Differential Diagnosis for Stiff Shoulder Extension after Fall

• Single most likely diagnosis
  • Adhesive capsulitis (Frozen Shoulder): This condition is characterized by stiffness and pain in the shoulder joint, which can be exacerbated by a fall. The mechanism of injury from a fall can lead to inflammation and subsequent scarring of the shoulder joint, resulting in limited mobility.
• Other Likely diagnoses
  • Rotator cuff strain or tear: A fall can cause direct trauma to the rotator cuff muscles or tendons, leading to strain or tears. This would result in pain and stiffness, especially with extension of the shoulder.
  • Shoulder impingement syndrome: This condition occurs when the tendons of the rotator cuff muscles become inflamed or irritated, often due to repetitive motion or direct trauma like a fall. It can cause pain and stiffness in the shoulder, particularly with certain movements.
  • Fracture (e.g., proximal humerus, scapula): Although less common, a fall can result in a fracture around the shoulder joint. This would cause significant pain and stiffness, including limited extension.
• Do Not Miss diagnoses
  • Septic arthritis: Although less likely, septic arthritis is a serious condition that requires prompt diagnosis and treatment. A fall could potentially introduce bacteria into the joint, leading to infection. Symptoms would include severe pain, stiffness, and possibly fever.
  • Brachial plexus injury: A fall can cause a stretch or tear in the brachial plexus, a network of nerves that conducts signals from the spinal cord to the shoulder and arm. This would result in numbness, weakness, and potentially severe pain.
• Rare diagnoses
  • Osteonecrosis of the humeral head: This condition involves the death of bone tissue due to a lack of blood supply. A fall could potentially disrupt the blood supply to the humeral head, leading to osteonecrosis. However, this is a rare complication.
  • Complex regional pain syndrome (CRPS): This is a rare condition characterized by chronic pain, inflammation, and hypersensitivity after an injury, which in this case could be a fall. It's less directly related to the mechanical aspects of a stiff shoulder but could be a consideration in complex cases.