Posterior Anti-Rotatian Plate Combination With Cancellous Screws For The Anagement Of Unicondylar Hoffa Fractures

Objective:To investigate the clinical efficacy of anti-rotation plate plus cancellous screws for fixation of unicondylar Hoffa fractures and systematically analyse the injury mechanism, diagnosis, surgical technique, radiological data, clinical results of Hoffa fractures.Methods:we reviewed 9 unicondylar Hoffa fractures treated by one surgeon from March 2009 to April 2014. They were 7 males and 2 females, with an average age of 41years (range,from 28 to 63 years). There were 6 fractures involving lateral femoral condyle while 3 fractures involving medial femoral condyle. Each patient suffered a high-energy injury, including 5 patients by motor vehicle accident,2 patients by fall from height, and 2 patients by bruise injury. According to Letenneur’s classification,4 fractures were type Ⅰ,2 fractures was type Ⅱ and 3 fractures were type Ⅲ. All fractures were fixed with anti-rotation plate plus cancellous screws by open reduction through a typical posterolateral approach or posteromedial approach. Postoperatively, The affected knee began immediate unrestricted range of mation. The limited weight bearing started at the fourth week after surgery, and all patients were permitted full weight bearing at eighth week. Reduction quality and radiological results were assessed in standard anteroposterior and lateral radiographs. Clinical results were evaluated by Knee Society scores after average 24 months follow-up time.Results:All fractures healed at a mean period of 4.0 months. Long-term follow-up (average 34 months, range 24-50 months) was available for all patients.7 patients achieved anatomical reduction while 2 patients achieved satisfactory reduction. There was no loss of reduction or failure of fixation. Early complication was encountered in one case with wound infection but healed within one week owing to with help of efficient antibiotics. Late complication was found in one case with stiffness and pain of the affected knee. The final clinical results was excellent in 4 patients, good in 4 patients and poor in 1 patient.Conclusion:Isolated Hoffa fractures are rare intraarticular injury and there is a highly likelihood of these fractures being missed by an orthopaedic surgeon. Oblique radiographs and CT scans can help to confirm and define these fractures, especially in cases of undisplaced fractures. Typical posterolateral/posteromedial approach described in our study can provide the direct visualization of the fracture and articular surface. Internal fixation using anti-rotation plate combination with cancellous screws can obtain a stable and rigid fixation and lead to a good functional outcome in the long term.