Panel discusses treatment of ACL injuries in athletic patients: Part 2

In the second part of this Orthopedics Today Round Table, orthopedic surgeons and physical therapists share how to most effectively treat patients with ACL injuries. I hope you find this Round Table interesting, insightful and useful to your practice. Click here, to read the first part of the discussion.

Kevin E. Wilk, PT, DPT, FAPTA
Moderator

Kevin E. Wilk, PT, DPT, FAPTA: Immediately after surgery to reconstruct the ACL, when will you push for full passive knee extension? How much extension or hyperextension do you want?

Frank R. Noyes, MD: Our program is to achieve a normal 0° to 5° hyperextension, but not to achieve 5° to 10° hyperextension. Even though the opposite knee, for example, has 10° hyperextension, this represents a physiologic posterolateral laxity which can initially overload the ACL graft.

K. Donald Shelbourne, MD: I push for full passive knee extension, equal to the opposite knee, immediately after surgery. This is my goal regardless of the degree of hyperextension present in the other knee. My goal is to return the patient’s knee to its normal state, which varies from person to person. If a patient has 7° of hyperextension in his normal knee and you only permit them to go to full extension (0°), then this is a significant side-to-side difference that will limit the patient in his return to activities, and has been associated with a higher rate of long-term radiographic changes. I believe that in the long-term, patients would tolerate chronic ACL deficiency better than they would tolerate loss of knee range of motion (ROM) resulting from ACL reconstruction. We must be careful not to provide stability at the expense of ROM.

James R. Andrews, MD: As I said, we start full passive knee extension the morning after the surgical procedure. I do not worry about hyperextension unless they are in a symmetrical sport, like ballet, so we just go to full extension and work from there.

Robert E. Mangine, MEd, PT, ATC: Our current opinion on extension is permitting 0° as soon as the athlete can tolerate the position, but emphasize the need to have full active extension control by 3 days after surgery. We utilize an unlocked brace for walking activity, but the brace is removed when performing exercise to avoid the inhibition of motion. Although it is old fashioned, we still utilize a continuous passive motion (CPM) approach — especially when the patient is sleeping, to facilitate joint drainage, articular cartilage nourishment and joint capsule response to control pain.

The literature is clear that full active extension with proper graft placement and tensioning is non-deleterious to the ACL. As for pushing extension past 0°, we will control this position for 3 weeks to 4 weeks then allow the amount of hyperextension be achieved by the athlete naturally. With aggressive return-to-play concepts and high force placed on the ACL in the hyperextension position mechanically, it may place the athlete in a non-athletic position.

Russ M. Paine, PT: We discuss early rehabilitation goals with patients upon their initial visit the day after ACL reconstruction. Their first goal is to gain full extension as soon as possible. We strongly believe the quickest way to gain extension is through quadriceps activation. We utilize a biofeedback device and initial instructions the day after surgery are to “tighten your quad and force the back of your knee straight.” Patients are educated and informed that the pain experienced during this activity is not harmful to the repair or reconstruction performed to knee joint. This information is crucial for patient compliance and motivation to remove fears that an activity, such as forcing knee extension, is not injurious to their knee.

Gaining full extension is our primary goal. If hyperextension occurs during quad setting with forced knee extension, then there is no limit to active hyperextension. There are no efforts to passively force the knee into hyperextension. We often see that such hyperextension may return when patients begin the “return to function” phase of their recovery

James J. Irrgang, PhD, PT, ATC: We generally want knee extension symmetrical to the contralateral knee unless the contralateral knee is grossly hyperlax, i.e., greater than 10° hyperextension. Assuming the graft is anatomically positioned with good fixation, we would want to achieve this within 2 weeks to 3 weeks of surgery.

Wilk:What are the primary rehabilitation goals for the patient during the first week after surgery?

Paine: The primary goals during the first week after ACL reconstruction are:

• initiate quad function;
• gain full extension of the knee;
• begin to assume a normal gait with no limping with crutches. Patients are allowed to discontinue crutches when they can ambulate without a limp and have no giving-way episodes due to weakness;
• control postoperative swelling; and
• initiate balance and proprioceptive stimulation.

It is to be noted that we do not force for flexion of the knee, but rather allow this to occur more gently than extension of the knee. Forcing for flexion can often cause an increase in swelling of the knee.

Noyes: The first week includes elimination of postoperative swelling and edema by stressing limb elevation, compression and ice modalities at home and in clinic. Return of a voluntary isokinetic contraction of the quadriceps/hamstrings, gentle assisted ROM, crutch ambulation with partial weight-bearing and gentle closed chain. Allow time for postsurgical inflammation to resolve to set-up the second and third week rehabilitation program.

