[BIOMECHANICAL STUDY ON Lisfranc LIGAMENT RECONSTRUCTION WITH AUTOGENOUS TENDON]

To explore the feasibility of Lisfranc ligament reconstruction with autogenous tendon through biomechanical testing.

Twelve fresh-frozen cadaveric lower limbs were prepared three sequential testing conditions: intact Lisfranc ligament (intact group), disrupted Lisfranc ligament (disrupted group), and Lisfranc ligament reconstruction (reconstruction group). Under fixing on the Bose mechanical test machine, three models were given 0-600 N axial loading in the neutral position and the plantar flexion of 30 degrees according to the speed of 10 N/s, every 100 N load with a 1-minute interval. The medial cuneiform (C1) and the second metatarsal (M2) base displacement and the foot transverse arch height were recorded under different loads.

In the neutral position and the plantar flexion of 30 degrees, C1-M2 displacement and foot transverse arch height showed an increasing trend with increased load under 0-600 N axial loading. There were significant differences in C1-M2 displacement variation in 2 positions among groups (P < 0.05). In disrupted group, the C1-M2 displacement variation in neutral position was significantly lower than that in plantar flexion of 30 degrees (t = 7.392, P = 0.000). In the neutral position, the foot transverse arch height variation in the disrupted group and the reconstruction group was significantly higher than that in the intact group (P < 0.05), but there was no significant difference between the disrupted group and reconstruction group (P > 0.05).

Lisfranc ligament reconstruction with autogenous tendon can reduce the C1-M2 displacement variation and stabilize Lisfranc joint to a certain degree. Reconstruction of both dorsal ligament and Lisfranc ligament will not improve the buffering capacity. The C1-M2 displacement variation in the plantar flexion of 30 degrees is more obvious than that in neutral position, so it is helpful to improve clinical diagnosis of occult Lisfranc damage.