News Category: Knee

Arthroscopic surgery isn’t always better than nonoperative care. That may be especially true in the case of traumatic patellar (kneecap) dislocations. In this study, surgical treatment for primary (first time) patellar dislocation is discussed. Two treatment options were included: arthroscopic and conservative (nonoperative) care. The advantages and disadvantages of each are reviewed. The long-term results (after seven years) are reported.

Patients included were military recruits from the Finish (Finland) army. Most of the patients were young men (ages 19-22) with just a few women included. All had an acute lateral patellar dislocations. The injury occurred during a sports activity or during military training. Lateral means the kneecap moved away from the midline (toward the outside of the knee). When that happens, the structures along the medial (inside) of the knee are often torn or damaged.

In particular, the medial patellofemoral ligament (MPFL) is usually injured. Studies have shown that half the restraining force holding the kneecap in place comes from the MPFL. Successful treatment must address the condition of the MPFL. If it’s torn and is not repaired, then the chances of recurrent patellar dislocation increase dramatically.

Successful outcomes may depend on the type of surgery performed. Arthroscopic repair reduces the risk of injuring blood vessels and nerves in the knee. And any loose fragments of bone, cartilage, or meniscus can be removed easily.

But complete rupture of the MPFL at its femoral attachment may not be seen and cannot be restored fully by arthroscopic surgery alone. There may be other soft tissue injures that remain unidentified with arthroscopic repair. The surgeon relies on MRIs to help identify the location and extent of soft tissue damage.

The military recruits were divided in two groups. Group 1 had an acute arthroscopic repair of the medial retinaculum. The medial retinaculum is a band of connective tissue along the inside of the knee that is holding the kneecap in place. At the same time, the lateral retinaculum was released (cut) to reduce the pull from the opposite side of the knee. This arthroscopic stabilization technique was done within seven days of the injury. Details of the surgery and post-operative care were provided.

Group 2 had nonoperative care. Any large loose fragments of bone or cartilage or hematomas (pockets of blood) were removed to relieve pain. Arthroscopy was used to remove any loose bodies but no other repairs were made. Aspiration technique (needle inserted into the joint) was used to remove swelling from bleeding inside the joint.

Nonoperative care consisted of a knee brace with limited knee flexion for three to six weeks and a rehab program supervised by a physical therapist. Range-of-motion and strengthening exercises were prescribed but these weren’t any different than what the operative group performed.

With nonoperative care, there is a concern for and history of recurrent (second or third) patellar dislocations. Painful instability with partial dislocation called subluxation of the patella may be the end-result of nonoperative care. But without a study of this type, it would be difficult to tell if surgery improves the outcomes or not. In today’s world of evidence-based medicine, we no longer assume surgery to repair the damage would have better results compared with conservative care.

And, in fact, the authors report that the redislocation rate was not significantly different between the two groups. This suggests that 1) surgery doesn’t add value or a benefit over nonoperative care or 2) the condition of the MPFL is more important in patellar stability than was previously recognized.

They did find that patients who had arthroscopic repair were able to return to their preinjury level of physical activity more often than those who were treated conservatively. In a military setting, that may be an important finding.

The authors suggest several factors that may have affected results in this study. First, failure to find and fix MPFL abnormalities may be the real key to success after lateral patellar dislocations. Second, this type of repair may not be appropriate for all traumatic MPFL injuries. For sure, they report that an MPFL rupture where it attaches to the femur (thigh bone) cannot be repaired arthroscopically from inside the joint. A different type of surgical procedure is needed.

One of the weaknesses of this study was the fact that not all patients had X-rays or MRIs done. There were various reasons for this, but it affected the authors’ ability to compare results equally between those who did have the imaging studies done and those who didn’t.

The fact that there were so few women in the study makes this more of a summary of treatment for men. And the equal rate of recurrent dislocations between the groups may be linked with the high levels of activity required of a group of military recruits. So, the results may only be applicable to athletes, soldiers, or highly active young adults.

Their final conclusion was that arthroscopic patellar medial retinacular repair may not be any more successful than nonoperative care in young, active, males with traumatic patellar dislocation. The stabilizing procedure does not guarantee that another dislocation won’t happen. The advantages of arthroscopic surgery in such cases (faster return to work, better cosmetic results, less damage to soft tissues) may make this a better choice than open stabilizing procedures.

Full-thickness cartilage defects (down to the bone) in the knee come with two major problems. First, cartilage doesn’t heal well. Second, treatment often results in failure. One of the newer treatment options is autologous chondrocyte implantation (ACI). It works well, but it is limited to younger patients. Older adults (45 years old and older) have been excluded from this approach — until now.

This report suggests that cartilage implantation is just as successful in older patients as it is in younger ones. In this procedure, chondrocytes (cartilage cells) taken from normal, healthy joint tissue are used to make more chondrocytes. The new cells fill in the hole where the defect exists in the damaged cartilage.

Studies on the use of autologous chondrocyte implantation (ACI) among older adults are very limited. And there’s a basic philosophy that by age 45 or older, the patient would do better to have a total knee replacement instead of ACI. Recovery is faster with fewer problems.

Older adults who are healthy and active may not want a total knee replacement just yet. They may find that pain relief and improved joint function available after ACI makes it possible to return to their previous social and recreational activities.

And, in fact, comparing results of ACI in younger versus older patients in this study showed similar results. The success and failure rates were about the same between the two groups. Young or old, the same types of exclusions should remain in effect. These include the presence of inflammatory joint disease, metabolic or crystal disorders, ligament instability, and poor knee joint alignment. ACI is not an option in such cases or if X-rays show 50 per cent (or more) loss of joint space in the knee.

For patients with malalignment, additional reconstructive surgery was done to correct the mechanical axis to neutral. About half the group had some other procedures done at the same time. This included procedures such as osteotomies, ligament repairs, bone grafts, or realignment of the patella (kneecap). The goal was to correct alignment as close to normal as possible in order to prevent degenerative changes that can lead to arthritis.

The ACI procedure was followed by a rehab program designed to prevent overload and damage to the new graft. Exercises for increasing knee joint motion and strength were prescribed and gradually progressed in stages.

The first stage lasted up until six weeks after surgery. A continuous passive motion (CPM) machine was used for six to eight hours each day. With CPM, the leg is strapped into the device, which automatically keeps the lower leg bending and straightening over and over for hours. When not in the unit, the patient could walk putting only partial weight on the foot by touching the toe down. This helped maintain balance without putting load through the healing patch of cartilage.

Stage II consisted of active motion exercises, muscle strengthening, and increased weight-bearing over from week seven to week 12. Full weight-bearing was allowed by the end of 12 weeks. Stage III began 12 weeks (three months) after surgery. By this time, patients felt ready to run but were told to avoid all impact activities for a full year or more. Cutting sports were not allowed for at least 18 months.

Results were assessed before and after treatment using a wide range of rating scales to measure outcomes. For example, patient sense of well-being, sports participation, satisfaction, and symptoms of arthritis were all recorded and compared. The authors took this information into consideration while also looking at the size and type of lesion.

Three subgroups were formed using this type of classification. Some cartilage defects were small and composed of only one damaged spot (first subgroup). Others were large single lesions (second subgroup) or multiple areas of damage on the joint surface (third subgroup).

If more than 20 per cent (or more) of the graft area didn’t take or the patient continued to experience disabling pain, it was considered a treatment failure. Another form of failure was delamination. Delamination is the separation of the outer coating of the graft or splitting of the graft into separate layers. Everyone was followed for at least two years. Some patients were in the study for as long as 11 years.

Everyone in all three subgroups improved over time. Failure was reported in 14 per cent of the patients. Failures were more likely to occur in worker’s compensation patients than non-worker’s compensation patients.

The majority of patients (81 per cent) said they were satisfied with the results and would have the surgery again if they had it to do over again. A small number of patients required additional surgery either to replace part or all of the knee joint or to redo or revise the ACI procedure.

