What has the Biggest Impact on Outcomes Following ACL Reconstruction Surgery?

Loss of knee extensionIt is no surprise that loss of motion is one of the biggest factors in patient satisfaction following ACL reconstruction surgery, specifically loss of knee extension.  In addition to the limitations in functional activities that occur with loss of knee extension, we have also discussed some of the risk factors of loss of motion following ACL reconstruction.

Loss of knee extension has a dramatic impact on gait, muscle activity, and normal tibiofemoral and patellofemoral arthrokinematics.

Imagine not being able to straighten your knee out.  You can’t lock out your knee for stability.  You naturally will shift your weight to the other extremity and overload your other knee, hip, and probably even your back.  Your quad and hamstring never get to shut off and relax.  Your patellar tendon will probably be on fire, and your patella will always be engaged and taking stress.

I can definitely see why patient satisfaction would be poor if you had long term loss of motion following ACL reconstruction!

Impact of Loss of Motion on the Development of Arthritis

In addition to poor patient satisfaction, recent research has shown that loss of motion following ACL reconstruction also results in the development of osteoarthritis.  In a recent study in AJSM, Shelbourne et al followed 780 patients for a mean of over 10 years.  They showed that of the group of patients that had normal motion on follow up examination, 29% exhibited signs of osteoarthritis on radiographs.  Conversely, 47% of the group that showed loss of motion had developed osteoarthritis.

This makes perfect sense as your arthrokinematics, center of rotation of the joint, and tibiofemoral and patellofemoral contact pressure will be altered.

How Much Loss of Extension is Significant?

More importantly, the authors also showed that even a loss of 3-5 degrees of motion had a significant impact on both patient satisfaction and the development of early arthritis.  Those subjectives that exhibited greater than a 5 degree loss of motion had an even more dramatic impact.

According to DeCarlo and Sell, the average amount of knee extension in healthy individuals is 5 degrees of hyperextension, with 95% of individuals demonstrating some amount of hyperextension in the knee.

Taking this into consideration, we should challenge the common belief that 0 degrees of knee extension is “normal.”  Individuals with 5 degrees of knee hyperextension that only restored their knee to 0 degrees of extension after ACL reconstruction surgery have a significantly greater chance of developing early osteoarthritis.

Clinical Implications

Based on these recent studies, there are bunch of clinical implications that we should all consider.  Here are just a few that I thought of right away:

  • Timing of ACL reconstruction surgery and pre-operative rehabilitation is important to settle down the knee, reduce swelling, and most importantly restore range of motion.
  • Knee extension should be restored as soon as possible after surgery, and should be one of the focuses of the initial postoperative phase
  • Even a small 3-5 degree loss of either extension of flexion range of motion has a significant impact
  • Most patients will have a certain degree of hyperextension, restoring a person to 0 degrees of knee extension is likely not enough
  • For those training post-ACL rehab clients, keep this in mind if the individual does not have full motion.  Advancing to exercises with high tibiofemoral and patellofemoral compressive and sheer forces before achieving full knee motion should be performed with caution.
  • Each patient should be assessed individually and range of motion should be restored to their unique assessment
This information also shows the importance of skilled therapy following ACL reconstruction, despite some of the studies that may show that home exercise is equally as effective.  If loss of the motion has the biggest impact on outcomes following ACL reconstruction, the development of osteoarthritis, and the subsequent health care costs, this strengthens the need for skilled manual therapy during the postopertaive rehabilitation process.

In regard to what to do with the tight person, here’s how I assess and treat loss of knee extension range of motion, but in the meantime I would love to hear what you think about this information and what you do with these patients.

Viscosupplementation for the Treatment of Knee Arthritis

Viscosupplementation is becoming a popular treatment for knee arthritis.  As rehabilitation and fitness specialists, it is important to have a clear understanding of what viscosupplementation is and what it means for our patients and clients that may be dealing with knee osteoarthritis.  There are many options, benefits, and even side effects that we should be aware of.

An Overview of Viscosupplementation for the Treatment of Knee Arthritis

Viscosupplementation is an intra-articular injection of hyaluronic acid into the knee joint by an physician.  Hyaluronic acid (also known as hyaluron and hyaluronate) is a natural substance normally found in the synovial fluid of our joints. Its function is to act as a joint lubricant and shock absorber. It has been found that patients with knee arthritis have less hyaluronic acid in their joint.(1)

The theory behind the injections is that by injecting hyaluronic acid into the knee joint, the knee will have the necessary amount of hyaluronic acid and will also help the body stimulate production of more hyaluronic acid in the joint.  This will improve patient symptoms of pain and allow for better functional mobility.

