Lab 06 & 07 - Connective Tissue & Musculoskeletal System Notes

Lab 06 & 07 - Part II: Connective Tissue & Musculoskeletal System

General Overview

• Focus: Anatomical structures of the upper and lower limbs, including bones and muscles.

• Importance of understanding origin-insertion-action (OIA) for muscle functionality.

Bones of the Upper Limb

• Scapula: Flat bone providing attachment points for muscles.

  • Features: Acromion, glenoid cavity, scapular spine.

• Clavicle: S-shaped bone, connects the upper limb to the trunk.

• Humerus: Long bone of the arm.

  • Key features include:

  • Greater and lesser tubercles (muscle attachment points).

  • Anatomical and surgical necks.

  • Deltoid tuberosity (attachment for deltoid muscle).

  • Olecranon fossa (for elbow joint).

  • Medial and lateral epicondyles (muscle attachment).

• Radius and Ulna: Forearm bones.

  • Radius: Lateral bone, involved in wrist movement.

  • Ulna: Medial bone, forms the elbow joint.

Muscles of the Upper Limb

• Pectoralis Major:

  • Origin: Clavicle, sternum, and costal cartilages.

  • Insertion: Proximal humerus.

  • Action: Flexion and adduction of the humerus.

• Deltoid:

  • Origin: Acromion and spine of scapula.

  • Insertion: Deltoid tuberosity of humerus.

  • Action: Abduction of the humerus.

• Biceps Brachii:

  • Origin: Glenoid cavity and coracoid process.

  • Insertion: Radial tuberosity.

  • Action: Elbow flexion.

• Triceps Brachii:

  • Origin: Glenoid cavity and humerus.

  • Insertion: Olecranon.

  • Action: Elbow extension.

Bones of the Lower Limb

• Femur: Thigh bone, longest in the body.

• Tibia and Fibula: Bones of the lower leg, with tibia being the larger and stronger bone.

  • Calcaneus: Heel bone.

  • Tarsal and Metatarsal bones: Form the foot structure.

  • Phalanges: Toe bones.

• Pelvic Girdle: Comprises ilium, pubis, and ischium.

Muscles of the Lower Limb

• Quadriceps Group (Anterior thigh):

  • Includes Rectus femoris, Vastus intermedius, Vastus lateralis, and Vastus medialis.

  • Action: Knee extension.

• Hamstring Group (Posterior thigh):

  • Comprises Semitendinosus, Biceps femoris, and Semimembranosus.

  • Action: Knee flexion.

• Gluteal Muscles: Important for hip movement.

  • Gluteus Maximus:

  • Origin: Posterior ilium and sacrum.

  • Insertion: Gluteal tuberosity of femur.

  • Action: Extension and lateral rotation of thigh.

  • Gluteus Medius:

  • Origin: Lateral surface of ilium.

  • Insertion: Greater trochanter of femur.

  • Action: Abduction and medial rotation of thigh.

  • Gluteus Minimus: Similar function to gluteus medius but smaller.

Summary of OIA for Muscles

• Understanding OIA is crucial for analyzing how muscles interact with joints to facilitate movement.

• Several muscles may share the same origin but have different insertions and actions, demonstrating functional diversity.

These notes encapsulate both the anatomical structures and dynamic aspects of the musculoskeletal system pertinent to the examinations being prepared for in Lab 06 and 07.