improved function for patients.

Another change in how surgeries are done has been the move from open incision to minimally invasive surgery. Many, many studies have been done comparing the two methods. Is one better than the other? With less cutting are there fewer complications? Does the surgery take less time with minimally invasive procedures and thereby save money?

Along with smaller incisions that preserve the soft tissues has come a concept called rapid recovery rehab. Patients are up and walking and putting weight on the knee right away. Everything in the rehab protocol is speeded up. Although the improved short-term results with a faster rehab cycle have been shown, there are still too many mixed or opposite results reported when comparing minimally invasive to open incision surgeries to say for sure that one is superior to the other.

Two other areas that were reviewed included patient outcomes and complications with each of the major types of joint implants. Let’s start with types of implants. There’s the standard (cruciate ligament retaining) knee design, high-flexion, mobile-bearing, fixed-bearing, and patellar replacement versus resurfacing. Each of these was developed with specific problems or patient factors in mind.

One way surgeons have to compare results with the various choices is to use one implant type in the left knee and a different implant in the right knee. Studies of this kind have helped show that the high-flexion implant really doesn’t have any advantages over the standard design. Patients in both groups and who had one of each had the same long-term results in terms of motion and function.

When comparing the mobile-bearing implant with its movable, rotating platform to the fixed-bearing design, again, surgeons found no difference in results between the two groups. They looked at pain, motion, function, patient preference, and even survival of the implant (how long it lasted).

What about the patellar component (the kneecap)? Does knee pain improve if the back of the patella (next to the knee joint) is resurfaced? Resurfacing involves smoothing down the uneven spots and jagged edges of the cartilage behind the knee. The surgeon may put a thin plastic liner along the back of the patella as well. Is it better to leave the kneecap alone or replace it all together? This is one area where some differences were measured over time. Although it’s still not clear if persistent knee pain is caused by the patella, reoperation rates are higher for patients who don’t have the patella resurfaced.

And in the final area of analysis, the authors summarized their findings regarding patient complications and results in specific patient groups. It looks like patients who have other health issues have an overall higher rate of complications and increased risk of poor outcomes with their knee implant. Dislocations, deep infections, and implant loosening and failure were observed in the group at-risk due to poor health.

Implant failure requiring reoperation is most commonly linked with infection. Risk factors include male sex, patients with rheumatoid arthritis, and history of bone fracture anywhere around the knee. Infection is less likely when implants are put in place with cement that has antibiotic in it or when the patient is receiving intravenous (IV) antibiotics directly to the bloodstream.

Additional factors that increase the risk of infection include obesity (body mass index greater than 50), diabetes, and younger age. Diabetes was actually a major complicating factor. Patients with diabetes were more likely to suffer serious complications of surgery such as stroke, delayed wound healing, and amputation because of deep, uncontrolled infection.

In summary, there have been many changes in how total knee replacement surgeries are carried out. Type of incision made, type of implant used, and risk factors for failure have changed in the last 15 years. Advances in technology and high-volume specialty practices have contributed to improved outcomes for patients with reduced costs. The lack of convincing evidence to support one implant type over another has been an unexpected result of ongoing studies.

With the aging of America and increased incidence of obesity, surgeons expect the number of total knee replacements done in the U.S. each year to continue to escalate. Review studies like this one help surgeons and patients see where we are headed and make course corrections if necessary and as needed.

Knee injuries resulting in anterior cruciate ligament (ACL) tears are fairly common — especially in athletes and sports participants. With full tears, ACL reconstruction is usually required. Most athletes are concerned with how soon can they get back into action on the court or in the field. An equally important question is: how well does the new ACL hold up over time? Is osteoarthritis inevitable?

To find out, this group of sports physical therapists and orthopedic surgeons performed a long-term (15-year) study of patients who had an ACL injury. Some of the patients had just the ACL tear. Others had additional damage done at the same time (e.g., meniscal injury, cartilage lesions, other ligament damage).

Everyone in both groups had an ACL reconstruction surgery. The goal of surgery was to restore stability and function of the knee joint. Without the ACL to hold the two bones of the knee together (the femur or thigh bone and the tibia, the lower leg bone), the tibia can slide too far forward away from the femur.