All-in-all, despite being older, potentially having lower metabolic cell activity and larger, more chronic cartilage defects, adults age 45 and older responded well to the ACI treatment approach. Failure rate was the same as for ACI in younger patients (as reported by other researchers).

The authors say that treatment of chronic cartilage defects in this age group doesn’t have to be an osteotomy (removal and realignment of bone) or full joint replacement. That’s good news for aging adults who are active and who don’t want to accept the activity limitations that come with joint replacement. Only a small number of patients felt their knees were worse than before surgery.

Anyone (young or old) who is thinking about having autologous chondrocyte implantation (ACI) for cartilage defects should be told about possible complications. Besides graft failure, one of the most common problems is overgrowth of the implanted cells called hypertrophy.

A second challenging problem is the formation of adhesions (fibrous scar tissue). Both of these complications requires a second surgery to correct the problem. As many as one-third of all ACI patients end up having a second arthroscopic procedure. They call this a second-look arthroscopy. The excess tissue is shaved away or removed, providing long-lasting positive results.

Surgeons in Europe have solved this problem by replacing the periosteal cover used to protect the implant with a new collagen membrane. This new patch is not yet available in the United States. In the meantime, careful patient selection (young or old) remains a key factor in the success of the ACI procedure. Age does not have to be an immediate strike against the patient. Obesity, noncompliance with the rehab program, tobacco use, and loss of joint space are major risk factors for failure. Such patients must be screened for and excluded from this type of surgery.

Knee dislocations are known to cause severe ligament damage with knee joint instability. If the blood vessels and local nerves in the area are damaged, the risk of losing the leg is much higher. The authors of this article report that such damage can occur even with a single ligament rupture in the knee. And what appears to be minor trauma (e.g., sports injury, fall from standing) can also cause serious damage to the blood vessels. Without early diagnosis and treatment, loss of limb is a definite possibility.

To prevent this from happening, surgeons and other physicians must be aware of the types of common neurovascular injuries that can occur with knee injury. An understanding of anatomy and mechanism of injury will guide the surgeon in planning the most optimal course of treatment for each patient.

The authors of this article review types of injuries (e.g., knee dislocation, vascular injury, compartment syndrome, nerve injury). They describe diagnostic tests for each one and recommended treatment. Timing of ligament repairs, new technology for treatment of arteries and veins, and classification of nerve injuries are presented and discussed in detail.

The authors suggest that whether one, two, or multiple ligaments are damaged in a knee injury, the surgeon should evaluate as if a total dislocation with neurovascular complications have occurred. In this way, difficult to detect damage will be recognized quickly with better final results.

The examiner should keep these key points in mind:

The results of this study from Taiwan showed that a magnetic knee wrap for patients with osteoarthritis is safe, effective, and low cost. Using measures of strength, pain, and function, the patients who used the magnetic wrap showed significant improvement over the control group who wore a placebo wrap.

This low-cost option for home treatment is good news for the many older adults who are limited by their knee arthritis. Getting up from a chair, walking, and going up and down stairs can be very difficult. A simple magnet wrap that can increase strength and reduce pain means better function and improved quality of life.

Since arthritis is a chronic disease and treatment with antiinflammatories can cause significant side effects, finding alternative ways to treat it is essential. Magnet therapy has been advertised for this condition, but studies are lacking to show if they are safe and effective.

Some published studies support the idea that a static electromagnetic field (SMF) can relieve pain. But there have been conflicting reports, so the data is not consistent. And in all studies, the placebo group also reported less pain when wearing a wrap without magnets.

The main focus of this study was the effect of magnetic knee wrap on quadriceps strength. In particular, isokinetic strength was measured. Isokinetic refers to strengthening the muscle throughout the range of motion. Patients included had mild-to-moderate knee osteoarthritis with chronic knee pain. The magnets used in this study were permanent and able to generate a static electromagnetic field (SMF).

Everyone wore the knee wrap daily during their waking hours for 12 weeks. If they had arthritis in both knees, the wrap was worn on the more painful knee. If both knees were equally painful, the wrap was placed on the nondominant leg. Patients were advised not to exercise or participate in strength training of any kind during the 12 weeks period of time.

The placebo wrap was the same size, shape, material, and weight as the true magnetic wrap. Usually in studies comparing magnetic vs. nonmagnetic devices, it is difficult to keep the groups from knowing who had the magnetic wrap and who didn’t. Nonmagnetic material does not stick to metal objects and magnetic material does. This is a very obvious clue as to which group the subjects are in. In this study, the patients were asked not to test which was the active magnet and which was a sham.

A special device (Biodex System 3) was used to measure isokinetic strength of the quadriceps (front of thigh) muscle. Everyone performed five maximal muscle contractions without stopping at two different speeds (velocity) of movement. The machine was set for 30 degrees of motion per second and 60 degrees/second. This was the main test for strength. Patients also filled out two questionnaires (Health Assessment Questionnaire, Western Ontario and McMaster Universities Osteoarthritis Index) geared to measure pain and function.

Strength improved in the magnetic wrap group right from the start. And strength continued to improve until it peaked at the end of the 12th week. On the other hand, the control group showed no improvement and even a mild decrease in strength. Patients in both groups were equally compliant (cooperative to wear the wrap as directed).

The authors believe this was the first scientific investigation into the effect of a magnetic knee wrap to improve quadriceps muscle strength. They concluded that there may be a role for static electromagnetic field in recovering lost strength in patients with painful knee arthritis.

In fact, they suspect the way the magnetic therapy works to improve strength isn’t by direct strengthening of the quadriceps muscle. They suggest that a static electromagnetic field may help turn the quadriceps muscle back on after being inhibited by changes in the nerve messages set up in response to pain signals.

The next step in exploring the use of static electromagnetic field for knee osteoarthritis is to conduct a similar study with patients who have more advanced (severe) arthritis. And a longer follow-up period for this study (and any future studies) would be helpful to see if the effects of turning off muscle inhibition associated with osteoarthritis are long-lasting.

It would be helpful to know if a short course of magnet therapy is all that’s needed to get the muscle action turned around. Strengthening programs would be more effective with better results than when conducted alone. And this added information might help explain why rehab to improve motor control and function has not helped improve quadriceps strength.

It’s not enough to know what kinds of physical training or treatment will improve quadriceps strength in this patient population. Which method is the fastest with the longest effects is important, too. Getting people back up on their feet with the pain relief, strength, and the endurance they need for daily activities and work is the goal.

It isn’t a common problem, but when a patient has an intra-articular extraskeletal osteochondroma, it’s important that it be recognized and treated and not mistaken for a more serious one. Extraskeletal means not in the bone, but in the soft tissue, and osteochondroma is a benign (not cancerous) tumor that contains both soft body tissue and bone.

The authors of this article first describe a patient with this type of osteochondroma. He is a 59-year-old male how has been complaining of a dull pain and decreasing range of motion in his right knee over the past three years. He claimed to be managing well, even with his job as a heavy worker, until a mass formed behind the knee, preventing him from bending it any more than 90 degrees, a right angle.

When the doctors examined the patient, they were able to feel the mass, but it was only mildly painful. In x-rays, the only thing that could be seen that was out of the ordinary was a mass of soft tissue behind the knee. The patient also had a bit of osteoarthritis. Magnetic resonance imaging (MRI) showed the mass in more detail.

The doctor decided to excise the mass, take it out. When the tumor was biopsied, studied in the lab, it was found that the mass had bone cells and tissue in it so the diagnosis of osteochondroma was made. After six weeks, the patient returned to his regular lifestyle and he remained tumor-free at the last follow up at 26 months after surgery.

The authors wrote this is not an unusual problem but that doctors need to be aware of the possibility in case they diagnose a chondroma, a non-cancerous tumor in the cartilage, or chondrosarcoma, a cancerous tumor. In the case of osteochondroma, it happens frequently that the patients don’t even know they have one until it starts to block their motion, as it did in the patient described earlier. Usually, after the mass has been removed, the patient returns to normal after the rehabilitation.

