Featuring Dr. Bertrand Perey, MD, Orthopaedics Video Title: What is Thumb Arthritis and How is it Caused Duration: 2 minutes, 5 seconds

Arthritis at the base of the thumb is premature wear of cartilage between the thumb metacarpal and a bone in the wrist called the trapezium.

To illustrate this better, in my hand here is arthritis between the thumb metacarpal and trapezium, which is a bone at the bottom of the thumb metacarpal.

It’s premature wear of the cartilage, and patients usually experience pain right in this region, at the base of the thumb in the area called the thenar eminence, or they can experience pain in the back of the thumb in this general area here. They may feel it on the thumb side of their wrist.

And it’s often aggravated with pinching activities. The classic one is opening jars. A lot of patients find that they can’t open up a tight jar anymore; they can’t squeeze a towel. Some patients, if it’s bad enough, they can’t pinch their car keys to start the ignition.

So pain is a presenting symptom in the vast majority of patients. Pain can be activity-related, or some patients can have pain at rest, depending on how severe the arthritis is.

The cause of arthritis at the base of the thumb is somewhat unknown. By and large we call this idiopathic; there’s no known specific cause for the vast majority of them. They get it, it’s hereditary, or it can be related just at the way their anatomy is built.

It usually starts off with what we think to be instability, so the joints are shearing against each other in an abnormal way during their lifespan, and later on in life the cartilage wears prematurely.

Most patients who get this are in their 50s and 60s, although it can happen in the 40s and it can happen in the 70s. The majority of patients who get this are women, and the reason we think that is because women generally have more instability in their joints than men do, and this may be an accelerating factor for their symptoms.

If you think you may have arthritis at the base of the thumb, you should seek attention from your family physician. Your doctor can then direct you to the most appropriate person for management of your problem.

Presenter: Dr. Bertrand Perey, Orthopaedic Surgeon, New Westminster, BC

Local Practitioners: Orthopaedic Surgeon