Diagnosis and treatment of the medial-extension type of posterior malleolar fractures / 中华骨科杂志

ABSTRACT

Objective o evaluate the characteristics and treatments of the medial-extension type of posterior malleolar fractures.Methods Data of 75 patients with posterior malleolar fractures from May 2007 to December 2010were retrospectively analyzed.13 patients whose X-ray showed Cotton fracture while CT scan showed medial-extension type of posterior malleolar fractures were involved in this study.There were 8 males and 5 females,with an average age of 40.3 years old (range,15-75 years).The mechanisms of injuries were as follow6 patients with falling injury,4 patients from motor vehicle accidents and 3 patients from severe sprain.All the patients combined with distal fibular fracture.The preoperative clinical manifestations included foot and ankle swelling,deformity and restricted movement.The fracture line could be found on coronary X-ray.10 of those patients had double lines sign in medial malleolus.According to Haraguchi CT scan classification system,8 patients were Type Ⅰ fractures (61.6％,8/13),3 with Type Ⅱ fractures (23％,3/13),and 2 with Type Ⅲ fractures (15.4％,2/13).Posterior medial incision,cannulared screws after reduction were conducted.Wound and fracture healing were recorded postoperatively.Function was evaluated according to Baird-Jackson criterion.Results All 13 cases had been followed up for 8-45 months (mean 16 months).Post-operation X-ray showed articular surface displacement was less than 1mm; widening of the medial ankle mortise was no more than lmm; anatomy reduction was achieved or approximately achieved.All cases got union and the union period was 12-20 weeks with an average of 15.1 weeks.The incisions were primary healed in all patients.According to Baird-Jackson criterion,10 cases were excellent and 3 were good.76.9％(10/13) patients got excellent results.No instrument failure,fracture displacement,and infection were found.All patients could walk without accessory appliance.Conclusion Most of medial-extension type of posterior malleolar fractures have articular cartilage damage.It may be caused by rotational force combined with axial load.It needs open reduction and internal fixation early.The posterior medial incision has certain superiority.