Anterior Cruciate Ligament (ACL) Reconstruction Return to Sport Guidelines

Background Information

- An ACL injury is the most common athletic knee injury, with about 250,000 individuals

suffering from an ACL rupture each year in the United States alone. (see notes 1 & 2)

- Females are more likely to suffer this injury than males due to females being more quad

dominant during landing and stop-jumping activities, as well as tending to land in a

collapsing pattern that causes increased genu valgum (knock-knees). (see note 3)

- Surgical reconstruction of the ACL is usually performed about 3-6 weeks after the injury

occurs to allow time for inflammation to subside and full range of motion of the knee

(flexion and extension) to be restored. (see note 3)

- Graft types used during reconstruction include autografts (tissue taken from another part

of the patient’s body) and allografts (tissue harvested from a cadaver). The most

commonly used grafts include bone-patellar tendon-bone autograft, hamstring tendon

autograft, or quadriceps tendon autograft. (see notes 4 & 5)

Research (see notes 1 & 2)

- Research has shown that rehabilitation performed before having surgery has been

associated with better outcomes post-surgery. Additionally, return to sport (RTS) is not

recommended until 9-12 months after surgery. It has been found that the re-injury rate

was reduced by 51% for each month return to sport was delayed until 9 month after

surgery. Another finding is that athletes who failed any of the return to sport criteria were

more likely to sustain a re-injury (38%), compared to those who passed all of the return

to sport criteria (6%). Research also shows that pivoting sport athletes (soccer,

basketball, etc.) who passed specific criteria prior to RTS have a 4-6x lower risk for re-

injury.

RTS Testing (see notes 1, 2, & 5)

- When conducting RTS testing, this should include strength testing, hop testing,

psychological readiness, and agility tests.

- For strength testing, the quadriceps are usually tested. A handheld dynamometer, such

as the MicroFET2, can be used to do so. A limb symmetry index (ratio used to compare

an affected leg to the unaffected leg) of greater than or equal to 90% is ideal. To

calculate, limb symmetry index = (Involved/Uninvolved) x 100.

- For single leg hop testing, the four most commonly used tests are the single hop for

distance, triple hop for distance, the crossover hop for distance, and a 6 meter hop for

time. A limb symmetry index of greater than or equal to 90% is the goal.

- For psychological readiness, the Knee Outcome Survey - Activities of Daily Living Scale

can be used, and a score of greater than or equal to 90 is ideal.

- For agility, the running T test could be used, with a goal for the patient to be able to

perform the test in less than 11 seconds.

Additional Things to Consider with RTS Testing (see note 5)

- It has been shown that a patient who completed 6 months of rehab incorporating

jumping and agility tasks were almost 8x more likely to RTS compared to those who did

not. Although there is a lack of research to determine when it is best to perform RTS

testing, at least 9 months after surgery is suggested. Additionally, even if the patient

passes the commonly used single-leg hop tests, additional asymmetries may be present

if medial/lateral and rotational hop tests are implemented.

Helpful Resources for ACL Reconstruction Rehabilitation

- Massachusetts General Brigham Sports Medicine Rehab Protocol for ACL

Reconstruction, which includes a Return to Running Program and an Agility and

Plyometric Program.

- Link:https://www.massgeneral.org/assets/mgh/pdf/orthopaedics/sports-

medicine/physical-therapy/rehabilitation-protocol-for-acl.pdf

- Boston Sports Medicine & Research Institute ACL Injury Overview, which also includes

rehabilitation guidelines and exercise examples.

-

Link: https://www.bostonsportsmedicine.com/pdf/protocols/acl_reconstruction__re

hab_protocol.pdf

References

1. Brinlee AW, Dickenson SB, Hunter-Giordano A, Snyder-Mackler L. ACL reconstruction

rehabilitation: clinical data, biologic healing, and criterion-based milestones to inform a

return-to-sport guideline. Sports Health. 2022;14(5):770-779.

doi:10.1177/19417381211056873

2. Filbay SR, Grindem H. Evidence-based recommendations for the management of

anterior cruciate ligament (ACL) rupture. Best Pract Res Clin Rheumatol. 2019;33(1):33-

47. doi:10.1016/j.berh.2019.01.018

3. Houglum PA. Therapeutic Exercise for Musculoskeletal Injuries, 4th edition. Champaign,

IL: Human Kinetics; 2016.

4. Paschos NK, Howell SM. Anterior cruciate ligament reconstruction: principles of

treatment. EFORT Open Rev. 2016;1(11):398-408. doi:10.1302/2058-5241.1.160032

5. Gokeler A, Dingenen B, Hewett TE. Rehabilitation and return to sport testing after

anterior cruciate ligament reconstruction: where are we in 2022? Arthrosc Sports Med

Rehabil. 2022;4(1):e77-e82. doi:10.1016/j.asmr.2021.10.025