Thumb arthritis is the most common arthritis of the hand and wrist, affecting the joint at the base of the thumb – also known as the carpometacarpal or CMC joint. In many cases, people often ask about a cortisone injection in thumb joint. So, what is thumb arthritis, and when should you have a CMC joint injection?

What are the symptoms of thumb arthritis?

Thumb arthritis usually causes pain, swelling, and stiffness at the base of the thumb. Pain is worse when gripping, pinching, or grasping. People often find it difficult to perform simple tasks such as opening jars or turning doorknobs or keys. Also, other findings include restriction in movement of the thumb, decreased thumb strength, and a bony appearance at the base of the thumb.

Factors that can increase the risk of thumb arthritis include female sex, age over 50 years, previous injuries such as cracks or sprains, jobs that place high stress on the thumb, and obesity.

How do we diagnose thumb arthritis?

Often, we diagnose thumb arthritis using a combination of clinical tests and X-rays.

In general, clinical findings include tenderness at the base of the thumb, restricted movement of the thumb joint, and reduced thumb strength.

X-ray of the thumb shows narrowed joint space, spur formation, and a deformed joint.

Overall, it is essential to assess every patient with thumb pain to ensure no other cause such as De Quervain’s tenosynovitis, trigger thumb, or inflammatory arthritis.

What treatments are available for thumb arthritis?

Generally, most people respond well to simple treatments supervised by a hand therapist. These treatments include specific stretching and strengthening exercises for the thumb, wrist, and forearm. Sometimes, a hand therapist can try manual therapy techniques to improve thumb movement. For example, a thumb spica splint can help reduce pain by limiting the movement of the thumb while still allowing the use of the thumb.

Pain-relieving creams or gels such as ibuprofen or flexiseq can help with exercise therapy.

Should you have a cortisone injection in thumb joint? 

ultrasound-guided cortisone injection into thumb joint

In cases that fail to respond to simple treatments, steroid injection for basal thumb arthritis is the next step. In addition, you should consider a cortisone injection for your thumb when your pain is severe or your thumb arthritis stops you from performing simple activities such as dressing, cooking, or cleaning.

Recent evidence suggests ultrasound-guided injections for thumb arthritis are more accurate and effective than blind injections. Specifically for the CMC joint injection, ultrasound-guided injections are 94% accurate compared to 80% with blind injections. In addition, cortisone injections for the thumb provide good pain relief for up to 6 months.

What about gel injections for thumb arthritis? 

Some doctors think that gel injection is also helpful for thumb arthritis., although we need more evidence to support this view. Gel injections, or hyaluronic acid injections, are used for arthritis. However,  a recent paper suggests no favourites regarding 1st CMC joint injection. 

What about PRP injection for thumb arthritis? 

Platelet-rich plasma injections - alternative to cortisone injection in shoulder

Although a PRP injection has shown a good effect on knee arthritis, there is no evidence that PRP helps thumb arthritis. Nevertheless, we would consider a PRP injection for thumb arthritis in people who have failed other treatments, including a cortisone injection.

A recent study comparing PRP to cortisone or hyaluronic acid injections for thumb arthritis found no one injection superior. 

If a CMC joint injection is not effective, we would then consider a surgical procedure of fusion or bone excision.

Final word from Sportdoctorlondon about a cortisone injection in thumb joint

Thumb arthritis is a common condition associated with pain with simple activities and restriction in thumb movement. Simple treatments such as hand therapy and splints can help. An ultrasound-guided steroid injection for thumb arthritis can also assist. You should find a doctor with experience in injecting under ultrasound.

Other elbow and hand conditions:

Dr. Masci is a specialist sport doctor in London. 

He specialises in muscle, tendon and joint injuries.