Primary Synovial Chondromatosis of the Elbow Joint Presenting with Ulnar Nerve Compression and Restricted Range of Motion: A Case Report

Introduction: Primary synovial chondromatosis is an uncommon benign disorder characterized by cartilaginous metaplasia of the synovium, leading to the formation of intra-articular nodules. The elbow joint is an unusual site, and neurological involvement, particularly ulnar nerve compression, is exceptionally rare. Case Report: A 42-year-old female presented with progressive pain, stiffness, and weakness of grip in her dominant elbow, accompanied by numbness along the ulnar border of the hand. Radiographs revealed a single calcified nodule in the medial compartment of the elbow, and magnetic resonance imaging (MRI) demonstrated a well-defined intra-articular mass compressing the ulnar nerve. Nerve conduction studies confirmed delayed conduction across the elbow. The patient underwent open excision of the lesion via a medial approach with decompression of the ulnar nerve. Histopathology confirmed primary synovial chondromatosis. At the 6-week follow-up, the patient showed improvement in pain and strength with enhanced ulnar conduction parameters. At 6 months, she regained full motion and complete functional recovery without recurrence. Conclusion: Solitary synovial chondromatosis of the elbow causing ulnar nerve compression is extremely uncommon. Early diagnosis with MRI and timely surgical decompression can prevent permanent neurological deficits and ensure excellent functional outcomes.