A Perioperative Rehabilitation Program for Anterior Cruciate Ligament Surgery
Todd Arnold, MD; K. Donald Shelbourne, MD
THE PHYSICIAN AND SPORTSMEDICINE - VOL 28 - NO. 1 - JANUARY 2021
In Brief: Rehabilitation programs have progressed alongside surgical advances in anterior cruciate ligament reconstruction. A perioperative program has been successfully used at our clinic for more than 10 years to reduce postoperative complications and return patients to activity safely and quickly. The four-phase program starts at the time of injury and preoperatively includes aggressive swelling reduction, hyperextension exercises, gait training, and mental preparation. Goals after surgery are to control swelling while regaining full knee range of motion. After quadriceps strengthening goals are reached, patients can shift to sport-specific exercises.
Anterior cruciate ligament (ACL) ruptures occur at a rate of 60 per 100,000 people per year (1). With society's increasing interest in physical fitness, primary care physicians are seeing more athletic injuries, some of them ACL ruptures.
At our center, the rehabilitation program for patients who have had ACL reconstruction is distinguished by a four-phase perioperative rehabilitation program (table 1) that facilitates and expedites patients' return to their desired activities and lifestyles. The program can be used safely without compromising the initial goals of surgery, such as restoration of knee stability, full range of motion, and normal function (2).
Phase 1: Preoperative Preparation
The first phase of rehabilitation is the same whether the patient's choice is to undergo ACL reconstruction or to modify activities to accommodate an ACL-deficient knee. The primary care physician can initiate most of these steps until a consultation with an orthopedic surgeon is obtained.
Preoperative counseling. After the ACL tear diagnosis, patients are counseled about the risks of meniscal tears and joint deterioration in ACL-deficient knees when jumping, twisting, or engaging in pivoting sports or heavy labor (3). The important points to remember are that ACL reconstruction is not an emergency for most patients (except those who also have lateral side knee injuries) and that achieving all the preoperative goals can greatly reduce or eliminate range-of-motion complications after surgery (4,5).
Physical therapy. The initial goals of rehabilitation are to reduce swelling, return knee range of motion, and restore normal gait pattern. The time needed to accomplish these goals can be as little as 1 week or as long as 2 months, depending on how the knee responds to the initial injury.
To reduce swelling, a cold compression cuff (Cryo/Cuff, Aircast, Inc, Summit, New Jersey) is applied to the knee and filled with ice-cold water (figure 1) The patient can wear the cuff continually except when walking. Swelling reduction eases the return of normal range of motion (full hyperextension and flexion equal to the noninvolved knee).
Extension is measured with the patient lying supine with the heel on a bolster so that the knee hyperextends, if possible. Hyperextension is regained by doing heel-prop (figure 2a) and prone-hang exercises (figure 2b). When regaining extension is difficult, a hyperextension device may be used for 5 to 10 minutes several times a day (figure 3). A previous study (6) has shown that obtaining full hyperextension preoperatively dramatically reduces scar tissue formation within the knee (also known as a cyclops lesion, a focal nodule of fibrous tissue in the intercondylar notch anterior to the reconstructed ACL) postoperatively and prevents anterior knee pain (7). Effusion reduction allows the return of flexion, and the heel-slide exercise can reproducibly promote full flexion. The latter is done while sitting; the patient slides his or her heel toward the buttocks.
Gait training can begin when the patient can withstand pressure on the leg with the use of crutches. A normal heel-to-toe crutch pattern is taught, and patients use that pattern until they can walk normally without crutches.
Mental preparation. Patients who have had ACL ruptures have experienced a loss, specifically of participation in athletics and potentially in social circles, and should be allowed time to deal with this aspect of the injury. The physician's role here is to be observant of the patient's attitude. Typical responses of anger, denial, depression, and, finally, acceptance are to be expected. Postinjury rehabilitation allows patients to work through these feelings (8).
Mental preparation for the surgery cannot be understated. We want patients to have a positive outlook for surgery and to prepare to work hard after surgery. Mental preparation therefore includes educating patients about the injury, surgery, and rehabilitation goals. Knee anatomy and ACL function are carefully explained before surgery. Once surgical reconstruction is elected, the rehabilitation goals and their rationale are discussed. A booklet covering the same information is given to patients to review at home. To facilitate rehabilitation during the first postoperative week, we request that caregivers assisting patients after surgery be present during educational sessions.
Once swelling has resolved and full motion has returned, surgery can be scheduled around school, work, and social schedules. Because it allows adequate devotion to rehabilitation, appropriate surgical timing can drastically reduce the incidence of postoperative complications of arthrofibrosis and strength loss (5,8,9). Each phase of rehabilitation is carried out at home. Patients are seen at 1, 2, 4, and 8 weeks postoperatively; physical therapy is advanced at these times based on goal achievement.
Patients who do not elect surgery or who want to postpone surgery for several months are counseled to avoid jumping, twisting, and pivoting, because these activities increase the patient's risk of additional joint damage and meniscal tears (6).