Physical therapists often treat athletes with patellofemoral pain syndrome (PFPS), a common cause of knee pain when squatting, kneeling, running, and going up and down stairs. There isn’t one individual test that can confirm the diagnosis of PFPS. And there isn’t one best way to treat the problem either.

That puts therapists in a bit of a quandary when it comes to choosing the right way to treat patients with this problem. Many studies have been done to sort out what works best. Is it taping? Taping with exercise? Exercise alone? What kind of exercise is advised?

It is believed that PFPS occurs because of altered biomechanics between the patella (knee cap) and the femur (thigh bone). The patellofemoral joint is where the kneecap moves up and down over the lower end of the femur. It makes sense that restoring normal patellofemoral biomechanics should reduce pain and improve function. But a one-size-fits-all type of treatment program has not been found.

Studies show that taping the knee to improve patellar tracking (movement up and down over the femur) can be helpful. But the proper (most effective) method of taping is still under investigation. Other studies have shown that strengthening the quadriceps muscle over the front of the thigh and/or hip muscles can alter the symptoms of PFPS. Exercising these muscles seems to improve proprioception (sense of joint position) in the leg. The result is decreased pain and improved function.

Yet another direction in treatment has been the use of manual therapy techniques for PFPS. In this approach, the therapist uses nonthrust or thrust manipulations of the hip, knee, and/or patella to relieve pain and improve movement. There is support that this method is successful.

In this study, five patients with PFPS were treated with a multimodal approach. This means more than one treatment method was used. Manual therapy, patellar taping, exercise, and orthotics (shoe inserts) were used to treat the entire lower extremity rather than just addressing the patellofemoral joint alone. This approach is referred to as a regional interdependent management of the lower quarter to manage patellofemoral pain.

The five patients all had been diagnosed with PFPS. They were between the ages of 14 and 50 years old. Everyone completed a battery of tests before and after treatment. The Numeric Pain Rating Scale and Kujala Anterior Knee Pain Scale (AKPS) were used to measure pain intensity. The Lower Extremity Functional Scale (LEFS) was used to measure level of difficulty with tasks and function. And the Global Rating of Change Scale (GRPS) was used to measure patient perception of change from beginning to end.

A physical therapist performed an in-depth exam of each subject. Posture, neurologic screening (including neurodynamic testing), and muscle flexibility were all evaluated carefully. Hip and knee motion and strength were also assessed. Each of the five patients was described along with the results of their tests.

The authors provided a table summarizing the exercises and manual therapy techniques used. Non-weight bearing exercises, weight-bearing exercises, and stretches were prescribed. Photos and description of the nonthrust and thrust manipulations used were included.

Each patient had a slightly different treatment program based on the results of the clinical tests performed. Everyone was taught how to do lumbopelvic stabilization exercises. These exercises focused on abdominal and hip muscles (transverse abdominus, hip extensors, hip abductors).

Exercises to improve proprioception in a weight-bearing activity were also included. Taping was used with anyone who had pain when stepping down on stairs. Direction of taping used was based on which type of taping applied relieved the pain when stepping down. Patients were taught how to do their own taping at home.

Two of the patients received foot orthotics to correct ankle and foot alignment. This intervention approach is based on previous studies showing how a pronated (flat) foot position can chronically overload the patellofemoral joint.

The overall treatment plan was progressed for each patient from session to session based on individual results. Patient visits ranged from eight to 14 over a six to 11-week period of time. Treatment was discontinued when the patient no longer had pain or was able to return to sports activities.

All but one patient experienced significant improvements that were still present six months later. The results of this study support what other research has shown — a multimodal approach to PFPS can be very effective. Case series such as this one carefully tracking the management and outcomes of patients treated for PFPS can help direct future treatment for this problem.

The theory behind the multimodal approach is that using more than one technique to address the entire kinetic chain (foot to spine) works because it addresses the biomechanical links between the foot, ankle, knee, hip, pelvis, and spine. The results support the idea that PFPS occurs as a result of multiple interactions (dysfunctions) between these regions.

Treating the lower extremity as a functional unit may respond no matter what combination of specific interventions are used. The authors suggest that future studies are needed to confirm or correct this approach. And more studies are needed to compare thrust versus nonthrust techniques for each area (knee, hip, pelvis, spine).

Cartilage defects in the knee joint that go clear to the bone can be treated these days. The technique developed to repair this problem is called autologous chondrocyte implantation (ACI). The procedure is done by taking normal, healthy cartilage cells from the patient. They use these cells to grow more cells in a laboratory setting and then reimplant the new batch of cells in the damaged area of the knee joint. The new cells usually adapt well to the new environment.

Although this treatment method works well, there can be problems or complications after the procedure. In this study, surgeons from Switzerland and Germany follow a group of over 300 patients who had ACI procedures. Three different ACI techniques were used. They watched to see which patients had the most problems after ACI and what those problems were.

The goal was to find the best way to treat these complications. But in the big picture, researchers hope to find ways to prevent problems from occurring after ACI that require revision (a second) surgery. The three methods used were: 1) periosteum-covered ACI, 2) Chondrogide membrane covered ACI, and 3) a three-dimensional matrix-associated ACI.

Two thirds of the patients had the Chondrogide membrane covered type of ACI. One-fourth had the three-dimensional matrix. The rest (14 per cent) had the periosteum covered ACI procedure. This may be the first large study to report on the problems that can occur with ACI. In the past, ACI failures were only discussed in single reports with a small number of cases. By combining the patients of three surgeons together over a period of five years (2001-2006), they were able to study a much larger group and report specifically on complications.

They found four major problems after ACI: 1) hypertrophy, 2) disturbed or inadequate fusion, 3) delamination, and 4) graft failure. Hypertrophy refers to overgrowth of the transplanted tissue. Insufficient fusion describes patients in whom the transplant just didn’t regenerate like it should. The edges between the healthy, normal tissue and the implanted cells didn’t meld together to form a solid, smooth surface. Delamination is the separation of the cartilage layer from the bone underneath. Shearing forces can cause these two layers to slide apart before fusion takes place.

In a few cases, there was osteonecrosis (death of the bone underneath the cartilage transplant). In all cases, patients were diagnosed on the basis of pain and/or loss of function after the surgery. Symptoms occurred anywhere from the first six months up to three years later. Sometimes MRI scans showed abnormal cartilage or subchondral bone signals. Subchondral refers to the first layer of bone under the cartilage. But surgeons could not rely on the MRIs as the final diagnostic tool. Only after performing arthroscopic revision surgery could they make the diagnosis with certainty.

Of the 349 ACI procedures that were done, 52 required revision surgery due to symptomatic complications as described. Information collected and analyzed included the different types of surgical techniques mentioned, location and size of the defects, and age of the patient.

Most of the defects requiring revision surgery were on the medial (inside edge) of the femoral condyle or on the back of the patella (kneecap). The femoral condyles are two round knobs found on the end of the femur (thigh bone). The condyles rest on the top surface of the tibia (lower leg bone) to form the knee joint.

But the location of the defect did not test out to be a significant factor overall. The type of ACI technique was more important. Patients who had the periosteum-covered ACI had the highest rate of complications. Hypertrophy of the graft was the most common problem in all types of grafts, but especially among patients with the periosteum-covered graft.

Patients with Chondrogide-covered ACI and matrix-associated ACI were more likely to end up with a disturbed fusion site, but the risk of this happening was fairly low. Hypertrophy and malfusion were observed most often in patellar defects.

Age and size of defect did not have any influence on the final outcomes of the surgery. There were some trends noticed by age (hypertrophy in younger patients; insufficient regeneration in older patients). Understanding the significance of this finding may take some time.

Having observed the clinical results of these four types of ACI, the next step is to understand the nature of the repair process and why it works better with some (but not all) graft types. After that, surgeons will look for ways to modify current treatment techniques for improved outcomes.

Right now, the treatment approach in revision surgery is to remove the damaged, dead, or insufficient tissue and regraft the defect. This usually results in a good return of function, but there are no studies yet on the clinical outcomes of revision surgery for failed ACI.

