Patellofemoral realignment: dynamic intraoperative assessment

Abstract

We describe a method of dynamic assessment of patellar tracking intraoperatively during a Fulkerson osteotomy. We utilize an electrically conductive catheter intraopertively to directly stimulate the femoral nerve to cause quadriceps muscle contraction. The resultant active knee extension allows dynamic assessment of patellofemoral tracking prior to and after final Fulkerson fixation. This dynamic intraopertive technique allows us to approximate in vivo patellofemoral motion better than with passive motion assessment.

Figure 1

Schematic of needle localization for placement of femoral nerve stimulator.

Figure 2

Patellar position just prior to quadriceps stimulation.

Figure 3

Quadriceps stimulated with central patellar tracking.