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Rehabilitation for Anterior Cruciate Ligament Injury Treatment & Management

  • Author: Tarek O Souryal, MD; Chief Editor: Consuelo T Lorenzo, MD  more...
Updated: Mar 01, 2016

Rehabilitation Program

Physical Therapy

The primary goals in the treatment of anterior cruciate ligament (ACL) rupture are restoration of function in the short term and the prevention of long-term pathologic changes in the knee. Nonoperative treatment is a reasonable approach in patients who are not athletically active.

Research has demonstrated that the natural history of untreated complete injuries of the ACL consists of the progression of symptomatic instability to recurrent injuries. These injuries damage the menisci and the articular cartilage, eventually leading to osteoarthritis and osteoarthrosis.[13]

The key to successful treatment of an anterior cruciate ligament (ACL) tear is proper and early rehabilitation. Preoperative and postoperative rehabilitation programs are similar initially. Swelling control and restoration of motion and strength are the goals of each.

The postoperative rehabilitation program begins as soon as the patient awakens from anesthesia, especially because patients are discharged earlier now than they were in previous years. Quadriceps co-contractions make up the first exercise that patients should be taught for the maintenance of terminal extension.

Passive motion is emphasized with active flexion and assisted extension in the sitting or prone position to ensure good leg control (ie, ability to flex the hip and lift the leg against gravity without assistance.) A continuous passive motion machine (CPM) can be used to establish 0-30° of motion immediately postoperatively and to progress to 60° of knee flexion by the morning following the operation. The patient then begins gait training with crutches (weight bearing as tolerated), with the knee in an immobilizer. The patient usually can be discharged on the first postoperative day and should be encouraged to avoid crowds, keep the leg elevated when not ambulating, use the crutches at all times for protection, and continue frequent icing.

A number of different programs are used by different physical therapists. The therapy program chosen depends on the activity level of the patient and the type of surgery performed, coexistent injuries (meniscal or other ligamentous injury), the surgeon, the insurance policy, and time constraints.

Goal-oriented rehabilitation for patellar tendon grafts

The following rehabilitation program is an accelerated program for patellar tendon grafts. Note that the other grafts rehabilitate slightly differently. This rehabilitation program is classified as a goal-oriented approach. The dates listed are not meant to be followed strictly and can be varied by a day or 2, depending on the physician or the patient's schedule.

On day 3 following surgery, have the patient return to the surgeon for evaluation. Begin therapy on an outpatient basis, concentrating on gait training and other ambulation-oriented activities. The goal is to maintain terminal knee extension and progression toward 90° of flexion. The therapist emphasizes a normal heel-to-toe gait pattern, and the patient may weight bear as tolerated on the involved leg. Continue passive flexion ROM exercises. Have the patient increase quadriceps activity, introducing the partial squat with progression from bilateral to unilateral, placing increased body weight on the extremity involved at no more than 45° of flexion. Continue these exercises for 1 week. Continue the knee immobilizer when ambulating and continue regular icing of the knee.

On day 10 following surgery, have the patient return to the surgeon for evaluation. Advance therapy to include wall slide-squats and a stationary bike as tolerated. Place emphasis on terminal extension, progressive flexion, and full weight-bearing ambulation with normal heel-to-toe mechanics. In a controlled environment (no pets, children, or distractions), have the patient begin practicing crutch ambulation while out of the knee immobilizer. The patient should achieve full terminal knee extension and approximately 90-100° of knee flexion.

Three to 4 weeks after the surgery, the aggressive patient is ambulating with normal gait mechanics. At this point, the knee immobilizer can be removed. Advance the patient's activity to include loaded squats, swimming, eccentric quadriceps strengthening, bridging with a physioball, and a stair stepper. During this time, if the therapist is not observant, the patient can develop tendonitis of the quadriceps tendon or other repetitive use injuries of the lower extremity. Application of ice after each therapy session is very important.