Shelbourne: Perform exercise sessions three times to 4 times per day to achieve the following goals:

• achieve full, symmetric knee extension compared to the opposite, normal knee;
• maintain good quadriceps muscle control (straight leg raise and active heel lift);
• steady improvement in flexion ROM;
• maintain full-knee flexion in graft knee (contralateral graft only) and initiate high-repetition, low-load strengthening exercise program through use of a shuttle leg press machine; and
• control the effusion and prevent a hemarthrosis through constant use of a cold-compression device, constant elevation of the knee above the heart in a CPM set from 0° to 30°, ambulation limited to bathroom privileges only, use of anti-embolism stockings; and full weight-bearing gait with assistive device if needed for balance. Use as normal of a gait pattern as possible with shorter, slower steps.

Andrews: For me, maintaining and getting full extension of the knee are the primary goals for the first 2 weeks. Obviously you are working on flexion, too. The problem is that if you get behind with extension, it is hard to get it back. If you get behind with flexion, then you usually can catch that up. Extension though can become a problem. We like to make sure patients are doing prone lying with weight hanging off their ankle over the end of the table as soon as we seen them having a struggle with lack of extension.

Mangine: No phase of rehabilitation for the ACL has dramatically changed from 1970 to current day. Prior to our published report in 1984, the dominate method was to immobilize the joint for 4 weeks to 8 weeks. As the surgical body of knowledge progressed, the ability to initiate early protective motion was advanced to now allow – as the athletes surgical complaints decrease – the ability to have 0° to 130° of motion within the first week. This facet of the rehabilitation was dependent on the surgical techniques advancement, more so than rehabilitation interventions. The three key elements included placement, graft quality and graft stabilization.

Currently, we progress full active motion by the end of the first week to assure control of the extensor mechanisms regaining the ability to control patella position and regain muscular motor control of the joint. Although I will, in all likelihood, be the only one to recommend the continued use of CPM devices, our rationale is based on the fact that CPM is not detrimental to the ACL. All studies to date on CPM show positive value on the articular cartilage, which is often involved in athlete injuries. Pain and postsurgical swelling control go hand-in-hand. Both must be addressed and controlled for improvement in ROM and regaining muscular control. Both pain and joint swelling inhibit muscular function by way of the “H” reflex creating a dampening effect of the extensor mechanism and the athlete’s ability to move the joint.

As far as I am concerned the use of crutches should be reinforced as we permit early weight-bearing, but emphasize correct gait patterning to facilitate both ROM and muscle reactivation. In some cases, I may maintain the use of crutches as long as 3 weeks or until the patient demonstrates a normal gait pattern.

Irrgang: The primary rehabilitation goals during the first week after surgery are decreased pain and swelling, 0° knee extension (progressing toward extension symmetrical to the contralateral knee, including hyperextension), 90° knee flexion, good/strong quad set that results in superior migration of the patella, and the ability to perform a straight leg raise test without a lag, no/minimal inflammatory reaction after exercise.

Wilk: What are the key areas of principles that must be addressed during the rehabilitation process to ensure an optimal outcome?

Noyes: There are many in the functional progression and to be brief:

• prevent arthrofibrosis and the stiff knee including normal patellar mobility;
• initiate early muscle strength closed/open chain to prevent early muscle atrophy that may occur within 2 weeks to 3 weeks of surgery;
• neuromuscular control with early isokinetic and proprioception training;
• delay return to strenuous athletics until all normal parameters as above. Remember repeat ACL tears to the operative or nonoperative knee are as high as 10% to 12%; and
• a neuromuscular training program in all female athletes.

Andrews: Key areas you have to be careful with in the rehab process are maintaining an adequate ROM, aggressively getting the quad going immediately, maintaining and working with passive patellar mobilization, and the prevention of swelling and hematoma formation. Also, there are steps that obviously should be in an orderly step-by-step progression. You do not want to get athletes running too quickly, particularly if they have weak quadriceps. If they start early running, particularly when you use a patella tendon and their quad is overloaded and the patella tendon defect gets over loaded, they will get patella tendonitis postoperatively. All of those things are related to appropriate rehab with a knowledgeable physical therapist. The rehab and a knowledgable physical therapist may be more important than the surgical procedure itself.

