ANHB1101__Bones__Joint___Movement_
BONES, JOINTS & MOVEMENT
The skeletal system forms the framework of the body.
Importance of Knowing Bone Names:
Helps locate and name anatomical features.
Example: Radial artery near the radius, ulnar nerve near the ulna.
Aids in comparative anatomy of primates and human ancestors.
Enhances understanding of evolutionary relationships.
Classification of Bones
Bones classified by shape:
Long bones: Greater length than width.
Short bones: Nearly equal in length & width; cube-shaped.
Flat bones: Thin, protect organs, and provide muscle attachment areas.
Irregular bones: Complex shapes.
Sesamoid bones: Develop in tendons under friction, tension, and stress.
Divisions of the Skeletal System
Axial Skeleton:
Primary function: Protection of internal organs.
Appendicular Skeleton:
Primary function: Movement.
Musculoskeletal system consists of bones, muscles, and joints.
Learning Objectives
Identify various bones of the axial and appendicular skeleton.
Understand the pectoral and pelvic girdles.
Describe movements possible at joints.
Vocabulary for the Topic
appendic: Hang onto
sesamoid: Like a sesame seed
mand: To chew
tempor: Temple
ab: Away from
ad: Towards
duc: To lead; carry
circum: Around
flex: To bend
extens: Draw out
pro: Forward
re: Back
trac: Pull in
e: Outward
vert: To turn
pecto: Chest
pelvis: Basin
arthrosis: Articulation of bones, joint
planto: Sole of the foot
Movements at Joints
Movements occur in specific planes and often in pairs.
Correct anatomical language is crucial.
Example: "Flexion of the leg at the knee."
Types of Movements
Flexion:
Plane: Sagittal
Movement towards ventral surface, decreases joint angle.
Extension:
Plane: Sagittal
Movement towards dorsal surface, increases joint angle.
Hyperextension:
Plane: Sagittal
Movement past the anatomical position.
Abduction:
Plane: Frontal
Movement away from the midsagittal plane.
Adduction:
Plane: Frontal
Movement towards the midsagittal plane.
Rotation:
Plane: Transverse
Bone spins on its longitudinal axis.
Circumduction:
Multi-plane movement; proximal end stationary, distal end describes a circle.
Pronation:
Plane: Transverse
Palm faces posteriorly.
Supination:
Plane: Transverse
Palm faces anteriorly.
Dorsiflexion:
Plane: Sagittal
Toes lifted off the ground, standing on heels.
Plantar flexion:
Plane: Sagittal
Standing on toes.
Elevation:
Plane: Frontal
Raises a body part.
Depression:
Plane: Frontal
Lowers a body part.
Eversion:
Plane: Frontal
Lateral side of foot raised off the ground.
Inversion:
Plane: Frontal
Medial side of foot raised off the ground.
Protraction:
Plane: Transverse
Moves body part anteriorly/forwards.
Retraction:
Plane: Transverse
Moves body part posteriorly/backwards.
Axial Skeleton
Consists of bones surrounding the body’s longitudinal axis.
Skull:
Superior to vertebral column (2 answers).
Components: Cranium, Face.
Vertebral Column:
Inferior to skull (2 answers).
Posterior to sternum (2 answers).
Heart is deep to ribs.
Hyoid Bone:
Functionally not part of axial or appendicular skeleton, grouped with axial for convenience.
Cranial Bones
Frontal: Forms forehead & parts of cranial floor.
Parietal: Sides and roof of the cranium.
Temporal: Inferior lateral aspect and part of cranial floor.
Occipital: Forms posterior part of cranium.
Sphenoid: Butterfly shape, articulates with all other cranial bones.
Ethmoid: Sponge-like appearance in anterior cranial floor.
Facial Bones
Maxilla: Forms upper jaw, articulates with every facial bone except mandible.
Zygomatic: Cheekbones, articulates with several skull bones.
Mandible: Lower jaw, only movable skull bone (excluding auditory ossicles).
Vertebral Column
Composed of spinal bones (vertebrae).
Regional Identification:
Cervical (7): Neck region; smaller than other vertebrae, has transverse foramen.
Thoracic (12): Chest region; larger; articulates with ribs.
Lumbar (5): Lower back; largest of unfused vertebrae.
Sacrum (5): Triangular bone formed by sacral vertebrae fusion.
Coccyx (4): Triangular, formed by coccygeal vertebrae fusion.
Functions of the Vertebral Column
Support of head and trunk (weight-bearing).
Protection of the spinal cord.
Attachment site for muscles (movement).
Attachment site for ribs and pelvis.
Appendicular Skeleton
Composed of bones of the upper/lower limbs and girdles connecting them to the axial skeleton.
Pectoral Girdles:
Attach upper limb bones to the axial skeleton.
Held in place by muscles, do not articulate with the vertebral column.
Pelvic Girdle (Coxal Bones):
Connects lower limb bones to axial skeleton.
Formed from fusion of ilium, ischium, and pubis.
Pectoral Girdle Structures
Clavicle: Articulates with scapula and sternum.
Scapula: Articulates with humerus and clavicle.
Upper Limb Structures
Proximal bones:
Humerus (arm).
Scapula (forearm).
Ulna and Radius (forearm).
Pelvic Girdle Structures
Coxal Bones: Articulate with femurs and sacrum.
Lower Limb Structures
Proximal bones:
Femur (thigh).
Tibia and Fibula (leg).
Tarsals, Metatarsals, and Phalanges (foot).
Exam Practice
Identify and label joint movements shown in diagrams: abduction, flexion, inversion, etc.
Name movements that produce circumduction: Flexion, Abduction, Extension, Adduction, Rotation (or reverse).
Future Study Suggestions
Consider enrolling in level 2 units like ANHB2212, ANHB2214, or others related to Human Biology.
Career Pathways
Roles in various fields such as:
Anatomist, Forensic Anatomist, Physiotherapist, Physician, Nurse, Paramedic, Occupational Therapist.