# Combined Patellofemoral Arthroplasty With Patellar Realignment: Surgical Technique and Clinical Outcomes in a Retrospective Case Series

## TL;DR

This study examines a surgical technique combining patellofemoral arthroplasty and patellar realignment in young patients with patellar issues, showing improved outcomes with minimal complications.

## Contribution

The paper introduces a standardized dual-surgeon technique for combined patellofemoral arthroplasty and patellar realignment.

## Key findings

- Combined PFA and patellar realignment improved patient-reported outcomes with minimal complications.
- One case of periprosthetic patellar fracture occurred, but no re-dislocation or infections were observed.
- Knee Injury and Osteoarthritis Outcome Score Joint Replacement scores improved by an average of 14.8 points.

## Abstract

Isolated patellofemoral joint arthritis with patellar malalignment in young patients presents a unique challenge, as these patients typically wish to avoid early total knee arthroplasty. The purpose of this retrospective case series is to describe a standardized dual-surgeon technique for combined patellofemoral arthroplasty (PFA) with patellar realignment using medial patellofemoral ligament reconstruction or tibial tubercle osteotomy and to evaluate early clinical and patient-reported outcomes.

A retrospective review was conducted on patients who underwent combined PFA and patellar realignment by a fellowship-trained arthroplasty surgeon and fellowship-trained sports surgeon. Outcomes including implant survivorship, functional outcomes, complications, and patient-reported measures (Knee Injury and Osteoarthritis Outcome Score Joint Replacement, Patient Reported Outcomes Measurement Information System (PROMIS), Global Physical Health, PROMIS Global Mental Health, and Forgotten Joint Score) were assessed.

Eleven knees in 9 patients were included (55.5% female; median age 41 ± 13.4 years; median body mass index 26 ± 6.2). All knees had isolated patellofemoral arthritis. Nine knees underwent PFA with medial patellofemoral ligament reconstruction for instability or dislocation, while 2 underwent PFA with tibial tubercle osteotomy for patella alta. Two patellae were chronically dislocated, additionally requiring lateral release. Six knees had prior failed stabilizing procedures. The mean operative time was 121 minutes (94–161), with a mean follow-up of 24.0 ± 11.5 months. One patient experienced a periprosthetic patellar fracture at 10 months, followed by a refracture at 14 months, requiring open reduction and internal fixation and extensor mechanism repair. No cases of re-dislocation, maltracking, infections, wound complications, or other medical issues occurred. Knee Injury and Osteoarthritis Outcome Score Joint Replacement scores improved by an average of 14.8 ± 11 points.

Combined PFA and patellar realignment surgery can be done efficiently and is associated with improved patient-reported outcomes, with complications limited to a single case of periprosthetic patellar fracture.