Upper Limb Muscle exercises 7 lab

Oct 9, 2024

Lecture Notes: Muscles of the Upper Limb

Overview

  • Presentation by Professor McCurdy on the muscles of the upper limb using a model.
  • Focus on identifying and describing various muscles in the shoulder, arm, and forearm.

Shoulder Muscles

  • Pectoralis Major: Located on the anterior side.
  • Deltoid: Located laterally; removal exposes underlying muscles.
  • Infraspinatus: Located inferior to the spine of the scapula in the infraspinous fossa.
  • Supraspinatus: Located superior to the spine in the supraspinous fossa.
  • Teres Minor and Major: Teres minor is next to teres major; major goes anterior to the long head of the triceps brachii.
  • Subscapularis: Found in the subscapular fossa.

Arm Muscles

  • Biceps Brachii: Composed of long and short heads; both attach to the scapula and the radial tuberosity.
  • Brachialis: Originates on the humerus and attaches to the ulna; primary flexor of the forearm.
  • Triceps Brachii: Has three heads - long, lateral, and medial; long head attaches to the scapula, lateral and medial attach to the humerus, all attach to the ulna.
  • Coracobrachialis: Not visible in the model.

Forearm Muscles

  • Anterior (Flexor) Side:

    • Brachioradialis: Originates from the arm, attaches to the styloid process of the radius.
    • Pronator Teres: Positioned to pronate the forearm.
    • Flexor Carpi Radialis: Flexes wrist towards the radial/thumb side.
    • Palmaris Longus: Tendon attaches to the palm.
    • Flexor Carpi Ulnaris: Flexes wrist towards the ulnar/pinky side.
    • Flexor Digitorum Superficialis: Tendons extend to the fingers.

  • Posterior (Extensor) Side:

    • Extensor Carpi Ulnaris: Attaches to the fifth metacarpal.
    • Extensor Digiti Minimi: Extends the smallest digit.
    • Extensor Digitorum: Extends the second, third, and fourth digits.
    • Extensor Carpi Radialis Longus and Brevis: Flexes towards the radial side.

Key Concepts

  • Muscle Positioning: Anterior muscles generally act as flexors, while posterior muscles act as extensors.
  • Anatomical Orientation: Understanding the model's orientation is critical for identifying muscle locations and functions.

This summary is a guide to the structure and function of each muscle discussed during the lecture, providing a clear understanding of their anatomical positioning and roles.