Anatomy of the Human Upper Limb

11 Questions

Which bones make up the forearm?

Radius and ulna

What is the function of ligaments in the upper limb?

Improve joint stability and maintain proper alignment

Name two muscles that act on the joints of the upper limb.

Deltoid and biceps brachii

Which arteries deliver oxygenated blood towards the digits in the upper limb?

Brachial and radial arteries

What is the role of tendons in the upper limb?

Connect muscles to bones via pulleys to optimize force transmission

List three primary joints of the upper limb.

Glenohumeral, radioulnar, metacarpophalangeal

What is the main function of lymphatics in the upper limb?

Transporting lymph throughout the limb, contributing to immune defense and waste removal.

Which nerve plexus provides motor and sensory innervation to the entire upper limb?

Brachial plexus.

Name four major nerves that originate from the brachial plexus and innervate the upper limb.

Median, ulnar, radial, and musculocutaneous nerves.

What are movement primitives or subphases used for in understanding upper limb function?

Structuring movements into functional units.

How do anatomic components and organization of the human upper limb contribute to its versatile capabilities?

By enabling robust evaluation and prosthetic device optimization.

Study Notes

Exploring the Anatomy of the Human Upper Limb

The human upper limb is a remarkable combination of bones, muscles, ligaments, nerves, arteries, and veins, extending from the shoulder to the fingertips. Its intricate design allows for fine motor skills, agility, and adaptability.

Principal Components of the Upper Limb

Bones: Consisting of one bone in the upper arm (the humerus), two bones in the forearm (radius and ulna), and the numerous smaller bones in the hand, these structures provide support and facilitate movement.
Muscles: Arranged into anatomical compartments, these muscles act on the various joints of the hand, arm, and shoulder. Examples include the deltoid, biceps brachii, triceps brachii, extensor digitorum communis, flexor digitorum superficialis, and the radial nerve innervates them.
Ligaments: Serving as tough fibrous bands connecting bones to improve joint stability and maintain proper alignment. Notably, false ligaments called tendons connect muscles to bone via pulleys that optimize force transmission.
Joints: The primary joints of the upper limb include the glenohumeral, radioulnar, radio-capitate-lunate, metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints.
Blood Vessels: Providing oxygen and nutrients to tissues, the upper limb's vascular network includes the brachial and radial arteries delivering oxygenated blood towards the digits and back via the cephalic and basilic veins.
Lymphatics: Transporting lymph throughout the limb, contributing to immune defense and waste removal.
Nerves: The brachial plexus, consisting of five nerve roots exiting the neck, provides motor and sensory innervation to the entire upper limb and sends signals via major nerves like the median, ulnar, radial, and musculocutaneous nerves.

Organization of Movement

To better comprehend upper limb function, researchers structure movements based on functional units known as movement primitives or subphases, which include reaching, transport, grasping, etc. These building blocks allow for robust evaluation and prosthetic device optimization.

Understanding the anatomic components and organization of the human upper limb enables us to appreciate its versatile capabilities and facilitates rehabilitation efforts following injury.