The clinical effects of different repair methods on the biomechanical stability of ankle ligament injuries

摘要

Objective: To explore the effects of different repair methods on the biomechanical stability of patients with ankle ligament injuries. Methods: Normal ankle specimens from 24 adult cadavers were randomly divided into groups A, B, C, D, E, and F, with 4 in each group. Group A was not given any treatment. Group B was established as a distal tibiofibular syndesmosis ligament fracture model, while group C was established as a medial and lateral ligaments and distal tibiofibular syndesmosis ligament fracture model. The models in groups D, E, and F were all established in the same way as group C, but group D had repaired medial and lateral ligaments, group E had repaired lateral ligaments and distal tibiofibular syndesmosis ligaments, and group F had repaired medial and lateral ligaments and distal tibiofibular syndesmosis ligaments. A biomechanical tester was applied to analyze the influence of the ligament injuries and repair methods on the stress areas and ankle joint surfaces. Biomechanical data in dorsiflexion 20 degrees, eversion 5 degrees, internal rotation 20 degrees, plantar flexion 30 degrees, external rotation 20 degrees, and in a neutral position were measured respectively. Results: When the ankle joint was in dorsiflexion 20 degrees, eversion 5 degrees, internal rotation 20 degrees, plantar flexion 30 degrees, external rotation 20 degrees, and in a neutral position, group A showed significantly higher stress areas than the groups B and C (both P<0.05), and group F showed significantly higher stress areas than groups D and E (both P<0.05). The stress force in group A was significantly lower than it was in groups B and C (both P<0.05), and the stress force in group F was significantly lower than it was in groups D and E (both P<0.05). There were no significant differences between groups A and F (P>0.05). Under loading pressures of 100 N, 200 N, 300 N, 400 N, 500 N, and 600 N, the vertical displacement of the tibiotalar joint in group A was significantly lower than it was in groups B and C (both P<0.05), and the vertical displacement of the tibiotalar joint in group F was significantly lower than it was in groups D and E (both P<0.05). There were no significant differences between groups A and F (P>0.05). Conclusion: Any injury of the medial, lateral, or distal tibiofibular syndesmosis ligaments has an effect on ankle joint stability. Also, a syndesmosis ligament injury can aggravate ankle joint instability, resulting in a reduction of joint stress area and an increase in stress. Repairing all the ligaments is the best way to improve the biomechanical stability of the ankle joint when the three ligaments are fractured jointly.