FAQ Category: Knee

Most of the time, anterior cruciate ligament (ACL) repairs or reconstruction go very well. The results are as intended and expected. Patients regain full use of the knee and return to their preferred activities — even at a level equal (or better) than before the injury. But unfortunately, there is a group of patients who end up needing a second knee surgery — and even sometimes surgery on the other leg.

Your question: how can you tell if this scenario might happen to you is a good one. An investigation performed at the Vanderbilt University Medical Center in Nashville, Tennessee may shed some light on both the rate of second surgeries and the risk factors (or “predictors”) for subsequent surgeries.

They followed almost 1,000 patients over a period of six years after ACL reconstructive surgery on one leg. Any further surgeries on the involved leg or the other knee were reported and analyzed. They found a surprising number of patients required additional knee surgery on the same leg that had the first ACL reconstruction (18.9 per cent). That is almost one out of every five patients. And another 10 per cent (one out of every 10 patients) later had surgery on the other knee.

What happened that these patients required further procedures and why? In the first group (rate of 18.9 per cent of revisions), there were four categories of problems. These included: 1) ACL revision (7.7 per cent), 2) cartilage repair or removal (13.3 per cent), 3) scar tissue or fibrosis removal from the joint (5.4 per cent), and 4) problems with the hardware left in the joint (2.4 per cent). In the 10 per cent group who had surgery on the other knee, ACL tears and injuries to the cartilage were the main two reasons for a second surgery.

The majority of patients only had one additional surgery. But there were some individuals who had a second, third, or more surgeries. Further analysis of the data showed that younger patients (younger than 18 years) were more likely to need further surgery. Younger patients with a ruptured ACL may just be more active putting them at increased risk of further problems. Or they may not follow the physician’s and physical therapist’s instructions after surgery. This type of noncompliance could be a factor but was not determined in this study.

One other patient-related factor was mentioned but not studied: the potential for reinjury based on genetic features such as collagen disruption affecting both ligaments and cartilage. A third risk factor (predictor) was the use of an allograft (from a donor rather than from the patient) to reconstruct the damaged ACL. This factor falls under the category of surgical technique (rather than being a patient-related factor).

The authors questioned whether being overweight or female might be other risk factors or predictors of subsequent knee surgeries. But this was not the case in this study. Other studies have reported higher reoperation rates among females.

Additional surgeries cost more money and often lead to decreased patient quality of life and satisfaction. Finding ways to prevent subsequent knee surgery will be the focus of future research efforts. Although age is a nonmodifiable risk factor, the use of allografts will be investigated further. With this information in mind, you can have a frank discussion with your surgeon about your risks and the likelihood of your need for a second (revision) surgery.

Arthroscopic examination and surgery of the knee have become mainstays in the diagnosis and treatment of many different knee problems. But depending on the particular problem, entry of the scope may vary. Many studies have been done to determine the precise approach to use (from the front, side, back or some combination). More posterior arthroscopic procedures are being done now as the surgical techniques and tools have improved over time.

For example, repair and reconstruction of the posterior cruciate ligament can be done using a posterior arthroscopic portal. Likewise, removing loose fragments of cartilage, repairs of avulsion fractures of ligaments, synovectomies, and repairing tears of the posterior horn of the menisci can be done with this posterior technique.

However, every knee is slightly different in shape and the position of vital structures (e.g., blood vessels and nerves may vary from person to person). Depending on the position of the knee and the portal (opening) used, the surgeon can be challenged by the smallest anatomic difference.

And living tissue is dynamic, not static. In other words, these important structures can move during the procedure. That factor alone can increase the risk of damage or injury caused by the arthroscopic technique. So choosing the safest method of entry for the needle used during the arthroscopic procedure is important.

Only a thin layer of fat separates the popliteal artery along the back of the knee from the thin posterior capsule. This can add to the risk of damage during posterior arthroscopic approaches to the knee. Sometimes the surgeon must change the knee position during the procedure. Saline fluid flows through the joint during the procedure and can also push soft tissue structures away from their normal positions.

Entering from the back of the knee, the scope can be placed in a posterolateral, posteromedial, or transseptal position. Posterolateral refers to the back and outside location of the knee. Posteromedial scope placement comes in from the back and inside edge (closest to the other knee).

Transseptal arthroscopic placement describes the passing of the scope from the posteromedial portal through the posterior septum of the knee. The posterior septum is an anatomical structure in the back of the knee. It divides the posterior compartment of the knee into two parts: lateral and medial. It is in the posterior compartment where some of the blood vessels and nerves are located.

There is some evidence that the risk of injury to the popliteal artery and peroneal nerve might be less when the knee is bent more than 90 degrees. Likewise, the risk of damage could be greater the straighter the knee during the arthroscopic procedure.

Studies have shown that the use of MRIs before surgery can aid in preventing injuries during posterior knee arthroscopic procedures. It sounds like your surgeon has taken all of the important factors into consideration when planning your procedure and is proceeding with the appropriate cautionary preliminary steps such as an MRI.

Tears of the meniscus (cartilage in the knee) from degenerative changes are more common in late middle age than in earlier years. The posterior horn of the medial meniscus is especially likely to develop tears as we get older. The medial meniscus is the portion of the cartilage along the inside of the knee joint (closest to the other knee). The posterior horn is located on the back half of the meniscus.

Horizontal meniscal tears (from side to side dividing the posterior horn in two parts) can respond well to conservative care (strengthening program) without the need for surgery. However, treatment choice for this type of meniscal tear is not always easy. These are difficult tears because they can go deep into the joint capsule. Starting with an exercise program as part of a nonoperative approach is a good idea for many patients.

A program designed and supervised by a physical therapist geared toward improving muscle strength, flexibility, and endurance may be advised. Expect to commit at least eight-weeks to the exercise program (including a home exercise portion). The therapist will evaluate your symptoms, motion, posture, strength, alignment, and function. The program will be tailored to your specific needs.