The authors conclude that their study was a good start on clarifying the results of ACI. The observations and summary they made about complications after the primary (first) procedure were the first published. Having a large enough group of patients to be statistically significant was a key benefit of this study.

Older adults with knee pain can lose independence and function quickly. Joint and mobility problems lead to inactivity and weight gain. Obese older adults are especially at risk for knee pain resulting in disability. And whereas we once thought that disability in older adults was irreversible, studies now show that recovery is possible.

In this study, an effort is made to better understand the progressive transition to disability. By identifying risks for and stages of disability, it may be possible to prevent, shorten, or reverse the process.

Researchers used a model called the Hidden Markov Model (HMM) to show the various changes that occur in activities of daily living that can lead to disability. This model provides a statistical method for analyzing the data collected.

Data was collected using a special tool to assess disability called the Pepper Assessment Tool for Disability. The Pepper Assessment Tool has been tested and found to be reliable and valid. The authors note that they have used this particular self-report survey for over 15 years with the aging adults at their center.

The Pepper Assessment Tool was used with almost 500 men and women 65 and older. Each participant had chronic knee pain that was present almost every day. The pain limited their movement and/or activities. Everyone in the study completed the tool at the start and again 15 months and 30 months later.

The Pepper Assessment Tool looks at three key areas of function and participation in older adults. These include activities of daily living (ADLs), mobility, and Instrumental Activities of Daily Living (IADLs). ADLs measure self-care activities (e.g., bathing, getting out of bed, brushing teeth, eating). Mobility refers to the ability to walk and climb stairs. IADLs describe more complex tasks such as socializing with friends and family, managing money, or preparing meals and keeping the house clean.

The Hidden Markov Model helps the researchers analyze the participants’ answers to questions on the Pepper Assessment Tool. Patterns emerge over time that help define states of disability on a continuum (from mild to severe). This concept places disability as a state of being with phases and transitions between phases rather than as a trait used to describe someone.

Using the Hidden Markov Model, the researchers found six separate states of disability (from the least or no disability to severe disability). A distinct pattern or disability profile emerged from the data analysis. The first phase of disability is a decline in mobility such as managing stairs or lifting heavy objects. Loss of activities of daily living (ADLs) occurs next. The last phase is a loss of instrumental (social, financial) activities.

Changes occur over time with a transition phase between states of disability. Adults with greater disability are less likely to recover. Adults in the first three disability states have the best chance of returning to a lower state of disability (and a higher state of function). More obese adults have less of a chance of remaining healthy. Once the obese individual is in a severe state of disability, they are more likely to remain at that level of disability.

This study showed that disability is a dynamic (changing) process. Obesity is a major risk factor in the disablement process. Using the Pepper Assessment Tool and the Hidden Markov Model, the multistate nature of disability became apparent. Using patients with knee pain and observing the process of disability developing and changing over an almost three year period made it clear that there is a pattern of emerging disability.

The most demanding tasks tend to go first. Changing body position (getting in and out of bed, chair, or car) is the first mobility function to be compromised. Physical tasks (cooking, cleaning, self-care) become limited much faster than cognitive function (paying bills, making phone calls).

What is the practical application of this information? First, knee pain is common in older adults and may be a key feature in loss of function. Second, lower-limb strengthening is important in preventing and/or recovering from loss of mobility. Without intervention, decline is much faster than recovery. And once a person starts to transition toward disability, the probability of returning to a previous state of function is less. Obesity stacks the odds against recovery.

The Pepper Assessment Tool is a helpful way to measure a patient’s level of disability. It allows the health care provider with a means to track changes over time. A change in function or loss of activities highlighted by this tool can trigger a referral to physical therapy sooner than later. Preventing or regaining loss of function in aging adults is important in avoiding the decline into institutional care (e.g., nursing home or other extended care facility).

Bone graft material is used whenever there’s a need for extra bone to support a fracture site or defect in the bone. It’s easily available (taken from the patient’s pelvic bone) and inexpensive. And it is bone inductive (fosters bone growth) to provide structural support to the damaged area.

The downside is that the graft site can be painful for a very long time. In some cases, infection can delay recovery. Patients often report difficulty walking due to the pain. And the combination of pain and impaired walking result in loss of function.

To help patients avoid the major and minor complications of bone graft, scientists are exploring the use of bone substitutes. One of those bone substitutes (alpha-BSM) is the subject of this study. Patients with an acute fracture of the tibial plateau were the subject of this multicenter study. Twelve study sites from around the North American continent were involved.

The tibial plateau is the flat top of the upper portion of the tibia (lower leg bone). This type of fracture was once called a bumper or fender fracture. During a car accident (fender bender), force directed from the femur (thigh bone) down onto the tibial plateau, results in fracture of the plateau. Car accidents aren’t the only way this type of injury occurs. Falls, industrial accidents, and getting hit by a car as a pedestrian are also possible ways to sustain a tibial plateau fracture.

Patients were randomly assigned by computer to one of two groups. The first group had an autogenous iliac bone graft. Autogenous means the patient’s own bone was used. The second group received alpha-BSM, a bioabsorbable substitute.

FDA regulations required a 2:1 ratio of bone substitute to bone graft patients. This means that twice as many patients had the bone substitute compared to the bone graft group. The reason for this was because bone graft is considered more risky with a greater chance of complications.

Alpha-BSM is a calcium phosphate powder that can be reconstituted with saline (salt solution) and implanted into the bone defect. Heat is created within the material and within four hours, it is set and strong enough to resist compression. Once the fracture was repaired, the remaining hole in the bone was filled with bone graft or bone substitute.

All patients were followed at regular intervals for 12 months. Outcome measures (results) included X-rays and knee range-of-motion. X-rays were used to see if the bone had healed properly and to look for subsidence. Subsidence refers to a collapse or sinking of the articular cartilage and the first, thin layer of bone down into the bone matrix. The independent panel of orthopedic surgeons who reviewed the X-rays also looked for signs of early resorption of the graft.

They found a higher rate of subsidence in the bone graft group. In other words, collapse and resorption of the bone was more likely in the bone graft group. As many as 30 per cent of the patients in the bone graft group were affected. This was compared to only nine per cent in the bone substitute group. Most of the time, subsidence occurred early on (during the first three to six months after surgery).

In summary, alpha-BSM bone substitute is an acceptable replacement for bone graft material. In fact, it appears to be a better choice. X-rays taken a year after the fracture show the alpha-BSM material is still present in most fractures. It is stiffer, offers more support, and holds up better under load compared with autogenous bone graft. There is also less sideways shifting or subsidence of the healing bone with this type of bone substitute.

Degenerative joint disease (also known as osteoarthritis or OA) is a common problem in the aging adult. Two out of 10 people over the age of 60 develop OA. Knee arthritis is especially common. Pain and loss of motion from this condition can really limit activities and lead to increasing disability.

At the same time, surgeons are able to replace the knee joint with a perfectly functioning implant called a total knee replacement (TKR). In fact, TKRs have become so successful their number has increased over 80 per cent in the past 10 years.

Scientists collecting data on TKR patients have noticed a very important trend. Once the first knee joint is replaced, it seems there is a predictable pattern of deterioration in the opposite (nonoperated) knee. It’s not uncommon for patients with one TKR to end up having a second joint replacement on the other leg.

Is this a coincidence or is there a reason for this pattern? A recent study from a Biomechanics and Sports Medicine Laboratory at the University of Tennessee was able to shed some light on this. They looked at the angle of the knee in the operated and nonoperated knees of 18 patients and compared it to with an equal number of knees in healthy adults (the control group).

A seven-camera system designed to capture motion from all angles was used to evaluate the operative group and the control group. A force plate was used to measure ground reaction forces (force up from the ground through the leg to the knee). Walking speed was also recorded. Everyone wore the same shoe while walking to reduce the effect of footwear on the results.

They found an increase in the first peak knee adduction moment of the nonoperated leg (compared to healthy controls and even compared to the operated leg). The adduction moment is the angle formed by the femur (upper leg or thigh) as it connects at the knee with the tibia (lower leg). The measurement is taken in the frontal plane. That means from the front of the patient rather than from the side or from the back. The first peak moment occurs as the person steps onto the foot (stance phase).