Here is an image from Genzyme, the makers of Synvisc, describing the benefit of viscosupplementation:


Viscosupplementation injections were first approved as a treatment for knee arthritis by the FDA in 1997.  The important point to remember is these injections are a treatment, not a drug or a cure for arthritis.  Hyaluronic acid injections, derived mostly from rooster combs, can provide several months of pain relief, and are given typically in a series of 3-5 injections. However, they do NOT provide any immediate effect on pain.  Success is greater for patients with mild to moderate osteoarthritis. Viscosupplement  injections can be repeated every 6 months if necessary.

Viscosupplementation Options

Currently, there are five approved viscosupplements known as the brand names Hyalgan, Synvisc, Orthovisc, Euflexxa, and Supartz.  Each vary slightly:

  • Hyalgan: First FDA approved viscosupplement; manufactured by Sanofi-Aventis; series of 3-5 injections at once per week; up to 6-7 months relief
  • Synvisc: Manufactured by Genzyme; 3 injections a week apart; 6 month relief; now with SynviscOne, a single injection for 6 month relief
  • Orthovisc: Manufactured by DePuy; Only viscosupplement not from an avian source; 4 injections with 6 month relief
  • Euflexxa: Manufactured by Ferring Pharmaceuticals; 3 injections, 6 month relief
  • Supartz: Manufactured by Smith & Nephew; 5 injections; Only viscosupplement approved to state it provides up to 12 months relief; also 3 injection series, providing 6 months relief (2)

Side Effects of Viscosupplementation

There are few side effects to these injections. Most often, there can be a local injection site reaction of redness and pain. A “hot knee” or a pseudo sepsis can also occur up to 72 hours after injection. NSAIDS, steroids, and/or arthrocentesis may be used to treat this. On a rare occasion, allergic reactions may occur. In general, this is a very safe treatment for knee arthritis.

Benefits of Viscosupplementation

A study done by Bannuru et al (3) published in 2009, compared hyaluronic acid injections to cortisone injections for treatment of painful knee OA. They found that after two weeks, the cortisone group had significantly less pain. At four weeks, both groups pain levels were the same. Finally at eight weeks, the hyaluronic acid group was significantly better than the group receiving cortisone.  This is an important point to remember when patients ask about these injections. Viscosupplements can work well, but will NOT have an immediate result.

There are also studies comparing viscosupplements to saline injections (3) that have shown no difference between groups. Therefore, I tell my patients that there is a chance these injections may or may not help, but they are safe and may prolong the need for surgical intervention.


  1. Felson DT. An update on the pathogenesis and epidemiology of osteoarthritis. Radiol Clin North Am 2004; 42:1-9.
  3. Bannuru et al. Therapeutic trajectory of hyaluronic acid versus corticosteroids in the treatment of knee osteoarthritis: A systematic review and meta-analysis. Arthritis Rheum 2009; Nov 30; 61 (12):1704-1711
  4. Lundsgaard et al. Intra-articular sodium hyaluronate 2 mL versus physiological saline 20 mL versus physiological saline 2 mL for painful knee osteoarthritis: a randomized clinical trial. Scand J Rheumatol. 2008 Mar-Apr;37(2):142-50.

Trevor WinneggeTrevor Winnegge Pt,DPT,MS,OCS,CSCS  has been practicing PT for over 10 years. He graduated from Northeastern University with a bachelors in PT and a master of science degree. He also graduated from Temple University with a Doctor of physical therapy degree. He is a board certified specialist in orthopedics and also a certified strength and conditioning specialist. He is adjunct faculty at Northeastern University, teaching courses in orthopedics and differential diagnosis. He currently practices at Sturdy Orthopedics and Sports Medicine Associates in Attleboro MA, where he uses many of these pearls of wisdom regarding viscosupplementation for the treatment of knee arthritis.

