Skeletal System: Bones, Joints, and Anatomical Movements Study Guide

Skeletal System Overview

Introduction

The skeletal system provides the structural framework for the human body, protects vital organs, and enables movement through its interaction with muscles. This study guide covers the identification of bones, bone markings, joint classifications, and anatomical movements, as outlined in lab practical exercises 9, 10, and 11.

Exercise 9: Skull and Axial Skeleton

Major Bones of the Skull

• Eight cranial bones: Frontal, parietal, temporal, occipital, sphenoid, ethmoid.

• Major cranial sutures: Coronal, sagittal, squamous, lambdoid.

Key Points

• Skull cavities: Orbital cavity, nasal cavity, cranial cavity, maxillary sinus, conchal cavity, mastoid process.

• Axial skeleton bones: Skull, vertebral column, rib cage.

• Facial bones: Maxilla, mandible, zygomatic, nasal, lacrimal, palatine, vomer, inferior nasal concha.

• Major foramina: Foramen magnum, jugular foramen, optic canal, mental foramen, infraorbital notch.

• Paranasal sinuses: Frontal, sphenoid, ethmoid, maxillary.

• Vertebral column regions: Cervical, thoracic, lumbar, sacrum.

• Curvatures: Primary (thoracic, sacral), secondary (cervical, lumbar).

• Abnormal curvatures: Scoliosis, kyphosis, lordosis.

Example

• The foramen magnum is a large opening in the occipital bone through which the spinal cord passes.

Exercise 10: Appendicular Skeleton

Pectoral and Pelvic Girdles

• Pectoral girdle bones: Scapula, clavicle.

• Pelvic girdle bones: Ilium, ischium, pubis.

Key Points

• Scapula landmarks: Acromion, coracoid process, spine, supraspinous fossa, infraspinous fossa, subscapular fossa, glenoid cavity.

• Humerus landmarks: Head, greater tubercle, lesser tubercle, intertubercular groove, deltoid tuberosity, medial and lateral epicondyle, capitulum, trochlea, olecranon fossa.

• Forearm bones: Radius and ulna; radial styloid process, ulnar notch of radius, ulnar head, olecranon, trochlear notch.

• Hand bones: 8 carpals, including scaphoid, lunate, triquetrum, pisiform, trapezium, trapezoid, capitate, hamate; 5 metacarpals; 14 phalanges.

• Foot bones: 7 tarsals (medial, intermediate, lateral cuneiform, cuboid, navicular, talus, calcaneus), 5 metatarsals, 14 phalanges.

• Foot arches: Medial and lateral longitudinal arches, transverse arch.

Example

• The glenoid cavity of the scapula articulates with the head of the humerus to form the shoulder joint.

Exercise 11: Joints and Movements

Anatomical Movements

• Abduction: Movement away from the midline.

• Adduction: Movement toward the midline.

• Rotation: Movement around an axis.

• Circumduction: Circular movement combining flexion, extension, abduction, and adduction.

• Pronation/Supination: Rotation of the forearm; pronation turns the palm down, supination turns it up.

• Protraction/Retraction: Moving a body part forward/backward.

• Flexion/Extension: Decreasing/increasing the angle between bones.

• Opposition: Movement of the thumb to touch other fingers.

• Dorsiflexion/Plantar flexion: Upward/downward movement of the foot.

• Inversion/Eversion: Turning the sole of the foot inward/outward.

Joint Classifications

• Structural classification: Synchondroses, synostoses, suture, syndesmoses, symphosis, synovial joints.

• Functional classification: Synarthrotic (immovable), amphiarthrotic (slightly movable), diarthrotic (freely movable).

Examples of Synovial Joints and Movements

Joint Type	Example	Movement
Plane	Intercarpal joints	Gliding
Hinge	Elbow, knee	Flexion, extension
Pivot	Proximal radioulnar joint	Rotation
Condylar	Metacarpophalangeal joints	Flexion, extension, abduction, adduction
Saddle	Thumb (carpometacarpal joint)	Opposition
Ball-and-socket	Shoulder, hip	Flexion, extension, abduction, adduction, rotation

Additional Key Points

• Knee joint: Articulation between femur and tibia; includes menisci and ligaments for stability.

• TMJ (temporomandibular joint): Functions in jaw movement; includes superior and inferior disc, movements: elevation, depression, protraction, retraction, lateral excursion.

Formulas

• Range of Motion (ROM): $ROM = \theta_{max} - \theta_{min}$

Summary Table: Major Bones and Features

Region	Main Bones	Key Landmarks
Skull	Frontal, parietal, temporal, occipital, sphenoid, ethmoid	Foramen magnum, coronal suture, mastoid process
Vertebral Column	Cervical, thoracic, lumbar, sacrum	Spinous process, vertebral foramen
Pectoral Girdle	Scapula, clavicle	Acromion, glenoid cavity
Upper Limb	Humerus, radius, ulna	Olecranon, trochlea, capitulum
Hand	Carpals, metacarpals, phalanges	Scaphoid, lunate, trapezium
Pelvic Girdle	Ilium, ischium, pubis	Acetabulum, obturator foramen
Lower Limb	Femur, tibia, fibula	Patella, medial/lateral condyles
Foot	Tarsals, metatarsals, phalanges	Talus, calcaneus, arches

Additional info: Academic context and definitions have been expanded for clarity and completeness. The original file contained a list of topics and identification requirements for a lab practical exam in Anatomy & Physiology, focusing on the skeletal system and joints.