Recurrent patellar dislocation patients with high-grade J-sign have multiple structural bone abnormalities in the...

Area of Science:

• Orthopedic Surgery
• Radiology
• Biomechanical Engineering

Background:

• Recurrent patellar dislocation (RPD) is often associated with underlying structural bone abnormalities.
• Preoperative assessment of these abnormalities is crucial for effective treatment planning.

Purpose of the Study:

• To investigate the correlation between preoperative J-sign grading and the presence and severity of structural bone abnormalities in patients with RPD.
• To determine if higher J-sign grades are indicative of more significant osseous abnormalities.

Main Methods:

• Retrospective analysis of 256 RPD patients over 5 years.
• Patients categorized into low, moderate, and high J-sign groups.
• Assessment of trochlear dysplasia, femoral anteversion angle, knee torsion, TT-TG distance, and Caton-Deschamps index.
• Statistical comparison using the chi-squared test.

Main Results:

• Trochlear dysplasia (78.5%) and increased TT-TG distance (47.4%) were the most prevalent abnormalities.
• Higher J-sign grades were significantly associated with increased femoral anteversion angle, patella alta, knee torsion, and trochlear dysplasia (p < 0.001).
• Patients with high-grade J-sign frequently presented with multiple (≥2) bony abnormalities (90.2%) and severe (≥4) abnormalities (40.7%).

Conclusions:

• A high-grade J-sign in RPD patients strongly correlates with multiple structural bone abnormalities.
• These findings highlight the importance of evaluating and addressing osseous malalignments in patients with high-grade patellar mal-tracking.
• Preoperative identification of these correlated bone structures can guide surgical and conservative management strategies.