TROCHLEOPLASTY FOR SEVERE DYSPLASIA OF THE FEMORAL SULCUS

Abstract

Introduction and Aims: Dysplasia of the femoral sulcus is one component that may be present in patients presenting with patellar instability. Rarely the dysplasia is so severe that a dome rather than groove is present. Dejour has reported an operation that deepens the groove, unlike the Albee which elevates it. This study reports the development of a modification of the Dejour trochleoplasty reporting the clinical and radiological results.

Method: A consecutive case series of the first 15 patients (17 knees) who underwent a trochleoplasty with a minimum one-year follow-up. There were 11 females and four males with an age range from 15 to 47 years old. Nine patients had had previous operations. The pre-operative length of symptoms ranged from one to 30 years. The patellar instability was managed operatively using the Dejour protocol measuring the patellar height, boss height, tibial tubercle-trochlear groove distance and patellar tilt angle. The Kujala score was used for functional assessment and a subjective assessment was also made. CT scans as well as plain films were used for radiological assessment. The operative technique changed in the light of experience from metallic to absorbable screws as the former abraded the patella.

Results: The boss height was reduced from an average of 7.5mm to 1mm (normal 0mm). Tracking became normal in 11 knees and had a slight J-shape in six. Seven knees had a mild residual apprehension. Five patients were very satisfied, eight were satisfied, and two were disappointed. The Kujala score improved from an average of 48 to 73 out of 100. Three patients returned to full sports. Eight patients required further operations apart from the removal of metallic screws in 10 knees. Five of these were arthrolysis for stiffness at about six weeks post-operatively. As a result, patients were placed on a continuous passive motion machine for three to four days to avoid this. One patient went on to have autologous chondrocyte implantation for a defect on the lateral femoral condyle involving the tibial surface. This was after a new injury following a return to sports and not in the area affected by the trochleoplasty.

Conclusion: Trochleoplasty for severe dysplasia of the femoral sulcus is a developing procedure. It requires careful attention to detail. For a rare condition the results have been gratifying with an acceptable level of complications. It is not recommended that this procedure be performed by general orthopaedic surgeons.