Postoperative Reverse Shoulder Arthroplasty Angle Is Not Correlated with Patient-Reported Outcomes or Range of Motion

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Radiology

Background:

• Reverse shoulder arthroplasty (RSA) is a common procedure for complex shoulder conditions.
• Understanding factors influencing RSA outcomes is crucial for optimizing patient results.
• The postoperative angle of the RSA implant may potentially affect shoulder function and patient satisfaction.

Purpose of the Study:

• To investigate the correlation between postoperative reverse shoulder arthroplasty (RSA) angle and patient-reported outcome measures (PROMs).
• To determine the relationship between postoperative RSA angle and range of motion (ROM) after surgery.
• To assess if RSA angle as a continuous variable influences functional recovery in patients with modern implants.

Main Methods:

• Retrospective review of 142 patients undergoing primary RSA with a minimum 2-year follow-up.
• Measurement of preoperative and postoperative RSA angles using radiographs.
• Collection of PROMs (ASES, VAS, SANE) and ROM (external rotation, internal rotation, forward flexion) data.
• Statistical analysis using Pearson and Spearman correlation to assess relationships.

Main Results:

• No significant correlation was found between postoperative RSA angle and PROMs (ASES, VAS, SANE).
• Final range of motion (external rotation, internal rotation, forward flexion) also showed no significant association with postoperative RSA angle.
• Patients demonstrated varying degrees of improvement in PROMs, achieving minimal clinically important differences.
• A positive correlation was observed between higher postoperative RSA angle and higher preoperative RSA angle.

Conclusions:

• Postoperative RSA angle is not correlated with patient-reported outcomes or range of motion.
• The inclination of the postoperative RSA angle, especially without significant outliers, may not be detrimental to patient outcomes.
• These findings suggest that focusing solely on achieving a specific postoperative RSA angle may not be necessary for successful patient recovery.