Thumb Osteoarthritis – symptoms, diagnosis and treatment

Osteoarthritis of the thumb (also known as carpometacarpal joint osteoarthritis) is a common form of hand osteoarthritis. The carpometacarpal joint is located at the base of the thumb, where the thumb meets the wrist.

Symptoms of thumb osteoarthritis

Common symptoms of thumb osteoarthritis are pain and stiffness in the base of the thumb. It often becomes difficult to perform daily activities that require gripping or pinching, such as turning a key and opening cans and jars.

The most common symptoms of thumb osteoarthritis include:

  • Pain in the base of the thumb
  • Tenderness
  • Thumb stiffness
  • Swelling
  • Reduced grip and pinch strength
  • Grinding sensation in the thumb (late stages of the disease)
  • Bony lumps on the thumb

If you experience any of these symptoms you should schedule an appointment with a physical therapist, an occupational therapist or a doctor to get a diagnosis. 

Several risk factors play a part

There is no single cause for the development of thumb osteoarthritis and several risk factors tend to contribute. Main risk factors for thumb osteoarthritis are age, female sex, genetics and obesity. Onset of thumb osteoarthritis is most common in postmenopausal women. 

Other risk factors for thumb osteoarthritis include previous injuries to the thumb (fractures, sprains, ligament damage) , extreme sports that require a lot of hand strength (for example, rock climbing) and jobs that require repetitive hand movements (for example, hairdressing or massaging).

How osteoarthritis of the thumb is diagnosed

Traditionally, osteoarthritis was diagnosed by using an X-ray. Today, it is still a widespread belief that this method is necessary for diagnosis. However, according to the World Health Organization and extensive international research, osteoarthritis should be diagnosed by a healthcare professional through an assessment based on the patient’s medical history, joint function and pain level. 

The healthcare professional will also take risk factors for osteoarthritis into account and keep them in mind when establishing the diagnosis. If you experience pain or stiffness in your thumb and suspect that you may have osteoarthritis, a good first step is to contact your primary healthcare center and schedule to receive the right diagnosis.

Treating osteoarthritis of the thumb

First-line treatment for thumb osteoarthritis is patient education (learning more about the disease) often in combination with individualized exercises for the thumb. These individualized exercises should be coordinated by a physical therapist or an occupational therapist, either physically or digitally. Physical therapists and occupational therapists can also provide practical advice on how to more easily perform daily activities with the use of adapted equipment and braces or splints. 

There are several adaptive equipment tools that make life easier for someone living with osteoarthritis of the thumb. Such tools include adaptive jar and can openers, tube squeezers and scissors. A thumb brace or a wrist splint may provide symptom relief for some patients. 

Exercises for the base of the thumb should consistently be adapted to the patient’s abilities based on pain and function level. Individualized exercises can help ease pain, increase grip and pinch strength and improve range of motion.  As a complement to first-line treatment, if the pain becomes unbearable, non-prescription painkillers may be used for short periods of time. You should however always discuss the use of painkillers with your doctor to avoid side effects and drug interaction.

Other treatment methods

If first-line treatment doesn’t provide satisfactory symptom relief, other treatment methods may be necessary. 

On occasion, cortisone injections are used as a complement to treat severe osteoarthritis of the base of the thumb. These injections only offer short-term symptom relief and should be administered by an experienced orthopedic specialist. Cortisone injections should be used with caution as excessive injections may further damage the joint. 

Surgery can provide good results for many patients, although no surgery is risk-free. With surgery comes the risk of developing blood clots and infections. The most commonly performed operation for osteoarthritis of the base of the thumb is a trapeziectomy. During this procedure the trapezium (a small wrist bone in the base of the thumb) is removed. Less common surgical methods are joint fusion and joint replacement surgery. Most thumb operations are performed under local anesthesia. 

Read more about osteoarthritis of the fingers.