The increase in angle suggests there may be some change in the biomechanics of the knee and leg during the stance phase of walking when the patient puts weight on the leg. It’s also possible that the patient has a new knee but still walks with the abnormal gait pattern that was present before surgery. This effect could speed up deterioration of the other knee leading to osteoarthritis and the need for a second knee replacement.

Since researchers have just started looking for reasons why, we don’t know if changes present before the first knee replacement are a factor or if knee angles, uneven loads placed on the knees, walking speed, or some other factors are the cause. And it’s not clear yet if surgeons can predict who will develop problems on the opposite side based on these findings. More studies are needed to sort out all the effects and factors.

In the meantime, the authors suggest the results of this study indicate a need to rehab both knees after a total knee replacement is done. The operated knee is important but the effect of the nonoperated limb can’t be ignored.

There is some convincing evidence that altered kinematics is a major factor in patellofemoral pain syndrome (PFPS). Kinematics refers to patterns of movement — specifically how the patellofemoral joint and the knee joint rotate and glide in relation to one another during motion.

The patellofemoral joint occurs where the patella (kneecap) glides up and down over the femur (thighbone). Increased pressure from contact between the patella and the femur can lead to PFPS. This is called retropatellar stress — it means behind the kneecap.

Stress on the patellofemoral joint is made worse by rotations of the lower leg during weight-bearing activities. And repetitive actions with weight-bearing load during running and jumping increase retropatellar stress. The result is PFPS.

In this study, physical therapists attempt to use a two-dimensional (2-D) method of measuring knee alignment. The measurement was called the frontal plane projection angle (FPPA). The hope was to find a simple tool to use in the clinic to measure altered kinematics during weight-bearing activities.

The two planes of kinematics (motion) investigated were frontal and transverse. Frontal refers to a line down the middle of the joint dividing it into the front half and the back half. Transverse is the plane through the knee from side to side.

Physical therapists often work with athletes with PFPS. If they could identify who has altered movement patterns, it might be possible to treat the problem and prevent PFPS from developing. To test their theory, they compared two groups of similar females. One (control) group was made up of healthy, active women between the ages of 18 and 35. They did not have any knee pain or knee problems. The second group were also active in recreational sports requiring running and jumping. But women in the second group had PFPS.

A 2-D method was used to measure the frontal plane projection angle. Other studies have used 2-D measurements of knee angles and kinematics. When compared with 3-D high-speed motion analysis, the results were promising that 2-D would be accurate enough to use in the clinic. Three-dimensional motion analysis is expensive and not usually available in the clinic. If it was successful, the 2-D device could measure leg alignment during weight-bearing activities.

The equipment used was simple, portable, and inexpensive. Everyone wore the same type of shoe (Nike Air Pegasus). The test required only a single-leg squat, which uses less space than testing athletes during full-speed cutting movements. A digital photograph of the leg was taken as the subject bent the knee for the single-leg squat position. The frontal plane projection angle (FPPA) was taken from the image.

At the same time, transverse and frontal plane kinematics of the hip and knee were recorded using a high-tech 3-D (computerized) movement analysis system. The researchers compared the 2-D measurements for FPPA during single-leg squats with 3-D analysis of hip and knee movement for the same squat motion. The 3-D system was also used to record ground reaction forces during running and single-leg jumps. Results were compared for women with PFPS and whose who didn’t have PFPS.

The therapists also measured other factors that might be important later when identifying women at risk for PFPS. For example, each woman was asked to rate her pain during squatting, long periods of sitting, running, going up or down stairs, and jumping. This was reported as a number on a scale from zero (no pain) to 10 (worst pain).

Other factors were also evaluated to see if any of these would be able to predict who would develop PFPS. These included: unknown cause for symptoms, pain behind the knee with pressure over the patella, and change in function. Here’s what they found:

Tearing or rupturing the anterior cruciate ligament (ACL) is a common knee injury, especially in people who participate in certain sports. And, as more people become active, surgeons are performing more ACL rupture repairs than ever before. Surgeons usually repair the ACL using a graft to hold the ligament together. Unfortunately, the graft doesn’t always hold and the repair fails. This means the patient needs revision surgery for another attempt at repairing the injury. Up to now, doctors haven’t agreed on what they classify as a failure after ACL surgery, but there are four main categories of failure: arthritis and pain, loss of motion, inability to stretch the knee out, and the knee becoming loose (lax) again.

It’s difficult to determine what exactly the failure rate is of ACL surgery, although the numbers 10 percent to 20 percent have been mentioned. However, many failures aren’t reported, so this may really affect the true number. The authors of this article wanted to study the clinical and stability results between initial ACL surgery and revision ACL surgery, and to compare revision surgery and the different types of graft materials used by the surgeons.

Researchers recruited 55 patients, who had 56 surgeries total who were between 21 and 55 years old at the time of surgery. Other surgeons had done 52 of the surgeries in which the grafts came from various sources, from both the patient and from donors. The types of grafts chosen (Achilles tendon, knee area, patient or donor) depended on the patient’s situation, which included their age, activity level, economic status, if there were any earlier surgeries, and the surgeons’ preference.

To assess the patients and their knee function, the researchers used the Lysholm score and International Knee Documentation Committee (IKDC) measurement criteria. To assess if the patients’ knee was stable, a arthrometer was used. Other tests and x-rays were also used to get a better impression of what was going on with the knee. As a result of the assessments, the patients were placed in to one of two groups: mild (grades 0 and 1) and severe (grades 2, 3, and 4).

All patients were operated on while they were under general anesthetic. Immediately after surgery, some patients were permitted to begin exercising their quadriceps, the muscle at the front of the thigh. By day three after surgery, they were allowed to do partial weight bearing. A brace was applied to the knee on day four after surgery and range of motion exercises were increased by 15 degrees every week. After four weeks, the patients were encouraged to 90 degrees bending of the knee, by six weeks it was 135 degrees, and by six months, they were allowed to straighten their knee completely.

After looking at the data, the researchers found that according to the results of the Lysholm score, which is on a scale of one to 100, was on average 72.6 before surgery and improved to 93.7 after surgery. When looking at results of the IKDC, the results showed that 64.1 percent of the knees were normal after surgery, 30.8 percent were near normal, only 5.1 percent were abnormal, and none were severely abnormal. When looking at revision surgery, done if the first one failed, the Lysholm score changed from 63.3 before surgery to 84.6 after. As for normalcy, after revision surgery, it was found that only 23.2 percent were classified as normal, 62.5 percent were nearly normal, 10.7 percent were abnormal, and 3.6 percent were severely abnormal. The researchers were also interested in how stable the knees were after surgery, compared with before the repair. They found that there was a significant improvement in the stability of side-to-side motion after the first surgery, but it wasn’t as good following revision surgery.

Failures of knee repairs were most often due to technical errors during surgery. For example, the knee wasn’t always positioned ideally, not allowing proper healing.

The authors wrote that there are many factors that are involved in ACL surgery failures, but they aren’t as clear in revision surgery failures. The researchers looked at the technical aspects and the materials used for grafting, but there weren’t many differences found with the graft successes or failures among revision surgeries. The authors then concluded that if revision of ACL repair is needed, it could provide stability and improvement in knee movement, but revision surgery was usually not as successful as initial repair surgery.

Is there a reason why patients stop kneeling after a partial knee replacement (PKR)? If there is, doctors and physical therapists haven’t been able to find it. And without the ability to kneel, daily activities can become quite restricted.

In this study, physical therapists describe how to regain this skill. According to preoperative tests, many patients were unable to kneel before knee surgery. Even more had to give it up after surgery. The patients gave many different reasons for the inability to kneel. These included placement of the scar, loss of knee (or other joint) motion, pain, and skin numbness.

The therapists decided to try a six weeks postoperative intervention to improve or restore kneeling after PKR. They included education, advice, reassurance, and specific instructions on kneeling.