Six weeks after surgery, release the patient to light jogging or bicycling. If the patient is older and has concomitant degenerative joint disease, encourage bicycling. The graft is still very weak at this stage, so advise the patient that it is important not to fall. The patient should jog only on a track or other flat protected surface. At this point, active ROM should be approaching 0-125° with minimal or no joint effusion. Work on balance and proprioception with activity drills.

At 3 months, recommend that the patient begin a gradual return to normal activities. At this point, most people do not require bracing, but occasionally, some athletes request a brace to increase their own comfort level when competing.

Open kinetic chain (OKC) and closed kinetic chain (CKC) exercises

Significant discussion surrounds the difference between OKC and CKC exercises during ACL rehabilitation. The difference concerns the assumption that CKC exercises are safer than OKC exercises because they place less strain on the ACL graft, producing less patellofemoral pain. The second assumption is that CKC exercises are more functional and are equally effective in improving quadriceps muscle force production.

A study by Beynnon and colleagues showed no difference in ACL strain characteristics between OKC and CKC exercises.[14, 15] A report by Fleming and coauthors argues that, with improved anatomical placement of the ACL graft, the graft may respond more like the intact ACL during OKC and CKC exercises. Therefore, these 2 articles argue that both types of exercise can be performed safely.

With regard to safety, OKC and CKC exercises can be applied in a manner that minimizes the risk of excessive graft strain and patellofemoral compression. Using different knee joint motion excursions for each type of exercise is the key to risk reduction. When OKC knee extensions are performed, limit knee joint motion to more flexed positions. During CKC lower extremity exercises, limit knee joint motions to more extended positions.

Nonoperative treatment

Patients may for a variety of reasons—if, for example, they are not highly active or athletic or are minimally symptomatic—opt for nonoperative treatment. In these cases, after initial control of pain and effusion, start hamstring and quadriceps activation/disinhibition and protected weight bearing in a hinged brace. As swelling and pain slowly resolve, ROM should return to normal, or nearly normal, parameters. Start exercises that take place in an anterior/posterior plane (eg, stationary cycling). Exercises need to be nonballistic.


Surgical Intervention

Several options exist for the patient who elects to have surgery. For complete rupture, no local healing response is detectable at the injury site, and a graft must be used to replace the ACL.[16] Today, 4 options are used. The first 3 types are autografts using the central one third of the patellar ligament (considered a bone-ligament-bone graft), the quadruple semitendinosus/gracilis tendon, or the quadriceps tendon.[17, 18] The fourth type of graft is a cadaveric allograft.


The patellar ligament with its bony ends has been a popular ACL replacement because of its high ultimate tensile load (~2300 N), its stiffness (~620 N/mm), and the possibility for rigid fixation with its attached bone graft.

By comparison, the dimensions of a round, 10-mm quadruple semitendinosus/gracilis tendon graft (hamstring graft) are more comparable to those of the intact ACL, and its ultimate tensile load has been reported to be as high as 4108 N. The quadruple tendon graft also may provide a multiple bundle replacement graft that better approximates the function of the 2-bundle ACL. Disadvantages of this soft-tissue graft include concern over tendon healing within the osseous tunnels and a lack of rigid bony fixation. A 1998 study from Japan suggests that aggressive early rehabilitation after an ACL reconstruction using the hamstring graft has more risk for residual laxity than does the patellar tendon graft.[19]

The quadriceps tendon graft has been shown to have an ultimate tensile load of as high as 2352 N. This graft has become an alternative replacement graft, especially for revision ACL surgeries and for patients with multiple ligament injuries in the knee.

Cadaver studies have shown that the strength of fixation between the patellar tendon graft and the hamstring graft is equal to approximately 450 N, but the patellar graft can achieve fixation strength of as high as 1000 N. Grafts fixed to bone close to the articular surface (ie, patellar tendon grafts) undergo less strain and are stiffer than are those grafts fixed outside of drill holes (ie, hamstring grafts).


Allograft tissues are harvested from human donors and typically include either the patellar tendon or the Achilles tendon.