Patellar Tendon Straps Decrease Patellar Tendonitis and Patellar Tendon Strain

patellar tendon strapPatellar tendon straps, or infrapatellar straps, have been long used to decrease pain and patellar tendon strain in individuals with patellar tendonitis.  However, the exact mechanism behind why patellar tendon straps work has been unclear, despite much anecdotal reports of their effectiveness.  We have talked in the past about the effectiveness of lateral epicondyle straps, or tennis elbow straps, in reducing symptoms of tennis elbow and it is commonly reported that they reduce the strain on the extensor carpi radial brevis tendon by applying counter-force pressure.  But for some reason, there have been few studies looking patellar tendon straps.

One proposed mechanism of reducing strain on the patellar tendon using patellar tendon straps was recently assessed in a study published in Sports Health.  The authors report that past modeling of the knee suggest that patellar tendon strain at the site of patellar tendonitis increased as the angle of insertion of the patellar tendon to the inferior pole of the patella decreased.  Here is an example of the patella-patellar tendon angle (PPTA):

patella tendonitis strap

Basically, what this means is that a patellar tendon strap may reduce strain on the patellar tendon by changing the angle that the patellar tendon inserts into the patella and the length of the patellar tendon (if you really want to read the whole computational modeling study from AJSM, here it is).

Patellar Tendon Straps Reduce Strain on the Patellar Tendon

The current study’s authors sought to calculate the change in PPTA, patellar tendon length, and patellar tendon strain using two common patellar tendon straps in 20 subjects.  The two straps that were used were the Cho-Pat Knee Strap and the DonJoy Cross Strap.  Here is the Cho-Pat on the left and the Donjoy on the right:

Cho-Pat Patellar Strap DonJoy Cross Strap Patellar Strap

The methodology of the study was pretty sound and fairly complicated, enough so that I won’t go into the details here but feel free to read the entire study here.  One thing of note was that all subjects were asymptomatic males, however past studies have shown no anatomical differences in PPTA or inferior patellar pole anatomy between symptomatic and asymptomatic subjects.

Results of the study demonstrated the following findings:

  • Patella straps do alter the PPTA as well as the patellar tendon length, the authors believe that these two factors contributed to the reduction in patellar tendon strain.
  • The DonJoy strap reduced patellar tendon strain in 15/20 subjects, the Cho-Pat strap reduced strain in 16/20 subjects.  3 subjects did reduce patellar tendon strain with either strap.
  • The DonJoy strap reduced strain by an average of 34% while the Cho-Pat strap reduced strain by an average of 20%.
  • The patellar tendon straps did not significantly alter patellar tilt or congruence, so this is likely not the cause of effectiveness of Patella straps.

My Recommendations on Patellar Tendon Straps

We know that there are studies that show anywhere between 70-80% of people wearing patella straps reported improvement in both acute and chronic cases of patellar tendonitis.  It also now appears that patellar tendon straps are effective in reducing patellar tendon strain in the majority of subjects, which may be the mechanism behind the pain reduction.

One thing I did note about the study was that all participants were instructed on how to apply the straps but there was no standardized application.  For those that have used these straps, you know that you can really vary the amount of tightness of the straps significantly.  Past research on lateral epicondylitis straps have shown that both the location and tension of the strap has a significant impact in the reduction of strain.

Patella StrapThis may explain why the DonJoy strap had a much larger decrease in strain on the patellar tendon than the Cho-Pat strap.  With the DonJoy strap, you can tighten the strap as much as you would like.  You can see this well in the photo, the two straps intercross and the tightness can be adjusted.  (I should also note that “Procare” is a DonJoy company, it is the same strap).  This is the main reason why I recommend the DonJoy strap, as you can pull it really tight if you would like, but more importantly, you can adjust the tension very easily while you are wearing it.  This is helpful for everyone but especially in athletics as the strap can loosen a little with activities.  For the fitness enthusiasts, this is a cheap and simple option to at least try if you are experiencing some patellar tendon discomfort.  Check them out on Amazon for under $20.

To summarize my recommendations on patellar tendon straps:

  1. Patellar tendon straps are worth trying and may reduce pain and patellar tendon strain
  2. The location of application is likely important, try to aim for right in the middle of the patellar tendon
  3. The tightness of the strap is likely important, try to use an adjustable strap like the DonJoy Cross Strap used in this study to make sure that you can tighten it well.
  4. The DonJoy/Procare Cross Strap is pretty affordable too, here is a link to it on Amazon, try it and let me know what you think.

