Care of the Patient with a Musculoskeletal Disorder

PN 135

Overview of Anatomy and Physiology

• Divisions of the skeleton–Axial-• Cranium (skull, face, and ears), vertebrae,

ribs–Appendicular• Limbs, shoulders, pelvis, hips

Divisions of Skeleton

• 206 bones total• Axial skeleton– 80 bones– Head & trunk

• Appendicular skeleton– 126 bones– Extemeties, shoulders, hips

Figure 44-2

Skeleton, anterior view.

(From Thibodeau, G.A., Patton, K.T. [1997]. The human body in health and disease. [2nd ed.]. St. Louis: Mosby.)

Figure 44-3

Skeleton, posterior view.

(From Thibodeau, G.A., Patton, K.T. [1997]. The human body in health and disease. [2nd ed.]. St. Louis: Mosby.)

Overview of Anatomy and Physiology

• Functions of the skeletal system– Support–Protection–Mineral storage-calcium/phosphorus–Movement–Hemopoiesis

• Structure of bones– Long, short, flat, and irregular

Functions of the Skeletal System

• Support– Rigid framework– Supports against pull of gravity– “hanger” for our muscles!

Functions of the Skeletal System

• Protection– Soft body parts– Brain– Heart– Lungs– Vascular system

Functions of the Skeletal System

• Movement– Provide sites for muscle attachment– Bones and muscles work together as simple

mechanical lever systems to produce body movements.

Functions of the Skeletal System

• Mineral Storage– The bones serve as a storage specifically for 2

minerals—calcium and phosphorus– Intercellular matrix of bone contains large

amounts of…• Calcium• When blood calcium levels drop• Calcium is released from the bones• Excess Calcium is stored in the bone

Functions of the Skeletal System

• Storage– Bone tissue contains smaller amounts of…• Sodium • Magnesium• Potassium• Carbonate

Functions of the Skeletal System

• Hematopoesis – Blood cell formation– Takes place in red marrow of bones– Infants primarily have red marrow– As we age red marrow changes to yellow marrow

for fat storage

Functions of the Skeletal System

• Hematopoesis (cont.)

– Adults• Red marrow is limited to the spongy bone–Skull–Ribs–Sternum–Clavicles–Vertebrae–Pelvis

Functions of the Skeletal System

• Red Marrow Functions– Formation of…• Red Blood Cells• White Blood Cells• Blood Platelets

Functions of the Skeletal System

• Red Marrow (summary)– Manufactures blood cells – Found in ends of long bones– Center of other bones

• Yellow Marrow (summary)– Shaft of long bones– Composed largely of fat

Bones

• Bones stop growing in length by late teens, early 20’s

• Children- bone repair is much faster• Elderly- past active phase, repair takes longer,

bones more fragile

Types of Bone

• Types of Osseous/Bone Tissue• Cancellous– Spongy

• Epiphysis, end of long bone & center or others• Filed with red marrow

• Cortical– Compact

• Diaphysis, shaft of long bone• Outer layer of other bones• Haversion canal contains nerves and blood vessels

Types of Bones

• Short bones and flat bones– Cancellous/spongy covered by Cortical/compact

• Irregular – e.g. vertebrae• Long bones– Ends are Cancellous/Spongy– Shafts are Cortical/Compact

Types of Bone

• Four classifications based on form and shape:– 1. Long – eg. Humerus– 2. Short – eg. Phalanges of the fingers– 3. Flat – eg. Occipital, sternum– 4. Irregular - eg. Vertebrae

Classification

• Long Bones: longer than they are wide

• Short Bones: – roughly cube-shaped– Vertical and horizontal dimensions approx. =– E.g. Wrist, ankle

Classification

• Flat bones: – Thin, flattened, usually curved– Made like sandwich with a middle layer of

spongey bone called diploӫ. The diploӫ is covered on each side by a layer of compact bone.

– E.g. Cranium

Classification

• Irregular Bones– One of a group of bones having peculiar or

complex forms• E.g vertebrae

Structure of Bones

Bone Membranes

• Periosteum– Membrane on outside of bone– Contain osteoblasts

• Endosteum– Lines marrow cavity– Cells aid in growth and repair

Bone Cells and Actions

• Osteoblasts- build bone• Osteocytes- are mature bone cells • Osteoclasts- break bone down

Projections

• Head- rounded knob– At end of bone– E.g. ____________________

• Process- large projection– E.g. Spinous process on vertabrae

• Crest- border or ridge– E.g. __________________

• Spine- sharp projection– E.g. spine of scapula

Depressions or Holes

• Foramen- hole allows vessel or nerve to pass through

• Sinus- air space in some skull bones• Fossa- depression• Meatus- short channel or passage– E.g. Passage to inner ear

12 Ribs

• True Ribs– First seven pair– Attach to sternum by costal cartilage

• False Ribs– Next five pair• 8th, 9th, & 10th attach to rib above • 11th & 12th have no anterior attachment (Floating ribs)

Vertebral Column

• Cervical vertebrae- 7, support & move head• Thoracic vertebrae- 12, ribs attached here• Lumbar vertebrae- 5, support weight• Sacral vertebrae- 5, fuse to single bone• Coccyx – 4-5 in child– Fuse to 1 in adult

Bones and Joints

Bones and Joints

• Bursa– Fluid-filled sacs– Joint movement

• Fascia– Connective tissue– Includes tendons, ligaments, and aponeuroses

• Tendons– Attach muscle to bones

• Ligaments– Bind joints together

Overview of Articulations

• Articulations (joints)Connect bones and allow movement–Three types according to degree of

movement• Synarthrosis—no movement• Amphiarthrosis—slight movement•Diarthrosis—free movement

Joints

• Diarthrosis-freely moveable– Hinge: elbow, knee– Ball and socket: hip and shoulder– Pivot: skull and 1st vertabrae

• Synarthrosis-immovable– Sutures

• Amphiarthrosis-slightly movable– Vertebrae and pelvis

Diarthrosis• Hinge: permitting only flexion and extension as in

the elbow and knee joints.

• Gliding: Flat or slightly flat surfaces move against each other allowing sliding or twisting. This happens in the carpals in the wrist and the tarsals in the ankle.

Diarthrosis• Ball-and-Socket: The ball-shaped end of one

bone fits into a cup shaped socket on the other bone allowing the widest range of motion including rotation. Examples include the shoulder and hip.

• Pivot: An example is the joint between the axis and atlas in the neck.

Diarthrosis

• Articulating Joints– Covered with articular cartilage– Have joint capsules• Outer layer-fibrous• Inner layer- synovial, secretes synovial fluid to lubricate

joints

Types of Joints

Structure of a freely movable (diarthrotic) joint.

Synovial Joint Movement

• Flexion-decreases angle between bones (close fingers)

• Extension-increases angle between bone (open fingers)

• Abduction-movement away from midline• Adduction-movement toward midline

Joint Movement

• Rotation-twisting or turning–Supination-turn up–Pronation-turn down– Inversion-turning inward–Eversion-turning outward

Synarthrosis and Amphiarthrosis

• Fibrous joint– Fibrous connective tissue– E.g. sutures in skull– Immovable, synarthrosis

• Cartilaginous joint– Connected by cartilage– E.g. vertebrae and ribs connecting to sternum– Slightly movable, amphiarthrosis