All patients were seen one time for a follow-up intervention visit approximately six weeks after the PKR operation. Everyone had the Oxford® Partial Knee Replacement from Biomet Orthopedics. This partial knee implant was first approved for use in the United States by the Food and Drug Administration in 2004. Since then, it has become increasingly more popular.

It is designed to repair only the medial side of the knee (side closest to the other knee). About one in four patients with osteoarthritis have limited knee arthritis, known as medial compartment arthritis. A partial knee replacement replaces only one side of the knee joint. A total knee replacement removes all the knee joint surfaces.

Some advantages of the Oxford® partial knee replacement are that it removes much less bone and cartilage than a total knee replacement. The implant is much smaller than a total knee implant. And the knee is less painful afterwards making recovery much faster.

By keeping all of the undamaged parts, the joint may bend and function more naturally compared to a total knee replacement. In theory, kneeling should be possible when it might not be allowed with other types of implants.

Patients were randomly divided into two groups: those who received kneeling education and instruction (group 1) and those who received the routine follow-up instructions (the control group).

Before surgery, everyone completed the Oxford Knee Score (OKS) and had a digital photograph of the knee taken. The Oxford Knee Score is a self-report survey that specifically asks about kneeling. There was no difference in ability to kneel between the two groups before surgery. The photograph provided a record of scar position and numbness (drawn in with markers). Range-of-motion for the knee was recorded to the nearest degree.

Patients in the kneeling group were told they could kneel on the implant without causing it any harm. The therapist showed them how to kneel on a soft mat using arm support to aid in getting up and down. Kneeling was done on both knees. The therapist offered feedback on proper posture and alignment and answered any questions the patients had. Limited knee flexion prevented sitting back fully on the heels.

At the one-year follow-up visit, one physical therapist re-evaluated everyone in both groups. The therapist did not know who was in the intervention group or who was in the control group.

Both groups improved in their ability to kneel. The control group that received routine care probably made progress in kneeling because of improved function and relief of pain after surgery. However, the results did show a much greater improvement in kneeling for the intervention group compared to the control group.

This was the first study published on training patients to kneel after a partial knee replacement. Kneeling is important to maintain activity level and overall function. Without the ability to get up and down (or into and out of a kneeling position), older adults have no way to get up off the floor after a fall. Household chores can be more difficult when kneeling is no longer possible. And patients who can’t kneel during religious services may choose not to attend, thus limiting their social life and reducing their quality of life.

The authors conclude that education and supervised intervention after a partial knee replacement can make a difference. Practice kneeling (getting down and getting up) under the guidance of a physical therapist was very helpful in restoring this valuable skill.

There was no link between scar position, numbness, and range of motion and a change in kneeling ability. Sensitivity of the knee near the kneeling area from nerve injury was unpleasant but didn’t affect kneeling ability. It appears that the key factors were to reduce fear and provide direction on how to kneel safely and easily.

Although knee flexion is needed to start kneeling, patient range-of-motion was not significantly different before and after surgery. This finding suggests that a loss of motion is not the reason patients can’t or don’t kneel after partial knee replacement. And problems in other joints were not a barrier to kneeling. Patient with arthritis in other joints reported being able to kneel using the therapist’s suggestions.

Given the results of this study, the authors remind us that only patients with an Oxford PKR were included. The good results need to be tested and reproduced in patients with other types of implants. Further studies may find more than one possible pattern of kneeling that could be integrated into the rehab program.

Physical Therapists faced with patients who have knee pain must make sure the problem is really coming from the knee. This is true for all musculoskeletal problems, whether it’s back, neck, shoulder, hip, knee pain, and so on.

To accomplish this, the physical therapist performs a regional exam. Joints above and below the area of pain or other symptoms must be considered as a potential source of the problem. This concept is referred to as the regional interdependence model of patient examination.

In this study, the case of a 25-year-old female runner with knee pain was presented. It turned out that her symptoms were really caused by a problem in the sacroiliac joint (SIJ). How did the regional interdependence model help guide the diagnostic process?

The exam begins with a thorough history. Although the patient was involved in training for a marathon, she could not remember any injury or think of any cause for the hip pain. The pain was severe enough for her to stop running. The patient was screened carefully for risk factors and possible etiology (cause). Questions were asked about training, injuries, medications, menstrual cycle, and past medical history. Everything was negative as a possible cause of her knee pain. ‘

The exam continued with an evaluation of posture, range-of-motion, muscle strength, and joint stability. Special tests were performed to help identify impairment of the soft tissues around the knee. There were no signs of a knee joint problem.

Knee pain can be caused by disc problems, or hip, SIJ or ankle joint problems. The therapist performed a regional interdependent exam involving both legs. Muscle flexibility, alignment, and exam of the joints above and below the knee were carried out.

The lack of any positive findings caused the examiner to broaden the regional exam to include the sacrum and SIJ. The author reports on selected reliable and valid tests that were performed and their results.

The physical therapist’s diagnosis for this patient was referred knee pain secondary to sacroiliac joint dysfunction. A second, more descriptive label was suggested. From an osteopathic biomechanical model, this problem would be labeled as a right-sided pubic elevation and backward rotation of the ilium with a rotated sacrum.

The problem was likely caused by a new lunge exercise the patient started the day before her symptoms began. The deep squat position may have contributed to a shift in SIJ alignment. Tight hamstring muscles and the repetitive force from the ground up through the joint from running were likely aggravating factors.

The diagnosis was confirmed when symptoms were relieved after one treatment. Physical therapy treatment included isometric contractions and a manipulative procedure to reposition the SIJ. A home program of flexibility exercises and instructions to avoid deep lung stretches was advised. The patient resumed her running and training schedule without any problems. She completed her marathon successfully.

The author makes note of all the possible problems with this working diagnosis. For example, we know there’s a link between the knee and the SIJ. But the value of some of the tests related to the SIJ and pelvis has not been proven yet. Other factors such as patient expectations, the placebo effect, and neurological mechanisms may have a significant role.

The value of this case report was to point out the importance of a regional interdependent exam for patients with musculoskeletal problems. Although the exact mechanism for referred pain is not always known, a broad exam of this type will help physical therapists identify the structures involved. A careful diagnosis will direct treatment to be as specific as possible. A goal is to get patients like this one back on their feet and running!

When health care professionals such as physical therapists see a large number of patients with the same problem, they look for evidence to support the best way to treat that condition. That’s the case with patellofemoral pain syndrome (PFPS), a common problem for many athletes and active young adults.

PFPS causes pain around and under the patella (kneecap). Activities that increase the load on this joint aggravate the condition. For example, many patients with PFPS report that walking, running, and using stairs make their symptoms worse. Moving the knee after a long period of sitting can also cause pain.

Clear treatment guidelines based on evidence create best practice to optimize patient outcomes. These guidelines are often developed as a result of summaries from systematic reviews. In a systematic review, researchers search for all studies on a specific topic. Studies that meet the criteria for high quality methods in research are included. Treatment protocols backed by sufficient evidence are reported.

But systematic reviews must be done in such a way that they are critical and valid. Good rating scales using multiple assessors are available to assist researchers with this process. In this study, a previously validated tool called the Quality Assessment Scale for Systematic Reviews was used to look at systematic reviews already published on nonpharmacological (nondrug) treatment for PFPS.

Nonpharmacologic treatment included exercise therapy, manual therapy, and ultrasound or other physical agents. All treatments were done by a physical therapist. The use of taping and orthotics (supportive shoe inserts) was also included. Only published systematic reviews and reviews in English were selected. They were published between the years 2000 and 2007. Only those with an unbiased (acceptable) way of searching for articles were allowed.

Appropriate items for the new quality assessment scale were selected from various checklists, texts, and discussions with experts. Several teams of reviewers applied the scale to the systematic reviews on PFPS. The scale was tested and refined until it met all the criteria needed to be valid and reliable. Cutoff scores were identified to determine which reviews were high quality.

