Differential Diagnosis for 40 yo Female with Thumb Pain
Single Most Likely Diagnosis
- Gamekeeper's Thumb (Ulnar Collateral Ligament Sprain): This is the most likely diagnosis given the mechanism of injury (overextension while playing volleyball) and the location of pain and tenderness at the dorsal aspect of the base of the thumb. The ulnar collateral ligament is commonly injured in such scenarios, leading to pain, swelling, and bruising.
Other Likely Diagnoses
- Thumb Carpometacarpal Joint Sprain: The carpometacarpal joint of the thumb is susceptible to injury during overextension, which could lead to sprain and subsequent pain, swelling, and tenderness.
- Dorsal Thumb Contusion: Direct trauma to the dorsal aspect of the thumb during the fall or overextension could result in a contusion, explaining the bruising, swelling, and pain.
- Radial Collateral Ligament Sprain of the Thumb: Although less common than ulnar collateral ligament injuries, radial collateral ligament sprains can occur due to overextension or direct trauma, leading to similar symptoms.
Do Not Miss Diagnoses
- Scaphoid Fracture: Although the primary complaint is at the base of the thumb, a scaphoid fracture (which typically occurs with a fall onto an outstretched hand) could radiate pain to the area and must be considered due to its potential for serious complications if missed (e.g., avascular necrosis).
- Ganglion Cyst: While less likely given the acute onset after trauma, a ganglion cyst could cause pain and tenderness at the base of the thumb. However, it's crucial to differentiate this from more acute injuries.
- Infection (e.g., Cellulitis or Abscess): Any signs of infection (increased redness, warmth, swelling, or purulent discharge) must be promptly addressed to prevent serious complications.
Rare Diagnoses
- Osteochondritis Dissecans of the Thumb: A rare condition where a piece of cartilage and bone in the joint becomes damaged, potentially due to trauma. It could cause pain and tenderness but is less likely given the acute presentation.
- Tendinosis or Tendinitis of the Thumb Extensors: Chronic conditions that could be exacerbated by acute trauma, leading to pain and swelling at the base of the thumb. However, these are less likely given the recent onset after a specific injury.