Question

What is the mechanical reason why grip strength is MOST LIKELY reduced when the wrist is flexed?

1) The finger flexors are actively insufficient and shortened as they pass over a flexed wrist.
2) The finger extensors are actively insufficient as they pass over an extended wrist.
3) The finger flexors are passively insufficient and shortened as they pass over a flexed wrist.
4) The finger extensors are passively insufficient as they pass over an extended wrist.

Answer 1

Grip strength is likely reduced when the wrist is flexed because the finger flexor muscles, primarily the flexor digitorum superficialis and profundus, are actively insufficient due to being shortened as they pass over the flexed wrist, limiting their force generation.

Step-by-step explanation:

The mechanical reason why grip strength is most likely reduced when the wrist is flexed is because the finger flexors are actively insufficient and shortened as they pass over a flexed wrist. The finger flexors in question include the flexor digitorum superficialis and flexor digitorum profundus, which are responsible for flexing the fingers and the hand at the wrist.

When the wrist is flexed, the space through which these tendons travel can become constricted, and the muscles are not able to generate as much force due to being at a mechanical disadvantage. The flexor retinaculum, a fibrous band, sheathes the tendons at the wrist over the palmar surface, while the extensor retinaculum extends over the dorsal surface. This setup is important to consider, as the flexed wrist position impacts the length-tension relationship of these muscles, leading to reduced grip strength.