HOSA Pathophysiology Muscoskeletal

Pathological Bone Fractures

bone breaks because of underlying disease that has weakened the bone

Stress Bone Fractures

bone placed under extreme or unusual forces, MVA, falls, sports injuries are examples

Open Fracture

broken bone end protrudes through skin

closed fracture

no penetration of skin

comminuted fracture

multiple bone fragments

linear fracture

along long axis of bone

oblique fracture

at an angle to long axis of bone

impacted fracture

fragments pushed into each other

spiral fracture

break forms twisted line, torque on bone, spiral fracture of tibia is a common ski injury

transverse fracture

across the long axis

greenstick fracture

partial break

transchondral fracture

through cartilage or growth plate

bone reduction

realign bone fragments to their normal anatomic position

callus formation

healing of fractures, takes from weeks up to 6 months, phagocytes remove cellular debris, osteoblasts synthesize collagen and matrix which mineralizes into a callus

remodeling

healing of fractures, takes several months, callus is replaced with trabeculae (spongy bone), spongy bone is replaced with compact bone

subluxation

partial loss of contact between articular surfaces

dislocation

complete loss of contact between articular surfaces

sprain

a partial tear of a ligament (at a joint), common in the wrist, elbow, ankle and knee

strain

a partial tear of a muscle or its tendon (which can also transverse a joint), sudden forced motion causing the muscle to become stretched beyond its normal capacity (local muscle damage)

avulsion

separation of a tendon or ligament from its bony attachment

tendinopathy

any disease of a tendon, slow to heal, normal organized collagen replaced with weaker, disorganized collagen

epicondylopathy

a type of tendinopathy, where it attaches to a bony epicondyle such as those on the humerus, radius, and ulna

bursitis

inflammation of the bursae, usually caused by repeated trauma such as forceful rubbing of the bursa

septic bursitis

caused by a wound infection

rhabdomyolysis

rapid breakdown of muscle due to severe muscle damage, muscle injury, electric shock, heat stroke, drugs (especially statins) malignant hyperthermia, release of intracellular contents,

malignant hyperthermia

genetic disease that causes a very rapid rise in body temperature in susceptible individuals exposed to certain anesthetics

myoglobinuria

dark urine, causes acute renal failure due to precipitated myoglobin obstructing the renal tubules

compartment syndrome

result of increased pressure with a muscle compartment, fibrous deep fascia surrounds muscle tissue and separates the muscles into compartments. Increased pressure in a compartment results in diminished capillary blood flow, tissue hypoxia, and necrosis

osteoporosis

a disease in which bone tissue is normally mineralized, but the density is decreased and the bone lacks structural integrity, usually asymptomatic until fractures occur

causes of osteoporosis

decreased levels of estrogen and testosterone, decreased activity level, inadequate levels of Vit D, Vit C or Mg++

Osteomalacia

inadequate or delayed mineralization of osteoid, deficiency of vitamin D lowers absorption of calcium from the intestines, osteoid is laid down, but calcification does not occur (soft bones)

s/s of osteomalacia

pain bone fractures, (esp. hip fracture), vertebral collapse, and bony malformations

rickets

osteomalacia in children

PDB (Paget's Disease of the Bone) or Osteitis Deformans

cause is unknown but it results in a state of increased metabolic activity (excessive bone remodeling). Manifested by disorganized, thickened but soft bones, most lften affext the axial skeleton, thickened bones can cause abnormal bone curvatures, brain and nerve compression, impaired motor function and deafness

osteomyelitis

bone infection, most often caused by a S. aureus infection, open wound is most common, but it can also be caused by a blood-borne infection.

s/s osteomyelitis

acute and chronic inflammation, fever, pain and necrotic bone

tx for osteomyelitis

antibiotics, debridement, surgery, and hyperbaric oxygen therapy

arthropathies

a group of diseases which destroy the joints, differentiated by the absence or presence of synovial membrane inflammation, the presence or absence of systemic s/s, the findings from synovial fluid analysis

osteoarthritis

degenerative joint disease, atypical inflammatory process, primary defect is loss of articular cartilage, leaving underlying bone unprotected, results in sclerosis of the underlying bone and formation of bone spurs

osteophytes

bone spurs

s/s osteoarthritis

pain, stiffness, enlargement, tenderness, limited range of motion and deformity

rheumatoid arthritis

chronic, systemic, inflammatory autoimmune disease, the prototypical inflammatory joint disease, affects more women than men

s/s rheumatoid arthritis

s/s similar to osteoarthritis, synovial fluid will be very different, presence of rheumatoid factors (RF tests), elevated ESR (erythrocyte sedimentation rate), joint fluid presents with inflammatory exudate, nodules (necrotic areas) on the bones

symmetric arthritis

morning joint stiffness lasting at least one hour, swelling of soft tissue around 3 or more joints, radiographic evidence of erosions in the joints of the hands

gout and gouty arthritis

abnormal metabolism of purine nucleotides (adenine, guanine( resulting in accumulation and elevation or uric acid in the blood and body fluids, which eventually precipitate and form crystal deposits, triggering the acute inflammatory response

hyperuricemia

elevation of uric acid in the blood

tophi (urate crystal granuloma)

subcutaneous nodules that form from crystal deposition

secondary muscle dysfunction

muscular symptoms arising from a variety of causes, some unrelated to the muscle itself, i.e. contractures, stress-induced muscle tension, disuse atrophy

physiologic contractures

muscle fiber shortening without an action potential, ie malignant hyperthermia, caused by a failure of the calcium pump to replace calcium in the sarcoplasmic reticulum

pathologic contractures

muscle fiber shortening caused by muscle spasm or weakness, i.e. muscle dystrophy, spinal cord injury, heel cord contractures

stress-induced muscle tension

neck stiffness, back pain, clenching teeth, hand grip and HA, caused by an increase activity of the RAS (reticular activating system), chronic anxiety

disuse atrophy

reduction in muscle and the normal size of muscle cells due to prolonged inactivity and muscle deconditioning

causes of disuse atrophy

bed rest, trauma, casting, nerve damage

tx of disuse atrophy

isometric movements and muscle-lengthening exercises

fibromyalgia

chronic, non-inflammatory musculoskeletal syndrome, diffuse, chronic pain, tender points are found in predictable patterns, etiology is unknown: suspects include viral illness, certain meds, physical or emotional trauma

s/s fibromyalgia

vague symptoms: increased sensitivity to touch, fatigue and sleep disturbances. Often misdiagnosed as chronic fatigue syndrome