Also called rizarthrosis
Rizarthrosis is osteoarthritis of the base of the thumb, also called the trapeziometacarpal joint, located between the trapezium and the first metacarpal bone. This joint plays a crucial role in gripping and in the pinch grip.
Degeneration of the joint cartilage leads to pain at the base of the thumb, especially during activities such as pinching, opening jars, or turning keys. Swelling, reduced strength, and sometimes a visible deformity of the joint may also occur.
The diagnosis is usually made based on clinical examination. An X-ray of the thumb can confirm the presence and severity of the osteoarthritis.
Non-surgical
Initial treatment consists of conservative measures such as pain medication, wearing a thumb splint or brace, and possibly a cortisone injection into the joint to temporarily reduce pain.
Surgical
When symptoms persist despite conservative treatment, surgery may be considered. Depending on the degree of joint degeneration, either a trapeziectomy (removal of the trapezium) or thumb basal joint prosthesis surgery (arthroplasty) can be performed.
The latter technique has evolved significantly in recent years and now provides very good long-term results.
After surgery, a period of immobilization and rehabilitation is required. Recovery of strength and function is generally faster after arthroplasty, while recovery after trapeziectomy may take several months.