Paine: The keys for optimal outcome are multifactorial and, most importantly, require much energy and time from both therapist, trainer, physician and patient. Although there are always exceptions to the rule, most of our successful outcomes are seen in patients who put forth the substantial effort required to achieve the ultimate goal — return to the prior, or in some cases, higher level of function. Most patients underestimate the time required to make such a recovery. Another key principle we have instituted is follow-up or re-check day. This is done one time per week where the physician, therapist, fellows, residents and medical office staff interact with the patient. It may not be feasible in all orthopedic practices, but some form of tracking patient progression improves outcomes. This was a key principle of Jack Houston, MD, carried on by Drs. Andrews and Wilk. Dr. Lowe and I instituted this “team” approach several years ago and believe it has upgraded our program.

Understanding, identifying and linking with the top individual rehab professionals in your community and beyond who have the skills to move ACL patients through the appropriate rehab progression is of vital importance. Obviously restoring motion, strength and confidence (proprioception) are key principles. We also perform a series of functional tests prior to return to activity that provides data to grade the athletes’ level of condition.

Irrgang: The key areas that must be addressed include the restoration of full motion symmetrical to the contralateral knee; greater than 90% quadriceps strength; improved trunk and hip control/stability; gradual criterion-based functional progression and return-to-sport progression that respects graft healing.

Mangine: The body of knowledge about the ACL has expanded to the point of constant redundancy in the literature. Although we continue to expand the evidence base of the treatment of ACL injuries, much of the historical data has been the foundation for the success we see today. Our approach has evolved during the past 32 years, which we defined as the “evaluation-based model” of rehabilitation. The design was to account for multiple athlete variables that influence athletes’ speed of progression to return to sports. Post-surgical progression is a parabolic curve. Overall, 10% of athletes have the potential to stretch their grafts within the first 12 weeks, while 10% have the potential to develop motion complications. The role of rehabilitation is to constantly evaluate the athlete to determine the direction and speed of the program.

Factors we consider include:

• surgical technique, graft size, position, stabilization method and secondary procedures;
• soft tissue healing. Athletes may have variances in collagen types, which require constant monitoring to avoid collagen stretching or motion complications;
• ROM. I believe in CPM as a tool to assist in regaining motion, but the era of avoiding terminal extension have long been over even for early resistance training;
• regaining muscle control. The evolution of techniques that allow for early initiation of muscle re-education and strengthening programs have advanced to guard the safety of the graft while progressing the muscle back to normal;
• joint stability. The use of joint arthrometer testing has become a non-factor by many clinicians, but still serves as an excellent tool to determine speed of progression;
• joint neurology. Clinicians must gain an understanding of the mechano-receptor system, as with the injury and graft reconstruction of the ACL. No study has shown that the native mechano-receptors will regenerate into the reconstructive graft; and
• psychological progression. Many athletes suffer the sequence of events associated with acute trauma. This aspect may be as important as any physical element of the rehabilitation process. A positive, goal-driven program must be outlined for the athlete to maximize the potential for return. This requires the clinician to spend the necessary time to educate the athlete on their progress and the rationale behind it.

Shelbourne: The most important principle is to restore full symmetry compared with the opposite, normal knee. This starts with regaining full knee extension, including hyperextension, first, followed by knee flexion, and finally symmetric strength. This is the foundation needed to allow patients to feel as if they have a normal knee and return to full activities without favoring the knee.

Wilk: When do you know a patient is ready to begin a running program, specific sport drills, return to practice and return to competitive sports?

Shelbourne: I believe this might be the topic from my Accelerated Rehabilitation publication that gets misinterpreted the most. It seems to be common thought that running is allowed earlier with this protocol. In fact, running for the sake of running is one of the last things we recommend due to the repetitive impact associated with this activity. Athletes benefit more from and are able to tolerate sport-specific drills, practice and even scrimmage/competition sooner than they can tolerate a high volume of straight-line running. A high volume of training with running usually leads to soreness and swelling in the months after ACL reconstruction. So we recommend that low-impact forms of exercise be used for cardiovascular conditioning (cycling, elliptical and swimming), and the patient be gradually re-introduced to impact activities and change-of-direction through sport-specific activities.

The criteria for determining readiness involves looking at swelling control, ROM symmetry, strength symmetry and strength compared to preoperative values. I have had patients with good swelling control and ROM who were able to do some very low-level sports activities (shooting free throws) as early as 2 weeks to 4 weeks after surgery. I recommend that any impact activities (running or jumping) or drills involving change of direction be delayed until symmetric ROM and strength is restored.

We use isokinetic testing at 60°/second and 120°/second and the single-leg hop tests to determine strength symmetry. Prior to releasing to a return-to-sport progression, we like to see side-to-side strength within 10% when compared to the opposite knee and at least 80% when compared to preoperative values. Oftentimes, patients need to limit impact activities to every other day for a period of time to prevent escalating swelling or tendon soreness.

