Differential Diagnosis for Bilateral Foot Pain

The patient's symptoms of bilateral foot pain, worsening with walking, and pain located below the heels and on top of the foot, suggest several possible diagnoses. Here is a categorized differential diagnosis:

• Single Most Likely Diagnosis

  • Plantar Fasciitis: This condition is characterized by pain in the heel and bottom of the foot, often worsening with walking and improving with rest. The patient's description of pain below the heels and the exacerbation of symptoms with walking align with plantar fasciitis, making it the most likely diagnosis.

• Other Likely Diagnoses

  • Overuse or Repetitive Strain Injury: Given the patient's age and the gradual onset of pain, an overuse injury from repetitive activities such as running or jumping is possible. This could affect the muscles, tendons, or bones on the top and bottom of the foot.
  • Morton's Neuroma: This condition involves a thickening of the tissue around the nerves leading to the toes, causing pain in the ball of the foot. While it typically affects one foot, it's conceivable for it to occur bilaterally, especially if the patient has a gait abnormality or wears poorly fitting shoes.
  • Stress Fractures: Although the patient denies any injury, stress fractures from overuse could be a consideration, especially if the patient has recently increased physical activity. These fractures can cause pain on the top or bottom of the foot that worsens with weight-bearing activities.

• Do Not Miss Diagnoses

  • Osteomyelitis or Septic Arthritis: Infection within the bone or joint can cause severe, persistent pain and is a medical emergency. While less likely given the gradual onset and lack of systemic symptoms, it's crucial not to miss these diagnoses due to their potential for serious complications.
  • Neoplastic Processes: Although rare, tumors such as osteoid osteoma or Ewing's sarcoma can cause persistent, worsening pain. These conditions are more likely to be considered if initial treatments fail and the pain persists or worsens over time.

• Rare Diagnoses

  • Tarsal Tunnel Syndrome: Similar to carpal tunnel syndrome but affecting the foot, this condition involves compression of the posterior tibial nerve, causing pain, numbness, and tingling in the foot.
  • Freiberg's Disease: A rare condition characterized by avascular necrosis of the metatarsal heads, leading to pain in the ball of the foot. It's more common in adolescents and young adults.
  • Charcot Foot: A condition associated with diabetes and neuropathy, characterized by a gradual destruction of the foot's bones, joints, and soft tissues, leading to deformity and pain. Given the patient's age and lack of mention of diabetes, this is less likely but should be considered if other diagnoses are ruled out and the patient has an undiagnosed neuropathy.

Treatment will depend on the confirmed diagnosis but may include rest, ice, stretching exercises, orthotics, physical therapy, and in some cases, medication or surgical intervention. A thorough examination, potentially including imaging studies, is necessary to determine the underlying cause of the patient's symptoms.