MRI Study of Trauma-Induced Rotator Cuff Injuries and Their Correlation to Mechanism of Injury

Traumatic rotator cuff injury is a frequent cause of acute shoulder pain, weakness, and functional limitation. Unlike degenerative tears, trauma-related tears usually follow a definite injury event and may show specific imaging patterns depending on the mechanism of trauma. MRI allows detailed assessment of tendon integrity, tear morphology, retraction, muscle status, bone marrow edema, joint effusion, bursitis, and associated shoulder abnormalities. This study aimed to evaluate MRI findings in trauma-induced rotator cuff injuries and correlate them with the mechanism of injury.

This prospective observational study included 50 patients with acute shoulder trauma who underwent MRI of the affected shoulder. Patients with predominant chronic degenerative rotator cuff disease or non-traumatic shoulder pathology were excluded. Clinical history regarding the mode of injury and onset of symptoms was recorded. Mechanisms of injury were categorized as fall on an outstretched hand, direct impact to the shoulder, traction injury, lifting or overhead loading injury, and high-energy trauma. MRI was performed using standard shoulder sequences in multiple planes. Tendon involvement, tear type, partial-thickness tear grade, full-thickness tear size, tendon retraction, acute injury markers, muscle changes, and associated intra-articular or periarticular findings were assessed. Ellman grading was used for partial-thickness tears, and Cofield classification was applied for full-thickness supraspinatus tears wherever applicable.

The mean age of the study population was 47.98 ± 14.25 years. Male patients were more commonly affected, and right shoulder involvement was more frequent. The supraspinatus tendon was involved in all cases, either alone or as part of a multi-tendon injury pattern. Infraspinatus and subscapularis involvement were also identified, especially in more severe injuries. Partial-thickness tears were the most common tear pattern, while full-thickness tears and combined tear patterns were seen in selected cases. Tendon retraction, bone marrow edema, joint effusion, subacromial-subdeltoid bursitis, and acromioclavicular joint changes were observed in varying proportions. Mechanism of injury was significantly associated with tear type, full-thickness supraspinatus tear-size category, and bone marrow edema. High-energy trauma was predominantly associated with full-thickness tear components, larger supraspinatus tears, and bone marrow edema, whereas lower-energy mechanisms more commonly demonstrated partial-thickness tear patterns. No significant mechanism-based association was observed for Ellman grade, tendon retraction, or muscle edema.

MRI provides a comprehensive evaluation of trauma-induced rotator cuff injuries by characterizing tendon involvement, tear type and extent, tendon retraction, acute traumatic markers, and associated shoulder abnormalities. Correlation of MRI findings with the mechanism of injury may improve diagnostic confidence, assist in differentiating acute traumatic tears from chronic degenerative or acute-on-chronic pathology, and provide clinically relevant information for treatment planning.