Question

Can you explain in detail how a hand, wrist, and arm work together to left an object on a table from point A to point B. Such as the anatomy and Mechanics of the human hand. Example would be grabbing coke can and moving it to a different spot on table. (Talk about Wrist, Carpus, Metacarpus, Fingers, Muscles, Power grip, Connective tissue and tendons, etc.) Thank you and in paragraph form.

Answer 1

structure of hand :

The hand consists of wrist, palm and fingers

Movements of hand are controlled by muscles in the forearm (extrinsic muscles) as well as muscles within the hand ( intrinsic muscles) .

Bones of the hand :  

The skeleton of the hand can be divided into three sections;

1. Carpals (wrist)
2. Metacarpals(palm)
3. Phalanges(bones of the finger)

Muscles of the forearm affecting the hand:

The bulk of the muscles form the fleshy roundness of the forearm, with tendons extending into wrist and hand .

The muscles of forearm divided into Anterior and posterior compartments.

muscles in palm :

• The thenar eminence
• The hypothenar eminence
• Mid palm

Muscles of thumb:

The movements of thumb occur at a joint called the carpometacarpal joint , as well as at two joints involving phalanx.

Muscles of the fingers :

The movements of the remaining fingers of the hand are result of interplay between sever muscle groups.

Tendons of hand :

Most of the tendons pass under the transverse carpel ligament which is located underside of the wrist , and dorsal carpal ligament.

This prevents the tendons from standing up when muscle contract.

The tendon passing through the carpal tunnel are allowed them to side back and forth with ease.

Mechanics of human hand :

The hand moves by the muscles which bend the finger joints are located in the palm and up in the mid forearm, and are connected to finger bones by tendons , which pull on and move the fingers like the strings .

During grip work the muscles used are Flexor digitorum superficialas and flexor digitorum profundus and flexor policy's longus , which all originate up between the elbow and the upper portions of the forearm bones and insert down into the fingers