Thumb arthritis

Thumb arthritis is osteoarthritis of the base of the thumb, i.e. wear of the cartilage between the trapezium and the base of the 1st metacarpal. The base of the thumb is subjected to considerable stress during daily activities (such as gripping, pinching or turning objects), which explains the progressive destruction of the cartilage.

Over time, the cartilage covering the joints thins out and there is direct contact between the bones, which is painful. In more advanced stages, bone spurs (osteophytes) may appear in the joint, causing the metacarpal to slide outwards (thumb deformity).

This pathology particularly affects women over the age of 40, but men can also develop painful osteoarthritis of the thumb. Treatment of rhizarthrosis varies according to the severity of symptoms, and can range from conservative measures to surgical interventions, such as thumb prosthesis or trapezectomy.

Symptoms of rhizarthrosis appear gradually and can vary in intensity. It’s important to recognize these signs as soon as they appear, in order to adapt the treatment of osteoarthritis of the thumb and limit its aggravation.

Here are the main symptoms to watch out for, so that appropriate treatment can be put in place quickly and the condition can be prevented from worsening:

• Pain and swelling at the base of the thumb
• Lack of strength to hold or grasp an object, open a bottle, turn a key, etc.
• Stiffening of the thumb and progressive “Z”-shaped deformation of the thumb in the palm.

When pain begins to interfere with daily activities, a visit to your hand surgeon is recommended.

Rhizarthrosis is most common in women over the age of 40, but can also affect men. Although the exact cause remains uncertain, the condition is generally the result of a combination of multiple factors. Hereditary factors, ligament hyperlaxity and a history of thumb fractures or lesions increase the risk of developing rhizarthrosis, as does repetitive stress on the thumb, often associated with intense professional or leisure activities.

Your hand surgeon can diagnose osteoarthritis of the thumb on clinical examination. X-rays are taken to determine the radiological stage of osteoarthritis, which is important when deciding on surgical treatment.

Treatment of rhizarthrosis depends on the stage of the disease and the symptoms experienced.
Several approaches can be considered, and combined if necessary :

• Rest, anti-inflammatories and ice on the thumb
• Resting splint at night and flexible support splint during the day
• Infiltrations of cortisone, hyaluronic acid or platelet concentrate can relieve pain for a few months, and may be repeated.
• Ergonomic exercises and adjustments
• Occupational therapy

When pain does not disappear, after conservative treatment, rhizarthrosis surgery may be proposed. The type of surgery depends on the patient’s age, type of manual activity and the radiological stage of osteoarthritis. Dr. Bejic is an expert in the management of rhizarthrosis and will recommend the optimum treatment, taking into account your personal needs and expectations.

In very early forms, it is possible to cut a strip of tendon at the base of the thumb to reduce pain, without compromising future surgery.

The damaged joint can be replaced by a dual-mobility titanium trapeziometacarpal prosthesis. Contraindications include painful osteoarthritis between the trapezium and the scaphoid, and a confirmed allergy to nickel. The prosthesis relieves pain and rapidly restores thumb mobility.

In cases where a prosthesis is not an option, a trapezectomy may be proposed. This involves removing the trapezium to create space and eliminate bone impingement at the base of the thumb, and stabilizing it with a local tendon.

Trapezectomy and prosthesis are highly effective operations for reducing pain, and usually enable good recovery of thumb mobility within 2 to 6 months.
Useful links :

• Information Sheet from the French Society for Hand Surgery
• Information Sheet – Trapeziometacarpal Prostheses in Thumb Osteoarthritis
• Touch Prosthesis