Patellar medial closing-wedge osteotomy in patello-femoral instability: Indications and outcomes

J Orthop. 2022 Jun 14:32:156-159. doi: 10.1016/j.jor.2022.06.005. eCollection 2022 Jul-Aug.

Abstract

Background: Patellofemoral (PF) instability is a syndrome involving several factors and conditions. Trochlear dysplasia (TD) has been shown to be the feature most frequently diagnosed in patients with OPI (Objective Patellar Instability). Even the patella might have an altered shape. Articulating during growth with an abnormal trochlea might lead the patellar posterior surface to modify accordingly, becoming congruent with the trochlear shape. A mismatch between the two articulating surfaces has a role in patellofemoral dislocations.Rarely and in case of a highly dysplastic patella, reshaping only the trochlear groove might lead subsequently to an incongruence between the two bones.When isolated sulcus-deepening trochleoplasty does not restore a congruent patellofemoral tracking tested perioperatively, further surgical procedures might be required.

Methods: A medial closing wedge patellar osteotomy (MCWPO) added to sulcus deepening trochleoplasty should be performed to create a congruent patellofemoral joint.Indications for this procedure are Wiberg type III or IV patella with an intraoperative abnormal patellar tracking after the sulcus deepening trochleoplasty procedure has been concluded.

Results: From January 2012 to August 2020, 21 (6 right and 15 left knees) sulcus deepening trochleoplasties with a concomitant medial closing wedge patellar osteotomy have been performed. The mean follow up was 35,25 months (ranging from 10 to 60 months). The average Kujala, IKDC and Lysholm score were respectively 70,14 ± 15,51; 55,75 ± 7,12 and 77,12 ± 14,80. No further patellar dislocation has been assessed in those patients during follow up.

Conclusion: This technique has shown good and promising clinical outcomes and should be considered when treating patients with a still unsatistactory patellofemoral tracking after the sulcus deepening trochleoplasty has been performed due to a patella-trochlea shape mismatch.

Keywords: Patella; Patellar closing wedge; Patellar osteotomy; Patollofemoral instability; Trochlea dysplasia.