The graft used to replace the ruptured ACL was taken from the patellar tendon (just below the knee cap). This graft procedure is called a bone-patellar tendon bone (BPTB) autograft. Autograft means the graft tissue came from the patient’s own knee.

It should be noted that the patients who had additional injuries to the same knee may or may not have had those injuries repaired at the time of the ACL surgery. For example in some cases, meniscal tears were repaired, removed, or left alone. Anyone with chondral (cartilage) lesions may have had the edges shaved down to smooth the area, but full repair was not made.

Results for these two groups were compared in terms of motion, function, strength, and activity level. Everyone was followed early on (six months after surgery, one year later, two years later) and then rechecked at 10 and 15 years after the procedure.

X-rays were used to document any signs of osteoarthritis. Narrowing of the joint space, presence of bone spurs, and deformity of the bones at the joint were evaluated to grade the severity of arthritic changes.

One thing that makes this study different from others like it is the way they looked at osteoarthritis. Most studies just report how many patients developed osteoarthritis down the road after ACL surgery. In this study, they compared how many patients had signs of arthritis on X-ray without symptoms and how many had visible changes with symptoms. Pain was the primary symptom used to say whether or not the patient had symptomatic radiographs (X-rays).

The authors also took a closer look at how additional injuries affected function. In other words, they compared patients with ACL, meniscal, and/or cartilage damage to those who had just an isolated ACL tear. How did their X-rays look 10 to 15 years later? Which group had more symptoms of arthritis?

Because they were looking at so many different findings, it might be easier to show you the results in a list:

Revision surgery (a second procedure) to reconstruct a ruptured anterior cruciate ligament (ACL) is fairly rare — thank goodness! They call this a low volumesurgery. But that makes it difficult to study the results of the first surgery and predict outcomes for the second (revision) procedure.

That’s why this group of surgeons got together and formed the MARS group. MARS stands for Multicenter ACL Revision Study Group. By combining patients from multiple centers under the care of multiple surgeons (87 total), it was possible to gather data on 460 patients.

For those of you who understand the complexities of research, you will be impressed to know what went into being one of the centers or surgeons included in this study. Membership in the American Orthopaedic Society for Sports Medicine was a requirement.

Attendance at a special surgeon training session was the next step. Everyone viewed videos of knees to unify how injuries were classified for the study. A manual of operating procedures was also required reading and study. Once everyone was on board and all the proper paperwork completed, then patient enrollment could begin.

The basic requirements for being in the study were: 1) an initial diagnosis of ACL deficiency, 2) surgery to reconstruct the ACL, 3) failure of the reconstruction requiring a second surgery, and 4) a willingness to stay in the study for two years.

Information collected on each of the 460 patients included typical demographic variables such as sex (male versus female), race, and age at the time of the revision. Type of first injury, type of graft used, reason for graft failure, and time between surgery and failure were recorded.

They also looked at the presence (size, location, and severity) of injury to other soft tissue structures in the knee at the time of the ACL injury. And a summary of tools used during rehab (e.g., bracing, limited weight-bearing, range-of-motion) was provided.

By combining data from a large number of patients, it is possible to conduct a research analysis called a multivariable analyses. With all the various factors that could affect treatment outcomes, this type of research design allows the surgeons to find variables that might predict treatment success or failure.

The results showed a group of mostly Caucasian (white) adults who injured (and reinjured) themselves playing sports that required jumping or cutting/changing directions suddenly.

Soccer and basketball were the two sports activities named most often but skiing, volleyball, gymnastics, football, and baseball or softball were also reported. A smaller number of patients were engaged in “other” activities listed as biking, cheerleading, dancing, martial arts, roller skating, tennis, hockey, jumping on a trampoline, or wrestling.

This study showed that multiple factors are probably at play here. The results of previous (much smaller) studies seemed to point to technical problems such as tunnel malposition for the graft as the most likely reason for graft failure.

And, in fact, this study confirmed that technical considerations are important. But age, type of graft (bone-patellar tendon-bone), and injury to the knee cartilage were also significant factors. The source of the graft (whether taken from the patient or from a donor bank) might be important but this study was unable to prove that one way or the other.

