Differential Diagnosis for Left Toe Pain

The patient presents with left toe pain that developed approximately 4 weeks ago, which he attributes to friction from exercising and his shoe rubbing against the toe. Given the history and symptoms, the following differential diagnoses are considered:

• Single Most Likely Diagnosis

  • Ingrown toenail: The patient's history of an ingrown toenail in the right foot, which was surgically removed, and the current presentation of toe pain after friction from a shoe, make ingrown toenail a highly plausible diagnosis. The absence of redness, drainage, or fever reduces the likelihood of infection at this stage, but it could still be an early stage or a complication of an ingrown toenail.

• Other Likely Diagnoses

  • Blister or friction injury: Given the patient's recent exercise and the toe rubbing against the shoe, a blister or a friction injury could be a likely cause of the pain.
  • Toe sprain or strain: Although less common, a sprain or strain from the exercise could also cause toe pain.
  • Bunion: The patient's history of ingrown toenails and the pain in the great toe could suggest an underlying bunion, especially if the shoe is exacerbating the condition.

• Do Not Miss Diagnoses

  • Osteomyelitis: Although the patient is afebrile and denies redness or drainage, osteomyelitis (bone infection) is a serious condition that could present with pain and should not be missed, especially in the context of a recent injury or trauma to the area.
  • Gout: Acute gout can present with sudden onset of pain, often in the great toe, and while the patient's history does not strongly suggest gout, it is a condition that should be considered due to its potential for severe pain and the need for specific treatment.
  • Diabetic neuropathy or peripheral artery disease: Given the patient's age and the fact that he has not had a physical in 3 years, conditions like diabetic neuropathy or peripheral artery disease could be underlying causes of his pain and should be considered, especially if other risk factors are present.

• Rare Diagnoses

  • Toe fracture: A fracture could occur from trauma during exercise, but the patient does not report a specific traumatic event, making this less likely.
  • Neuroma: A neuroma, such as a Morton's neuroma, could cause toe pain but typically presents with pain between the toes rather than in the great toe.
  • Infection (e.g., paronychia, cellulitis): While the patient denies signs of infection, these conditions could develop, especially if the ingrown toenail or blister becomes infected.