Once the reviews were analyzed and selected, then the findings were summarized for the high quality systematic reviews. In the end. three systematic reviews passed the test. They were all Cochrane Reviews, an organization known for its quality systematic reviews.

Treatment interventions studied included exercise therapy, ultrasound, and orthotics (for the foot and knee). There were no acceptable studies on the use of patellar taping (a popular treatment method). The conclusions of these reviews were as follows:

Studies show that athletes who tear their anterior cruciate ligament (ACL) often damage other soft tissues at the same time. Meniscus and cartilage tears are the most common injuries associated with ACL rupture. Meniscal tears and meniscectomy (removing a torn meniscus) are both risk factors for developing osteoarthritis of the knee.

The usual treatment for ACL tears is reconstructive surgery. The goals of ACL repair are to stabilize the knee and prevent further damage to the meniscus. But do patients really need this surgery? From many other studies, we know that having ACL surgery doesn’t prevent arthritis from developing. What happens to patients with ACL and meniscal tears who don’t have surgery? What’s the risk of arthritis for these patients?

In this Swedish study, 100 patients with complete ACL tears were treated with early neuromuscular rehab and activity modification. Patients were supervised by physical therapists in hour-long sessions twice a week for five to eight months. A program of neuromuscular rehab was provided. Patients were advised to avoid contact sports (e.g., soccer, handball).

Everyone was followed at regular intervals for 15 years. Knee function, symptoms, and amount of arthritis were measured. Weight-bearing X-rays were used to measure the arthritis. The Knee Injury and Osteoarthritis Outcome Score (KOOS) was used to measure symptoms and function. It was noted that no one had any signs of arthritis at the time of diagnosis. X-rays and arthroscopic exam were used to make the initial diagnosis.

Some of the patients (23 per cent) in this study ended up having ACL repairs. Approximately one-third of the 100 patients (35 total) had a meniscectomy. Half of the meniscectomy group developed knee arthritis. No one in the other half (no meniscectomy) had arthritis even after 15 years.

A large number of patients (68 per cent) in the nonoperative group received no further treatment after the physical therapy program. They remained pain free. The combination of intact menisci and nonreconstructed knees seemed to have the best results.

Much of today’s research efforts are geared toward finding the subgroups of patients who would benefit the most by a particular treatment approach. Finding a subgroup of patients with ACL tears who need surgery could help reduce the risk of developing osteoarthritis. Likewise, finding the subgroup who don’t need surgery but could do well with nonoperative rehab could increase quality of life and patient satisfaction while reducing total health care costs.

Based on the results of this study, the authors conclude that changing activity level for patients with ACL injury is an acceptable treatment approach. The initial treatment does not have to be with ACL repair to prevent arthritis. It is possible to follow a program of sports activity modification including avoiding contact sports.

Monitoring patients for signs of meniscal problems and treating them when necessary is an acceptable treatment approach. Saving the meniscus seems to be an important way to prevent knee osteoarthritis after ACL injury.

Studies show that athletes involved in noncontact jumping sports have the highest rate of anterior cruciate ligament (ACL) injuries. The main mechanism of injury is called plant-and-cut maneuvers. There is too much load on the knee with the foot planted on the ground while the player changes direction quickly.

Since athletes in jumping sports seem to be at greatest risk for ACL injury, these researchers studied highly trained ballet and modern dancers. They suspected that with all the jumping and balance training involved in dance training, dancers might have a lower incidence of ACL injuries.

It turns out that elite dancers had far fewer ACL injuries compared to athletes involved in jumping activities. And, in particular, ballet dancers had a much lower risk of ACL injury compared to modern dancers. Female modern dancers were 13 times more likely to injure themselves compared to male modern dancers.

Why the differences? That’s what this study explains. It seems that ballet dancers perform more than 200 jumps in a daily 90-minute technique class. The rigorous training is enough to prevent ACL injuries. This is true even though load on the knee during jump landings in dance can put up to 12 times the dancer’s body weight in force on the knee joint.

They found this out by studying almost 300 dancers from four New York City area dance groups. Modern and ballet dancers between the ages of 18 and 41 were included. All dancers were followed for five years. Comparisons were made between athletes and dancers and between ballet and modern dancers. Measures taken for comparison included body mass index (BMI), Q-angle of the knee, muscle strength, and joint range-of-motion (hip and knee).

All new injuries were reported to the physical therapist or athletic trainer assigned to the dancer. All factors related to the injury were carefully collected and recorded. Time of day, season, and type of shoe or floor surface were reported. Dancer’s mood (and for women, menstrual status) at the time of the injury was noted.

Time in training or performance was also reported throughout the five-year period. This was referred to as dance exposure. In the end, there were 12 ACL injuries among 298 dancers. Most (92 per cent) occurred when landing from a jump onto one leg.

Looking at all the variables, there was no evidence that race, gender, use of oral contraceptives (birth control pills) were linked with the injuries. Joint motion and strength differences were not able to explain differences between dancers with ACL injuries and noninjured dancers.

Most of the injuries occurred during a performance at the end of the season or late in the day after a long rehearsal. This finding suggests fatigue as a factor affecting neuromuscular control. The overall ACL injury rate for dancers was between 0.2 and 0.4 per cent. This is much lower than the range among other jumping athletes reported as being between one and eight per cent.

The authors offer several theories for the low rate of ACL injuries among dancers. First, dance training focuses on balance, alignment, footwork, and control. All of these skills may improve balance to a precise level needed to land single-leg jumps without injury. Second, dancers practice hundreds of jumps every day.

Third, jump practice progresses over time with supervision and guidance of an experienced dance instructor. And finally, unlike athletes, dancers practice the same steps in a routine. There are no surprise or unexpected movements to respond to. Rarely is contact with another dancer the cause of an ACL injury.

The higher rate of ACL injury among female modern dancers may be related to differences in postural and specific movements more typical among modern dancers. Modern dancers are more likely to make sudden changes in movement, speed, and direction. They are also involved in lifting other dancers, which is something ballerinas don’t do. The direction and angle of jumps is also different for modern dancers.

In summary, the low incidence of ACL injuries among dancers points to different training techniques between dancers and other athletes. A focus on alignment, posture, and balance may help reduce injuries in athletes involved in jumping activities. For dancers, monitoring fatigue and focusing more attention on reducing fatigue may be of benefit.

The treatment of meniscus injuries has progressed and changed over the years. Meniscectomy (removing the meniscus) was the first procedure used. But long-term studies showed degeneration of the joint cartilage as a result. Meniscal repair is now performed whenever possible.

Repair procedures have also evolved over time. Meniscal autologous transplantation (MAT), osteochondral allograft(OA), andautologous chondrocyte implantation (ACI) are three of the newer repair methods. MAT repairs the meniscus. OA and ACI are used to repair damage that goes deeper into the cartilage layer underneath the meniscus.

To prevent complications, only one operation has been done at a time. In this study, patients had both the MAT and either the OA or the ACI at he same time. Follow-up for two years has shown good early results. Thirty (30) patients who had a meniscectomy with persistent painful symptoms were included. Symptoms were reported as knee swelling with activity, crepitus, and pain along the joint line. Crepitus is the snapping or crackling felt or heard in the joint.

Transplantation and cartilage restoration were done by one surgeon. The patients were divided into two groups: MAT with OA (group 1) and MAT with ACI (group 2). The authors describe the specific techniques used for each operation. In some studies, patients are randomly placed in one group or the other. In this study, the choice of treatment was made by the surgeon on an individual basis. Important factors were age and details of the lesion (size, location, depth).

There are also guidelines published to help surgeons make the best treatment decision. For example, younger patients with small defects can have the fresh-frozen ACI. Older patients with more bone loss and deeper defects are given fresh OA grafts.

After surgery, everyone followed the same six-to-12 week rehab program. Full motion and return to full activities was expected by the end of 12 months. Results were measured and reported in terms of symptoms, function, and level of sports activity. Joint range-of-motion and ligament stability were evaluated. Anyone who had to have revision surgery of the cartilage repair was considered a failure. Patient satisfaction was also used as a measure of success.

