Rhizarthrosis

Rhizarthrosis : definition

Rhizarthrosis is caused by the wearing down of the joint located at the base of the thumb between the first metacarpal bone and trapezium, which is a wrist bone.

It causes disabling pain at the base of the thumb with gradual hand function limitation and damage that can ultimately lead to the stage of a « Z-shaped » thumb deformity. Picking up objects between the thumb and the other fingers thus becomes almost impossible.
It particularly affects women from the age of 50. Early forms exist.

Treatment of rhizarthrosis

First-line therapy is treatment with prescription of anti-inflammatory medication, keeping the column of the thumb at rest by wearing specific splints, having mesotherapy sessions, corticoid injections …
If all else fails, surgical treatment can be recommended, it relies mainly on two techniques:
- « Trapeziectomy with ligamentoplasty » consists in completely removing the trapezium bone and stabilizing the base of the thumb by performing ligament reconstruction with tendon interposition. This remains a time proven procedure in terms of reduction of pain intensity and recovery of the hand function. It is also durable over time.
- « The trapeziometacarpal joint replacement » which consists in replacing the articulation of the base of the thumb by an artificial joint composed of two parts, one fixed in the metacarpal bone (stem) and one in the trapezium (cupula) similar to mini-THR.

Opting for one of these two techniques depends on the age, occupational activity, functional requirement, characteristics of the joint damage, of the patient’s wishes and the surgeon’s preferences.

After the procedure, an immobilization by a resin cuff is put in place for a 3 week-period whatever the technique. Recovery time is 4 months on an average for trapeziectomy and shorter in case of replacement.