What is a trigger thumb? A trigger thumb gets its name from the jump or "trigger" when a child tries to straighten his thumb. The affected thumb is in a "locked' or bent position. The tendon that moves the joint of the affected thumb tip becomes thick and develops a "bump" (called Notta's nodule). This" bump" does not allow normal tendon gliding inside the tendon sheath. Trigger thumb is common in young children and can be treated successfully with a surgical operation.
Some anatomical considerations.: A tendon is like a strong cord that connects the muscle to the bone. Inside the thumb, there is a tunnel in which the tendon glides. This tunnel is called the tendon sheath. There are tight spots in the sheath called "pulleys" which keep the tendon in position near the bone. The tendon must slide up and down inside the tendon sheath for normal movement of the thumb joint to occur. If the…
