Thumb Injury - Baseball

HISTORY: 20-year-old right-handed male with painful clicking and snapping over the left thumb. Patient denied recent trauma or change in activity. Notably, seven years ago during baseball practice, he sustained a left-hand injury while catching 80 mph fastballs with an infielder’s glove. Immediately following the incident, he recalled experiencing significant pain swelling of his left hand and was unable to move his thumb. Radiographs at the time revealed normal findings and patient did not seek further medical care. Seven years later, pain has remained unchanged, and he has developed new onset grip weakness and snapping of the left thumb. PHYSICAL EXAM: Examination revealed a flexed and adducted thumb with swelling of the wrist, moderate tenderness to palpation of the dorsoradial aspect of the left wrist and thumb MCP joint. Inability to actively extend the thumb from a flexed position at MCP, however, if thumb MCP passively placed to neutral he could maintain and initiate thumb IP extension. Able to make a composite fist and positive Finkelstein test. Intact neurovascular function in the left median, radial, and ulnar nerve distributions. DIFFERENTIAL DIAGNOSIS: 1. Sagittal band rupture of the thumb 2. EPL, EPB tendon injury 3. De Quervain’s tenosynovitis 4. Chronic gamekeeper’s thumb TESTS AND RESULTS: Left wrist PA, PA oblique, and lateral radiographs:— ulnar positive variance with mild widening of the distal radioulnar joint space. No acute osseous abnormality. Mild soft tissue swelling of the thumb MCP joint and radial styloid. MRI left fingers without contrast:— chronic injury of the proper and accessory ulnar collateral ligaments of the thumb. Normal appearance of the radial collateral ligament. FINAL/WORKING DIAGNOSIS: Radial sagittal band rupture of the thumb with ulnar subluxation of EPL tendon. TREATMENT AND OUTCOMES: 1. Immobilization with custom, static, left wrist-thumb orthosis for 4 weeks. 2. Isolated, gentle, pain free thumb and wrist ROM exercises started after use of orthosis for 4 weeks. 3. Therapeutic ultrasound performed over the first extensor compartment of left wrist. 4. Strengthening exercises with therapy putty for left wrist and thumb 5. Full, painless thumb ROM with successful return to physical activity at 6 weeks after initial therapy session.