Arthritis of the Thumb (Basilar Joint)

Arthritis of the thumb, also called Basilar joint arthritis because it effects the basilar joint of the thumb, is a common form of arthritis effecting the hand. A form of osteoarthritis, arthritis of the thumb effects the first carpometacarpal joint located near the wrist at the base of the thumb and is generally secondary to a previous injury or trauma to the joint.

The unique ability of the thumb to span across the palm and touch opposing fingers is both a characteristic that distinguishes human beings in the animal kingdom and a range of motion that joint creates vulnerability. The unique shapes of the small bones of the thumb permit this range of movement, with stability of the carpometacarpal joint dependant on several small ligaments that remain close to the joint surfaces while allowing movement. Loosening of these ligaments may result in excessive sliding of the joint surfaces and increase wear on the joint cartilage. This is a degenerative environment that will eventually lead to arthritis if untreated.

If joint degeneration continues to progress, inflammation may occur - resulting in pain when pressure is applied to the joint in pinching and grasping activities. In this environment, joint surfaces are eventually destroyed and bony spurs may develop around the joint. In severe cases, there may be complete joint destruction, an inward collapse of the metacarpal, and deterioration around the trapezium. Other joints may also become effected as they react to the changes.

Basilar joint arthritis will produce pain that progresses over time, eventually discouraging use of the thumb. This correspondingly results in joint weakness and muscle loss. Upon examination, there may be swelling at the base of the thumb as a result of joint inflammation.

Risk Factors
Arthritis of the Thumb more commonly effects women than men and generally occurs after the age of 40. It is most often the result of the same joint conditions prompting osteoarthritis of other joints - joint instability, cartilage deterioration and wear and tear. Many of these conditions are affiliated with common hand injuries and conditions discussed in this section, which, if treated early, can reverse or slow the progression of an environment within the joint that will eventually lead to arthritis of the thumb. A fracture or other traumatic injury can also lead to joint dysfunction and deterioration that can lead to arthritis of the thumb as well.

Diagnosis and Treatment
Following a thorough review of a patient's medical history and physical examination of the thumb, a series of imaging scans will determine joint damage, the severity of the degeneration and the rate of progression.

The best treatment for arthritis of the thumbs varies from patient to patient and is usually determined based on the severity of the condition and the state of the joint environment. If conservative treatment is indicated, it may entail the use of NSAIDs (nonsteroidal anti-inflammatory drugs), the refrain from activity causing stress to the effected area, corticosteroid injections, rehabilitation and occupational therapy. Splinting of the thumb may also be indicated in order to help support it and keep it in a rest position, which will reduce the pain and prevent deformity.

Advanced cases and arthritis may require ligament reconstruction tendon interposition (LRTI) arthroplasty, in order to remove the damaged surfaces within the joint and create a stronger joint. This will eliminate pain, improve hand strength and range of motion necessary for day-to-day activities. Total joint replacement may also be considered.