When it comes to repetitive stress injury, it involves damage to the joints which results to pain and diminished ability to carry out daily tasks. The small-sized joints in the thumb are highly susceptible to a repetitive stress injury. Certain activities that entail monotonous movements of the thumb or using hand tools can lead to these injuries.
Conditions due to repetitive stress injury on the thumb
Trigger thumb is a condition that causes catching or popping of the tendon that bends the thumb as it slides via the sheath. The repetitive use of the tendon can result to inflammation and swelling of the tendon sheath, eventually limiting the gliding movement of the tendon. In severe cases, the thumb can end up locked in a bent position.
Activities that entail repetitive gripping such as extensive use of hand tools can lead to trigger thumb. The condition can be pain-free or trigger pain on the palm side of the base of the thumb. In most cases, the condition gets better with adequate rest. Splints are oftentimes used to prevent movement of the thumb for up to 6 weeks or longer until the symptoms improve.
Basal joint arthritis
Arthritis involves the breakdown of cartilage or padding in between the bones in a particular joint. The joint at the bottom part of the thumb is quite susceptible to arthritis. Even though minimal arthritic changes often develop with advancing age, repetitive stress on the thumb with undertakings that entail heavy-duty pinching can lead to early wear and tear on the joint.
De Quervain disease
This condition is due to overuse of the tendons responsible for moving the thumb away from the hand and into a hitch-hiking position. It is important to note that the pain often occurs throughout the rear part of the thumb and down into the thumb side of the wrist.
De Quervain disease is managed conservatively using splinting to reduce movement and anti-inflammatory medications such as aspirin, naproxen and ibuprofen. The doctor might even prescribe oral steroid medications such as prednisone.
The ligaments attach bone to bone to provide stability to the thumb joints. These structures are prone to injuries. Over time, the repetitive stress injury can cause the ligaments to overly stretch or even tear which makes the thumb less stable. This can significantly affect the overall pinch strength as well as make fine motor skills such as writing difficult. The ulnar collateral ligament is prone to repetitive stress injury. Long-lasting injury to this ligament due to repetitive stress injury is known as ‘gamekeeper’s thumb’.
When it comes to ‘gamekeeper’s thumb’, it is due to the constant force against the thumb, usually towards the thumb side of the wrist. The injury can be triggered by frequent participation in sports or activities that entail constant pinching between the thumb and index finger.