The exact number of muscles primarily in the wrist is difficult to define precisely. Many forearm muscles have tendons that cross the wrist joint and contribute to its movement. However, the references provide information about muscles that significantly influence wrist action.
According to the reference, there are 6 main muscles that flex the wrist.
These are:
- Flexor carpi radialis
- Flexor carpi ulnaris
- Palmaris longus
These muscles originate on the humerus, cross the forearm, extend through the wrist via tendons, and insert into the bones of the hand. This shows that even though the muscle bodies are in the forearm, their tendons' action at the wrist is what defines them as wrist flexors.
It is important to note that other muscles with tendons crossing the wrist also contribute to its movements (flexion, extension, abduction, adduction). Therefore, while the reference mentions 6 key wrist flexors, the total number of muscles affecting wrist movement is higher.
