Allograft Reconstruction of the Lisfranc Ligament.

UNLABELLED: For Lisfranc injuries, screw fixation of the medial and middle columns is currently the standard of treatment. The purpose of this study was to biomechanically evaluate the use of allograft for a severed Lisfranc ligament compared to standard screw fixation and the intact condition. Six pairs of fresh-frozen cadaveric lower extremities were prepared with reflective marker arrays and cyclically loaded to simulate partial weight bearing under 4 sequential testing conditions: (1) intact ligament, (2) disrupted ligament, (3) tendon allograft reconstructed ligament, and (4) rigid screw fixation. The relative displacement between the medial cuneiform and the second metatarsal was assessed via motion analysis. A mixed model analysis of variance was used to determine the significance (α = .05) of displacement differences. Mean displacements and 95% confidence intervals for each condition were as follows: (1) intact 9.1 (7.1-11.2) mm, (2) cut ligament 9.4 (7.4-11.5) mm, (3) allograft fixation 8.8 (6.8-10.9) mm, and (4) screw fixation 8.2 (6.2-10.3) mm. There were no significant differences among the specimens according to condition. Allograft fixation provided adequate strength and stability and did not differ significantly compared to intact or screw fixation.

LEVELS OF EVIDENCE: Level V: Bench testing.