Fig a. Distal clavicle osteolysis. Cortical irregularity and sclerosis of the distal clavicle articular surface with subtle erosive change.
Fig b. Amorphous mineralization within the subacromial interval, which may represent chronic calcified bursitis.
There are many causes of chronic shoulder pain, often related to overuse or joint instability in younger patients and degeneration in older patients. Common radiographic abnormalities worth noting:
- Distal clavicle osteolysis
- Cortical irregularity and erosive changes at the articular surface of distal clavicle most commonly due to repetitive microtrauma, classically seen in weightlifters.
- Overuse injury/bursitis
- Common in subacromial space, radiographically visible only if chronic/partially calcified.
- Common in subacromial space, radiographically visible only if chronic/partially calcified.
- Possible osseous contributors to subacromial impingement/rotator cuff injury
- Comon examples include type III “hooked” acromion, acromioclavicular joint osteophytes, os acromiale
- Narrowing of acromiohumeral distance seen in chronic full thickness rotator cuff tear
- Calcific tendonosis
- Amorphous/globular calcific density typically near insertion of rotator cuff tendons
- Common presentation of hydroxyapatite crystal deposition disease (HADD)
- Osteoarthritis
- Often posttraumatic, characterized by joint space narrowing, osteophyte formation, subchondral cysts, and sclerosis.
- Often posttraumatic, characterized by joint space narrowing, osteophyte formation, subchondral cysts, and sclerosis.