[Effectiveness of very low profile/variable angle locking plate internal fixation in treatment of posterior Pilon fractures extending to medial malleolus by posteromedial approach].

OBJECTIVE

To evaluate the effectiveness of very low profile/variable angle locking plate (VLP) internal fixation for posterior Pilon fractures extending to the medial malleolus by posteromedial approach.

METHODS

A retrospective analysis was made on the clinical data from 13 patients with posterior Pilon fractures extending to the medial malleolus between December 2011 and August 2012. There were 4 males and 9 females with an average age of 48.9 years (range, 23-68 years). Fractures were caused by falling in 9 cases and by traffic accident in 4 cases. The locations were the left ankle in 6 cases and the right ankle in 7 cases. According to the Orthopedic Trauma Association (OTA) classification, 6 cases were rated as type 43B1, 4 cases as type 43B2, and 3 cases as type 43B3. Twelve cases had fibular fractures, including 11 cases of Denis-Weber type B, 1 case of Denis-Weber type C. The interval of injury and operation was 7-14 days (mean, 11.4 days). Open reduction was performed and VLP internal fixation was used for posterior malleolar fracture by posteromedial approach.

RESULTS

Primary healing of incision was obtained in all patients. Tibial nerve palsy was observed in 2 cases, and was cured after oral administration of mecobalamin. Twelve cases were followed up 12-18 months (mean, 14.5 months). According to the Burwell-Charnley's radiological evaluation system, 11 cases achieved anatomical reduction, 1 case achieved fair reduction. The fracture union time was 3-6 months (mean, 3.7 months). No loosening or breakage of internal fixation occurred during follow-up. According to the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale, the results were excellent in 7 cases, good in 4, and fair in 1; the excellent and good rate was 91.7%.

CONCLUSION

VLP internal fixation for posterior Pilon fractures extending to the medial malleolus by posteromedial approach can achieve good short-term effectiveness. The high quality of reduction is acquired under direct vision with low rate of soft tissue complications.