Summary

A retrospective study of 206 consecutive patients, conducted by a single surgeon, identified predictors of a positive J-sign and apprehension prior to patellofemoral stabilization surgery.

Abstract

Title: Predictors of Positive J-Sign and Apprehension Preceding Patellofemoral Stabilization Surgery

Objectives: Identify factors that are predictive of positive J-sign and apprehension preceding patellofemoral stabilization surgery.

Methods

A retrospective chart review, imaging evaluation, and collection of Patient-Reported Outcomes were conducted at a single institution for patients who underwent MPFL reconstruction for recurrent patellar instability by a single surgeon between 2016 and 2023. The study included 206 consecutive patients collecting information from the patient's initial visit through 1-year postoperative follow-up visit.

Results

This study included 160 females and 45 males with an average age of 25.0. The sulcus angle (p = 0.025) was found to be significantly higher for the 49% of patients with a positive pre-operative J-sign. For the 69% of patients with positive pre-operative apprehension, a higher sulcus angle (p= 0.025), higher lateral to central condylar height ratio (p = .031), and presence of patellar subluxation on MRI (p = 0.062) was found to be significant.

Conclusions

We identified several key factors predictive of a positive J-sign and apprehension prior to patellofemoral stabilization surgery. These findings suggest these imaging evaluations can potentially be used in surgical planning, contributing to better surgical outcomes and increased patient satisfaction.

Level of Evidence: Level III (prognostic)