Infraspinatus muscle diameter following posterior surgical approach for scapular fractures: A descriptive observational study of muscle changes and their relationship with shoulder pain and function

Background: Scapular fractures are relatively uncommon but can result in significant morbidity. Understanding their demographic characteristics, fracture mechanisms, associated injuries, radiological dimensions, and functional outcomes is crucial for effective management. This study describes postoperative changes in infraspinatus muscle diameter following the posterior (Judet) surgical approach. It explores their relationship with shoulder pain and its impact on function.Methods: Nineteen participants meeting the inclusion criteria were enrolled in the study. Demographic data, fracture characteristics, associated injuries, and radiological findings were collected. Ultrasound measurements of the infraspinatus and supraspinatus muscle diameters were performed bilaterally at six-month follow-up, with the radiologist blinded to clinical data. Fatty degeneration was graded using the Goutallier classification on postoperative CT. Functional outcomes were assessed using the American Shoulder and Elbow Surgeons (ASES) performance and pain scores. Statistical analysis was performed to explore relationships between variables.Results: Most participants were male, with a mean age of ۳۵.۹۵ years. Motorcycle accidents were the leading cause of fractures. Associated injuries were present in ۲۱.۱% of participants, with concurrent fractures in the lower extremities being the most common. Radiological evaluation revealed a statistically significant reduction in infraspinatus muscle diameter between healthy and fractured shoulders, but no significant difference for supraspinatus (p=۰.۲۳۳). No significant association was found between muscle diameter reduction and functional outcomes or pain scores. Functional outcomes were generally favorable, with most participants reporting high ASES scores.Conclusion: This descriptive study provides valuable insights into scapular fractures by examining key factors, including demographic characteristics, fracture mechanisms, associated injuries, radiological dimensions, and functional outcomes. The primary finding is a significant reduction in infraspinatus muscle diameter following the posterior (Judet) surgical approach for scapular fractures. However, this reduction was not significantly associated with shoulder pain (p=۰.۴۵) or functional outcomes (p=۰.۳۸) at six-month follow-up. These findings suggest that while measurable muscle atrophy occurs, it may not directly translate to short-term clinical impairment. Longer-term follow-up and studies with preoperative measurements are needed to determine the clinical significance of these morphologic changes.

کلیدواژه ها:

shoulder ، Scapula ، Fractures ، Posterior ، Surgical Approach ، Pain