Altered lower extremity biomechanics following anterior cruciate ligament reconstruction during single-leg and double-leg stop-jump tasks: A bilateral total support moment analysis

• Published in: Clinical biomechanics (Bristol) 2022-01, Vol.91, p.105533-105533, Article 105533
• Main Authors: Ma, Willa, Pan, Cindy Y., Diehl, Lee H., Wittstein, Jocelyn R., Riboh, Jonathan C., Toth, Alison P., Amendola, Annunziato, Faherty, Mallory S., Killelea, Carolyn, Le, Daniel T., Sell, Timothy C.
• Format: Article
• Language: English
• Subjects: ACL reconstruction; Ankle; Hip; Knee; Total support moment
• ISSN: 0268-0033; 1879-1271
• DOI: 10.1016/j.clinbiomech.2021.105533

Injury to the anterior cruciate ligament (ACL) can lead to long-lasting biomechanical alterations that put individuals at risk of a second ACL injury. Examining the total support moment may reveal between- and within-limb compensatory strategies. Twenty-six participants who were cleared to return to sport following ACL reconstruction were recruited. Each participant completed the single-leg and double-leg stop jump tasks. These tasks were analyzed using force plates and a 3D motion analysis system. The total support moment was calculated by summing the internal moments of the hip, knee and ankle at peak vertical ground reaction force. Internal knee extensor moment was lower in the involved limb compared to the uninvolved for both tasks (17.6%, P = 0.022; 18.4%, P = 0.008). No significant between-limb differences were found for the total support moment. The involved limb exhibited an 18.2% decrease in knee joint contribution (P = 0.01) and a 21.6% increase in ankle joint contribution (P = 0.016) to the total support moment compared to the uninvolved limb in the single-leg stop jump task. Compensation for the involved knee is likely due to altered biomechanics that redistributes load to the uninvolved knee or to adjacent joints of the same limb. A partial shift in joint contribution from the knee to the ankle during the single-leg stop jump task demonstrates a tendency to decrease load to the knee. Further studies are needed to investigate how these adaptations impact the prevalence of subsequent injury and poor joint health. •Total support moment was investigated following anterior cruciate ligament reconstruction.•Total support moment was examined at peak vertical ground reaction force during the stop jump task.•Total support moment did not differ between limbs.•There was a decreased knee contribution to the total support moment in the reconstructed limb.•During the single-leg stop jump, the knee contribution partially shifted to the ankle joint.