Abstract
Background: Congenital absence of the cruciate ligaments is a commonly associated pathology of the knee joint in congenital longitudinal deformities. We performed a radiological analysis and investigated gait patterns in patients with congenital absence of one or both cruciate ligaments.
Patients and Methods: Thirty-four knee joints in thirty-one patients with congenital longitudinal deficiency of the lower limb were evaluated. The cruciate ligaments and associated abnormalities of the bony configuration were evaluated on magnetic resonance imaging and tunnel view radiographs. A radiological classification is proposed. Gait analysis was employed to determine kinematic, kinetic and electromyographic data in 24 of these patients and the results were compared to an age-matched control group.
Results: We differentiated 3 main types of absence of the cruciate ligaments with typical associated changes in the femoral intercondylar notch (FIN) and the tibial eminence (TE). In type I (n=19) partial closure of the FIN and hypoplasia of the TE was observed in hypoplasia or absence of the ACL, in type II (n=7) these findings were aggravated by additional underlying hypoplasia of the PCL and in type III (n=8) absence of the FIN and a flat TE was observed in aplasia of both cruciate ligaments. The main findings in gait analysis were significantly increased flexion moment of the hip, increased flexion of the knee in midstance phase and reduced ankle power in comparison to the control group.
Conclusion: The knee joint with aplastic cruciate ligaments shows typical radiological changes, thus, one will be able to distinguish between aplasia of the ACL only or both cruciate ligaments by observing plain tunnel view radiographs. Our obtained data of the gait analysis revealed specific gait patterns as adaption to underlying aplasia of the cruciate ligaments.
Theses abstracts were prepared by Professor Roger Lemaire. Correspondence should be addressed to EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.