摘要

Background: Anterior cruciate ligament (ACL) reinjury rates are high in adolescent patients. Knee braces are commonly used after ACL reconstruction to prevent reinjury during return to sports.
Hypothesis: Adolescent patients following ACL injury would demonstrate a decreased vertical ground-reaction force, knee extension moment, knee flexion angle, and knee flexion velocity on the surgical limb when compared with the nonsurgical limb during a side-cutting task. A functional knee extension-resistant brace would decrease the limb asymmetries.
Study Design: Controlled laboratory study.
Methods: Twenty-three adolescent patients 6 months after ACL reconstruction were recruited for this study. Three-dimensional kinematic and kinetic data were collected bilaterally (surgical, nonsurgical) during a 35 degrees side-cutting task while the patient was wearing and not wearing a functional knee extension-resistant brace (nonbraced, braced) on the surgical limb.
Results: The surgical limb demonstrated a significant decrease in peak impact vertical ground-reaction force (2.55 body weight [BW] vs 2.8 BW; P < .01), peak propulsion vertical ground-reaction force (2.15 BW vs 2.3 BW; P < .01), peak knee extension moment (0.13 BW x body height [BH] vs 0.17 BW x BH; P < .01), knee flexion angle at peak knee flexion velocity (27.8 degrees vs 30.0 degrees; P = .01), peak knee flexion angle (44.1 degrees vs 48.5 degrees; P < . 01), and peak knee flexion velocity (571.3 deg/sec vs 640.1 deg/sec; P < .01) when compared with the nonsurgical limb during both nonbraced and braced conditions. Bracing increased the initial knee flexion velocity (42.4 deg/sec vs 240.2 deg/sec; P = .01) and decreased the initial knee flexion angle on the surgical limb (13.1 degrees vs 15.7 degrees; P < . 01). Bracing also affected kinematics of the nonsurgical limb. Bracing did not decrease the asymmetry between surgical and nonsurgical limbs.
Conclusion: Adolescent patients 6 months after ACL reconstruction demonstrated significant kinematic and kinetic asymmetries between the surgical and nonsurgical limbs. The limb asymmetries persisted when the patients were wearing a functional knee brace. There were changes in the surgical knee kinematics with and without bracing, especially near initial ground contact.

  • 出版日期2012-12