I have been having very painful thumbs for months now. It hurts when I press underneath the base of the tip of my thumbs (right where it bends). I have trouble picking things up with my thumb and fingers pinched together -- just hurts like the dickens. How can I figure out what's wrong and what to do about it?
You may be experiencing a problem known as sesamoiditis. But to know for sure (and to find out the best way to treat whatever is wrong), you will need an evaluation by your primary care physician or an orthopedic physician. Sesamoiditis refers to an inflammatory process affecting the sesamoid bones of the thumb. The sesamoid bones are two pea-sized bones embedded in the volar plate of the thumb. The volar plate is actually a very thick ligament that prevents hyperextension of the joint. The volar plate also reinforces the joint capsule and gives the joint greater stability. Even though they are small in size, the sesamoids play an important role in how the thumb moves. These tiny bones are part of the pulley system that allows for thumb movement. Two different tendons (adductor pollicis, flexor pollicis brevis) insert into each of these little bones. Together, these tendons across the sesamoid bones pull to create thumb adduction (moving the thumb toward the hand) and thumb flexion (bending the tip of the thumb). The sesamoid bones lift the tendons and their attached muscles away from the joint to increase the mechanical advantage needed for smooth thumb motion. If the sesamoids are injured or starting to degenerate, they can be a source of severe pain and disability. Normally, as the thumb bends, the sesamoid bones "track" or move up and down against the head of the thumb metacarpal (bone that forms the tip of the thumb). If the sesamoids do not track evenly on the center of the metacarpal head, the cartilage starts to wear unevenly and break down. That's when inflammation develops around the sesamoid bones with eventual bone-on-bone pain from chronic sesamoiditis. The physician will take your history and ask about current signs and symptoms. Sesamoiditis may be caused by previous trauma to the thumb but it can also be caused by wear and tear (more of a degenerative process). He or she will perform some clinical tests to evaluate the joints, tendons, ligaments, muscles, and other soft tissue structures. A positive sesamoid provocation test (SPT) will confirm if it is sesamoiditis. This test is done in two steps. First, the examiner holds the thumb in a flexed position and applies resistance to the patient's effort to bend the tip of the thumb. Then the thumb is held in an extended position and resistance is applied to the tip of the thumb again. A positive test for sesamoiditis is no pain with the first test and much more pain when the second test is done. This test is helpful because most of the time, X-rays are normal. Once a proper diagnosis has been made, then the appropriate treatment can be prescribed. Most of the time, this is a nonoperative (conservative) approach. Over-the-counter pain relievers, splinting, and physical therapy are the most cormmon treatments for thumb problems like you are describing. Occasionally, steroid injections are needed and more rarely surgery may be advised. But don't put it off because the earler problems are addressed, the more likely simple measures will take care of the symptoms.