Lateral epicondylitis (tennis elbow): This is the most likely diagnosis due to the characteristic presentation of pain and tenderness on the lateral aspect of the elbow, often associated with activities that involve gripping or twisting motions.

Radial tunnel syndrome: This condition involves compression of the radial nerve and can present with similar symptoms to lateral epicondylitis, including pain and weakness in the forearm and wrist.
Elbow strain or sprain: Overuse or acute injury to the muscles and ligaments around the elbow can cause pain and inflammation, mimicking lateral epicondylitis.
Osteochondritis dissecans of the capitellum: This condition involves a fragment of cartilage and bone becoming detached from the capitellum, leading to pain and stiffness in the elbow.

Fracture of the radial head or neck: A fracture in this area can cause severe pain and limited mobility, and if missed, can lead to complications such as nonunion or malunion.
Infection (septic arthritis or osteomyelitis): Infection in the elbow joint or surrounding bone can cause severe pain, swelling, and redness, and if not promptly treated, can lead to serious complications.
Nerve entrapment (e.g., radial or posterior interosseous nerve): Compression of nerves around the elbow can cause pain, numbness, and weakness, and if not addressed, can lead to permanent nerve damage.

Tumors (e.g., osteoid osteoma, giant cell tumor): Although rare, tumors can occur in the elbow region and cause pain and limited mobility.
Rheumatologic conditions (e.g., rheumatoid arthritis, gout): These conditions can cause inflammation and pain in the elbow, although they are less common causes of lateral elbow pain.
Cubital tunnel syndrome: Compression of the ulnar nerve at the elbow can cause pain, numbness, and weakness, but is less common than other conditions on this list.