What has been your experience with patellar tendon straps?

Simple Exercises Can Reduce the Incidence of Patellofemoral Pain by 75%

A recent study was conducted and published in the American Journal of Sports Medicine looking at the incidence of patellofemoral pain in over 1500 military recruits undergoing a standard 14-week initial training program.  This basic military training program consisted of 3-4 hours of training daily.  Past reports have identified that up to 15% of new military recruits will develop patellofemoral pain during the initiation of basic training.  This totally makes sense as their workload likely shoots up dramatically and can be used as a great model for the observation of overuse injuries.  Just another reason to be thankful for all our troops!

The recruits were divided into two groups, the exercise group and a control group.  The exercise group began a very simple exercise program of 4 stretches and 4 strengthening exercises designed to minimize the development patellofemoral pain.  These included:

Strengthening Exercise

  • Standing isometric hip abduction against a wall
  • Forward lunges
  • Single-leg step downs from a 20cm box
  • Single-leg squats to 45 degrees of knee flexion with isometric glute contraction

patellofemoral exercises

Stretching Exercises

  • Quadriceps
  • Hamstring
  • Iliotibial band
  • Gastrocnemius

patellofemoral stretches

The strengthening exercises used body weight and progressed from 3 sets of 10 repetitions to 3 sets of 14 repetitions over the course of the 14 week program.  The isometric hip abduction exercise began with 3 sets of 1 repetition of 10 seconds and progressed to 20 seconds over 14 week.s  Stretches were held for 3 repetitions of 20 seconds over the entire 14-week duration.  Strengthening exercises were performed prior to the basic training program, while stretching exercises were performed afterward.

If we break down the exercises, we basically have a few generic stretches, an isometric exercise, and three quad exercises, one emphasizing eccentric lowering and another emphasizing concomitant glute contraction.  Pretty simple and basic.


Simple Exercises Can Reduce Patellofemoral Pain

The study intentionally characterized patellofemoral pain vaguely, which was fine with me.  Basically any type of patellofemoral pain or anterior knee pain.   Results of the study showed that 4.8% of people in the control group (i.e. no exercises) developed patellofemoral pain versus only 1.3% of people in the exercise group, or a reduction of incidence of developing patellofemoral pain by 75%.  That is a pretty strong reduction in patellofemoral pain.


What is the Take Home Message?

My first thought after reading this article was, “wow, pretty good results with such simple exercises.”  So what is the take home here?  Should we all be integrating the above exercises into our programming?  No, probably not.  My take home from all of this is actually very simple:

By performing even simple exercises, you can have a dramatic reduction in the incidence of patellofemoral pain

That is it.  I wouldn’t try to read too much into this article.  In fact, I probably would have picked 8 different exercises if I were going to design a program to prevent patellofemoral pain, wouldn’t you have?  But the results were still great.  We can only imagine what a comprehensive program would do.  Perhaps one that integrates more advanced strengthening, more emphasis on the hip, and more emphasis on balance and neuromuscular control?

Regardless, I thought this would be interesting to share and discuss to show that any exercise, even simple, is better than no exercise.

Learn more about the patellofemoral joint by downloading my eBook on Solving the Patellofemoral Mystery, free to anyone who subscribes to my newsletter – fill out the box below:

Why McConnell Patellar Taping Works

patellar tapingOne of the most common, yet least understood, treatment technique for patellofemoral pain may be patellar taping, or also referred to as McConnell taping.  First introduced in 1984 by  Jenny McConnell, a physical therapist in Australia, patellar taping has become increasingly popular.  The original intent of performing patellar taping was to alter the tilt and position of the patella, most commonly by shifting a laterally displaced patella more medially to correct patellofemoral “tracking” problems.

To date, numerous research has been conducted on the efficacy of patellofemoral taping with conflicting results.  For every study that shows altered patella kinematics, enhanced EMG and muscle function, improved dynamic alignment, and decreased patellofemoral joint reaction forces, there seems to be another study that shows just the opposite.  One thing is certain, though, most studies do tend to agree that patellar taping decreases pain in patellofemoral pain syndrome patients (PFPS).  The question is, why?

Patellar Taping – A Possible Reason as to Why it Works?

A study was published earlier this year that I think explains the mechanism by which patellar taping may work.  Actually, the authors of the study didn’t mention this mechanism at all in the paper and it really wasn’t what they studied, but after I read the article, I had one of those “Ah-Ha” moments!  I’ll explain later, but first let’s discuss the article.

