The wrist is a complex area made of many bones, joints, nerves, ligaments, tendons and blood vessels. The outer side of the wrist is the side containing the thumb. The main structures in this area are the radius bone that extends from the elbow to the wrist, the scaphoid and lunate carpal bones located deep within the wrist, the first metacarpal bone located between the carpal bones and the base of the thumb, and the radial and median nerves. Any of these structures can be the source of outer wrist pain. The main causes of pain on the outer side of the wrist are ligament damage, nerve entrapment, De Quervain tenosynovitis, fractures and arthritis.
The most common injury to the outer wrist is damage to the ligaments. Usually the ligaments are simply stretched, resulting in a mild sprain that heals relatively quickly. Ligament tears are more serious and can cause movement or dislocation of bones in the area, especially the lunate or radius bones. Gamekeeper’s thumb is a sprain or tear of the ligament at the base of the thumb. It often develops gradually, due to repeated thumb movements. The ligament can also be injured suddenly, such as by falling onto an outstretched thumb or falling while holding onto an upright ski pole.
Nerves can become entrapped in the wrist as they travel through narrow spaces. When inflammation and scar tissue are also present, they further reduce the size of the space and increase the likelihood of nerve entrapment. Wrist inflammation may occur with an acute injury or repeated wrist movements, such as when typing or writing. Carpal tunnel syndrome occurs when the median nerve is compressed within a tunnel formed by the carpal bones. An entrapped median nerve causes pain, tingling, numbness and weakness in the palm side of the outer wrist, the palm itself, the thumb and the first two and one-half fingers. Wartenberg syndrome occurs when a branch of the radial nerve becomes entrapped, producing pain, numbness and tingling on the back side of the outer wrist and the back side of the thumb.
De Quervain Tenosynovitis
De Quervain tenosynovitis refers to inflammation of the coverings, or sheaths, of two tendons that travel from the forearm to the thumb. These tendons are the abductor pollicis longus and extensor pollicis brevis tendons. The inflammation produces pain and swelling in the outer wrist and stiffness of the thumb. De Quervain tenosynovitis is typically caused by repetitive thumb movements, such as playing video games. It can also occur with an injury caused by athletic or recreational activities or during a fall.
Fractures and Avascular Necrosis
Any of the bones in the outer wrist can be broken, including the scaphoid, lunate, first metacarpal and radius bones. Wrist fractures are caused by trauma, especially during contact sports, such as ice hockey and boxing. They may also occur with motor vehicle accidents and falling onto an outstretched hand. Thin bones, or osteoporosis, increase the likelihood of developing a wrist fracture.
Avascular necrosis occurs when part of a bone dies due to inadequate blood supply. The scaphoid and lunate bones are particularly susceptible to avascular necrosis, especially following fractures. Avascular necrosis causes chronic pain in the area.
Joint inflammation, or arthritis, is a relatively common cause of wrist pain. In osteoarthritis, joints are damaged by repetitive “wear and tear” injuries to the joint surfaces. This type of arthritis often involves multiple joints in the body, especially as people get older. Younger people without generalized osteoarthritis may develop osteoarthritis of one or both wrists due to repeated wrist movements, frequent sprains or unhealed fractures or dislocated joints. Osteoarthritis typically causes an achy type of chronic pain, which may be accompanied by a grinding sound during wrist movements.
Other types of arthritis may also cause pain on the outer side of the wrist. Rheumatoid arthritis is an autoimmune disorder, which usually affects both wrists at the same time. Psoriatic arthritis is a disorder causing both psoriasis of the skin and inflammation of joints. Usually the skin rash occurs years before the onset of arthritis. Septic arthritis -- due to infection within a joint -- is another possible, but uncommon, cause of wrist pain.
See your doctor if you are unable to move your wrist or thumb or if your pain is severe or interferes with your usual activities. Also seek medical attention if you have a fever or rash with your wrist pain or if you have pain in multiple joints of your body.
Reviewed by: Mary D. Daley, MD
- American Family Physician: Evaluation and Diagnosis of Wrist Pain -- A Case-Based Approach
- American Family Physician: A Clinical Approach to Diagnosing Wrist Pain
- Wheeless' Textbook of Orthopaedics: Differential Diagnosis of Dorsal and Radial Sided Wrist Pain
- Current Reviews in Musculoskeletal Medicine: Scaphoid Fractures in the Athlete
- International Orthopaedics: Entrapment of the Superficial Branch of the Radial Nerve (Wartenberg's Syndrome) -- A Report of 52 Cases
- American Academy of Orthopaedic Surgeons -- OrthoInfo: De Quervain's Tendinosis