Differential Diagnosis for Foot Pain that Worsens with Movement without Known Injury

Single Most Likely Diagnosis

• Plantar Fasciitis: This condition is characterized by inflammation of the plantar fascia, leading to pain in the heel and bottom of the foot. It is a common cause of foot pain that worsens with movement, especially after periods of rest. The lack of a known injury does not rule out plantar fasciitis, as it can be caused by repetitive strain or poor foot mechanics.

Other Likely Diagnoses

• Overuse or Repetitive Strain Injuries: Conditions such as Achilles tendinitis, peroneal tendinitis, or stress fractures can cause foot pain that worsens with movement. These are common in individuals who have recently increased their physical activity or have altered their gait.
• Morton's Neuroma: This condition involves a thickening of the tissue around one of the nerves leading to the toes, causing pain in the ball of the foot. It can be exacerbated by movement, especially if the individual wears tight or poorly fitting shoes.
• Bursitis: Inflammation of the bursae (fluid-filled sacs that cushion bones, tendons, and muscles near joints) in the foot can cause pain that worsens with movement.

Do Not Miss Diagnoses

• Deep Vein Thrombosis (DVT): Although less common, DVT can cause foot pain, especially if the clot is located in the deep veins of the lower leg or foot. It is crucial to consider DVT due to its potential for severe complications, such as pulmonary embolism.
• Osteomyelitis or Septic Arthritis: Infections of the bone or joint can cause severe pain that worsens with movement. These conditions are medical emergencies and require prompt diagnosis and treatment.
• Compartment Syndrome: This is a condition where pressure within the muscles builds to dangerous levels, decreasing blood flow. It can cause severe pain, especially with movement, and is a medical emergency.

Rare Diagnoses

• Tarsal Tunnel Syndrome: Similar to carpal tunnel syndrome but affecting the foot, this condition involves compression of the posterior tibial nerve as it travels through the tarsal tunnel on the inner side of the ankle. It can cause pain, numbness, and tingling in the foot.
• Erythromelalgia: A rare disorder characterized by burning pain, heat, and redness in the hands and feet, which can be exacerbated by movement or heat.
• Gout or Pseudogout: Although more commonly associated with sudden onset of intense pain in a single joint, these conditions can cause chronic pain that worsens with movement if not properly managed.