McConnell Taping and Dynamic MRI

A recent study by Derasari et al in the Journal of Physical Therapy sought to examine patellar kinematics in patellofemoral pain patients after McConnell taping using dynamic MRI.  This is the first study to assess patellofemoral kinematics in 6-degrees-of-freedom during active knee extension.

14 subjects that had PFPS for greater 1 year were included in the study and underwent dynamic MRI during active knee extension with and without patellar taping.   Standard McConnell taping was apply in the lateral-to-medial direction in an attempt to glide the patella medially, such as in this photo:

McConnell Taping

Results of the study showed that patellar taping produced a significant shift of the patella in the inferior direction, not medial.  In fact, the study demonstrated that not all patients with PFPS had a laterally displaced patella to begin with, some were medially displaced.  However (and this is when the light bulb went off for me), those with a medially displaced patella actually saw a lateral shift in patella position after taping, even though the tape was applied in the standard lateral-to-medial direction.  The patella shifted against the tape direction!  This is also probably why there is so much conflicting research in the literature.

Why Patellar Taping Really Works

This study was a big “Ah-Ha” moment for me, and I think we may have found a viable reason to explain why patellofemoral taping works.  Think about it, patellar taping in the lateral-to-medial direction did cause a medial shift in the patella for those that were laterally displaced, but it produced just the opposite in people that were medially displaced, the patella actually moved against the direction of taping. Why?

After reading this study I think that taping doesn’t shift the patella in one direction, what it does is compress the patellofemoral joint.  Take a look at the figures below.  The figure on the left shows a patellofemoral joint with a laterally displaced patella, it does not sit centered within the trochlea groove.  The figure to the right is that same knee, but now with patellar tape (orange line) applied.  As you can see, it centers the patella within the groove but compressing it, the patella glides against the ridge of the trochlea:

patellfemoral joint patellar tape

The same holds true for the medially displaced patella, even if you tape in the lateral-to-medial direction, it doesn’t matter, the patellar actually shifts laterally in this case because again is glides with the trochlea groove:

image patellofemoral tape

imageThis essentially causes a “centering effect” of the patellofemoral joint by compressing it within the trochlea groove.  Subsequently, this “centering effect” increases the patellofemoral contact area, which likely has a significant impact on pain.

It is well documented that a displaced patella causes the patellofemoral contact area to decrease, causing the same amount of force to be applied to a more focal area.  By centering the patella within the trochlea, this force is distributed across a larger surface area and stress on the cartilage is decreased (for more information on this, subscribe to my newsletter and read my free eBook Solving the Patellofemoral Mystery).  As you can see in the below figures, if the same amount of force is applied to a larger area of contact, the force is distributed more evenly across the cartilage:

image image

Obviously, more research needs to be conducted, but this hypothesis seems to have some potential validity and may explain why why patellar taping works and why there is so much conflict in the literature.  If you like this kind of thing like I do, read my eBook Solving the Patellofemoral Mystery, free to all my newsletter subscribers.

Based on your experience, do you agree?  Think differently?  Why do you think patellar taping works?

Risk Factors Associated with Loss of Range of Motion Following ACL Reconstruction

image One of the most common postoperative complications following ACL reconstruction is loss of range of motion, particularly loss of knee extension.  Recent studies have shown that up to 25% of all ACL reconstructions will have a loss of knee extension range of motion postoperatively.  That seems like a pretty significant amount of people to me.

Biomechanically, loss of knee extension range of motion has some fairly serious implications.  In addition to increased patellofemoral issues and potential wear and tear to the articular cartilage, loss of knee extension creates an environment that does not allow the knee to lock into the “screw home” mechanism.  In turn, you can’t lock out your knee and your quadriceps has to fire at all times to stabilize the knee.  Over time, these patients tend to struggle with quadriceps strength gains and return to functional activities.

All this considered, as rehabilitation specialists, one of our prime concerns when working with ACL reconstructions patients has to be restoring full passive knee extension as soon as possible.  People familiar with my protocols will know that this is emphasized immediately after surgery (newsletter subscribers get a copy of my accelerated ACL reconstruction protocol for free).

Understanding risk factors that are associated with loss of motion following ACL reconstruction will allow us to identify specific patients that are at great risk.

