Pain at the base of the thumb is very common. This can occasionally happen because of an accident or trauma sustained in younger life, but more commonly happens as the carpometacarpal (CMC) joint becomes more worn out with age. Sometimes the shape of the joint is altered as a person develops and this can contribute to arthritis in later life.
A major study from Derby and Nottingham1 demonstrated that 25% of postmenopausal ladies have quite significant osteoarthritis of this joint when they present for other reasons, but only 25% of them have pain. If you have arthritis of the thumb base, but no pain, then there’s no requirement to have any formal treatment, but hand therapy exercises can be helpful to keep the joint moving.
If you do develop pain from the base of your thumb, then in the first instance, most people will want to try a splint. There is a new splint design based on the PUSH CMC splint, or variants of this, which are designed to hold the joint in a sympathetic position, but still allow some daily activities to take place. These splints sometimes aren’t particularly comfortable when you start wearing them, but as time goes on, the plastic can mould to the shape of your hand and they can become much more comfortable. They can be worn during the day, or at night, or both to suit your individual needs.
If hand therapy exercises and splinting are not enough to control the pain, then we would normally talk to you about a steroid injection. This would be done either based on landmarks in the clinic, or more commonly using ultrasound to direct the needle directly into the joint and deliver the steroid. This is usually combined with some local anaesthetic. This can be associated with a steroid flare where the pain becomes worse for a couple of days prior to settling. In one in three patients, this can be really quite painful and paracetamol and simple painkillers would be advised. It would be ideal to combine this with a period in your life where your hands could be rested for a day or so afterwards.
Following the injection, the synovitis (inflammation in the lining of the joint) would be expected to settle over a two to four week period, and so the results won’t be immediate2. How long the steroid lasts is very variable from one person to another, but would usually be expected to help for at least three months, with six months being around average, and some patients getting several years of benefit. The goal here is generally to try and delay any form of surgical treatment for as long as possible, and so several injections can be delivered if they are benefiting an individual patient. The steroid does come with some risks including a small risk of thinning or bleaching the skin, which can be a problem in people with significant skin pigment. There is also a risk that the injection doesn’t help at all, and of course, they will be temporary in nature.
If injections fail to control the symptoms, or the pain-free period between injections is getting less and less common, then we would talk to you about surgical options. The gold standard treatment has historically always been trapeziectomy and that remains the case in 2025. Trapeziectomy is an operation where a cut is made in the skin, the blood vessels and nerves are protected, and the trapezium bone at the base of the thumb is removed. Following that, additional procedures for which there are a number of different techniques are usually conducted to try and prevent the thumb from falling down and impacting on the scaphoid bone, which would potentially lead to further pain. This is known as a ligament reconstruction or tendon interposition. After that the hand is placed in a protective splint and usually held there for six weeks or so. This is to allow some scar tissue to form in the gap. Following that the period of hand therapy is needed to get the movement to come back in the thumb, but there would normally always be a reduction in pinch strength compared with the non-operated side, or compared with normal control patients. This is often not noticed by people undergoing trapeziectomy because the thumb pinch has weakened as a result of the arthritis. This is a good operation in terms of long-term pain relief, but it can take six months before people are not thinking about their thumb on a daily basis.
A more recent technique has been the introduction of a thumb carpometacarpal joint replacement. There are two main designs commonly used in the UK, which are called the Touch and the MAIA. These roughly follow the geometry of a hip replacement and performed through a similar incision either across the front or the back of the thumb. A metal and high-grade surgical plastic joint is then inserted and the tension is checked on the operating table to make sure it is appropriate. The thumb would normally be protected with a bulky dressing or a splint for a couple of weeks after the surgery, following which hands can therapy exercises are advocated. The advantage of this procedure is a much more rapid return to full function, although at 12 months, the large data studies suggest that results are similar whether patients have undergone a trapeziectomy or a joint replacement. There are some prerequisites for performing a joint replacement, which we would discuss with you in the clinic, and there are some additional risks related to this being a metal implant. We now have 10-year data available that suggests that the survivorship is very good at 10 years and around 90% will still be in place, but this is not quite as good as the survivorship data for a hip replacement or a knee replacement. Additionally, these procedures are relatively new in terms of this latest generation of implants, and so we would talk to you in the clinic about monitoring in the long term. And this is our group’s practice to enter data for all patients undergoing this procedure on the British Hand Surgery Society website amplitude, which would then send you a questionnaire every six months to monitor how you’re getting on after the joint replacement.
Lastly, for younger manual labourers, a more durable option is sometimes preferred, and for these patients we would discuss carpometacarpal joint fusion (arthrodesis). This procedure would have the advantage of being a single operation for the joint without concern about lifting in the future. But there were some differences in the post-operative rehabilitation, and movement from the carpometacarpal joint would be lost. We would talk to you about the positions that it would be difficult to get your hand into again in the future.
In summary, there are lots of non-operative and operative options to help with the pain from thumb base arthritis. And we would happily speak to you about which one matches your individual needs where we meet in the clinic. Please contact Mr Rupert Wharton, Grosvenor Orthopaedic Partners Consultant Hand & Wrist Surgeon or you can read more about Thumb Artisitis here
References:-
1.Armstrong AL, Hunter JB, Davis TR. The prevalence of degenerative arthritis of the base of the thumb in post-menopausal women. J Hand Surg Br. 1994 Jun;19(3):340-1. doi: 10.1016/0266-7681(94)90085-x. PMID: 8077824.
2. Swindells MG, Logan AJ, Armstrong DJ, Chan P, Burke FD, Lindau TR. The benefit of radiologically-guided steroid injections for trapeziometacarpal osteoarthritis. Ann R Coll Surg Engl. 2010 Nov;92(8):680-4. doi: 10.1308/003588410X12699663905078. Epub 2010 Jul 19. PMID: 20659360; PMCID: PMC3229378.