Postoperative rehabilitation consists of two parts. The first part of rehabilitation focuses on returning the knee to a quiescent state by eliminating hemarthrosis and pain while achieving full knee motion. The second part of rehabilitation involves donor-site strengthening, first with full flexion exercises to pull the patellar tendon to length, then with repetitive strengthening exercises to stimulate tendon regrowth. The first part of rehabilitation takes precedence over donor-site strengthening because aggressive strengthening may cause painful swelling that may limit motion.
Phase 2: Week 1 Postsurgery
Hemarthrosis control. To prevent hemarthrosis, a cold compression cuff is placed on the ACL-reconstructed knee immediately after the wounds are closed and a light dressing is applied. The control of hemarthrosis is also enhanced by the use of a continuous passive motion (CPM) machine, which decreases venous pressure by elevating the joint above the level of the heart (figure 4) (10). The machine is set to move from 0° to 30° of flexion and is used continuously the first week after surgery except during rehabilitation exercises. Severe activity restriction and knee elevation both help control swelling.
Rehabilitation exercises. Exercises for regaining full range of motion are begun the day of surgery. Hyperextension is maintained with 10 minutes of heel prop exercises every waking hour. Flexion exercises are performed six times daily. This can easily be done by slowly increasing flexion of the CPM machine to the point of tightness and holding the position for several minutes. Once maximal flexion has been attained in the CPM machine, the patient can perform heel slide exercises with the leg out of the CPM machine. Patients must achieve full hyperextension and flexion of more than 100° to 110° before hospital discharge.
Leg-control exercise is started on the day of surgery and consists of quadriceps contraction exercises and independent straight-leg raises. Weight bearing is allowed as tolerated (for bathroom privileges), but patients are instructed to restrict walking. Crutches may be used for the first few days to facilitate a normal gait pattern.
The goals for the remainder of phase 2 are the same as during the immediate postoperative period: Control swelling, maintain hyperextension, increase knee flexion to at least 110°, and establish good leg control. Progress toward these goals is evaluated 1 week after surgery at the first postoperative visit.
Phase 3: Concentrated Rehabilitation
Rehabilitation goals during postsurgical weeks 1 to 4 are to maintain full hyperextension, normalize gait, control swelling, increase flexion to at least 130°, and progress toward strengthening and participation in sport-specific activities. Heel-prop and prone-hang exercises are still practiced regularly. If tightness in hyperextension is noted, a hyperextension device is used in the clinic and at home. Heel slides and towel-pull exercises replace the CPM machine for increasing flexion.
To facilitate leg control and strength, a physical therapist teaches proper gait, stair climbing, and stair descending techniques. Near the end of phase 3, as flexion increases, specific quadriceps muscle strengthening begins with the use of a stationary bike, stair-climbing machine, and leg-press exercises. Strengthening may continue as long as the patient does not have setbacks with range of motion or swelling. If flexion decreases or swelling is noted, strengthening exercises are reduced until tightness or swelling resolves. Quadriceps muscle strength is measured with an isokinetic testing device, and the goal for the end of phase 3 is 65% of the preoperative strength of the normal leg.
As strength returns and swelling subsides, individual sport-specific activities may gradually begin (eg, free throws, dribbling, and throwing). The anticipated time for patients to reach this goal is about 3 to 5 weeks postoperatively. The specific activities are tailored to enhance patients' agility and proprioception in the desired sport.
Phase 4: Sport-Specific Activities
The goal of rehabilitation during phase 4 is to return patients to their desired activity levels in a time frame that matches their goals. Full knee hyperextension should be maintained and, ideally, flexion should be full so that patients can comfortably sit on their heels. Strengthening exercises are also done to stimulate healing and regrowth of the patellar tendon donor site.
Quadriceps muscle strength should increase to at least 85% of the noninjured knee by 4 months postoperatively. Sport-specific activities are continued and advanced as tolerated; however, if swelling occurs or range of motion decreases, activity is curtailed until it can be done without causing these motion or swelling symptoms.
Sport-specific activities begin with controlled opponent situations, such as one-on-one practice drills where the opponents do not initiate contact and understand that the purpose of the drills is to facilitate proprioception in the recovering athlete. The athlete progresses to uncontrolled practice situations, and then competition. Patients need to understand that the ability to play at the preinjury level usually requires 2 months of regular competition. Patients can expect to complete phase 4 and return to preinjury activity levels 4 to 6 months after ACL reconstruction (6).
Getting Stronger, Faster
Accelerated rehabilitation for ACL reconstruction has evolved gradually. Initially, rehabilitation was slowed because of fear of graft rupture or stretching. Years of experience have decreased these fears (6,11,12). An accelerated rehabilitation program is now believed to be safe and desirable for predictable return to full physical activity. The program follows the patient's return-to-activity goals without compromising the goals of ACL surgery.
Dr Arnold is a sports medicine-family practice physician and Dr Shelbourne is an orthopedic surgeon at Methodist Sports Medicine Center in Indianapolis. Address correspondence to K. Donald Shelbourne, MD, 1815 N Capitol Ave, Suite 530, Indianapolis, IN 46202.