Clinical and magnetic resonance imaging assessment of anatomical lateral ankle ligament reconstruction: comparison of tendon allograft and autograft.

PURPOSE

To compare the results of anatomical lateral ankle ligament (LAL) reconstruction with tendon allograft and autograft using clinical scores and ultrashort echo time (UTE) sequence of MRI.

METHODS

A total of 26 patients with LAL reconstruction were recruited in this study, including 16 using semitendinosus allografts and 10 using semitendinosus autograft. All of them were diagnosed as chronic ankle instability and accepted anatomic reconstruction. The American Orthopedic Foot and Ankle Society (AOFAS) score, Karlsson score, and radiological evaluation using MRI UTE scanning were extracted from each patient. The comparative analysis of the clinical assessments and UTE-T2* values were performed between the patients using autografts and allografts.

RESULTS

For the allograft group, the mean AOFAS score improved from 69.9 ± 13.3 to 94.8 ± 5.4 (P = 0.000), and the mean Karlsson score improved from 70.3 ± 12.2 to 93.8 ± 5.6 (P = 0.000). For the autograft group, the mean AOFAS score improved from 68.4 ± 10.0 to 94.7 ± 5.0 (P = 0.000), and the mean Karlsson score improved from 64.5 ± 14.4 to 95.0 ± 5.8 (P = 0.000). No significant differences were found between the allograft and autograft neither before (AOFAS P = 0.756, Karlsson P = 0.285) nor after (AOFAS P = 0.957, Karlsson P = 0.574) surgery. While the UTE T2* values in allograft were higher than those of autograft group both in anterior talofibular ligament (8.3 ± 1.0 vs 7.6 ± 1.1 P = 0.027) and intra-tunnel graft (7.8 ± 0.6 vs 7.2 ± 0.8 P = 0.045).

CONCLUSION

Both allograft and autograft reconstructions could get an ideal patient satisfaction and clinical functional outcomes at the follow-up. Higher T2* values were found in allograft group which indicated that autograft had some superiorities in respect of revascularization process, collagen structure, water content, and tendon properties.