Base of Thumb Arthritis: When Everyday Tasks Become a Challenge

Opening a jar. Turning a key. Pinching a pen. These are actions most of us perform dozens of times a day without a second thought — until pain at the base of the thumb makes even the simplest task feel surprisingly difficult. Base of thumb arthritis is one of the most common forms of arthritis in the hand, and whilst it can be frustrating, there is a great deal that can be done to help.

What is base of thumb arthritis?

The joint at the base of the thumb — known medically as the carpometacarpal joint, or CMC joint — is a remarkable piece of engineering. Its saddle shape allows the thumb to move in multiple directions, giving us the precision grip that sets human hands apart. However, this mobility comes at a cost: the joint is under considerable load throughout daily life, making it particularly susceptible to wear and tear over time.

When the cartilage lining this joint breaks down, the bones begin to rub against one another, causing pain, stiffness, and inflammation. This is carpometacarpal arthritis — commonly called base of thumb arthritis or trapeziometacarpal arthritis.

Recognising the symptoms

The most telling sign is pain and tenderness at the base of the thumb, just above the wrist. Gripping, pinching, and twisting movements are typically the most provocative. Many patients notice the pain is worst first thing in the morning or after periods of rest, easing slightly once the joint is warmed up. Over time, some swelling or a bony prominence may develop at the joint, and in more advanced cases the thumb can develop a characteristic squared appearance at its base.

Who is affected and why?

Base of thumb arthritis is considerably more common in women than men and most frequently develops after the age of 50, though it can occur earlier. Hormonal factors, joint laxity, and a genetic predisposition all play a role. Previous injury to the thumb or wrist can also accelerate cartilage wear in the joint.

Treatment and management

The reassuring reality is that the majority of patients are managed very successfully without surgery. A hand therapist can provide a custom-fitted splint to support the joint during aggravating activities, alongside targeted exercises to strengthen the surrounding muscles — an approach shown to significantly reduce pain and improve function (Spaans et al., Journal of Hand Surgery, 2022).

Anti-inflammatory medications and activity modification are useful in the early stages. A corticosteroid injection into the CMC joint can provide meaningful relief when symptoms are more persistent, with evidence supporting its effectiveness as part of a broader management plan (Hamasaki et al., Journal of Hand Therapy, 2021).

For patients in whom conservative treatment has been fully explored without sufficient improvement, surgery offers excellent long-term outcomes. The most established procedure — trapeziectomy, in which the small wrist bone forming part of the joint is removed — has a strong evidence base and consistently high patient satisfaction (Bravo et al., Cochrane Database of Systematic Reviews, 2023).

A new frontier: CMC joint replacement

Recent years have seen a significant advance in the surgical management of base of thumb arthritis with the development of total CMC joint replacement. Much like a hip or knee replacement, these implants resurface the worn joint with precision-engineered components, restoring a smooth, pain-free surface whilst preserving the natural mechanics of the thumb. The key advantage over traditional surgery is recovery time — patients typically regain functional use of the hand considerably faster than with trapeziectomy, with many returning to normal activities within six to eight weeks. Early and medium-term results from clinical studies are highly promising, with excellent pain relief and patient-reported outcomes (Bouyer et al., Journal of Hand Surgery (European Volume), 2022). For appropriately selected patients — particularly those who are active and wish to return to work or sport as quickly as possible — CMC replacement represents an exciting and increasingly accessible option that is genuinely changing the conversation around thumb arthritis surgery.

Taking the next step

If thumb pain is affecting your quality of life, specialist assessment can make a real difference. Mr Jamie A'Court offers expert hand and upper limb consultations at Beaumont Hospital, providing a clear diagnosis and a treatment pathway tailored to your needs and lifestyle.

This article is intended for general information purposes only and does not constitute medical advice. It is not a substitute for a consultation with a qualified healthcare professional. If you are experiencing hand or thumb pain, please seek advice from your GP or a specialist.