Final answer:
De Quervain tenosynovitis involves the abductor pollicis longus and extensor pollicis brevis muscles, related to the movement of the thumb. It is characterized by pain on the thumb side of the wrist, often exacerbated by repeated thumb movements or overuse.
Step-by-step explanation:
De Quervain tenosynovitis is a condition that affects the tendons on the thumb side of the wrist. The muscles involved in this condition are primarily linked to two specific tendons: the abductor pollicis longus and the extensor pollicis brevis. These muscles are responsible for movements such as abduction of the thumb and extension of the thumb at its first joint. Neither the flexor muscles nor the other extensor muscles listed are directly involved in De Quervain tenosynovitis.
The abductor pollicis longus muscle helps to move the thumb away from the palm, while the extensor pollicis brevis aids in straightening the thumb. This condition arises from irritation or inflammation of these tendons, commonly due to repetitive movements or overuse, leading to pain and tenderness around the base of the thumb.
The mentioned muscles like the extensor carpi radialis, flexor digitorum longus, or the palmar interossei muscles are not directly associated with De Quervain tenosynovitis, though they have functions in the movement and flexion of other fingers and the wrist. Symptoms of this condition are often exacerbated by movements that strain the affected tendons, such as grasping or pinching objects.
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