Stretching; isometric, isotonic, and eccentric muscle exercises will be prescribed in a progressive fashion (increasing over time). You can expect pain relief, improved motion and function, and increased activity levels. Most patients report being “very satisfied” with this type of treatment approach. The tear tends to remain stable and no further treatment is required. Only a handful will continue to experience painful symptoms possibly requiring surgical treatment.

Horizontal meniscal tears (from side to side dividing the posterior horn in two parts) are the topic of a recent study from the Center for Joint Disease in Korea. The information they presented may be helpful to you in making the decision between exercise and surgery.

The goal of the researchers (orthopedic surgeons) was to see how patients with degenerative horizontal tears of the posterior horn of the medial meniscus responded to surgical treatment versus conservative care (strengthening program).

Treatment choice for this type of meniscal tear is not always easy. These are difficult tears because they can go deep into the joint capsule. Removing part or the entire meniscus can result in ongoing painful symptoms. A partial meniscectomy eventually leads to a second surgery to remove the entire meniscus (total meniscectomy). Studies also show that partial or total meniscectomy can lead to early arthritis.

All patients included (total of 102) in this study were between the ages of 43 and 62 and experiencing intense knee pain. Mechanical symptoms such as clicking and/or popping were also reported by most of the patients. Two groups were followed for two years after treatment: the surgical (meniscectomy) group and the strengthening (nonoperative) group. Patients were assigned to their group using random selection. There was a four-to-one ratio of women to men (81 women and 21 men).

The exercise group was supervised by a physical therapist as they worked on muscle strength, flexibility, and endurance. Details of the eight-week exercise program (including a home exercise portion) were provided. For the surgical group, arthroscopy was used to remove frayed tissue and smooth the joint surface (partial meniscectomy). One orthopedic surgeon performed all of the procedures. No one had a complete meniscectomy. Everyone in the surgical group participated in the same exercise program as the nonoperative group but without the benefit of a physical therapist’s supervision.

A variety of measurements were used to compare results including pain, knee motion, activity, and patient satisfaction. The statistical analysis showed no difference in outcomes between the two groups. Pain relief, improved function, and very satisfied patients were the final results for both groups. Only a small number of patients in both groups continued to report painful symptoms at the final check-up.

In summary, this study provides evidence that horizontal meniscal tears can be treated successfully with a nonoperative approach. The tear tends to remain stable and no further treatment is required. Previous routine management with arthroscopic partial meniscectomy may not be needed after all.

But even for those who have surgery, rehab afterwards with exercise is usually advised. Fortunately, the exercise program seems to yield long-lasting results. A short-term investment of your time and energy might be well worth it before being subjected to the potential for more serious complications from surgery.

Femoroacetabular impingement, otherwise known as FAI, does not have one symptom or one clinical test that tells the physician, “Yes, this person has femoroacetabular impingement FAI)”. Instead, the diagnosis is one of exclusion based on patient history, clinical symptoms, physical examination, and the results of imaging studies (X-rays, MRIs).

We say the diagnosis is one of exclusion because there are other hip problems with similar presentation. The examining physician formulates the diagnosis by excluding other potential causes in order to make the final determination that the condition responsible for the patient’s symptoms is, indeed, FAI.

Usually the physician begins with the patient history that might tip him or her off that this could be FAI. Here’s where the “exclusion” piece comes in. Because patients with hip pain have a variety of symptoms, questions must be asked to help determine the cause of those symptoms. Was there an accident or injury affecting the hip? Did the person have any hip problems as a child (e.g., slipped capital epiphysis or Legg-Calve-Perthes disease)? Were there any previous surgeries on the hip?

Activity level (especially activities that involve repetitive hip motion) is a key risk factor for FAI, whereas a history of alcohol and steroid use might point more toward something like osteonecrosis (death of bone cells). Labral tears (the labrum is a fibrous rim of cartilage around the hip socket) can cause similar symptoms to FAI (e.g., painful clicking, popping, snapping with hip motion) but is usually associated with a specific injury (often sports-related).

During the physical assessment, the physician uses different tests to determine whether the pain (or other symptoms) is intra-articular (coming from inside the hip joint) or extra-articular (structures around the joint but not inside the joint). Observing how you sit, stand, and walk might provide some additional helpful diagnostic clues. For example, there is a tendency among patients with FAI to sit with a slouched posture to take pressure off the hip.

Imaging studies are also helpful and an important part of the diagnostic process. Change in certain angles of the hip (as measured on X-rays) with no sign of hip dysplasia is diagnostic of deformity associated with FAI. On the other hand, MRI-evidence of labral or other cartilage damage helps rule out FAI as the potential source of symptoms.

Limited hip internal rotation is a red flag for FAI. But most other positive findings only point to the hip as the source of the symptoms, not the actual cause. A positive response to injection of an anesthetic (numbing) agent into the hip can confirm the source of pain. Relief of pain with injection directly into the joint confirms the hip (not lumbar spine or groin) as the true origin of pain. These additional areas where pain can occur with FAI cause some diagnostic confusion.

Since there is no one test, symptom, or clinical finding that confirms a diagnosis of femoroacetabular impingement (FAI), a thorough evaluation is required. With patience and persistence, the orthopedic surgeon can sort through important points in the patient history. Combining that information with findings from the physical examination and imaging studies will be necessary to make the final diagnosis. As we mentioned, the differential diagnosis is often one of exclusion through a process or “ruling out” other hip conditions, one at a time.

It sounds like your physician is following the best practice standard for making an accurate diagnosis of your problem. You may have to be equally patient until all the pieces are put together to solve the puzzle.

As more and more aging Baby Boomers start to develop knee osteoarthritis, researchers are focusing on the whys and wherefores of this condition. As you have found out, studies have already shown that removing a torn meniscus (knee cartilage) puts people at a significantly greater risk of developing knee osteoarthritis later on.

