Differential Diagnosis for 45 YOM with Distal Forearm Swelling

• Single Most Likely Diagnosis
  • Compartment Syndrome: This condition is characterized by increased pressure within a muscle compartment, leading to pain, swelling, and potentially, nerve and muscle damage. The presence of crepitus (a grating or bubbling feeling) upon palpation, pain with wrist flexion and extension, and swelling in the forearm are indicative of compartment syndrome. The absence of trauma history does not rule out this diagnosis, as it can also be caused by intense exercise, tight clothing, or other non-traumatic factors.
• Other Likely Diagnoses
  • Cellulitis or Infection: Although the overlying skin is described as normal, early stages of cellulitis or other infections could present with swelling and pain without significant skin changes initially. The presence of crepitus might suggest gas in the tissues, pointing towards a gas-producing infection.
  • Deep Vein Thrombosis (DVT): While less common in the forearm, DVT could cause swelling and pain. However, the presence of crepitus and specific pain with wrist movements makes this less likely.
  • Tenosynovitis: Inflammation of the tendon sheaths around the wrist and forearm could cause pain with movement and swelling. However, crepitus is not typically a primary symptom.
• Do Not Miss Diagnoses
  • Gas Gangrene: This is a life-threatening condition caused by Clostridium perfringens infection, characterized by gas production in tissues, which could explain the crepitus. It requires immediate medical attention.
  • Necrotizing Fasciitis: A severe infection that affects the tissue beneath the skin and surrounding muscles and organs. It is a medical emergency and could present with similar symptoms, including pain out of proportion to the appearance of the skin.
• Rare Diagnoses
  • Forearm Osteomyelitis: An infection of the bone in the forearm, which could cause pain, swelling, and might have systemic symptoms like fever. It's less common and usually follows trauma or a contiguous infection.
  • Eosinophilic Fasciitis: A rare condition characterized by inflammation of the fascia, which could present with swelling, pain, and sometimes, a feeling of crepitus due to fascial thickening. It's a diagnosis of exclusion and often requires biopsy for confirmation.