Presentation
Elbow pain post sparring.
Patient Data
No fracture identified. Alignment within normal limits. No joint effusion. Mild insertional triceps enthesopathy. 13 mm long well-corticated ossicle projects posterior to the elbow joint. Posterior elbow joint soft tissue swelling.
The triceps tendon is intact with good elbow range of motion on examination. Within the mid triceps tendon is a 14 mm long ossicle with intact fibers both proximal and distal. Small partial thickness tear at the medial aspect of the distal triceps myotendinous junction. Minimal triceps insertional enthesopathy. Subcutaneous edema with hemorrhage within the olecranon bursa.
Case Discussion
The initial working diagnosis based on the x-ray was a large fractured olecranon osteophyte / triceps rupture as the patient had some tenderness, limited range of motion and posterior elbow soft tissue swelling. On ultrasound, no triceps rupture was demonstrated and the calcific fragment was lying within the triceps tendon. It is presumed that this is an os patella cubiti, an uncommon sesamoid bone.