Women tended to reinjure their knees after the first surgery at an earlier age than men. Most ACL failures (62 per cent) occurred two or more years after the initial reconstructive surgery. About one-third presented during the first or second year post-op.

In summary, this is the first study of its kind to examine risk factors or predictors of failure after ACL reconstruction surgery. Using a large-scale research network in the United States and Canada, collective expertise from 87 surgeons was possible. With this type of high-level evidence, surgeons have the information they need to better counsel patients who reinjure a previously surgically reconstructed ACL.

Adults with osteochondritis dissecans (OCD) of the knee are advised to have surgery because their bones are fully grown. Their symptoms of pain, swelling, catching, and locking of the joint won’t go away unless the bone fragments are reattached or removed. Younger patients with OCD have a chance for healing because there is a better blood supply to the growing bone and less fibrous tissue already formed between the bone fragments.

Osteochondritis dissecans (OCD) is a disorder of the bone with a fracture in the joint surface that doesn’t heal naturally. The problem can affect the elbow, ankle, or knee. OCD of the knee mostly affects the rounded end of the lower femur (thigh bone). This area is called the femoral condyle of the knee. Like most joint surfaces, the femoral condyles are covered in articular cartilage. Articular cartilage is a smooth, rubbery covering that allows the bones of a joint to slide smoothly against one another.

The problem occurs where the cartilage of the knee attaches to the bone underneath. The area of bone just under the cartilage surface is injured, leading to damage of the blood vessels to the bone. Without blood flow, the area of damaged bone actually dies. This area of dead bone can be seen on an X-ray and is sometimes referred to as the osteochondritis lesion.

The lesions usually occur in the part of the joint that holds most of the body’s weight. This means that the problem area is under constant stress and doesn’t get time to heal. It also means that the lesions cause pain and problems when walking and putting weight on the knee. It is more common for the lesions to occur on the medial (inside) femoral condyle, because the inside of the knee bears more weight.

In the skeletally mature adult, the best treatment remains unclear. Surgeons try to preserve the bone fragment(s) by reattaching them to the bone with screws, pins, nails, darts or some combination of these fixation devices. Even with surgery, OCD can lead to future joint problems, including degenerative arthritis and osteoarthritis.

Newer bioabsorbable fixation is now available. But the results of using this type of fixation that gets absorbed by the body (and doesn’t have to be removed) are unknown. In this report, surgeons from the Mayo Clinic Orthopedic Department share the results of using bioabsorbable fixation in 18 adults with osteochondritis dissecans (OCD) of the knee. Most of the patients (14 of the 18) were men. All patients included in the study were between the ages of 14 and 39.

Arthroscopic exam of the knees confirmed unstable lesions with crater-like holes in the joint and loose fragments of cartilage and/or bone. Surgery to move the fragments back into place (a procedure called reduction) and fix them in place was done by one of six different Mayo surgeons. Everyone was followed for at least a full year. Some patients remained in the study follow-up for more than 10 years. They used three different ways to measure the results: clinical tests, improved function, and X-rays to document the status of the bone.

In two-thirds of the group, the fragment adhered to the bone in what is referred to as fragment union. One-third of the group ended up having the loose piece taken out in a separate surgery later. Bioabsorbable nails (with no threads like the screws) had a tendency to break or back out. When that happened, the patient had a new hole in the joint surface of the femur and sometimes another one on the tibial (lower leg bone) side.

The authors concluded that in all honesty they couldn’t recommend bioabsorbable fixation for OCD lesions in skeletally mature adults. There were too many problems and a low healing rate. This treatment approach clearly is not superior to others such as using metal fixation or drilling tiny holes into the joint surface to stimulate healing, a procedure called microfracture.

Efforts to improve results with bioabsorbable fixation devices will continue because metal screws can also back out, loosen, damage the joint surface, and require a second surgery to remove them. Bioabsorbable fixation has the added advantage of gradually transferring stress to the bone as the material dissolves. Additional disadvantages include failure to dissolve or disintegration at different rates within the bone. Studies are needed to see if this type of unpredictable or uneven absorption makes any difference in the final results.