Noyes: We initiate a functional progression program and have published our specific return-to-play criteria. The return to play criteria should include the following tests and potentially others we have listed in our publications: knee exam, isokinetic strength test, jump analysis, hop test, single-leg squat, vertical jump, core strength, and cutting drill. Be very careful in starting plyometric and jump training. You will pick up early athletes who are unable to do a single-leg hop test and require extensive neuromuscular training even though they have normal hamstring/quadriceps strength. We also have an emphasis on return of hip and core strength.

Andrews: You have to start them off in progression fashion. You generally start walking on a treadmill, then run lightly on a treadmill or an altered G. We will, when available, have them walk and run on a treadmill underwater in a pool. Once the athletes are doing that — and their quad looks good, with good quad strength and they pass the clinical evaluation by the therapist — the physician will allow a running program. The problem is beginning a running program too quickly. When athletes do a running program, you need to make sure they do not run up and down steps or run on uneven surfaces or hard concrete. It is a gradual step-by-step process which leads to a real running program. Initially, there are no cuts being made. If there are questions, we fit the athlete with an ACL brace.

Paine: We allow patients with patellar- tendon graft (PTG) ACL reconstruction to begin a running program at 10 weeks postoperatively. For them to be able to run, they must be able to perform a single-leg squat equal to the normal side. Manual isometric muscle testing is performed at 65° on quads and hamstrings and be nearing 70% of normal. Running is performed on a treadmill for 2 weeks before outdoor running is allowed. We allow jump rope at this same time frame. Sport-specific drills are begun after 4 weeks of running has been completed. Return to practice without full contact averages around 5 months for PTG. Prior to full competition at 6 months, we perform a series of functional tests to ensure level of readiness.

Irrgang: Running is started when the patient has 80% quadriceps strength and can walk at a fast pace for 15 minutes with no gait deviations or signs of inflammation. Generally, we expect this to occur approximately 4 months to 5 months postoperatively for most patients. Low-level agility drills (ladder drills, etc.) begin when the patient has greater than or equal to 85% quad strength and is able to run 1 mile to 2 miles without gait deviations or signs of inflammation.

Patients are progressed to jumping (take-off and landing on both feet) when they are able to perform full-effort agility drills without deviations or signs of inflammation. When the patients achieve 90% quad strength and demonstrate the ability to jump at full effort without symptoms or deviations, they are progressed to cutting, pivoting and hopping (take-off and landing on one leg). Patients return to practice when they are performing all sports-specific drills at full effort, without deviations or symptoms and they are able to pass a battery of performance-based tests including single, triple, triple cross-over and timed-hop tests and a variety of running/sports specific drills (pro-agility tests etc.) Patients start with limited practice and gradually return to full practice and then to competition.

Mangine: The athlete’s advancement through a functional progression requires the clinician to incorporate multiple evaluation techniques as well as subjective assessment. Although, over the years elaborate algorithms have been published and analyzed, clinicians still need to assess the joint manually, skill mechanics and practice functions visually and not just have the athlete advance without direct observation. Our running program requires muscular control of the joint with step-downs, normalizing the overhead squat position, muscular strength in the 30% range and quadriceps/hamstring ratios of 1:1 since the hamstring dominates the extensor mechanism in the early phase of rehabilitation.

However, our objective muscular strength parameters are not a hard-and-fast rule. There should be minimal, to no joint effusion due to an inhibitory effect on muscle function. Although not emphasized today, joint arthrometer evaluation is still utilized to verify manual examination. A key element is the athlete’s psychological status as injury and surgery may reduce the athlete’s desire to resume return-to-play functions. Advancement to skill drills progresses as strength develops and, in our system, this is measured based on our squat exercise advancement program, consisting of: front squats, box squats, back squats, single-leg step-ups, eccentric step-downs, overhead squat, bell squats, and variable squats (chain or band). Critical for the prevention of re-injury is control of lateral functional mobility with associated rotation activity. This functional movement is assessed based on power and speed in drills such as a shuttle run and star drill, which need to be within 85% of pre-injury level.

Finally, we continue to utilize the functional hop program including distance, 6-meter timed hop and cross-over hop. As the athlete completes each phase, there is no predictable time period as it is a parabolic curve with some individual’s ability to return-to-play as early as 16 weeks, while others require a full year.

Wilk:What is your biggest concern for a patient following ACL reconstruction and returning to sports?

Irrgang: Our biggest concern with return to sports is re-injury to the ipsilateral or contralateral knee. In addition, we are concerned the development or persistence of symptoms (pain, swelling, instability), which may indicate there are untreated impairments of the knee. Ultimately, we are concerned with the long-term health of the knee and avoidance of the development of post-traumatic knee osteoarthritis.

