TY - JOUR
T1 - Limb symmetry indexes can overestimate knee function after anterior cruciate ligament injury
AU - Wellsandt, Elizabeth
AU - Failla, Mathew J.
AU - Snyder-Mackler, Lynn
N1 - Publisher Copyright:
© 2017 Journal of Orthopaedic & Sports Physical Therapy®.
PY - 2017/5
Y1 - 2017/5
N2 - STUDY DESIGN: Prospective cohort. BACKGROUND: The high risk of second anterior cruciate ligament (ACL) injuries after return to sport highlights the importance of return-to-sport decision making. Objective return-to-sport criteria frequently use limb symmetry indexes (LSIs) to quantify quadriceps strength and hop scores. Whether using the uninvolved limb in LSIs is optimal is unknown. OBJECTIVES: To evaluate the uninvolved limb as a reference standard for LSIs utilized in returnto- sport testing and its relationship with second ACL injury rates. METHODS: Seventy athletes completed quadriceps strength and 4 single-leg hop tests before anterior cruciate ligament reconstruction (ACLR) and 6 months after ACLR. Limb symmetry indexes for each test compared involved-limb measures at 6 months to uninvolved-limb measures at 6 months. Estimated preinjury capacity (EPIC) levels for each test compared involved-limb measures at 6 months to uninvolved-limb measures before ACLR. Second ACL injuries were tracked for a minimum follow-up of 2 years after ACLR. RESULTS: Forty (57.1%) patients achieved 90% LSIs for quadriceps strength and all hop tests. Only 20 (28.6%) patients met 90% EPIC levels (comparing the involved limb at 6 months after ACLR to the uninvolved limb before ACLR) for quadriceps strength and all hop tests. Twenty-four (34.3%) patients who achieved 90% LSIs for all measures 6 months after ACLR did not achieve 90% EPIC levels for all measures. Estimated preinjury capacity levels were more sensitive than LSIs in predicting second ACL injuries (LSIs, 0.273; 95% confidence interval [CI]: 0.010, 0.566 and EPIC, 0.818; 95% CI: 0.523, 0.949). CONCLUSION: Limb symmetry indexes frequently overestimate knee function after ACLR and may be related to second ACL injury risk. These findings raise concern about whether the variable ACL return-to-sport criteria utilized in current clinical practice are stringent enough to achieve safe and successful return to sport.
AB - STUDY DESIGN: Prospective cohort. BACKGROUND: The high risk of second anterior cruciate ligament (ACL) injuries after return to sport highlights the importance of return-to-sport decision making. Objective return-to-sport criteria frequently use limb symmetry indexes (LSIs) to quantify quadriceps strength and hop scores. Whether using the uninvolved limb in LSIs is optimal is unknown. OBJECTIVES: To evaluate the uninvolved limb as a reference standard for LSIs utilized in returnto- sport testing and its relationship with second ACL injury rates. METHODS: Seventy athletes completed quadriceps strength and 4 single-leg hop tests before anterior cruciate ligament reconstruction (ACLR) and 6 months after ACLR. Limb symmetry indexes for each test compared involved-limb measures at 6 months to uninvolved-limb measures at 6 months. Estimated preinjury capacity (EPIC) levels for each test compared involved-limb measures at 6 months to uninvolved-limb measures before ACLR. Second ACL injuries were tracked for a minimum follow-up of 2 years after ACLR. RESULTS: Forty (57.1%) patients achieved 90% LSIs for quadriceps strength and all hop tests. Only 20 (28.6%) patients met 90% EPIC levels (comparing the involved limb at 6 months after ACLR to the uninvolved limb before ACLR) for quadriceps strength and all hop tests. Twenty-four (34.3%) patients who achieved 90% LSIs for all measures 6 months after ACLR did not achieve 90% EPIC levels for all measures. Estimated preinjury capacity levels were more sensitive than LSIs in predicting second ACL injuries (LSIs, 0.273; 95% confidence interval [CI]: 0.010, 0.566 and EPIC, 0.818; 95% CI: 0.523, 0.949). CONCLUSION: Limb symmetry indexes frequently overestimate knee function after ACLR and may be related to second ACL injury risk. These findings raise concern about whether the variable ACL return-to-sport criteria utilized in current clinical practice are stringent enough to achieve safe and successful return to sport.
KW - ACL
KW - Anterior cruciate ligament
KW - Rehabilitation
KW - Return to sport
KW - Symmetry
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U2 - 10.2519/jospt.2017.7285
DO - 10.2519/jospt.2017.7285
M3 - Review article
C2 - 28355978
AN - SCOPUS:85018972997
VL - 47
SP - 334
EP - 338
JO - Journal of Orthopaedic and Sports Physical Therapy
JF - Journal of Orthopaedic and Sports Physical Therapy
SN - 0190-6011
IS - 5
ER -