Allografts are used for multiple ligament reconstructions and revisions of ligament reconstructions, as well as for the treatment of patients who are not high-performance athletes. However, the reduction of tensile strength that occurs with sterilization is a concern, as is the risk of inflammatory reactions.

Choice of graft type

In a prospective comparative 9-year follow-up study by Wipfler et al, the authors review the innovative technique of implant-free press-fit ACL reconstruction with bone–patellar tendon or quadrupled hamstring tendon grafts. This technique saves the cartilage and meniscal status of the knee, leaving little long-term differences between the operated and nonoperated knee. No significant differences, between the two groups, were found with range of motion, pivot-shift test, or quadriceps strength. Anterior knee pain was considerably less when kneeling and knee walking for those who underwent quadrupled hamstring tendon grafts, but hamstring strength was decreased.[20]

Ultimately, the decision as to which graft is best is still a matter of contention. The agreement is that the patellar and hamstring grafts are superior to the quadriceps graft and the allograft; however, the decision as to which is the better of the patellar and hamstring grafts depends on which surgeon is operating.

With regard to osteoarthritis, hamstring grafts have shown a lower rate of radiological osteoarthritis than patellar grafts at 15 years postsurgery.[21] In spite of the type of graft, some patients will develop osteoarthritis in the reconstructed knee, especially patients with concomitant or subsequent meniscectomy.


A prospective study by Müller et al indicated that results from the single-hop test for distance and the Anterior Cruciate Ligament-Return to Sport After Injury Scale (ACL-RSI) are significant factors in predicting whether an athlete will return to a preinjury level of sport after ACL reconstruction.[22]

In the study, 40 patients who underwent semitendinosus tendon autograft for an ACL rupture were assessed 6 months postoperatively with a variety of tools—including four single-leg hop tests, the ACL-RSI, the 2000 International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, the Tampa Scale of Kinesiphobia-11 (TSK-11), and evaluation of knee extensor and flexor strength—to determine which of these could most effectively predict whether a patient was likely to return to his/her preinjury level of sport. Patients were then interviewed at 7 months postoperatively to identify which of them could be classified as “return to sport” (RS) or “non-return to sport” (nRS).[22]

The investigators found that the single-hop-for-distance limb symmetry index value, with a cutoff point of 75.4%, and the ACL-RSI, with a cutoff point of 51.3 points, had sensitivities of 0.74 and 0.97, respectively, and specificities of 0.88 and 0.63, respectively, for predicting which patients would fall into the RS or nRS group.[22]

A study by Villa et al found that the following factors had a positive influence on recovery in patients following ACL reconstruction: age younger than 20 years, a higher preinjury Tegner activity scale score, professional-level sports practice, an absence of concurrent capsular lesions and of postoperative knee bracing, a higher percentage of on-field rehabilitation sessions during patients’ customized rehabilitation protocol, and a deficit in knee flexor and extensor strength of less than 20% at the first isokinetic knee test.[23]



In anterior cruciate ligament injury cases, presurgical consultations with other services generally are needed only in connection with surgical clearance. After surgery, it is important to consult with a specialist in physical medicine and rehabilitation (PMR) for initiation of a program to facilitate the patient's rehabilitation.


Other Treatment

Some patients, especially those who are minimally involved in sports, elect not to have surgery and instead choose bracing. Several custom and off-the-shelf, anterior cruciate ligament–specific braces are available. For patients who are involved in vigorous sports, the use of braces without surgical stabilization is not recommended.

Contributor Information and Disclosures

Tarek O Souryal, MD Head Team Physician, Dallas Mavericks; Director, Texas Sports Medicine and Orthopaedic Group; Staff, Department of Orthopaedic Surgery, Presbyterian Hospital of Dallas; Clinical Professor, Departments of Orthopedic Surgery and Physical Medicine and Rehabilitation, University of Texas Southwestern Medical Center

Tarek O Souryal, MD is a member of the following medical societies: American Academy of Orthopaedic Surgeons

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Michael T Andary, MD, MS Professor, Residency Program Director, Department of Physical Medicine and Rehabilitation, Michigan State University College of Osteopathic Medicine

Michael T Andary, MD, MS is a member of the following medical societies: American Academy of Physical Medicine and Rehabilitation, American Association of Neuromuscular and Electrodiagnostic Medicine, American Medical Association, Association of Academic Physiatrists

Disclosure: Received honoraria from Allergan for speaking and teaching.