But what happens to those patients who have a torn meniscus that doesn’t get treated? Can the untreated injury also contribute to the development of knee osteoarthritis? That is what remains unclear at this time. It makes sense that a torn meniscus that goes clear down to the bone can disrupt the normal knee joint biomechanics, alignment, and movement. And without a completely normal joint, the risk goes up of joint degeneration and eventual osteoarthritis.

Specific characteristics of meniscal tears also appear to be very important in whether or not the person develops knee osteoarthritis later. For example, the location, severity, and complexity of meniscal damage (as shown on MRIs) are predictive factors.

It has been shown that the larger and more complex the meniscal tear, the greater the likelihood of osteoarthritic changes in that knee. Tears across the meniscus (rather than horizontal tears along the length of the cartilage) were a greater risk factor when the tear went through at least one-third of the meniscus. It is also the case that if more than half of the torn meniscus is observed outside the boundaries of the joint, it is considered “severe” and a risk for the development of OA.

Of course, the next question was: what makes an untreated meniscal tear a risk factor for damage to the joint surface and resultant osteoarthritic changes of the knee joint? It turns out that people who have a meniscal tear of the posterior horn of the meniscus are at increased risk of osteoarthritis developing in that knee. As the name suggests, the posterior horn is the curved section of the meniscus along the very back of the knee.

Having both a posterior horn tear and severe extrusion does not appear to increase the risk of developing OA. However, extrusion seemed to be a risk factor for longer meniscal tears. These two combined together are seen more often in the patients who did develop osteoarthritis.

Once risk factors (such as meniscal tears) for osteoarthritis (OA) are identified, treatment that will yield the best results can be determined. Not all meniscal injuries result in OA, so efforts to find the most significant characteristics of meniscal injuries are important.

For now, it looks like complex tears, meniscus that extrude out of the joint, and injuries that are wider and/or longer than one-third of the meniscus are present in patients who develop X-ray evidence of osteoarthritis later.

Once a ligament is torn, it does not repair or heal itself. Normal strength and durability do not return without reconstruction of the ligament and that requires a tendon graft to replace the ruptured tendon.

There are many different ways to reconstruct the damaged ligament. For the anterior cruciate ligament inside the knee, there are two main choices: the patellar tendon graft that you had and the alternate: hamstring tendon graft.

There are pros and cons to each one of these. Neither one is perfect yet. Attaching the graft in place (called fixation) creates problems of its own. In particular, finding a place to attach the hamstring tendon graft to the bone is a challenge. That’s one reason why surgeons choose the patellar tendon over the hamstring tendon for the graft. It’s also one reason why they are looking for ways to do the reconstruction procedure that yield better results with fewer problems and a lower failure rate.

Other treatment approaches that have fewer limitations and fewer adverse effects are under investigation. For example, scientists are exploring tissue engineering, the use of growth factors, bone morphogenetic protein (BMP), and other types of cells in ACL reconstructive surgery.

The use of donor grafts from animals known as xenografts (e.g., from calf skin or calf small intestine) is one area of intense study. But these are not readily available as yet. Efforts to develop an artificial ligament (also referred to as a ligament-augmentation device) have not been successful as yet either. Such a system could help patients heal and rehab faster but may not be as strong or as resilient as natural tissue.

There may be some things that can be done about the appearance of your scar. Although it will fade over time, application of vitamin E oil is recommended by some to soften the scar tissue. A physical therapist trained in techniques such as myofascial release can also assist in keeping the scar and surrounding soft tissues flexible. Preventing scarring from binding the tissue and causing puckering can also aid in movement and appearance.

The stiffness may resolve over time but should be re-evaluated by your surgeon. This may be something that can be addressed by your physical therapist as well. Don’t hesitate to make a follow-up visit with your surgeon to review both of your concerns.

As you have discovered, right now the “gold standard” for reconstructive surgery of the anterior cruciate ligament (ACL) is graft replacement of the ruptured tendon. The surgeon uses either a piece of the patient’s patellar tendon or hamstrings tendon. Tiny tunnels are drilled through the bone to secure and attach the graft tissue.

But for as many advantages as there are to these graft options, there are just as many disadvantages. The disadvantages are the reason researchers continue to look for other treatment approaches that have fewer limitations and fewer adverse effects. Tissue engineering, the use of growth factors, bone morphogenetic protein (BMP), and other types of cells in ACL reconstructive surgery remain under investigation.

This topic is of interest to both medical and veterinary surgeons as humans and animals experience ACL damage requiring surgery. In a recent review article from the School of Veterinary Medicine in Shiraz, Iran, veterinarians presented an update on graft selection in ACL reconstruction and efforts to improve bone tunnel healing. They discuss past treatment choices, current strategies, and reflect upon future approaches.

The authors provide a nice summary in table form of the advantages and disadvantages of three graft types used in ACL reconstruction (autograft, allograft, artificial or xenograft). After giving an in-depth discussion of each type, they briefly summarize the pros and cons of each one.

For example, patellar tendon grafts are thicker and therefore stronger (biologically and mechanically) compared with hamstring tendon grafts. But the patellar tendon graft leaves a more unsightly and visible scar and they are slower to incorporate into the body and heal. Because the graft tissue is taken from the soft tissues that help extend (straighten) the knee, there can be a negative effect on the knee extensor mechanism.

Patellar tendon grafts harvest easily so the time in surgery is less but the cost is higher compared with hamstring tendon grafts. Potential surgical and post-operative complications include patellar fracture, patellar tendinopathy, knee pain, and patellar crepitus (crunching or clicking of the patella as it moves up and down over the knee).

Hamstring tendon grafts (when taken from the patient) have a higher rate of problems at the donor site. But rehabilitation is less intensive compared with patellar tendon grafts. On the plus side, there are no obvious scars at the donor site making them more pleasing cosmetically. Attaching the graft (called fixation) can be a challenge.

Patients who have hamstring tendon grafts can lose some of the function of the hamstrings. The end-result may be less than a full return to all activities. Graft failure and rupture at the bone tunnel site occurs more often with hamstring tendon grafts. So does degenerative joint disease several years down the road.