At the end of two years, 90 percent of the patients were satisfied with the results. Nearly half of the two groups had normal motion and function. X-rays showed good integration of the grafts. Most of the defects had filled in nicely with smooth edges. Complications after surgery included mild overgrowth of the ACI patch, softening of the graft, and one graft failure.

There were some differences between the two groups. The OA group all had repair of the medial compartment (side closest to the other knee). The ACI group had an equal number of repairs to the medial and lateral sides of the joint. Lateral refers to the outside half of the joint (away from the other knee). There were age and defect size differences between the two groups. As recommended, patients who had the ACI were younger and had better function before the surgery compared to the OA group.

The authors concluded that combining transplantation of meniscus and repair of the cartilage underneath can be done at the same time with a good result early on. This is good news for young, active adults with cartilage damage after meniscectomy that is causing pain and limiting function. Up until now, standard practice was to withhold the MAT from patients with defects of the cartilage because of the complications.

With continued study and improvements in surgical technique, surgeons expect to be able to use these procedures combined together with more and more patients. There will be fewer patients who can’t have the procedures for various reasons. Long-term results of the combined implant procedures are unknown at this time. Future studies over five- and 10-year periods of time will help shape future treatment guidelines.

Fractures, or breaks, of the tibia (shin bone) are the most common type of break in the longer bones of the human body. These fractures can be clean breaks with little or no bone movement or they can be severe breaks that also cause damage to the muscles, blood vessels, nerves, and body tissues around the broken bone.

When the tibia is broken in the bottom third of the bone (closest to the foot), after healing, there is a higher chance of the bones not lining up properly. In fact, this happens in about 84 percent of cases. The most common of these is when the farthest part of the bone moves away from the midline of the body. Unfortunately, this can be difficult to treat.

To fix this type of fracture, one type of repair the surgeons use is a special type of nail to join the broken bone parts. Part of the bone can be quite wide, however, making it difficult for the nail to be stabilized in the bone. This leads to the bones not lining up properly again. As well, because the lower leg moves every time the knee is bent (flexed) and straightened because of the tendons pulling on the bone, this also makes it harder for the bones to stay in the aligned, or straight, position.

When surgeons choose the type of nail to be used, they must take into account the shape of the nail, where and how the nail is curved, and so on. Proper choice will reduce the chances of the bone not being properly aligned.

The surgery itself will also play a role in unsuccessful bone alignment. The starting point of where to place the nail is critical and surgeons should start it as far as possible away from the break and work towards the break. If necessary, the surgeon can use fluoroscopy (x-ray with dye) to use as a guide for surgery placement.

Other techniques to improve how the bones align during healing include how the knee is positioned during surgery. In some cases, surgeons flex the knee, which reduces the amount of tension on the tendons surrounding the fractured part of the bone. However, the knee should not be bent more than 10 to 15 degrees, they suggest. There is one disadvantage to this approach though. In order to proceed, the surgeons must do an arthrotomy, make an incision in the knee joint itself.

Other surgeons use a plate to line up the bones. The pates are locked into place with screws. The surgeons do point out that using screws adds to the cost, but it also provides a stronger fix. The plate can be removed at a later date if desired.

A third choice is the use of blocking screws. These screws are used with nails but the screws block the nails from going outside of where the surgeon wants them to be. According to research done by Krettech et al, this approach increases the strength of the healed fracture by as much as 25 percent.

Finally, another option is external fixation. With external fixation, a support of clips, pins, and clamps hold together the fractured bone from outside the body, with parts of the hardware going through the skin to stabilize the bone. This procedure should be saved for situations where there is too much damage in the tissue around the fractures that would make interior fixation too difficult.

One of the risks of surgery is the risk of developing an infection. This can be difficult and tibial fractures seem to be particularly difficult to treat. In order to decrease the rate of infections, surgeons must be meticulous about debriding or removing dead or tissue that will die from around the fracture.

Infections can occur at any time after the fracture, from the acute period (up to four weeks after the fracture) to several months or even years later. Physicians have noted that certain types of injuries have more infections than others. This includes crushing types of fractures and open fractures (where the skin has been broken). As well, if there has been an open fracture, if it was exposed to dirt or contamination of any sort, the risk of infection rises dramatically. Other issues that can affect if a person develops an infection include their nutritional status, certain illnesses and health issues (such as diabetes), smoking, and drug addiction.

Once an infection has been diagnosed, treatment includes debridement to be repeated until all dead or non-viable tissue is removed. This is followed with antibiotics. If the wound cannot be closed (skin stitched up), surgeons can choose to use a vacuum-assisted closure device, which helps protect the wound while encouraging healing.

If the bone doesn’t join at all, this is called a non-union of the bone, or an aseptic non-union of the bone. This happens in about 3 percent of all tibial shaft fractures. Non-unions can be the result of a person’s health status, just like the risk of infection. As well, some medications, such as NSAIDs (nonsteroidal anti-inflammatory drugs) and bisphosphonates, medications given most often for osteoporosis, can interfere with healing.

Total knee arthroplasties (replacements) are becoming much more common. This is due to a number of reasons, such as advances in the prosthesis and the increasing number of baby boomers who are advancing in age and who are experiencing knee problems. Once a surgery for people mainly over the age of 70, knee replacements are now becoming more common in younger adults, less than 50 years old in some cases. Unfortunately, one of the complications of knee replacements is the occurrence of infections and the number of infections remains high, from between 1 percent to 4 percent of replacements, so this issue needs to be addressed to avoid patient pain and discomfort.

It isn’t always easy to diagnose an infection in a prosthetic knee and there isn’t one particular test that is better than another to make this diagnosis. However, pre-operatively (before surgery), the synovial fluid (fluid that lubricates the joint, allowing it to move smoothly) can be tested. The results may give the surgeons an idea of who will develop an infection. The authors of this study wanted to examine the value of testing the synovial fluid in diagnosing infections.

To perform the study, researchers reviewed records of patients at three hospitals who had received a total knee replacement and then a revision, and who also had the synovial fluid of the knee examined at the time of the surgery. These patients at two of the hospitals had the fluid analyzed if here was a strong reason to suspect there was an infection and in the third, the analysis was done routinely on all patients undergoing knee replacement surgery. When examining the records, the researchers did not include any patient who had gout, pseudogout, rheumatoid arthritis, or systemic lupus erythematosus, or if a patient had a history of previous infections in the joint replacement.

The researchers declared that an infection was present if the patient met one of the following three criteria:

1- there was an abscess or sinus tract (space or channel made by the infection)
2- the culture (test) of the synovial fluid was found to have infection
3- the patient had two or more positive cultures taken during surgery

After the records of 429 knee surgeries were examined, the researchers found that 161 knees did have an infection and 268 did not. The patients were, on average 67 years old, and there was an average time of 441 days from the initial knee replacement to the revision surgery. Some of the patients, 33 percent of the group, were having a second revision done on the knee. The rest were having the first revision.

When examining the fluid, it was felt that the cut-off for determining if there was an infection was if was a certain amount (more than 1100 cells in a certain amount of fluid) of leukocytes (cells that help fight infection) and more than 64 percent of neutrophils (cells that fight foreign cells) in that same amount. A protein found in the blood that increases in the body when there is infection, c-reactive protein, was also measured. Another blood test, erythrocyte sedimentation rate, was also done.

Comparing the records showed that if the analyzed fluids fell below for leukocytes and neutrophils, it was easier to predict that an infection would not happen. But, if they were both above the cut-off, an infection was likely and most often confirmed. If the researchers looked at the neutrophil and the c-reactive protein, and they were less than the cut-offs, an infection was unlikely.

The authors of the study pointed out that there were a few drawbacks to their study. For example, the study was retrospective (looking back) so information may not be as accurate as if it was obtained by the researchers themselves. The researchers also only looked at the infection in a total knee replacement so they cannot say if these findings would work for other replacements, such as for hips. Nonetheless, the authors stated that their findings do show that it may be easier to detect an infection by combining the different cell counts and the results of the blood tests.