Chief Editor

Consuelo T Lorenzo, MD Medical Director, Senior Products, Central North Region, Humana, Inc

Consuelo T Lorenzo, MD is a member of the following medical societies: American Academy of Physical Medicine and Rehabilitation

Disclosure: Nothing to disclose.

Additional Contributors

Robert E Windsor, MD, FAAPMR, FAAEM, FAAPM President and Director, Georgia Pain Physicians, PC; Clinical Associate Professor, Department of Physical Medicine and Rehabilitation, Emory University School of Medicine

Robert E Windsor, MD, FAAPMR, FAAEM, FAAPM is a member of the following medical societies: American Academy of Pain Medicine, American Academy of Physical Medicine and Rehabilitation, American College of Sports Medicine, American Medical Association, International Association for the Study of Pain, Texas Medical Association

Disclosure: Nothing to disclose.


Kenneth Adams, MD Assistant Professor, Department of Physical Medicine and Rehabilitation, University of Texas Southwestern Medical School

Kenneth Adams, MD is a member of the following medical societies: American Academy of Physical Medicine and Rehabilitation, American Medical Association, and Texas Medical Association

Disclosure: Nothing to disclose.

  1. Sanders TL, Maradit Kremers H, Bryan AJ, et al. Incidence of Anterior Cruciate Ligament Tears and Reconstruction: A 21-Year Population-Based Study. Am J Sports Med. 2016 Feb 26. [Medline].

  2. Arendt E, Dick R. Knee injury patterns among men and women in collegiate basketball and soccer. NCAA data and review of literature. Am J Sports Med. 1995 Nov-Dec. 23(6):694-701. [Medline].

  3. Hutchinson MR, Ireland ML. Knee injuries in female athletes. Sports Med. 1995 Apr. 19(4):288-302. [Medline].

  4. Nagano Y, Ida H, Akai M, et al. Biomechanical characteristics of the knee joint in female athletes during tasks associated with anterior cruciate ligament injury. Knee. 2008 Dec 23. [Medline].

  5. Noyes FR, Mooar PA, Matthews DS, et al. The symptomatic anterior cruciate-deficient knee. Part I: the long-term functional disability in athletically active individuals. J Bone Joint Surg [Am]. 1983 Feb. 65(2):154-62. [Medline].

  6. Acasuso Diaz M, Collantes Estevez E, Sanchez Guijo P. Joint hyperlaxity and musculoligamentous lesions: study of a population of homogeneous age, sex and physical exertion. Br J Rheumatol. 1993 Feb. 32(2):120-2. [Medline].

  7. Kibler WB, Chandler TJ, Uhl T, et al. A musculoskeletal approach to the preparticipation physical examination. Preventing injury and improving performance. Am J Sports Med. 1989 Jul-Aug. 17(4):525-31. [Medline].

  8. Godshall RW. The predictability of athletic injuries: an eight-year study. J Sports Med. 1975 Jan-Feb. 3(1):50-4. [Medline].

  9. Jackson DW, Jarrett H, Bailey D, et al. Injury prediction in the young athlete: a preliminary report. Am J Sports Med. 1978 Jan-Feb. 6(1):6-14. [Medline].

  10. Shambaugh JP, Klein A, Herbert JH. Structural measures as predictors of injury basketball players. Med Sci Sports Exerc. 1991 May. 23(5):522-7. [Medline].

  11. Souryal TO, Moore HA, Evans JP. Bilaterality in anterior cruciate ligament injuries: associated intercondylar notch stenosis. Am J Sports Med. 1988 Sep-Oct. 16(5):449-54. [Medline].