Knee joint laxity is reported more often with hamstring tendon grafts compared with patellar tendon grafts. This may be because there is more elasticity in the hamstring tendon compared with the stiffer patellar tendon.

So — which one to choose? As you can see, there are different factors to consider. Your surgeon is really the best one to advise you in this area. Your particular situation and his/her preferences are usually the final determinants in this decision. Hopefully, the information provided here will help you find the right questions to ask your surgeon to aid you in making this decision.

As you might expect, athletes make up a very large part of the patients who end up needing anterior cruciate ligament (ACL) surgery. And with 200,000 cases reported each year, it is not that uncommon to find patients like yourself who experience a failed result and potential need for another surgery.

For the most part, surgery to reconstruct the torn ligament is quite successful. But studies do show up to a 10 per cent failure rate after the primary (first) surgery. A recent report by surgeons from the Mayo Clinic in Rochester, Minnesota may be of interest to you. They tell us about the results for patients who have two or more ACL surgeries.

Repeat or revision surgery for ACL reconstruction is often needed because the tunnels drilled through the femur (thigh bone) for the graft tissue to go through are placed too far forward the first time. In other cases, damage to the cartilage on the surface of the knee joint and misalignment of the lower extremity contribute to failure of the primary (first graft) procedure.

Looking back over the records of patients who had at least two ACL reconstructions at the Mayo Clinic, they found a total of 15 charts. The patients ranged in ages from 18 up to 57. Two-thirds of those cases required new femoral tunnels. Two-thirds had severe chondral (cartilage) lesions. And three-fourths had a meniscal tear.

As it turned out, the first two factors (placement of the femoral tunnels and chondral lesions) were risk factors for graft reconstruction failure. The third factor (damaged meniscal cartilage) was not directly linked with graft failures. A graft failure was defined as a rupture of the graft tissue or knee joint instability. Another risk factor for a failed ACL reconstruction was obesity. Patients with a body mass index (BMI) measure of 29 or higher had fair to poor results after the first surgery.

ACL revision of primary reconstructions can be a difficult and challenging surgery. There are many factors to consider including a limited choice of graft tissue, fixing the graft in place to create a stable response, unusual/unnatural anatomy, and difficulty finding the right spot and then creating correct tunnels for the final step of the initial surgery.

But according to this study from the Mayo Clinic, good-to-excellent results are possible even after repeated ACL surgical revisions.

Up to 10 per cent of all patients who have a primary (first) reconstruction of the anterior cruciate ligament (ACL) will experience a failed result. This could mean the graft failed/re-ruptured or it could mean the knee joint remained unstable after the reconstructive surgery.

Experts from the Mayo Clinic in Rochester, Minnesota suggest three reasons for ACL reconstructin failure. First, there can be post-operative complications such as infection, swelling, failure of the wound to heal, or failure of the graft “to take”.

Second, there can be problems with the way the surgery was done. For example, tunnels are drilled through the lower aspect of the femur (thigh bone). The new graft material is passed through these tunnels and then attached to the bone. If the femoral tunnels are drilled too far forward or too far back, the angle of pull can be off, eventually leading to biomechnical problems and even graft failure.

And third, there can be some anatomic reasons for the less-than-satisfactory results. The alignment of the lower extremity may be a significant factor. In fact, malalignment of the leg results in uneven wear and tear on the joint. Damage to the meniscal or hyaline cartilage can contribute to the rupture of a primary ACL reconstruction.

There may or may not have been anything you did wrong that contributed to this unfortunate series of events. When patient factors are significant, it’s usually one of several reasons. Overuse and trauma from participation in sports activities can be a major contribution. Patient noncompliance (failure to follow the surgeon’s and the physical therapist’s directions) is a potential risk factor for failure. And finally, according to a recent report from the Mayo Clinic, patients who are overweight (body mass index of 29 or higher) are more likely to rupture an ACL repair or reconstruction.

Your concerns are well-founded given that one in 10 patients who have ACL reconstructive surgery are going to have significant problems. Talk with your surgeon about your situation, your risk factors, and what you can do to prevent further complications in the future.

For sure (but not always)! A recent study compared two groups of patients: those who had no osteoarthritis (OA) in one knee but who later developed osteoarthritis (group one) and those who did not develop OA at all. Everyone in the two groups was in the study because they had OA in one knee but not the other. It was the uninvolved knee that these researchers paid close attention to.

X-ray evidence was used to determine who had osteoarthritis (OA) in the first place and that it was only present in one knee. X-rays were also used to diagnosis the new onset of OA in the knee that previously was healthy without signs of joint change typical of OA (e.g., joint space narrowing, cartilage defects, changes in bone size).

They used a knee osteoarthritis database called the Knee Osteoarthritis Initiative (OAI). This database contains information collected on patients between the ages of 45 and 80 years of age who were treated at one of four participating centers.

Once they saw who developed osteoarthritis and who didn’t, they looked for differences between the two groups that might be considered risk factors for the development of OA. One of those variables was the presence of meniscal damage. MRIs were used to look for tears and helped in classifying the type, direction, and size of the tear(s). Size was measured in terms of length, width, and depth. They also measured how much the meniscus extruded (or protruded) out from inside the joint.

They found that the larger and more complex the meniscal tear was the greater likelihood of osteoarthritic changes in that knee. Tears across the meniscus (rather than horizontal tears along the length of the cartilage) were a greater risk factor when the tear went through at least one-third of the meniscus. It was also the case that if more than half of the torn meniscus was observed outside the boundaries of the joint, it was considered “severe” and a risk for the development of OA.

Of course, the next question was: what makes an untreated meniscal tear a risk factor for damage to the joint surface and resultant osteoarthritic changes of the knee joint? It turns out that two-thirds of the patients who had a meniscal tear and then developed OA had an injury of the posterior horn of the meniscus. As the name suggests, the posterior horn is the curved section of the meniscus along the very back of the knee.

