Patterns in Outcomes Reporting of Operatively Managed Pediatric Patellofemoral Instability: A Systematic Review and Meta-analysis

Abstract

Background:

Traumatic patellofemoral dislocation is a common injury in pediatric patients, and surgical treatment is often recommended. Increasingly, it has been recognized that clinical studies need to report age-appropriate treatment outcomes. However, the variability and appropriateness of outcomes reporting in the youth patellar instability literature are unknown.

Purpose:

To analyze the patterns of outcomes reporting in studies published in high-impact orthopaedic journals after operative management of pediatric patellar instability.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

Six high-impact orthopaedic journals were searched using PubMed and EMBASE to identify studies reporting outcomes of operative management of pediatric patellar instability. Studies containing adults were excluded. Clinical and radiographic outcomes were recorded from included articles. Descriptive statistics were calculated for overall instability recurrence rates, return-to-activity rates, and changes in Kujala and Tegner scores.

Results:

Of 545 identified articles, 8 studies met the inclusion criteria. These studies encompassed 213 patients and 230 knees (mean age, 13.2 years; range, 4.5-18.3 years). Seven of 8 studies reported patients’ physeal status, but only 4 studies limited their outcomes reporting to patients with open physes. Two studies reported postoperative radiographic measures, and 5 studies reported preoperative radiographic findings. Six studies reported patient-reported outcome measures (PROMs). Seven unique PROMs were reported. All but one study reported complication rates and types of complications. The mean postoperative change in Tegner scores was −0.07 (range, −0.6 to 1.0). Among studies examining medial patellofemoral ligament reconstruction with adequate data, the mean return-to-activity rate was 86% (range, 81%-92%), the instability recurrence rate was 3% ± 20%, and the mean improvement in Kujala scores postoperatively was 22.1 (range, 19.9-26).

Conclusion:

There is a need for more pediatric-specific outcomes studies regarding operatively managed traumatic patellofemoral instability. Of the outcomes reported, both radiographic outcomes and PROMs should be standardized. Among radiographic outcomes, there is a need for more studies that report tibial tubercle–trochlear groove distances and use Caton-Deschamps and/or Blackburne-Peel indices to assess patellar height. Among PROMs, there is a need for studies that use PROMs validated in pediatric populations, such as the International Knee Documentation Committee Pediatric Form or the Hospital for Special Surgery Pediatric Functional Activity Brief Scale.