Anatomy of the Arm

Study Notes

Anatomy of the Arm

The arm is the region between the shoulder and the elbow and is primarily composed of the humerus.
The humerus is a long bone, extending from the shoulder joint to the elbow joint. It's the longest bone in the upper arm.
The humerus articulates with the scapula at the glenoid cavity to form the shoulder joint.
It articulates with the radius and ulna at the elbow joint.
Key humerus features include the head, anatomical neck, greater and lesser tubercles, deltoid tuberosity, and medial and lateral epicondyles.
Arm muscles control flexion, extension, abduction, and adduction at the shoulder and elbow joints.
Major arm muscles include biceps brachii, triceps brachii, brachioradialis, and coracobrachialis.
The brachial artery and median nerve carry blood and sensory signals to arm muscles and skin.
The axillary artery branches from the subclavian artery, supplying blood to the brachial artery.
The radial and ulnar nerves branch from the brachial plexus, providing sensory function to the forearm and hand.

Anatomy of the Forearm

The forearm extends between the elbow and the wrist and is composed of two bones: the radius and the ulna.
The radius is located on the lateral (thumb) side of the forearm.
The ulna is located on the medial (pinky finger) side of the forearm.
The radius and ulna are connected by an interosseous membrane, allowing some movement between them.
Both bones articulate with the humerus at the elbow joint and with carpal bones at the wrist.
Forearm muscles control wrist and hand movements.
Forearm muscles are organized into anterior and posterior compartments.
Anterior compartment muscles cause flexion; posterior compartment muscles cause extension.
Anterior forearm muscles include flexor carpi radialis, palmaris longus, flexor carpi ulnaris, and flexor digitorum superficialis.
Posterior forearm muscles include extensor carpi radialis, extensor carpi ulnaris, and extensor digitorum.
The anterior and posterior compartments are separated by the interosseous membrane.
The brachial artery branches into the radial and ulnar arteries to supply blood to forearm muscles and structures.
The median, ulnar, and radial nerves run through the forearm, providing sensory and motor function to the hand.
These nerves pass through the elbow region and into the forearm and potentially through the elbow region again. This allows them to interact with many forearm and hand muscles.
Ligaments, tendons, and associated structures of the forearm support movement, stability, and upper extremity function.

Associated Structures

Forearm tendons attach to various hand and wrist regions.
The wrist joint is a complex synovial joint formed by the distal ends of the radius and ulna and several carpal bones.
Carpal bones, combined with the radius and ulna, create the wrist's varying mobility and structure.
Ligaments stabilize the wrist joint.
Numerous tendons connect to hand bones, enabling complex hand movements.
The palm and associated structures support and enable fine finger movements.

Description

This quiz explores the anatomy of the arm, focusing on the humerus and its structures. You'll learn about the joints, muscles, and vessels that contribute to the function of the arm. Test your knowledge of key anatomical features and their roles in movement.