Having both a posterior horn tear and severe extrusion did NOT increase the risk of developing OA. However, extrusion seemed to be a risk factor for longer meniscal tears. These two combined together were seen more often in the patients who did develop osteoarthritis.

The authors concluded by saying that not all meniscal injuries result in OA, so their efforts to find the most significant characteristics of meniscal injuries are important. For now, it looks like complex tears, meniscus that extrude out of the joint, and injuries that are wider and/or longer than one-third of the meniscus were present in patients who developed X-ray evidence of osteoarthritis later.

With more and more older adults getting knee joint replacements, the risk of deep joint infection becomes a concern. It is one complication that can put the entire knee (and new joint) at risk and is the number one reason for additional surgery.

You asked, how often does it happen? Why does it happen? And what can be done about it? Those are the three questions raised and answered in a recent study from the very large and very well-known Kaiser Permanente health care system in California. They reviewed the medical records of the 56,216 patients who had a total knee replacement at any one of their hospitals. They collected information from the charts about the patients, the diagnosis, the surgeon, the surgery, and the hospital.

The first question they asked (and answered) was: how often does this happen? Turns out that about 0.72 per cent of the total 56,216 patients developed the kind of deep joint infection being studied. And this rate was very close to what has been reported in other similar studies.

After analyzing all the data, they were able to identify some specific patient and hospital risk factors. They also pointed out some protective factors that might be used in the future to reduce the number of deep joint infections. Some risk factors for postoperative infection are modifiable (something can be done to change the risk) while others are nonmodifiable (cannot be changed).

For example, they found that patients of a Hispanic background actually have a lower risk of infection after joint replacement. On the other hand, men have a much higher risk compared with women. But obviously, there isn’t anything that can be done to change these two (nonmodifiable) risk factors except warn the patients of the possibilities.

Age (young versus old) does not seem to make a difference but body mass index (BMI) and diabetes both increase the risk of deep infection following knee joint replacement. These are considered modifiable patient-related risk factors. There were also a few surgical-related risk factors such as longer operative time and the use of antibiotic-laden cement.

Protective surgical factors include lower annual hospital volume (fewer patients seen each year) and having both knees replaced at the same time. Bilateral knee replacement is preferred by a smaller number of select patients who must be pre-approved for this procedure by their physician.

This very large study included patients of many different ages, races, and characteristics. The results offered some insight into the problem of (and solutions to) deep joint infection after a knee replacement. Overweight patients who have diabetes and men should be advised that their risk of infection is increased by these factors.

Exactly what went wrong for your aunt may be found in these known risk factors. But some patients who develop joint infection have no known risk factors so it can remain a mystery. The key to successful recovery is early recognition and treatment of the problem. It sounds like she is getting the care she needs now.

Researchers at the very large and very well-known Kaiser Permanente health care system in California conducted a recent study that may offer you some helpful information. They reviewed the medical records of 56,216 patients who had a total knee replacement in their health-care system. They collected information from the charts about the patients, the diagnosis, the surgeon, the surgery, and the hospital.

The first question they asked (and answered) was: how often does this happen? Turns out that about 0.72 per cent of the total 56,216 patients developed the kind of deep joint infection being studied. And this rate was very close to what has been reported in other similar studies.

After analyzing all the data, they were able to identify some specific patient and hospital risk factors. They also point out some protective factors that might be used in the future to reduce the number of deep joint infections. Some risk factors for postoperative infection are modifiable (something can be done to change the risk) while others are nonmodifiable (cannot be changed).

For example, they found that patients of a Hispanic background actually have a lower risk of infection after joint replacement. On the other hand, men have a much higher risk compared with women. But obviously, there isn’t anything that can be done to change these two (nonmodifiable) risk factors except warn the patients of the possibilities. And not all men get infections so this one factor isn’t the whole story.

Age (young versus old) does not seem to make a difference but body mass index (BMI) and diabetes both increase the risk of deep infection following knee joint replacement. These are considered modifiable patient-related risk factors. There were also a few surgical-related risk factors such as longer operative time and the use of antibiotic-laden cement.

Protective surgical factors include lower annual hospital volume (fewer patients seen each year) and having both knees replaced at the same time. Bilateral knee replacement is preferred by only a small number of select patients who must be pre-approved for this procedure by their physician.

In conclusion, this very large study including many different ages, races, and patient characteristics offered some insight into the problem of (and solutions to) deep joint infection after a knee replacement. Overweight patients who have diabetes and men should be advised that their risk of infection is increased by these factors.

We do not provide that type of on-line service but we can tell you there was a recent article published in a well-known orthopedic journal from that area. Specifically, one surgeon from the Saumya Orthocare: Centre for Advanced Surgeries of the Knee Joint in Ahmedabad, India conducted a study of 32 patients with chronic patellar insufficiency (i.e., the knee cap kept dislocating).

In this study, the superficial quad technique was used as the graft to replace the ruptured medial patellofemoral ligament (MPFL). The quadriceps muscle is the large four-part muscle along the front of the thigh. The quadriceps tendon attaches to and around the patella.

The MPFL is the stabilizing ligament that helps keep the patella (knee cap) tracking up and down over the knee. When the patella is dislocated, this ligament is almost always ruptured. And once a ligament is torn, it does not repair or heal itself. Chronic, recurrent patellar dislocation with MPFL rupture is referred to as medial patellofemoral insufficiency.

In order to regain patellar stability and prevent repeated dislocations (ligament insufficiency leading to patellar instability), (surgical) reconstruction is needed. There are many different ways to reconstruct the damaged ligament. Most techniques involve a tendon graft to replace the ligament. Attaching the graft in place (called fixation) creates problems of its own. That’s one reason why surgeons are looking for better ways to accomplish the reconstruction procedure.

If, in fact, you had a superficial quad technique to repair a torn medial patellofemoral ligament, you will likely experience good results. According to the Indian surgeon who is developing and investigating this surgical approach to patellar insufficiency, there are five advantages or “plusses” to this new technique.

