Modifications of the Fulkerson osteotomy: a pilot study assessment of a novel technique of dynamic intraoperative determination of the adequacy of tubercle transfer.

Medial transfer of the tibial tubercle is commonly implemented to correct patellar alignment in patients with patellar instability. However, the extent of transfer needed is difficult to determine. This article reports a pilot-study experience with a novel technique employing intraoperative femoral nerve stimulation to better determine the distance of tubercle transfer required for proper patellar tracking. This pilot study is a case series involving seven knees, all with a clinical history of dislocation, evidence of maltracking, and excessive medial patellofemoral ligament (MPFL) laxity to the point of producing a positive apprehension sign. All seven knees received femoral nerve stimulation for patellar tracking assessment as part of a modified Fulkerson osteotomy. All knees received clinical follow-up for a minimum of 24 months. Six of the seven cases in this series remained stable during two years of follow-up. Through these findings we conclude that the use of femoral nerve stimulation for patellar tracking assessment may be associated with a sufficiently high rate of success to warrant more extensive investigation.