SKELETAL SYSTEM

Parts of the skeletal system

• Bones (skeleton)

• Joints

• Cartilages

• Ligaments

Two subdivisions of the skeleton

Axial skeleton

Appendicular skeleton

Functions of the Bones

• Protect soft organs

• Support the body

• Attach skeletal muscles

• Store minerals and fats

• Blood cell formation (hematopoiesis)

Blood cell formation

(hematopoiesis)

The adult skeleton has

206 bones

Two basic types of osseous (bone) tissue

• Compact bone Dense, smooth, and homogeneous

• Spongy bone, Small needlelike pieces of bone Many open spaces

Bones are classified on the basis of shape into four groups

Long, Short, Flat, Irregular

Makes up most of bone’s length?

Diaphysis (shaft)

Outside covering of the diaphysis

Perosteum

Secures the periosteum to underlying bone

Perforating Fibers

Composed mostly of spongy bone enclosed by thin layer of compact bone (bone ends)

Epiphysis

Articular Cartilage

• Covers the external surface of the epiphyses

• Made of hyaline cartilage

Flat plate of hyaline cartilage seen in young, growing bone

Epiphyseal plate

Calcified epiphyseal plate, remnant of the EP

Epiphyseal line

Lines the inner surface of the shaft

Endosteum

Cavity inside the shaft

Medullary Cavity

BONE ANATOMY SUPERFICIAL TO DEEP

Perosteum → Perforating Fibers → Compact bone → Spongy bone →

Endosteum → Medullary Cavity → Bone marrow

Sites of attachments for muscles, tendons, and ligaments

BONE MARKINGS

Categories of bone markings

Depressions and Projections

Mature bone cells situated in bone matrix

OSTEOCYTES

Cavities in bone matrix that house osteocytes

LACUNAE

Concentric circles of lacunae situated around the central (Haversian) canal

LAMELLAE

Opening in the center of an osteon

Central Canals

Structural and functional unit of compact bone

OSTEON

A break in a bone?

Fracture

Types of bone fractures

• Closed (simple) fracture is a break that does not penetrate the skin

• Open (compound) fracture is a broken bone that penetrates through the skin

Bones are manually coaxed into position by physician’s hands

CLOSED REDUCTION

Bones are secured with pins or wires during surgery

OPEN REDUCTION

Repair of bone fractures involves four major events

Hematoma

FIBROCARTILAGE CALLOUS FORMS

Bony callus replaces fibrocartilage callus

Bone remodeling

TYPES OF FRACTURES

Comminuted (bone breaks to 3 or more pieces)

Depressed (indentation)

Spiral (twisted)

Greenstick (half broken)

Forms the longitudinal axis of the body

AXIAL SKELETON

(AXIAL SKELETON) Divided into three parts

Skull, Vertebral Column, Bony Thorax

Two sets of bones form the skull

Cranial bones

Facial bones

This bone is attached by a freely movable joint

MANDIBLE

Cranial bones are joined by?

Sutures

CRANIAL BONES THAT PROTECTS THE BRAIN

Frontal, Parietal, Occipital, Temporal, Ethmoid, Sphenoid

FACIAL BONES

MAXILLA, PALATINE, LACRIMAL, ZYGOMATIC, NASAL, VOMER,

INFERIOR NASAL CONCHAE, MANDIBLE

What type of suture is this?

CORONAL SUTURE

SUTURE

SQUAMOUS SUTURE

SUTURE

SAGITTAL SUTURE

SUTURE

LAMBDOID SUTURES

The only bone that does not articulate with another bone, Serves as a movable base for the tongue

Hyoid bone

Vertebral column (parts)

7 CERVICAL

12 Thoracic

5 Lumbar

Sacrum

Coccyx

26 vertebral bones are separated by?

Intervertebral discs

2 TYPES OF CURVATURES

C SHAPED (PRIMARY CURVATURES)

S SHAPED (SECONDARY CURVATURES)

VERTEBRAE PARTS

BODY, VERTEBRAL ARCH, VERTEBRAL FORAMEN, TRANSVERSE PROCESSES, SPINOUS PROCESS, FACET.

YES AND NO BONE OF VERTEBRAE

Atlas and Axis

BONT THORAX PARTS

Ribs, Sternum, Thoracic Vertebrae

PARTS OF THE RIBS

TRUE RIBS (7)

FALSE RIBS (5)

FLOATING (2)

PARTS OF THE APPENDICULAR BONES

Limbs, Pectoral girdle, Pelvic girdle

2 BONES OF THE PECTORAL GIRDLE

Scapula, Clavicle

FORMS THE UPPER ARM

Humerous

FOREARM BONES

Ulna, Radius

HAND BONES

Carpals, Metacarpals, Phalanges

How many bones in phalanges?

14

8 CARPAL BONES

TRAPEZIUM, TRAPEZOID, SCAPHOID, CAPITATE, HAMATE, LUMATE, PISIFORM, TRIQUETRUM

PELVIC GIRDLE’S 3 PAIR OF BONES

Ilium, Ischium, pubis

PELVIS GIRDLE PROTECTS?

Part of the large intestine, Urinary bladder, Reproductive organs ko

THIGH BONE

Femur

LOWER LEG BONES

TIBIA, FUBULA

BONES OF FEET

Tarsals, Metatarsals, Phalanges

TARSAL BONES

(MEDIAL, LATERAL, INTERMEDIATE) Cuneiform, Cuboid, Navicular, Calus, Calcaneus

JOINT CLASSIFICATIONS

Fibrous (immovable)

Cartilaginous (slightly movable)

Synovial (freely movable)

SOFT SPOTS IN A FETAL SKULL

FONTANELS

PHALANGES LOCATIONS

Distal, Medial, Proximal

LONG BONE PARTS

(LATERAL, MEDIAL,) Epicondyle, Head, Trochanter