First, the graft is a better anatomic match to the original medial patellofemoral ligament (MPFL) in terms of width, breadth, and length. The natural or native MPFL is thin, broad, and sheet-like; so is the quadriceps slip used in this procedure. Two, the superficial quadriceps tendon graft is not as stiff as the commonly used hamstring tendon graft. A strong, stiff graft puts more load on the patellofemoral joint and can cause patellar fracture later.

Three, the superficial quadriceps graft does not have to be held in place with screws or wires. This makes it possible to attach the graft to the medial border of the patella where the MPFL is located normally. The result is a more accurate re-creation of patella biomechanics and elimination of complications from patellar fixation. This is helpful because most common problems that develop after MPFL reconstruction can be traced back to either the type of graft material or the way in which the graft is held (i.e., fixation technique used) in place.

Four, the graft can be harvested arthroscopically with a very small incision. And five, at least in the short-run (first three years), the results are equal to outcomes when compared with using the hamstring tendon.

In the published article, the surgeon described and displayed photographs of the 10-steps of this surgical technique. Your therapist may want to take a closer look at this information.

The author begins with arthroscopic examination to assess all injuries and damage inside and around the knee joint. Graft harvest, preparation of the graft, and attachment of the graft are part of steps two through eight. The final steps involve getting the most optimal graft length and then repairing any other soft tissue injuries (e.g., medial retinaculum).

In the follow-up of these 32 patients, no one had recurrent patellar dislocations or other patellar complications. One-fourth of the group had problems bending the knee fully and went to physical therapy to resolve the issue. The author suggested that future improvements of the superficial quadriceps procedure (e.g., better fixation points at the femur, elimination of scarring, better arthroscopic techniques) may help prevent this complication and further improve results.

In addition to reviewing this article, you may want to see an orthopedic surgeon locally for follow-up. He or she can initiate contact with the surgical center in India where you were treated to obtain more information.

There is a stabilizing ligament known as the medial patellofemoral ligament or MPFL that helps keep the patella (knee cap) tracking up and down over the knee. When the patella is dislocated, this ligament is almost always ruptured. And once a ligament is torn, it does not repair or heal itself. Chronic, recurrent patellar dislocation with MPFL rupture is referred to as medial patellofemoral insufficiency.

In order to regain patellar stability and prevent repeated dislocations (ligament insufficiency leading to patellar instability), (surgical) reconstruction is needed. As you are finding out, there are many different ways to reconstruct the damaged ligament. Most techniques involve a tendon graft to replace the ligament. Attaching the graft in place (called fixation) creates problems of its own. That’s one reason why surgeons are looking for better ways to accomplish the reconstruction procedure.

You are indeed correct that all around the world, surgeons are working to find better ways to reconstruct the medial patellofemoral ligament (MPFL). We reported on a previous study from China on this topic. Now there is another from India dealing with the type of graft you mentioned called the Superficial Quad Technique.

In a study from the Saumya Orthocare: Centre for Advanced Surgeries of the Knee Joint in India, one surgeon investigated the use of the superficial quad technique. A superficial slip of the quadriceps tendon is used as the graft. The quadriceps muscle is the large four-part muscle along the front of the thigh. The quadriceps tendon attaches to and around the patella. There are five advantages or “plusses” to this new technique.

First, the graft is a better anatomic match to the original medial patellofemoral ligament (MPFL) in terms of width, breadth, and length. The natural or native MPFL is thin, broad, and sheet-like; so is the quadriceps slip used in this procedure. Two, the superficial quadriceps tendon graft is not as stiff as the commonly used hamstring tendon graft. A strong, stiff graft puts more load on the patellofemoral joint and can cause patellar fracture later.

Three, the superficial quadriceps graft does not have to be held in place with screws or wires. This makes it possible to attach the graft to the medial border of the patella where the MPFL is located normally. The result is a more accurate re-creation of patella biomechanics and elimination of complications from patellar fixation. This is helpful because most common problems that develop after MPFL reconstruction can be traced back to either the type of graft material or the way in which the graft is held (i.e., fixation technique used) in place.

Four, the graft can be harvested arthroscopically with a very small incision. And five, at least in the short-run (first three years), the results are equal to outcomes when compared with using the hamstring tendon.

In the follow-up of the 32 patients in this particular study, no one had recurrent patellar dislocations or other patellar complications. One-fourth of the group had problems bending the knee fully and went to physical therapy to resolve the issue. The author suggests that future improvements of the superficial quadriceps procedure (e.g., better fixation points at the femur, elimination of scarring, better arthroscopic techniques) may help prevent this complication and further improve results.

The knee cap or patella is a marvelous and complex structure. Held over the knee joint by soft tissue structures, it moves or “tracks” up and down with knee motion. Anatomists are still exploring and learning how the patellar tracking mechanism really works. Understanding normal patellar anatomy and kinematics (movement) will help surgeons repair and restore this part of the knee when injury leads to chronic, painful patellar dislocations like you have.

Studies have now shown that this soft tissue structure blends with a portion of the medial patellofemoral ligament (MPFL). The two structures work together to keep the patella in the center of the knee as it starts tracking during knee flexion. Right now, there is no agreement or consensus on the best way to reconstruct a torn medial patellofemoral ligament (MPFL) in order to restore patellar stability.

The use of suture anchors, bone graft material, and making tunnels through the bone to attach soft tissue grafts are currently under close investigation. In fact, a new surgical technique for the problem of recurrent patellar dislocation has recently been developed and reported on.

The new Y-graft technique is designed to help restore the knee to as close to normal anatomy after recurrent dislocations. Early results show that it has the strength needed to hold the kneecap in place during movement requiring patellar tracking up and down over the knee. The Y-graft outperformed the more commonly used C-graft technique.

The basic difference is in the shape of the graft tissue and the fixation sequence. Fixation sequence refers to how and when the two ends of each graft are attached. For example, the C-graft procedure attaches both ends to the femur (lower leg bone) at the same time. Tension on the two ends of the graft is set at the same time.

