Differential Diagnosis for Avulsion Injury Involving the Head of the Second Metacarpal
- Single most likely diagnosis
- Boxer's fracture with associated avulsion injury: This is the most likely diagnosis given the location and nature of the injury. The second metacarpal is commonly involved in boxer's fractures, and an avulsion injury could occur simultaneously.
- Other Likely diagnoses
- Fracture of the second metacarpal with intra-articular extension: The avulsion injury could be part of a more complex fracture involving the joint surface.
- Gamekeeper's thumb (ulnar collateral ligament injury): Although more commonly associated with the first metacarpal, a similar mechanism could potentially injure the ligaments around the second metacarpal.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Osteonecrosis of the metacarpal head: Disruption of blood supply due to the avulsion injury could lead to osteonecrosis, which would have significant long-term implications.
- Infection (osteomyelitis or septic arthritis): Open fractures or significant soft tissue damage increase the risk of infection, which could be devastating if not promptly addressed.
- Rare diagnoses
- Metacarpal head osteochondritis dissecans: A rare condition where a piece of cartilage and bone becomes detached, potentially related to or exacerbated by the avulsion injury.
- Non-accidental trauma: Although rare, it's essential to consider the possibility of non-accidental injury, especially in vulnerable populations.