Basal Thumb Arthritis Info
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Video transcript
Basal thumb arthritis affects the small joint at the base of the thumb, where it meets the wrist. As the smooth cartilage wears away, this joint becomes painful, especially with pinching and gripping. Everyday tasks like opening jars, turning keys, and twisting lids can become sore and weak. The base of the thumb may ache after use, and over time can look a little more squared-off. It is a common form of arthritis, particularly later in life. Many people manage well for a long time without surgery. A supportive splint rests the joint, and can take the strain out of painful activities. Anti-inflammatory medication, and a cortisone injection into the joint, can give good relief. A hand therapist can show you ways to protect the thumb and keep it working. When these measures are no longer enough, an operation can help. There are two main operations for a worn-out thumb joint. The long-established option is a trapeziectomy, where the small arthritic bone at the base of the thumb is removed, so the painful surfaces no longer rub together. A newer option is a joint replacement, known as a Touch arthroplasty, where the worn joint is replaced with a small ball-and-socket implant, much like a miniature hip replacement, that lets the thumb move and pinch again. Both are done through a small incision at the base of the thumb, and aim to relieve the pain while keeping the thumb working. You go home the same day, with the thumb supported. A hand therapist guides your recovery, which is an important part of a good result. The thumb is protected at first, then eased back into movement as it heals. One reason a joint replacement may be chosen is that movement and strength often return sooner than after a trapeziectomy. Most people are back to light daily tasks over the first few weeks, with pinch and grip building up over the following months. As it settles, the goal is a comfortable thumb, that lets you get back to what you enjoy.
Basal thumb arthritis — causes, symptoms, non-surgical options, and when surgery might help.
What you're feeling
You likely feel pain at the base of your thumb where it meets your wrist. This is wear-and-tear arthritis in your carpometacarpal joint. The pain often flares after you use your hand or when you wake up in the morning. You might notice that gripping a jar or pinching a key makes the ache sharp and sudden.
Daily tasks can become difficult as the joint weakens. You may struggle to reach behind your back to fasten a bra or tuck in a shirt. Simple actions like turning a doorknob or lifting a heavy pot can trigger discomfort. If you have early disease, your thumb might slip out of place when you flex it or pinch something hard.
Many people find that rest helps, but the pain returns with activity. You might also feel stiffness or swelling in the area. Your surgeon will check for other hand issues before planning your care. While some treatments like steroid injections do not change your long-term results, they may help manage symptoms temporarily. Understanding these feelings helps you and your surgeon decide on the best path forward.
What's actually happening
In your thumb, the joint at the base is shaped like a saddle. It allows you to pinch and grip. In basal thumb arthritis, the smooth coating on the bone ends wears away. This wear-and-tear arthritis causes the joint to become unstable. The bones may shift out of place, especially when you pinch or jar your hand. This shifting is called subluxation.
The muscles and ligaments that usually hold this joint steady may weaken. When these stabilizers fail, the thumb bone moves upward instead of staying in its normal spot. This altered movement creates uneven stress on the joint. Over time, this stress damages the joint further and causes pain. Your surgeon sees this misalignment when examining your hand.
To fix this, your surgeon may remove a small bone to create space, or replace the joint with an implant. Some procedures use a tendon graft to support the thumb. Others use a wire to hold the bone in place for 6 weeks while it heals. The goal is to stop the bone from rubbing against bone and to restore a smooth, pain-free motion.
What we can do about it
You can start with self-management and hand therapy. Multiple therapy programs exist to help you after surgery, but they also guide you before it. A home-based video-assisted therapy program works just as well as in-person hand therapy for your upper extremity function. Your therapist uses their clinical expertise to assess your needs and treat your wear-and-tear arthritis. If you try hand therapy first, you may wait longer before needing surgery. However, patients who skip this treatment often have higher surgery rates within two years.
Medical management focuses on pain relief and reducing inflammation. You might use analgesic drugs, which are used more before joint replacement but less after. Your surgeon may offer a steroid injection into the joint. This does not change your major complication rates or your long-term function after surgery. For younger patients with early-stage arthritis, a bone surgery called a Wilson osteotomy may be a reasonable alternative to joint replacement. This procedure alters abnormal stress patterns to create a more uniform distribution across the joint.
Surgery is considered when conservative care reaches its limit and pain persists. Your surgeon may recommend removing the worn bone (resection arthroplasty) or replacing the joint with an implant. These options aim to relieve pain and restore movement. If a previous implant fails, other procedures like scaphometacarpal arthroplasty can serve as a reliable medium-term solution. New technologies like 3D printed braces show promise, but they are not yet proven superior to standard treatments.
When to see someone
See your GP if you have persistent pain that does not improve with rest. Ask for a specialist review if you notice weakness or instability in your thumb. You should also seek help if your thumb locks or gives way during movement. Contact your surgeon if symptoms interfere with your sleep or work. Seek immediate care if you experience a sudden worsening of pain. Your surgeon will check for signs like dorsal subluxation, where the first metacarpal moves out of place during thumb flexion. A complete hand examination is needed to rule out other symptomatic disorders before planning any treatment.
