We experienced a case of chondral injury of a shoulder joint by arm wrestling. The case is a thirty-three year-old male, a fireman. On 24th June,2001, while arm wrestling, he felt a strange sound from his shoulder joint when he rotated internally strongly at 30° abduction and the next second a forced external rotation forced his shoulder to be immobile with severe pain. The next day he consulted our clinic and complained of innability of elevation and severe pain. There was a swelling but no tenderness in his shoulder, but ROM was limited in all directions with severe pain. An apprehension sign existed at the position of external rotation. There were no Bankart lesions or Hill Sachs lesions on a plain X-ray film. A MRI showed an irregural joint surface of the glenoid, hematoma and a free body. An arthroscopy was done on 4th July 2001, a broad chondral defect was found both at the center of the humeral head and antero-inferior portion of the glenoid. IGHL showed an avulsion at 6 to 10 o'clock from the glenoid. A free body was removed and IGHL was re-attached to the glenoid over the chondral defect. Post operation, after three weeks immobilization ROM exercises were started. Now eighteen months have passed, he feels no pain, no apprehension, but some crepitation while moving to internal rotation from external rotation position. This case is different from ordinary shoulder dislocations both its mechanism and chondral lesion. We discussed these points and the treatment.
