Lateral Epicondylitis (Tennis Elbow): This condition is characterized by pain on the lateral aspect of the elbow, which can be exacerbated by resisted supination, among other wrist and elbow movements. The pain is typically due to inflammation of the tendons that attach to the lateral epicondyle.

Radial Head Fracture: A fracture of the radial head can cause pain with movements that involve supination, especially if the fracture involves the articular surface.
Radial Tunnel Syndrome: This condition involves compression of the radial nerve and can cause pain in the back of the hand or the forearm, which may be worsened by resisted supination.
Elbow Strain or Sprain: Overuse or acute injury to the muscles and ligaments around the elbow can lead to pain with specific movements, including resisted supination.

Osteochondritis Dissecans of the Capitellum: A condition where a piece of cartilage and bone in the elbow joint becomes damaged, leading to pain and potentially locking or catching sensations. It's crucial to diagnose this condition to prevent further damage.
Infection (Septic Arthritis or Osteomyelitis): Although less common, infections around the elbow can cause significant pain with movement and require urgent medical attention to prevent serious complications.
Radial Nerve Injury: Direct injury to the radial nerve can cause pain, weakness, and sensory changes, and it's essential to identify and treat promptly to avoid long-term damage.

Ganglion Cyst: A lump under the skin that occurs near joints or tendons, which can cause pain if it compresses a nerve or restricts movement.
Synovial Chondromatosis: A rare condition where cartilage grows inside the joint, leading to pain, swelling, and decreased range of motion.
Elbow Tumors: Both benign and malignant tumors can occur around the elbow, causing pain and other symptoms, and are important to consider in the differential diagnosis, although they are rare.