Static and dynamic postural control in competitive athletes after anterior cruciate ligament reconstruction and controls.

PURPOSE: To evaluate the test-retest reliability and compare the static and dynamic postural control values in competitive athletes following anterior cruciate ligament (ACL) reconstruction and controls.

METHODS: Thirty athletes, 8.4 ± 1.8 months after ACL reconstruction, and thirty healthy matched controls were asked to execute single-leg stance and single-legged drop jump tests onto a force plate. Amplitude and velocity in anteroposterior and mediolateral directions, and mean total velocity were measured for static evaluation. Peak vertical ground reaction force (PVGRF) during landing and takeoff and loading rate were measured for dynamic evaluation. To evaluate test-retest reliability, 15 participants of each group repeated the tests 6-8 days after the first session. Mixed model of analysis of variance was used to determine differences between the involved, uninvolved, and control limbs. The test-retest reliability was measured using intraclass correlation coefficient and standard error of measurement.

RESULTS: Greater postural sway has been observed in the operated leg of ACL-reconstructed athletes compared with the non-operated side (P < 0.01) and the matched limb of the control group (P < 0.01). During landing, PVGRF and loading rate on the uninvolved limb of the athletes who had undergone ACL reconstruction were greater in comparison with those of the control group (P < 0.001). Both static and dynamic postural measures have high test-retest reliability, ranging from 0.73 to 0.88.

CONCLUSIONS: Static and dynamic postural measures are reliable tests to evaluate functional performance of athletes following ACL reconstruction. Eight months postsurgery, competitive athletes still demonstrated postural asymmetries, compared to matched controls, which might result in their susceptibility to future ACL injury.

LEVEL OF EVIDENCE: Prognostic study, case-control, Level III.