The Y-graft technique allows the surgeon to apply tension to the separate ends one at a time with the knee in zero degrees of flexion (i.e., straight) and then at 30 degrees of flexion. This separate graft tensioning helps mimic the more normal anatomy (alignment) and kinematics (movement). A special table summarizing the differences between these two fixation methods is also provided to help surgeons understand how the two techniques compare.

Results comparing two patient groups with chronic, painful patellar dislocations (one group had the Y-graft, the second group had the C-graft) were measured using clinical tests and CT scans. Knee function, patellar stability, and patellar angles were the main outcome measures. With regular follow-up for two years, they found that the Y-graft did provide better knee function compared with the C-graft. And the Y-graft (double-bundle technique) restored normal patellar tracking much better than the C-graft (single-bundle technique).

Further follow-up is needed now because recurrent patellar dislocations tend to develop more as time goes by. We don’t know if this was one of the ways your surgeon suggested for you. But knowing a little bit about each method can help you better understand what your surgeons are recommending and what might work best for you.

Your postoperative rehabilitation program will be highly dependent on the surgical technique used to reconstruct the soft tissue structures. The patella or kneecap is a very complex structure. Anatomists are still exploring and learning how the patellar tracking mechanism really works (i.e., how the kneecap moves up and down over the knee joint).

Understanding normal patellar anatomy and kinematics (movement) will help surgeons repair and restore this part of the knee when injury leads to the type of chronic, painful patellar dislocations you may be experiencing.

Many times, the medial patellofemoral ligament (MPFL) is torn and becomes the focus of repair or reconstruction. This soft tissue structure provides passive restraint (holds the patella in place) as the kneecap moves during the first 30 degrees of knee flexion. There are different ways to reattach (repair) this soft tissue structure. After so many recurrent dislocations, the tissue may be too damaged to repair. That’s when graft tissue is used to reconstruct the tissue.

So, once again, rehab will be determined based on the procedure performed and surgeon preferences. Most likely, you will begin with isometric exercises of the quadriceps muscle (large muscle along the front of the thigh that attaches around the kneecap). Isometrics means the leg won’t actually move while you contract the muscle.

You will be instructed by a physical therapist in how to perform isometrics, especially including straight-leg raises (lifting the straight leg up). You will be doing these exercises throughout the first hours and days following surgery.

You may be allowed to put partial weight on that leg while wearing a splint or brace holding the knee in full extension. This will protect the healing soft tissue structures. The therapist will show you how to use a pair of crutches safely, efficiently, and effectively while walking.

In a few days after surgery, you may be allowed to start range-of-motion exercises. Gradually each component of rehab will be progressed. Around three months postop, you will be allowed to exercise (e.g., fast walking, jogging). When you have sufficient motion, strength, and stability, then full activities are once again allowed. If you are an athlete (especially one who is hoping to return to full sports participation), then an additional rehab focus will be added to prepare you for your specific sport requirements.

Again, all of these things are variable depending on multiple factors. These can include the type of surgery you have, any complications or problems that might develop, surgeon preference, and your own personal goals, attitudes, and approach to recovery.

It just so happens that the first ever study comparing the results of these two treatments (and specifically for athletes with “Jumper’s Knee”) was recently published. We can share the results with you and that may help you formulate your own opinions and direct your path.

Running and jumping over and over often leads to this condition in athletes known as patellar tendinosis or jumper’s knee. Pain along the front of the knee during the activity that goes away with rest is a cardinal symptom of this condition. Dancers, gymnasts, and basketball, soccer, and volleyball players like yourself are affected most often.

As you have been told, jumper’s knee goes away when the muscles along the front of the knee (extensor mechanism) that pull across the patella (kneecap) stop pulling. It is a self-limiting, self-resolving condition. Therefore, the first recommended treatment is always to stop overloading the extensor mechanism. Rest, anti-inflammatory medications, and specific exercises under the supervision of a physical therapist are advised.

But many athletes (for various reasons including scholarship pressures) work through the pain until conservative (nonoperative care as described above) is no longer successful in reducing pain. At that point other treatment options are considered. In the study we mentioned, sports medicine experts compared two treatment approaches for chronic tendinopathy of the extensor mechanism: 1) platelet-rich plasma (blood injection therapy) and 2) extracorporeal shock wave therapy (ESWT).

Platelet-rich plasma (PRP) refers to a sample of serum (blood) plasma that has four (up to 10) times more than the normal amount of platelets and growth factors. This treatment enhances the body’s natural ability to heal itself and is used to improve healing and shorten recovery time from acute and chronic soft tissue injuries. The group of athletes in this study who received PRP were given two injections over a two week period.

Extracorporeal shock wave therapy (ESWT) is a way to generate sound waves outside the body that can be focused at a specific site within the body (in this case, the knee). This treatment technique is also referred to as pressure or sound wave therapy. It is a noninvasive, outpatient procedure.

Pressure waves travel through fluid and soft tissue to sites where there is a change in tissue density. A common interface is where the soft tissues meet bone. A special device delivers shockwaves to the target point where treatment is needed. The shockwaves break down scar tissue that has built up. The body’s repair mechanisms are stimulated to promote healing. New blood vessels develop in the injured area to help jump start the healing process. Three sessions of ESWT were delivered to the second group in this study in 48- to 72-hour intervals.

Both treatments focus on the failed healing of the overused tendon by promoting cell growth, release of growth factors, and improving tissue remodeling. In comparing the two groups responses to treatment, they found everyone in both groups had significant improvements throughout the follow-up time period.

At the end of two months, there was no real difference between the two groups. But later (at the six-month and one-year recheck), the platelet-rich plasma (PRP) injection group pulled ahead with significantly better improvement. Significantly more athletes in the PRP group (compared with the shock therapy group) were also able to return to full sports participation (at a level equal to before their injury).

