Abnormal lower limb symmetry determined by function hop tests after anterior cruciate ligament rupture

TLDR

The study aimed to determine alterations in lower limb function in ACL‑deficient knees. The authors evaluated four one‑legged hop tests for sensitivity and performed regression analyses linking limb symmetry to muscle strength, symptoms, and self‑assessed function. Among 67 patients, 50 % had abnormal symmetry on a single hop and 62 % on two hops; the tests showed low sensitivity but high specificity, enabling confirmation of deficits, and abnormal symmetry correlated with reduced quadriceps isokinetic performance.

Abstract

This study assessed the sensitivity of four different types of one-legged hop tests. The goal was to deter mine alterations in lower limb function in ACL deficient knees. Regression analyses were conducted between limb symmetry as measured by the hop tests and muscle strength, symptoms, and self-assessed func tion. In 67 patients, 50% had abnormal limb symmetry scores on a single hop test. When the results of two hop tests were calculated, the percent of abnormal scores increased to 62%. The percentage of normal scores indicated that these hop tests had a low sensi tivity rate. However, the high specificity and low false- positive rates allow the tests to be used to confirm suspected defects in lower limb function. Statistical trends were noted between abnormal limb symmetry on the hop tests and low velocity quadriceps isokinetic test results.