Differential Diagnosis for a 19-year-old with no inversion

• Single most likely diagnosis:
  • Ankle sprain: This is the most common injury in individuals who experience ankle pain without inversion, as it can occur from various mechanisms such as landing awkwardly or twisting the ankle.
• Other Likely diagnoses:
  • Ankle fracture: Although less common than sprains, fractures can occur without inversion and should be considered, especially if there's significant pain or swelling.
  • Achilles tendonitis: Inflammation of the Achilles tendon can cause pain in the back of the ankle, which might not necessarily involve inversion.
  • Peroneal tendonitis: Similar to Achilles tendonitis, inflammation of the peroneal tendons can cause lateral ankle pain without a history of inversion.
• Do Not Miss diagnoses:
  • Osteochondral lesion of the talus: A potentially serious condition where a piece of cartilage and bone in the talus (ankle bone) becomes damaged. It might not always present with a clear history of inversion.
  • Compartment syndrome: A condition where increased pressure within a muscle compartment can lead to muscle and nerve damage. It's a medical emergency and can present with severe pain out of proportion to the injury.
• Rare diagnoses:
  • Stress fracture: Although rare in young adults without a significant training regimen, stress fractures can occur in the ankle bones and might not have a clear mechanism of inversion.
  • Neuroma: A benign growth of nerve tissue that can cause pain, usually between the toes but potentially in the ankle area, without a history of inversion.
  • Infection or osteomyelitis: Infections of the bone or soft tissue can cause ankle pain and should be considered, especially if there are signs of infection such as redness, warmth, or fever.