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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, OBJECTIVE, METHODS, METHODS, RESULTS. Meshes: Aged, Anterior Cruciate Ligament Injuries, Humans, Joint Instability, Knee Injuries, Menisci, Tibial, Tibial Meniscus Injuries.
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Does anterior knee laxity increase gapping of posterior horn medial meniscal tears? Context: Meniscal tears often occur in association with anterior cruciate ligament (ACL) lesions or in chronically lax knees. It is also known that meniscal repairs are less likely to heal in ACL-deficient knees. To test the effect of different knee joint motion and loading conditions on the gapping behavior of longitudinal posterior horn meniscal tears in stable and ACL-deficient knee joints. Controlled laboratory study. Longitudinal tears of 3 cm were set in the posterior horn of the medial menisci in 10 human cadaveric joints. The medial plateau of the knees was replaced by a transparent replica, and an arthroscope was placed underneath to observe the gapping phenomenon of the meniscal tears. The maximum gap width occurring during flexion-extension under various motion and loading situations was registered in intact and ACL-deficient joints before and after meniscal repair with FasT-Fix suture anchors. Longitudinal meniscal tears gapped significantly wider after ACL transection under 30-N axial joint load (P < .05). Increasing the axial load to 200 N or applying external moments to the knee did not lead to further alterations in the gap size. Gapping was significantly reduced after meniscal repair (P < .01). However, after meniscal repair, gapping under 30-N and 200-N axial joint load was still increased significantly after ACL transection compared with the ACL-intact state (P < .05).
assistant
Anterior knee laxity increases gapping across both unrepaired and repaired vertical peripheral medial meniscal posterior horn tears. Final Decision: yes