Musculoskeletal system Flashcards
Movement
Interaction between sensory, cognitive and motor systems
Sensory system
Sensory infor about body and environment
Cognitive system
Attention, planning, problem solving,motivation
Motor system
Neuromuscular and biomedical systems for movement
Motor Unit
Nerve and all the muscle fibers it innervates
Higher centers of NS
Primary Motor Cortex, Supplemental Motor Area, Premotor cortex, cerebellum, Basal ganglia
Primary motor cortex
Speed and force of movement
Supplemental motor area
Preplanning movements, proactive
Premotor cortex
Visually guided movements
Cerebellum
Coordinates movements for Accuracy, timing and intensity
Basal ganglia
Controls posture and adaptation of varying tasks (feedback)
Prenatal MSK
Develops from mesoderm at 2nd 1/2 of grestation, splitting into myotomes, forms aponeurosis
21 wks: type 1
30 wks: type 2
Infant and Childhood MSK
@ birth 25% of body mass is muscle, increase in strength
Males 2m -16yrs MSK
14x increase in fiber numbers until adolescence
Males 5-17yrs MSK
41-53% increase of fibers
Females 3-10yrs Msk
Peak increase in size
Females 5-17years
41-42% increase of fibers
Adolescence MSK
Fibers at adult levels, growth spurt (muscles lengthen when bones grow), strength increases and endurance
Peak strength
20-30s
Adulthood MSK
Decrease in strength and coordination at 30 (5% decrease each decade), steady decline at 50, 50-70 decrease 30%, rapid decrease at 70.
Older Adults MSK
Sarcopenia: decrease in muscle mass, function, number, and functional units
Senile muscular atrophy: muscle wasting; loss of strength, speed, ans mobility, loss of power (type 2). Decrease reaction time
Epiphyseal lines
Where growth plates have closed
Prenatal skeletal
Develop from mesenchyme
Prenatal 3-8 wks skeletal
Bone and cartilage differentiate and bone develops
Prenatal 5th wks skeletal
Cells condense and differentiate in ue and le
Prenatal 6 wk skeletal
Beginning of Endochondral ossification, chondrocytes form from cartilage
Endochondral Ossification
- Growth cartilage model at 6wks
- Primary ossification center at 7-11wks
- Secondary ossification center after birth (25 yrs
- Articular cartilage and epiphyseal plate after birth
At birth skeletal
Diaphysis ossified (primary), epiphysis still cartilage, primary curves of spine, secondary curves form from walking, sitting against gravity
Infancy and childhood skeletal
Skeletal maturity, bone age tests (hand xray), risser sign (future growth predictions
skeletal Infancy and childhood: Newborn
Head and trunk are disproportionately large, weightbearing drives bone remodeling.
Sutures
Hold bones together
Fontanelles
Soft areas of skull.
Posterior: closes 2-3m
Anterior: 12-18m
Craniosynostis
Premature close of fontanelles
Cranial orthoses
Baby helmets to move head bones
Plageocephaly
Skull forms incorrectly
Adolescence skeletal
Growth continues influenced by hormones ans nutrition, growth spurtts, bones grow first and decreases flexibility
skeletal growth spurts
Girls: 12-14yrs
Boys: 14-15yrs
Older adults
Loss of bone mass, decrease in estrogen, risk of fractures, changes in cartilage, becomes weakened and crack and dry
Estrogen loss per years
Female: 1% decrease per year before menopause, 4% during 4-5 yrs, 1% per year after menopayse
Males: 0.5% per year
Osteopenia
Bone loss due to decreased mineral density
Osteomalacia
Softening of bone
Osteoporosis
Brittle bones, resorption > rebuilding
Prenatal Functional Implications Skeletal
Confined to environment
Club foot, hip dysplasia, limb deficiencies
Infancy and Childhood Functional Implications Skeletal
Growth plate vulnerability, epiphyseal infection and injury, growth plate fracture, apophyseal avulsion, nursemaids elbow
Adolescence Functional Implications Skeletal
Stress fractures, apophyseal avulsion fractures, slipped capital femoral epiphysis (SCFE), scoliosis
Adulthood and older adults Functional Implications Skeletal
Decreased strength endurance, back pain, due to disc changes, osteoporosis, osteoarthritis
Gait cycle
-two phases: stance period and swing period
-stance period: weight acceptance and single limb support
-Swing period: limb advancement
-Weight acceptance: initial contact and loading response
-Single limb support: mid stance and terminal stance
-Limb advancement: pre-swing, initial swing, mid swing, terminal swing
