Return to Sport After ACL Reconstruction: Strength and Functionality Testing

Area of Science:

• Orthopaedic surgery
• Sports medicine
• Rehabilitation science

Background:

• Functionality testing aids clinicians and patients in assessing readiness for return to sport (RTS) after anterior cruciate ligament (ACL) reconstruction.
• Low performance on these tests correlates with an increased risk of reinjury.
• Historically, a significant percentage of orthopedic surgeons (41% as of 2013) do not routinely use strength or functionality testing for RTS evaluations.

Purpose of the Study:

• To highlight the importance of functionality testing in the rehabilitation of ACL reconstruction patients.
• To emphasize the role of these tests in determining safe return to sport.
• To present a suite of tests used in intermediate to late-stage rehabilitation.

Main Methods:

• The study describes various functional tests including single and triple hop for distance, triple crossover hop, single and double vertical leg jumps, and drop jump landing.
• Isokinetic and isometric strength testing are also detailed.
• The Limb Symmetry Index (LSI) is presented as a reliable measure, calculated as the ratio of the involved leg's performance to the uninvolved leg's performance.

Main Results:

• Incorporating these tests into rehabilitation programs can reduce the risk of ACL reinjury by 75% to 84%.
• A Limb Symmetry Index (LSI) of 90% or greater on hop tests is a common threshold for passing.
• Patients achieving an LSI of 90% or higher on these tests demonstrate a lower likelihood of experiencing knee reinjury.

Conclusions:

• Strength and functionality tests are crucial tools for reducing reinjury risk following ACL reconstruction.
• While effective, limitations such as equipment and funding may restrict the use of certain tests (e.g., isokinetic/isometric).
• Combining functional tests with clinical evaluation and psychological assessment, alongside sport-specific testing, optimizes patient outcomes and readiness for return to sport.