Indications for the addition of a patellofemoral joint arthroplasty following a previous unicondylar knee arthroplasty- a literature review and Delphi consensus.

INTRODUCTION

The aim of this study was to establish an international consensus statement on the indications for the addition of a patellofemoral joint arthroplasty (PFJA) in patients with a unicondylar knee arthroplasty (UKA) and symptomatic progression of patellofemoral compartment osteoarthritis.

MATERIALS AND METHODS

A systematic review of the literature was conducted, and the results used to inform the development of a statement by an expert working group. This was then evaluated and modified, using a Delphi process, by members of the European Knee Society (EKS).

RESULTS

Forty-nine (round one) and forty-two (round two) EKS members took part in the Delphi process, with 83% agreement on the resulting consensus statement that the indications for this procedure are: (1) a well-functioning UKA in a satisfied patient with secondary osteoarthritis progression in the patellofemoral compartment (2), symptomatic patellofemoral compartment osteoarthritis with full thickness cartilage loss affecting the lateral facet of the patellofemoral joint (3), functional ligaments, including the anterior cruciate ligament (ACL) (4), a lateral tibiofemoral compartment with no cartilage damage greater than Ahlback Grade 1 (5), knee flexion ≥ 100° and extension loss ≤ 5° and (6) older patients with increased medical co-morbidities.

CONCLUSIONS

The simple addition of a PFJA to patients with an existing UKA and progression of patellofemoral compartment osteoarthritis is an attractive option. This EKS Delphi-derived consensus statement, which reached a strong consensus, can be used by clinicians to identify patients suitable for this procedure.