Dynamic-Position-Sense Impairment’s Independence of Perceived Knee Function in Women With ACL Reconstruction

Abstract

Context:There is conflicting evidence in the literature regarding whether women with anterior cruciate ligament reconstruction (ACLR) demonstrate impaired proprioception. This study examined dynamic-position-sense accuracy and central-nervous-system (CNS) processing time between those with and without long-term ACLR.Objective:To compare proprioception of knee movement in women with ACLR and healthy controls.Design:Cross-sectional.Setting:Human neuromuscular performance laboratory.Participants:11 women (age 22.64 ± 2.4 y) with ACLR (1.6–5.8 y postsurgery) and 20 women without (age 24.05 ± 1.4 y).Interventions:The authors evaluated subjects using 3 methods to assess position sense. During knee flexion at pseudorandomly selected speeds (40°, 60°, 80°, 90°, and 100°/s), subjects indicated with their index finger when their knee reached a predetermined target angle (50°). Accuracy was calculated as an error score. CNS processing time was computed using the time to detect movement and the minimum time of angle indication. Passive and active joint-position sense were also determined at a slow velocity (3°/s) from various knee-joint starting angles.Main Outcome Measurements:Absolute and constant error of target angle, indication accuracy, CNS processing time, and perceived function.Results:Both subject groups showed similar levels of error during dynamic-position-sense testing, despite continued differences in perceived knee function. Estimated CNS processing time was 260 ms for both groups. Joint-position sense during slow active or passive movement did not differ between cohorts.Conclusions:Control and ACLR subjects demonstrated similar dynamic, passive, and active joint-position-sense error and CNS processing speed even though ACLR subjects reported greater impairment of function. The impairment of proprioception is independent of post-ACLR perception of function.