The Biomechanical Effects of Fatigue on Drop-Jump Performance in Basketball Athletes

HISTORY: An 18-year-old high school football player presented to the clinic following an in-game injury to his left 5th digit during a tackling attempt. History is significant for 2 previous football injuries to the same digit. The initial injury occurred 1 year prior with pain and swelling of the 5th PIP joint with limited range of motion. He returned to normal following weeks of buddy taping. Second injury occurred 2 weeks prior to current injury, after direct, traumatic contact to the PIP joint. Again there was pain, swelling, and improvement with buddy taping. The final injury requiring medical attention occurred during a tackling attempt with unclear mechanism. There was no sensation of dislocation. Pain localized to the dorsal MCP joint (MCPJ) without radiation. PHYSICAL EXAMINATION: On inspection, there was mild soft tissue swelling about the dorsal 5 MCPJ. Maximal tenderness to palpation was over the dorsal MCPJ, with secondary tenderness at the ulnar and radial PIP. On active ROM his 5 digit was unable to extend from the flexion biased natural resting hand position, which created an extensor lag of 1-2cm from the horizon at the MCP and extensor lag of 15o at the DIP. Active flexion was limited at the MCPJ and DIPJ by 10-15o compared to the normal, contralateral side. There was 0.5cm flexion lag of the 5th digit making a fist. Strength was 4/5 for FDS and FDP with pain reproduction. He had difficulty firing the extensor digiti minimi DIFFERENTIAL DIAGNOSIS: 1. Metacarpal fracture 2. Proximal phalanx fracture 3. Mallet finger 4. MCP extensor sheath injury TEST AND RESULTS: Hand X-rays: Small avulsion fracture off the volar aspect of the base of the 5th middle phalanx. MSK Ultrasound: Intact distal extensor mechanism MRI hand: Distal 5 metacarpal bone contusion without acute fracture, MCPJ capsular sprain with low-grade partial tear of the ulnar collateral ligament, and joint effusion. FINAL WORKING DIAGNOSIS: Left 5 MCPJ capsule sprain, partial tear of the 5 MCP ulnar collateral ligament, and 5 metacarpal bone contusion TREATMENT AND OUTCOMES: 1. Immobilization with hand based intrinsic plus splint encompassing the 4th + 5th MCP for 4 weeks 2. No contact sports due to osseous edema and risk of fracture until 4 week follow up 3. Follow up in 4 weeks for x-rays 4. More follow up to be presented at the conference as patient returns