Question

1. What is the primary action occurring at the radiocarpal joint in phase 1 pictured above? What are the three primary muscles involved in this action?

2. Grip strength is an important factor for both hands in the activity of opening a jar. In this example of opening the peanut butter container, think about the muscles that are working to hold on to the container and the lid. Name two antebrachial muscle and two intrinsic hand muscle assisting with the actions taking place at the metacarpophalangeal and proximal and distal interphalangeal joints of digits II-V of both hands. What type of contraction would your chosen muscles be performing to grip the jar and lid?

Answer 1

1) Radial deviation in phase 1,three primary muscles are flexor carpi radialis,extensor carpi radialis longus, extensor carpi radialis brevis.

2) Muscles for grip - forearm flexors and forearm extensors.

Two antebrachial muscle- flexor digitorum profundus and flexor pollicis longus and lumbricals.

Intrinsic muscles of hand- abductor pollicis brevis,opponens pollicis, flexor pollicis brevis etc.