  12. Souryal TO, Freeman TR. Intercondylar notch size and anterior cruciate ligament injuries in athletes. A prospective study [published erratum appears in Am J Sports Med 1993 Sep-Oct;21(5):723]. Am J Sports Med. 1993 Jul-Aug. 21(4):535-9. [Medline].

  13. Louboutin H, Debarge R, Richou J, et al. Osteoarthritis in patients with anterior cruciate ligament rupture: a review of risk factors. Knee. 2008 Dec 19. [Medline].

  14. Beynnon BD, Fleming BC, Johnson RJ, et al. Anterior cruciate ligament strain behavior during rehabilitation exercises in vivo. Am J Sports Med. 1995 Jan-Feb. 23(1):24-34. [Medline].

  15. Beynnon BD, Uh BS, Johnson RJ, et al. Rehabilitation after anterior cruciate ligament reconstruction: a prospective, randomized, double-blind comparison of programs administered over 2 different time intervals. Am J Sports Med. 2005 Mar. 33(3):347-59. [Medline].

  16. Barker T, Leonard SW, Trawick RH, et al. Modulation of inflammation by vitamin E and C supplementation prior to anterior cruciate ligament surgery. Free Radic Biol Med. 2008 Nov 27. [Medline].

  17. Wu C, Noorani S, Vercillo F, et al. Tension patterns of the anteromedial and posterolateral grafts in a double-bundle anterior cruciate ligament reconstruction. J Orthop Res. 2008 Dec 30. [Medline].

  18. Kim SJ, Jo SB, Kumar P, et al. Comparison of single- and double-bundle anterior cruciate ligament reconstruction using quadriceps tendon-bone autografts. Arthroscopy. 2009 Jan. 25(1):70-7. [Medline].

  19. Muneta T, Sekiya I, Ogiuchi T, et al. Effects of aggressive early rehabilitation on the outcome of anterior cruciate ligament reconstruction with multi-strand semitendinosus tendon. Int Orthop. 1998. 22(6):352-6. [Medline].

  20. Wipfler B, Donner S, Zechmann CM, Springer J, Siebold R, Paessler HH. Anterior cruciate ligament reconstruction using patellar tendon versus hamstring tendon: a prospective comparative study with 9-year follow-up. Arthroscopy. 2011 May. 27(5):653-65. [Medline].

  21. Leys T, Salmon L, Waller A, Linklater J, Pinczewski L. Clinical results and risk factors for reinjury 15 years after anterior cruciate ligament reconstruction: a prospective study of hamstring and patellar tendon grafts. Am J Sports Med. 2012 Mar. 40(3):595-605. [Medline].

  22. Müller U, Krüger-Franke M, Schmidt M, et al. Predictive parameters for return to pre-injury level of sport 6 months following anterior cruciate ligament reconstruction surgery. Knee Surg Sports Traumatol Arthrosc. 2014 Sep 2. [Medline].

  23. Villa FD, Ricci M, Perdisa F, et al. Anterior cruciate ligament reconstruction and rehabilitation: predictors of functional outcome. Joints. 2015 Oct-Dec. 3 (4):179-85. [Medline]. [Full Text].

  24. Hewett TE, Lindenfeld TN, Riccobene JV, et al. The effect of neuromuscular training on the incidence of knee injury in female athletes. A prospective study. Am J Sports Med. 1999 Nov-Dec. 27(6):699-706. [Medline].

  25. Wojtys EM, Huston LJ, Taylor PD, et al. Neuromuscular adaptations in isokinetic, isotonic, and agility training programs. Am J Sports Med. 1996 Mar-Apr. 24(2):187-92. [Medline].

  26. Biedert RM, Bachmann M. [Women's soccer. Injuries, risks, and prevention]. Orthopade. 2005 May. 34(5):448-53. [Medline].

  27. Myklebust G, Bahr R. Return to play guidelines after anterior cruciate ligament surgery. Br J Sports Med. 2005 Mar. 39(3):127-31. [Medline]. [Full Text].

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