Basal joint arthritis is the result of the wearing away of cartilage in the joint at the base of the thumb. That’s why it is also known as thumb arthritis. The basal joint allows your thumb to move around so you can perform small motor tasks. Without plenty of cushioning cartilage, the joints become rough and grind over each other when you move, causing more joint damage. According to the Mayo Clinic, thumb arthritis is the most common form of osteoarthritis (wear and tear arthritis) of the hand. It can also be caused by injury to the thumb.
Hand pain and stiffness
Usually, the first sign of arthritis in the thumb is pain, tenderness, and stiffness. You’re most likely to feel it at the base of your thumb as you try to grip, pinch, or clasp something between the thumb and index fingers. You might also feel a pain when you try to apply mild force, such as when you twist a key in a lock, turn a door handle, or snap your fingers. You might be left with a lingering ache. A high level of pain doesn’t always mean your arthritis is more severe.
Decreased strength and range of motion
Over time, pain and inflammation can rob your hand of strength and restrict your range of motion. These restrictions become especially obvious when you try to pinch something or clasp an object tightly. You might find it increasingly difficult to open jars, hold a drink, or use buttons, zippers, and snaps. For those with a severe case of arthritis in the thumb, small motor tasks that were once a matter of routine become too painful to attempt, or almost impossible to accomplish without assistance.
The thumb may appear swollen, especially at its base, and you may develop a bony bump. Overall, the base of the thumb can take on an enlarged appearance. One alarming sign of thumb arthritis is improper alignment of the joint as it shifts from its normal positioning. This may affect the joint above the base as well, creating a bent-back appearance (hyperextension). In particularly severe cases, the thumb cannot get out of the palm of the hand.
Try to avoid clenching your hands when you carry things, as this can aggravate symptoms. You should also avoid repetitive movements that involve pinching or twisting. Apply alternating heat and cold to relieve inflammation and pain. A physical or occupational therapist can teach you how to perform range of motion exercises to improve function.
To help out around the house, take advantage of assistive devices designed to make it easier to write, open jars, grasp objects, and open doors.
Try an over-the-counter pain reliever or anti-inflammatory medication. If they don’t help, ask your doctor if there is a stronger prescription medication that may work. Your doctor may recommend corticosteroids, which are usually injected directly into the affected joint. Corticosteroids can relieve pain and reduce inflammation for a longer period of time than some other medications.
A splint can provide temporary support for your thumb and wrist, limiting movement so your joints can rest. The added support may ease pain for a while. It can also help with training your joints back into the correct position. You can wear a splint whenever you feel the need throughout the day, or even while you sleep. Check with your doctor or physical therapist to make sure you’re using the splint correctly.
If nothing else works, there are some surgical procedures that may help. A surgeon can fuse the bones of your joint together. This will decrease pain, but leaves you without flexibility. The bones can be cut and repositioned, or one of the bones in your thumb joint (trapezium) can be removed. A surgeon can also remove most of the joint, replacing it with a graft from other tendons. Surgery can be accomplished on an outpatient basis, but it takes time to regain strength and range of motion. If it gets to this stage, be sure to discuss the options carefully with your doctor.
Responding to early symptoms with splinting and medications will usually help relieve pain in the base of the thumb. However, basal joint arthritis will often worsen over time. Surgery may be the only option for pain relief once symptoms don’t respond to other treatments. Many people experience pain relief and recovery of range of motion once they have surgery.