Differential Diagnosis for Pain with Supination of the Forearm Against Resistance with Elbow Flexed

• Single Most Likely Diagnosis
  • Bicipital Tendinitis: This condition is characterized by inflammation of the biceps tendon, which can cause pain when the forearm is supinated against resistance, especially with the elbow flexed. The biceps muscle plays a significant role in supination, and its tendon runs through the shoulder and elbow, making it susceptible to strain and inflammation in these movements.
• Other Likely Diagnoses
  • Radial Head Fracture: Although more commonly associated with direct trauma, a radial head fracture can cause pain during supination, especially if the fracture involves the articular surface or if there is associated soft tissue injury.
  • Lateral Epicondylitis (Tennis Elbow): While primarily associated with wrist extension, lateral epicondylitis can sometimes cause pain with resisted supination due to the involvement of the extensor muscles of the forearm, which also assist in supination.
  • Intersection Syndrome: This condition involves inflammation of the tendons where the extensor pollicis brevis and abductor pollicis longus muscles cross over the extensor carpi radialis brevis muscle. It can cause pain with activities involving wrist and thumb movement, including supination.
• Do Not Miss Diagnoses
  • Radial Nerve Compression or Injury: Compression or injury to the radial nerve can cause significant morbidity, including weakness and numbness in the hand and wrist. While less common, it's crucial to consider this diagnosis, especially if there are symptoms of nerve compression such as numbness, tingling, or weakness.
  • Osteonecrosis of the Radial Head: A rare condition that can cause pain with movement of the elbow and forearm, including supination. Early diagnosis is crucial to prevent further damage.
• Rare Diagnoses
  • Synovial Chondromatosis of the Radiocapitellar Joint: A rare condition characterized by the formation of cartilaginous nodules within the joint, which can cause pain and mechanical symptoms, including locking or catching sensations during movement.
  • Tumors of the Forearm or Elbow: Although extremely rare, tumors such as osteochondromas or other benign and malignant tumors can cause pain and mechanical symptoms, including pain with specific movements like supination.