Chapter 23: MSK Flashcards
Why do humans need the MSK system?
- for support and to stand erect
- for movement
- to encase and protect the inner vital organs
- to produce the RBCs, WBCs and platelets in the bone marrow
- as a reservoir for storage (Ca and PO)
How many bones does the body consist of? What type of tissue are bones and cartilage made of?
206 (bones and cartilage are forms of connective tissue)
What is a joint?
a place of union of two or more bones (functional units of the MSK b/c they permit the mobility needed for ADLs
These joints are freely moveable b/c their bones are separated from one another and enclosed in a joint cavity
synovial
** cartilage is avascular and gets nourishment from synovial fluid **
What is a bursa?
an enclosed sac filled w/viscous synovial fluid (like a joint); located in areas of potential friction and helps muscles and tendons glide smoothly over bone
What are some facts about muscles?
- they account for 40%-50% of body weight
- contraction produces movement
- theres 3 types (skeletal, cardiac and smooth)
What are some facts about skeletal muscles?
- composed of bundles of muscle fibers (fasciculi)
- skeletal muscle attached to bone by tendons (a strong fibrous cord)
- produce the following movements:
> flexion (bending of limb to joint)
> extension (straightening of limb)
> abduction (away from midline)
> adduction (towards midline)
> pronation (palm down)
> supination (palm up)
> circumduction (moving arm in circle)
> inversion (sole of foot inward)
> eversion (sole of foot outward)
> rotation (moving head around central)
> protraction
> retraction
> elevation (raising a body part)
> depression (lowering a body part)
What is the temporomandibular joint?
the articulation of the mandible and temporal bone; found in the depression anterior to the tragus of the ear. TMJ permits jaw function for speaking/chewing and allows 3 motions:
- open and close jaw
- gliding action for protrusion/retraction
- gliding for side to side movement of the lower jaw
How many bones does the vertebrae have?
33 connecting bones
What are the motions of the vertebral column?
- flexion (bending forward)
- extension (bending back)
- abduction (to either side)
- rotation
What is the shoulder girdle?
a belt of 3 large bones (humerus, scapula and clavicle), joints and muscles
This is the articulation of the humerus with the glenoid fossa of the scapula
glenohumeral joint
** ball and socket action in arm allows for great mobility of the arm **
What are the 4 muscles of the rotator cuff?
SITS muscles:
- supraspinatus
- infraspinatus
- teres minor
- subscapularis
These joints permit finger flexion and extension
metacarpophalangeal and interphalangeal
What are the muscles of the knee?
- articulation of 3 bones: the femur, tibia and patella
- largest joint in the body with the largest synovial membrane (forming a sac called suprapatellar pouch)
- the medial and lateral menisci cushion the tibia and femus
These ligaments give anterior and posterior stability and help control rotation
cruciate ligamants
These ligaments connect the joint at both sides, giving medial and lateral stability and preventing dislocation
collateral ligaments
The aging adult:
- older women have a greater amount of bone loss then men due to dec. levels of estrogen (occurs in both sexes); osteoblasts that form new bone have estrogen receptors
- exercise should be regular and high density (weight bearing exercise and resistance is best to inc. bone density at the hip and lumbar spine)
- long bones do NOT shorten with age
- postural changes are evident
- dec. height occurs with shortening of the vertebral column d/t loss of water content and thinning of the intervertebral discs and by a dec. in height of vertebrae from osteoporosis
- progressive dec. in height is not significant until 60 (greater decrease in the 70s and 80s d/t osteoporotic collapse of the vertebrae
- kyphosis –> backward head tilt –> slight flexion of hips and knees
- fat dec. in the periphery and inc. in the abdomen and hips (leaving bony prominences more marked and body hollows more deeper)
- loss in muscle mass, some muscles dec. in size some atrophy and produce weakness
What is bone remodeling?
the cyclic process of bone resorption and deposition responsible for skeletal maintenance at sites that need repair or replacement
** bone resorption (loss of bone matrix) should equal bone replacement but if bone resorption occurs more rapidly, osteoporosis results **
Culture and genetics:
- higher bone mineral density = denser bone
- lower bone mineral density = predictor of hip and vertebral fracture among postmenopausal women
- BMD hip site measurements are higher in Afro-Caribbean, AA and south korean women –> lower r/f fracture
- weight bearing exercise imperative during the reproductive and middle adult years to slow process of decline in BMD
What are some abnormalities found in the joint?
- pain and loss of function
- RA involves symmetric joints
- RA pain is worse in the AM when arising
- OA is worse later in the day
- movement inc. most joint pain BUT in RA, movement dec. pain
- joint pain 10-14 days after an untreated strep throat suggests rheumatic fever
- RA stiffness occurs in the AM and after periods of rest (assess r/f lyme disease)
- dec. ROM may be d/t joint injury to cartilage or capsule or to muscle contracture
- inside knee injury can strain/rupture medial ligaments; outside injury can strain or rupture lateral ligament; abrupt twisting can injure anterior cruciate ligament
- with a knee injury, obtain an x-ray if pt cant flex knee to 90 degrees or unable to bear weight for 4 steps, if pain is felt at fibula head or patella or if the pt is > 55 (ottawa knee rules)
What are some abnormalities found in the muscles?
- myalgia is usually felt as cramping or aching (suggest intermittent claudication)
- ## viral illness often includes myalgia
What are some abnormalities found in the bones?
- fracture causes sharp pain that inc. with movement; other bone pain feels dull and deep and is unrelated to movement
- low back pain occurs w/degenerative discs, osteoporosis, lumbar stenosis or nonspecific
- chronic pain can inc. anxiety
What does a functional assessment assess for?
screens the safety of independent living, the need for HH and QOL
- assess any self care deficit
