In an adult patient with shoulder pain, limited range of motion and mechanical symptoms, what is the significance and recommended management of a loose body seen superior to the glenoid on a shoulder radiograph?

Management of Loose Body Superior to Glenoid on Shoulder Radiograph

A loose body superior to the glenoid on shoulder radiograph requires advanced imaging with CT (without contrast) to characterize the fragment and assess for underlying pathology such as synovial chondromatosis, osteochondral fracture, or degenerative joint disease, followed by arthroscopic removal if the patient has mechanical symptoms, pain, or limited range of motion. 1

Initial Diagnostic Approach

Radiographic confirmation is essential but insufficient for complete evaluation. While standard shoulder radiographs (AP views in internal and external rotation plus axillary or scapular Y view) can identify loose bodies, they cannot fully characterize the fragment size, precise location, or associated soft tissue pathology 2, 3.

Advanced Imaging Selection

CT without IV contrast is the preferred next imaging study for several critical reasons:

• Superior characterization of osseous fragments: CT provides detailed visualization of loose body size, number, and exact anatomical location that plain radiographs cannot demonstrate 1, 4
• Assessment of glenoid morphology: CT with 3D reconstruction can identify underlying glenoid rim fractures, erosions, or bone loss that may have generated the loose body 4, 5
• Surgical planning: CT is essential for determining arthroscopic versus open surgical approach and identifying all fragments preoperatively 4, 6

MR arthrography (rating 9/9) should be obtained if labral pathology is suspected as the underlying cause, particularly in younger patients with history of instability or trauma, since it is the reference standard for detecting labral tears with 86-100% sensitivity 1, 7. However, MRI cannot adequately visualize calcified or ossified loose bodies 1.

Differential Diagnosis Considerations

The location "superior to glenoid" narrows the differential:

• Synovial chondromatosis: Can produce multiple loose bodies throughout the joint; arthroscopic retrieval of over 100 loose bodies has been successfully reported 6
• Osteochondral fracture fragment: May result from prior trauma, dislocation, or impaction injury 4, 5
• Degenerative changes: Osteophyte fragmentation in osteoarthritis can produce loose bodies 8
• Glenoid rim fracture: Anterior or superior glenoid rim fractures can create displaced fragments; CT with 3D reconstruction is superior to radiography for detecting these 4, 5

Management Algorithm

For symptomatic patients (pain, mechanical symptoms, limited ROM):

1. Obtain CT shoulder without contrast to fully characterize the loose body and assess for additional fragments or underlying pathology 1, 4
2. Consider MR arthrography if patient age <35 years, history of instability, or concern for labral pathology as the underlying cause 1, 7
3. Refer to orthopedic surgery for arthroscopic removal once imaging is complete; arthroscopy provides excellent visualization and faster recovery compared to open arthrotomy 6

For asymptomatic patients (incidental finding):

• Serial radiographic follow-up at 3-6 month intervals to monitor for fragment migration, increasing size, or development of symptoms 1
• Proceed to CT and surgical referral if symptoms develop or fragment enlarges 1

Critical Pitfalls to Avoid

Relying solely on standard radiographs will miss:

• Additional loose bodies not visible on plain films (CT identifies fragments missed on radiography in up to 50% of cases) 4
• Underlying glenoid rim pathology that generated the fragment 5
• Associated labral or rotator cuff injuries, particularly in older patients 2

Delaying surgical referral in symptomatic patients risks progressive cartilage damage from the loose body acting as an abrasive "third body" within the joint 6.

Attempting arthroscopic retrieval without adequate preoperative CT imaging may result in incomplete removal if multiple fragments are present, leading to persistent symptoms and need for revision surgery 6.