Andrews: My biggest concern is returning an athlete too early and having a graft failure. My other concern is using allografts in high-level athletes, particularly young athletes. If you think you can return them quicker with a cadaver graft, that is not true. It takes longer for an allograft to mature than it does an autograft. So my biggest concern is retears of any graft by coming back too soon. Of course as I tell patients, you can tear up anything, including a grafted ACL. The other big problem is athletes tearing their opposite ACL. All of these things worry me.

Noyes: My biggest concern is a return to competitive sports too soon, which risks a repeat injury prior to return of neuromuscular control and achieving normal performance enhancements. An elite athlete will always say it takes many months after ACL surgery to be back to normal. A repeat ACL tear is a nightmare to avoid. High school female athletes require a 6-week neuromuscular program and we have published extensively on the non-profit Sportsmetrics neuromuscular training program.

Shelbourne: I believe many risks of re-injury can be mitigated by ensuring full, symmetric ROM and strength are regained prior to initiating the return-to-sport progression. This is required for the patient so they feel they have their normal knee back and allows them to regain normal activity levels without movement compensations.

Another priority is working with the athlete, athletic training staff, coaches and parents to help them understand that returning to sport is a process. Even though the athlete may have a good foundation to perform all the sport-related tasks, it may need to occur on an every other day basis at first to allow them to acclimate to the sport without setbacks due to swelling or tendon soreness.

Paine: Our biggest concern is re-injury to the reconstructed ACL graft. We try to cover all bases including hip/core strengthening, plyometric jumping for those involved in jumping sports, and making sure the rehabilitation process has been completed before allowing athletes to return to sports. Far too often I see both professional and amateur athletes who have not completed the milestones required for a successful return. The lack of strength prior to return often results in chronic swelling of the knee, patellar tendonitis and increased risk of re-injury to the healing graft.

Mangine: ACL surgical intervention regardless of tissue type, graft position, and stabilization method results in altered structural integrity as compared to the native ACL. Even though it is now considered a routine procedure, alterations to the joint mechanics occurring at the joint surface, loss of critical mechanoreceptors within the native ACL and changes in the surrounding capsule-synovial environment may not return to normal. Although much work has been accomplished in the three key areas of surgical intervention, rehabilitation procedures and performance training in a native environment still do not exist. The literature is clear that even after ACL surgery and restoration of “normal soft tissue structure” the potential for arthritic changes is not predictable. Further, restoration of a harvested graft, although demonstrating structural remodeling, lacks literature support demonstrating a neuro-mechanical restoration, leaving the knee at risk of repeat trauma. Currently, a criticism of sports is the natural overuse tendency. After surgery, this may be magnified and arthritic changes have been documented after ACL surgical intervention.

Wilk: Thank you to the panel of experts for their time and willingness to share their opinions, expertise and experiences in the treatment of patients with ACL injuries.

References:

Barber Westin SD. Arthroscopy. 2011;doi:10.1016/j.arthro.2011.09.009.

Barber Westin SD. Phys Sportsmed. 2011;doi:10.3810/psm.2011.09.1926.

For more information:

James R. Andrews, MD, can be reached at the Andrews Institute for Orthopaedics & Sports Medicine, 1040 Gulf Breeze Pkwy., Suite 203, Gulf Breeze, FL 32561; email: info@theandrewsinstitute.com.

James J. Irrgang, PT, PhD, ATC, FAPTA, can be reached at the University of Pittsburgh, Department of Orthopaedic Surgery, Suite 911 Kaufmann Medical Building, 3471 Fifth Ave., Pittsburgh, PA 15213, email: irrgangjj@upmc.edu.

Robert E. Mangine, MEd, PT, ATC, can be reached at 2920 Scioto Hall, Room 108, Cincinnati, OH 45267; email: manginre@ucmail.uc.edu.

Frank R. Noyes, MD, can be reached at Cincinnati Sports Medicine & Orthopaedic Center, 10663 Montgomery Rd., Cincinnati, OH 45242; email: frnoyes@fuse.net.

Russ Paine, PT, Memorial Hermann Hospital, 6400 Fannin St., Houston, TX 77030; email: russpaine@sbcglobal.net.

K. Donald Shelbourne, MD, can be reached at Shelbourne Knee Center, 1815 N. Capitol Ave., Indianapolis, IN 46202; email: acldoc@aol.com.

Kevin E. Wilk, PT, DPT, FAPTA, can be reached at Champion Sports Medicine, 805 St. Vincent’s Dr., Suite G100, Birmingham, AL 35205; email: kwilkpt@hotmail.com.