BIOMECHANICAL CONSEQUENCES OF ANATOMICAL RECONSTRUCTION OF THE LATERAL LIGAMENTS TO THE ANKLE JOINT COMPLEX: AN IN VITRO INVESTIGATION

The three-dimensional kinematics of both the ankle and the subtalar joints was examined after cutting and subsequent repairing the lateral ligaments using three anatomical procedures: direct repair, tendon graft and carbon-fibre implant. All procedures restored the original kinematics of the subtalar joint, except the plantar/dorsiflexion. For the talocrural joint, the tendon graft and the carbon fibre implant left a minimal laxity for the inversion/eversion and internal/external rotation movements. The direct repair procedure restored the physiologic kinematics almost completely and gave the best results, allowing to restore almost completely the physiologic kinematics. Each procedure respected the insertion points and the directions of the original ligaments. However, the different results for the direct repair and the other two anatomical procedures show that this condition alone is not sufficient to restore the kinematics of the talocrural and subtalar joints perfectly. None of the procedures caused a movement restriction. Thus, we recommend the direct repair of the ligaments as the method of choice. If the quality or the conditions of the ligaments do not allow a direct repair, we recommend to use another anatomical reconstruction.