It has been documented that preoperative range of motion is highly correlated with postoperative range of motion, meaning that the more motion you have going into surgery, the more you’ll have after surgery.  This has led to a trend of delaying surgery to allow the knee to “quite down,” so to say, and allow for the reduction of effusion and inflammation. 

A new study set to be published in an upcoming issue of the American Journal of Sports Medicine has also identified that the presence of a bone bruise also correlates with loss of motion.  In this study, 75% of patients with preoperative loss of motion and 46% of patients with a bone bruise on the lateral femoral condyle and lateral tibial plateau presented with delayed range of motion recovery.  Considering that past studies have shown bone bruises to be present in 70-80% of ACL injuries, this is a significant finding.


Clinical Implications

My personal belief is not that one has to wait a certain amount of days before they have surgery, but rather that they have to wait until they are “ready” for surgery.  What does that mean to me?  Well, here is my criteria of a knee that is “ready” for surgery:

  • Minimal effusion and inflammation
  • Full knee extension and good flexion range of motion
  • Volitional control of the quadriceps – i.e. they can actively contract the muscle with out an extension lag
  • Normal gait without an antalgic limp or quad-avoidance pattern

Patients with bone bruises tend to have more pain, swelling, and inflammation.  These patients may require a little longer preoperative period to assure that their knee is “ready.”  Again, I feel that he duration should be individualized.  But, the results of this study make sense to me.

I would also recommend trying to find out if your patient had a bone bruise.  Ask the surgeon or even the patient.  Try to get a copy of the operative note and MRI radiology report.  This is valuable information as you will know what to expect if your patient appears to be struggling postoperatively.  We should be extra cautious that these patients restore extension range of motion as soon possible after surgery.  Perhaps these are the patients that get a few more visits scheduled during the early phases of rehabilitation or get prescribed more frequent stretching as part of their home exercise program.

What do you think?  How would you treat someone with a bone bruise differently?

Meniscus Repair or Meniscectomy? Comparison of Long Term Outcomes

image There is an interesting study about to come out in an upcoming article in the American Journal of Sports Medicine comparing the outcomes of arthroscopic meniscus repair and partial meniscectomy. 

The authors compared 42 patients undergoing meniscal repair to 39 patients undergoing partial meniscectomy at a mean of 8.8 years after surgery.  The authors specifically evaluated osteoarthritic progress, loss of knee function, and influence on sports activities.  The authors did a good job controlling the study by excluding knees with instability and only including medial meniscus tears.  However, the study was no completely randomized, the decision to perform a repair versus meniscectomy was based on the type of meniscus tear present.


Arthroscopic Meniscus Repair Surgery Video

There are some pretty neat videos on YouTube of meniscus repairs, thought this would be a good place and time to include one here:



Results of the study were interesting:

  • 81% of patients having a meniscus repair did not show any significant osteoarthritis at the time of follow up, while 60% of meniscectomy patients did show osteoarthritic changes.
  • Functional scores showed no difference between the two procedures, however 94% of meniscal repair patients returned to their previous level of sport activity compared to only 44% of the meniscectomy group.
  • There was a significant drop in sport activity in the meniscectomy group only.


Clinical Implications

Personally, I wasn’t very surprised at the large difference between groups.  It is obvious that the mensical repair procedures are fair superior to partial meniscectomy.  It is well established that preserving as much as the meniscus as possible will yield greater results over time.  The menisci play a very important role in shock absorption and the normal biomechanics of the knee. 

There are many pros and cons to both procedures, and the postoperative recovering is certainly longer following meniscal repair, however the results of this study certainly show that pros should outweigh the cons.  It should be noted that sometimes a repair is not always feasible and meniscal damage of this nature will likely result in osteoarthritic changes over time, potentially explaining the results of this study.

What I take away from this study is more educational that clinical.  I am not sure that there is anything we can do differently to enhance outcomes in meniscectomy patients based on this study, but the results do underscore the dramatic importance of the meniscus on knee function.

Imagine that it was fairly common to perform a COMPLETE meniscectomy only a few decades ago!

How Soon Should You Have Surgery After a Multiple Ligament Knee Injury?

            knee dislocation mri      knee dislocation x-ray

Today’s post is another research update by Dan Lorenz on the effect of surgical timing in multiple ligament knee injuries.  There are pros and cons to both acute and chronic reconstruction.  My experience has always been to be about the middle of the road, get them early but let them settle down a bit first, then get rehab going fast.  Thanks again Dan!



