Nurs 1002-Lab #5

The Skeleton & Articulations

Lab Overview

This study guide covers the structure and function of the human skeleton and its articulations, focusing on bone identification, anatomical landmarks, and clinical relevance. It is designed to reinforce concepts from Chapter 7 (The Skeleton) and Chapter 8 (Joints) of a standard Anatomy & Physiology curriculum.

The Skull

Adult vs. Fetal Human Cranium

The human skull consists of several bones connected by sutures. The configuration of these bones changes from fetal development to adulthood.

• Sutures: Immovable joints between skull bones. In adults, sutures are fused and rigid; in fetuses, bones are not fused, allowing for growth and flexibility.

• Fontanelles: Soft spots in the fetal skull where bones have not yet fused.

• Clinical Relevance: Differences in suture fusion are important for growth and development. Premature fusion can lead to skull deformities and developmental issues.

Example: The anterior fontanelle in infants allows for brain growth and is used as a clinical landmark.

The Spine

Regions and Vertebrae

The vertebral column is divided into distinct regions, each with a characteristic number of vertebrae.

Region	Letter	# of Vertebrae
Cervical	D	7
Thoracic	E	12
Lumbar	B	5
Sacrum	C	5 fused bones
Coccyx	A	3-5 fused bones

Additional info: The vertebral column provides structural support and protects the spinal cord.

The Thoracic Cage

Structure and Function

The thoracic cage consists of the ribs, sternum, and associated cartilages, protecting vital organs and facilitating respiration.

• Key Structures: Costal cartilage, body of sternum, false ribs, clavicle, manubrium, xiphoid process.

• Organs Protected: Heart, lungs, and parts of the respiratory tract.

• Respiratory Movement: Costal cartilage allows the thoracic cavity to expand during breathing.

• CPR Landmark: The sternum is used for compressions, avoiding the xiphoid process.

The Pectoral Girdle

Bone Identification and Movements

The pectoral girdle connects the upper limb to the axial skeleton and allows a wide range of movements.

• Key Bones: Acromion, glenoid cavity, humerus, clavicle, coracoid process, scapula.

• Movements: External, internal, anterior, and posterior rotation of the arm.

• Clinical Relevance: Shoulder injuries often involve the pectoral girdle.

The Upper Limbs

Bones and Articulations

The upper limb consists of several bones that articulate to allow complex movements.

• Key Bones: Clavicle, shoulder joint, scapula, humerus, elbow joint, ulna, radius, carpals, metacarpals, phalanges.

• Articulation: The radius and ulna cross over each other during pronation and supination.

• Carpal Bones: There are 8 carpal bones in the wrist.

The Pelvic Girdle

Structure and Gender Differences

The pelvic girdle supports the lower limbs and protects pelvic organs. It consists of the ilium, ischium, and pubis.

• Key Landmarks: Iliac crest, anterior superior iliac spine, pubic symphysis, ischial tuberosity.

• Gender Differences: Female pelvis is wider and more circular for childbirth; male pelvis is narrower and more triangular.

• Clinical Relevance: Landmarks are important for physical examinations and diagnosis.

Lower Limbs

Bones and Landmarks

The lower limb includes the femur, patella, tibia, and fibula, each with important anatomical landmarks.

• Key Bones: Femur, patella, tibia, fibula.

• Landmarks on Femur: Head of femur, greater trochanter, lateral epicondyle.

• Clinical Relevance: Landmarks are used for physical exams and locating bones for procedures.

Joints

Major Joints and Movements

Joints connect bones and allow movement. Major joints include the hip, knee, and shoulder.

• Hip Joint: Formed by the pelvis and femoral head; allows ball-and-socket movement.

• Knee Joint: Formed by femur, patella, and tibia; includes ligaments such as ACL and menisci.

• Shoulder Joint: Formed by scapula, humerus, and clavicle; allows a wide range of motion.

Joint	Type of Synovial Joint	Movement of the Synovial Joint
Hip	Ball and Socket	Multiaxial: flexion, abduction, adduction, and extension, medial and lateral rotation
Shoulder	Ball and Socket	Multiaxial: flexion, abduction, adduction, and extension, medial and lateral rotation
Elbow	Hinge	Uniaxial: flexion and extension
Knee	Hinge	Uniaxial: flexion and extension
Wrist	Condylar synovial joint	Biaxial: flexion, extension, pronation, supination

Joint Movements Terminology

Movement	Name of the Joint
Supination/Pronation	Radioulnar joint (elbow)
Inversion/Eversion	Subtalar joint and Transverse tarsal joint (ankle joint)
Radial/Ulnar deviation	Radiocarpal joint (wrist)
Plantarflexion/Dorsiflexion	Talocrural joint (ankle joint)

Long Bone Structure

Sections and Functions

Long bones have distinct regions, each with specific functions.

Section of Bone	Function
Diaphysis	Tubular shaft forming long axis of bone
Epiphysis	Ends of long bone made of spongy bone
Epiphyseal Lines	Remnants of epiphyseal plates; site of bone growth during youth
Periosteum	Covers outside of compact bone
Articular (hyaline) cartilage	Provides support, flexibility, and resilience

Clinical Applications

Fractures and Anatomical Landmarks

Understanding bone anatomy is essential for diagnosing fractures and planning treatments.

• Fracture Identification: Use anatomical terms to describe location (e.g., proximal, distal, shaft/diaphysis, epiphysis).

• Landmarks for Injections: Knowledge of muscle and bone landmarks is crucial for safe and effective intramuscular injections.

• Medication Administration: Subcutaneous and intramuscular injections are administered based on anatomical layers and absorption rates.

Example: The greater trochanter is a landmark for intramuscular injections in the hip.

Summary Table: Major Bones of the Skeleton

Number	Bone
1	Frontal bone
2	Mandible
3	Clavicle
4	Thoracic
5	N/A lumbar
6	Scapula
7	Coccyx
8	Ribs
9	Humerus
10	Ulna
11	Radius
12	Carpals
13	Metacarpals
14	Phalanges
15	Femur
16	Tibia
17	Fibula
18	Patella
19	Calcaneus
20	Phalanges

Key Equations and Concepts

• Bone Growth: $\text{Epiphyseal Plate Growth} \rightarrow \text{Longitudinal Bone Growth}$

• Joint Classification: $\text{Synovial Joints} = \text{Ball and Socket, Hinge, Condylar, etc.}$

Additional info: These notes provide a comprehensive overview suitable for exam preparation in Anatomy & Physiology, focusing on skeletal structure, joint function, and clinical applications.