As this study showed, both are effective in the short term but platelet-rich plasma may have better mid-term results. Further study is needed to asses long-term results. But something you should know is that these athletes were NOT allowed to continue participating in their chosen sports activities. During the treatment, they were given a stretching and strengthening program and then started on water activities if and when they had only mild (or no) discomfort.

Only after four weeks were they allowed to GRADUALLY return to their previous level of training. And only if there was no (or only mild) pain. Full activity was resumed when they could do so pain free. Athletes in other studies who had shock wave therapy and who did not improve were the ones who continued training/playing at their usual and customary level. Healing cannot occur when there is continued, unrestricted load on the healing tendon. Whatever treatment decision you make, keep in mind that soft tissues must be given enough time to recover!

Running and jumping over and over often leads to a condition in athletes known as or jumper’s knee (also known as patellar tendinosis. Pain along the front of the knee during the activity that goes away with rest is a cardinal symptom of this condition. Dancers, gymnasts, and basketball, soccer, and volleyball players are affected most often.

There is a simple treatment for this problem. Jumper’s knee goes away when the muscles along the front of the knee (extensor mechanism) that pull across the patella (kneecap) stop pulling. It is a self-limiting, self-resolving condition. Therefore, the first recommended treatment is always to stop overloading the extensor mechanism. Rest, anti-inflammatory medications, and specific exercises under the supervision of a physical therapist are advised.

If a conservative plan of care fails to yield the desired results, then other options may be considered such as extracorporeal shock wave therapy (ESWT). ESWT is a way to generate sound waves outside the body that can be focused at a specific site within the body (in this case, the knee). This treatment technique is also referred to as pressure or sound wave therapy. It is a noninvasive, outpatient procedure.

Pressure waves travel through fluid and soft tissue to sites where there is a change in tissue density. A common interface is where the soft tissues meet bone. A special device delivers shockwaves to the target point where treatment is needed. The shockwaves break down scar tissue that has built up. The body’s repair mechanisms are stimulated to promote healing. New blood vessels develop in the injured area to help jump start the healing process.

Another newer approach to the problem of Jumper’s Knee is a blood injection therapy called platelet-rich plasma or (PRP). PRP refers to a sample of serum (blood) plasma that has four (up to 10) times more than the normal amount of platelets and growth factors. This treatment enhances the body’s natural ability to heal itself and is used to improve healing and shorten recovery time from acute and chronic soft tissue injuries.

Both treatments focus on the failed healing of the overused tendon by promoting cell growth, release of growth factors, and improving tissue remodeling. Both have been shown effective in the short term (e.g., first two months) but platelet-rich plasma may have better mid-term results. Further study is needed to assess long-term results. You may want to discuss both of these treatment options with your orthopedic surgeon and find out what might be best for you given your particular circumstances.

Many studies show the benefit of exercise for people with knee osteoarthritis. But pounding the pavement (or treadmill) can increase pain as you have noticed. Aquatic therapy in a pool of warm, supportive water is one way to get the needed exercise without the added stress.

In a recent study from the University of Florida, the effects of walking on a treadmill underwater were compared with walking on a land treadmill. It was a small study with 14 adults in ages ranging from 43 to 64. All participants had been formally diagnosed with knee osteoarthritis (OA). A few had OA of the hip or ankle as well.

Everyone was treated with a 20-minute session on a treadmill at zero incline (flat). The 20-minute period was broken into four stages each lasting five minutes. Pace or speed of walking increased slightly with each stage. By the last five minute segment, the patients were walking at a moderate-to-somewhat hard level of perceived exertion.

Three sessions were completed in one week on the aquatic treadmill with water temperature holding steady at 86 degrees Fahrenheit. Then there was a one-week rest period and the same protocol was used on a land treadmill. Some patients did the land treadmill the first week while others were assigned to the aquatic treadmill first. Who did what first was randomly assigned using a computer program.

Aquatic treadmill walking has also been shown to decrease the impact on the knee. The buoyancy of the water reduces the force from the ground starting at the foot and traveling up to the knee (called the ground reaction force). In the study mentioned, it was hypothesized that decreasing the joint load by using an aquatic treadmill would reduce pain and improve exercise quantity and quality. Let’s see if that is what happened for those patients.

Results were measured within 24 hours of completing the three sessions (on either treadmill). They used two main outcomes: change in pain level and joint kinematics. Kinematics refers to how the joints move (speed or velocity, joint angle, step length, step rate).

Changes in pain and kinematics can affect a person’s gait (walking) pattern. Joint kinematic measurements were taken while the patients walked on land in a biomechanics lab. The researchers measured angular velocity for knee extension during stance (weight on that leg) and knee extension and internal rotation during swing (leg moving forward).

The angular velocities measured did improve more after aquatic therapy. Angular velocity gain for left knee extension during stance improved significantly (38 per cent) after aquatic walking. Gain for knee internal rotation was 65 per cent and 20 per cent improved for knee extension during leg swing. Pain was significantly greater (100 per cent more) after land exercise. The number of steps taken and the length of steps did not change with either form of exercise.

The authors pointed out that these kinds of changes in angular velocity indicate that the pattern of movement of the arthritic knee is improved during walking. That is important for restoring normal gait (walking), improving balance, and preventing falls. The actual mechanism for increasing angular velocity and joint kinematics remains unknown. It is thought that the combination of increase in fluid resistance, warmth and pressure of the water, and unloading of the joints work together to create these beneficial effects.

With only three sessions each (aquatic and land) on the treadmill, these outcomes are considered short-term. But evidently there was enough effect on the neuromuscular system to create these changes. Future research will be needed to see if the changes last (and for how long) and whether a longer period of time with more sessions would enhance the benefits even more.

The authors concluded that aquatic therapy may be a good alternative to walking on land for patients with painful and limiting knee osteoarthritis. This treatment approach can help patients experience pain relief and improve walking ability. Why don’t you give it a try (say three sessions) and see how you feel afterwards and if the extra self-care is worth the time for you.