The effect of medial meniscectomy on anterior-posterior motion of the knee.

TLDR

An in vitro knee‑testing apparatus measured tibial anterior‑posterior displacement and rotation under applied forces in intact knees, after medial meniscectomy, after isolated ACL section, and after combined meniscectomy and ACL section. Meniscectomy alone did not alter tibial anterior‑posterior displacement or rotation, whereas ACL section increased anterior displacement, eliminated coupled internal rotation, and when combined with meniscectomy produced a further significant increase in anterior displacement.

Abstract

We used an in vitro knee-testing apparatus to measure anterior-posterior displacement of the tibia on the femur and the accompanying tibial rotation in response to an applied anterior-posterior force. Testing was performed on nine intact knees, on five knees after medial meniscectomy, on three knees after isolated section of the anterior cruciate ligament, and on eight knees after both excision of the medial meniscus and section of the anterior cruciate ligament. The induced anterior-posterior displacement and the coupled rotation were unaffected by meniscectomy. Isolated section of the anterior cruciate ligament allowed a significant (p less than 0.05) increase in anterior displacement but had no effect on posterior displacement. The coupled internal rotation associated with anterior displacement was lost after section of the anterior cruciate ligament. Excision of the medial meniscus and section of the anterior cruciate ligament allowed significantly (p less than 0.05) greater increases in anterior displacement than those already increased by isolated section of the anterior cruciate ligament.