Dan Lorenz, PT, DPT, ATC/L, CSCS

Mook et al recently did an interesting systematic review of studies to compare outcomes in early, delayed, and staged procedures as well as the subsequent rehabilitation protocols. Twenty-four retrospective studies were analyzed involving 396 knees dealing with multiple ligament knee injuries involving both cruciates and either or both collaterals. Data were compared as follows: 1) acute (time to surgery <3 weeks), 2) chronic (time to surgery >3 weeks), and 3) staged treatment (combination of repair and reconstruction in the acute and chronic periods). Findings were as follows:

  • Anterior instability – Acute treatment lead to greater instability compared to chronic treatment. No differences were found between acute and staged or staged and chronic. No differences in anterior instability were garnered from postoperative rehabilitation.
  • Posterior instability – Posterior instability was found in 28% who were managed with immobilization compared to 12% of those managed with early mobilization.
  • Varus laxity – Acute treatment resulted in 21% of patients having laxity in the immobilized group compared to only 1.6% managed with early mobilization. In the chronic treatment group, varus laxity was found in 1% managed with immobilization compared to 20% managed with early mobilization.
  • Valgus laxity – Acute treatment resulted in 26% of patients having laxity managed with immobilization compared to 2% of those managed with mobilization.
  • Flexion loss >10° – Significantly more patients (31%) had flexion loss of >10° in the acute group compared to patients in the chronic group. Significantly fewer patients were found to have flexion loss when managed in stages compared to those managed acutely. Flexion loss >10° was reported in 48% of those who were immobilized compared to 28% of those who were allowed early immobilization.
  • Extension loss of >5° – no differences were found based on surgical timing, but 15% of patients immobilized compared to 5% who were allowed early mobilization showed extension losses.
  • Good or excellent subjective outcome scores – Significantly greater outcomes were found in the staged group compared to the chronic group and the acute groups.
  • Abnormal/poor subjective outcomes – Significantly more poor outcomes were found in those managed with immobilization compared to those who were allowed early mobilization.
  • Lysholm Score – no differences in timing or rehab
  • Return to work – acutely managed patients who were immobilized early were significantly less likely to return to work than those who were mobilized early. No differences were found on basis of surgical timing
  • Return to athletics – patients who were managed acutely were significantly less likely to return to athletics than those who were managed in stages.
  • Operative arthrolysis – significantly fewer patients in the chronic treatment group underwent manipulation when compared to both the acute and staged treatment groups.


Clinical Implications

From a rehab standpoint, researchers found that those managed acutely with early mobilization had better outcomes as well as less range of motion losses. Observations from the researchers include a few important points. Reconstruction within three weeks after injury results in more anterior instability, more severe ROM complications, and more need for MUA. Secondly, they found patients that are managed in stages had the highest percentage of excellent/good subjective outcomes and the least ROM deficits. Third, although final ROM was preserved best in patients undergoing staged treatment, a high percentage needed follow-up surgery due to arthrofibrosis. This finding suggests that simultaneous repair and reconstruction of the cruciates acutely may lead to substantial ROM deficits and are unresponsive to follow-up surgery. Next, aggressive rehabilitation with early mobilization is associated with less ROM complications and earlier return to work, particularly in those who are acutely managed.

In conclusion, researchers stated:

  • Delayed surgery potentially results in equivalent stability measures compared to acute surgery.
  • Staged procedures produce a better subjective outcome and lower number of ROM deficits, but still needed additional treatment due to joint stiffness.
  • Patient managed acutely are as likely as those who are managed in stages to require additional treatment due to ROM deficits.
  • For the acutely managed patient, early mobilization results in better outcomes.
  • The type of rehab for delayed procedures isn’t as important as those who are managed acutely (mobilize acute early).

Does anyone have any thoughts on this study that they would like to share?  Any experiences?



Mook WR, Miller MD, Diduch DR, Hertel J, Boachie-Adjei Y, & Hart JM (2009). Multiple-ligament knee injuries: a systematic review of the timing of operative intervention and postoperative rehabilitation. The Journal of bone and joint surgery. American volume, 91 (12), 2946-57 PMID: 19952260