Differential Diagnosis for Partial Achilles Tear in the Muscle Belly

• Single most likely diagnosis
  • Achilles tendinosis or partial rupture: This is the most likely diagnosis given the location and description of the injury. The Achilles tendon is prone to overuse injuries, and partial tears can occur in the muscle belly or the tendon itself.
• Other Likely diagnoses
  • Calf strain: A strain of the gastrocnemius or soleus muscles can present with similar symptoms, including pain and swelling in the calf region.
  • Muscle hernia: A muscle hernia occurs when a portion of the muscle protrudes through a fascial defect, which can cause pain and swelling in the affected area.
  • Deep vein thrombosis (DVT): While less common, DVT can present with calf pain and swelling, and should be considered in the differential diagnosis, especially if there are risk factors such as recent travel or immobilization.
• Do Not Miss diagnoses
  • Ruptured Baker's cyst: A ruptured Baker's cyst can cause severe calf pain and swelling, and can be mistaken for a DVT or other conditions.
  • Popliteal artery aneurysm: A popliteal artery aneurysm is a rare but potentially life-threatening condition that can cause calf pain and swelling, and should be considered in the differential diagnosis.
  • Compartment syndrome: Compartment syndrome is a medical emergency that can cause severe pain, swelling, and numbness in the affected limb, and should be considered in the differential diagnosis, especially if there is a history of trauma.
• Rare diagnoses
  • Soft tissue sarcoma: A soft tissue sarcoma is a rare but potentially life-threatening condition that can cause a mass or swelling in the calf region.
  • Peripheral nerve sheath tumor: A peripheral nerve sheath tumor is a rare condition that can cause a mass or swelling in the calf region, and can be mistaken for other conditions such as a cyst or hematoma.