Patho: Musculoskeletal

T or F: the origin of joint stiffness is unknown in OA

TRUE

Are boys or girls affected by idiopathic congenital equinovarus more often?

boys

How might OA of the lower cervical spine present?

brachial neuralgia - aggravated by movement of the neck

How is calcium involved with the relaxation phase of muscle function?

calcium is pumped back into the sarcoplasmic reticulum by means of an active transport process

What is thought to be the primary target for the immune response in AS?

cartilage

What is pseudogout?

caused by the formation of calcium pyrophosphate dihydrate crystals

What is the proposed mechanism of adolescent scoliosis?

central nervous system issue involving the balance mechanism

What factor is directly correlated with hydroxyapatite crystal deposition in OA?

chondrocyte apoptosis

What are the fragments of articular cartilage digested by?

chondrocytes - digested by the cell's own lysosomal enzymes

What are the methods of reducing a fracture?

closed manipulation traction open reduction

What is positional equinovarus?

club foot in which the deformity can be passively corrected without surgical intervention

What is idiopathic congenital equinovarus?

clubfoot without a known etiology

What is a complete vs. incomplete fracture?

complete = all the way through incomplete = bone is still in one piece, not all the way through

What might cause in impacted fracture?

compressive axial energy or force directly to distal fragment

What does coupling consist of?

consists of migration of calcium ions to the myofilaments

What are tophi?

crystal deposition in subcutaneous tissues that are small, white nodules visible through the skin

What are some causes of tendinopathy?

crystal deposits postural misalignment hypermobility of a joint

What is involved with medial epiconylopathy or "golfer's elbow"?

degenerative process of the pronator teres, flexor carpi radialis and palmaris longus tendons at the medial humeral condyle

What initiates the second stage of muscle contraction?

depolarization of the T-tubules - to initiate coupling

What is the degree of deformity measured by in metatarsus adductus?

determined by the heel bisection line

When do the clinical manifestations of OA appear?

during the fifth or sixth decade of life

What is pain early in RA caused by? Late in RA?

early = pressure from swelling late = sclerosis of subchondral bone and new bone formation

What exactly hardens the woven bone callus?

enzymes increase the phosphate content and permit the phosphate to join with the calcium to be deposited as mineral to harden the callus

What is the first stage of muscle contraction?

excitation

What is nonunion?

failure of the bone ends to grow together

What is the etiology of flexible flatfoot deformity?

familial

What are some risk factors for DDH?

family history female gender metatarsus adductus torticollis oligohydramnios first pregnancy breech presentation

What is a subluxated hip in DDH?

hip maintains contact with the acetabulum but is not well seated within the hip joint

What must also be evaluated when metatarsus adductus is diagnosed?

hips for DDH

What is the rate of protein synthesis in the human body related to?

hormone levels (insulin) amino acid substrates overall nutritional status

What are the factors that influence gout?

hyperuricemia older age genetic predisposition excessive alcohol consumption obesity drugs lead toxicity

What results as a consequence of compromised circulation in RA?

hypoxia and metabolic acidosis - stimulates the release of hydrolytic enzymes from synovial cells into surrounding tissue

Where is pain generally localized with symptomatic tendinopathy?

localized over the involved tendon and movement in the affected joint is limited

What does the pannus in RA act like?

locally invasive tumor of the synovium

The loss of what is the primary defect in OA?

loss of articular cartilage (progressive)

What is the hallmark of the osteoarthritic process?

loss of proteoglycans from the articular cartilage

How is articular cartilage lost in OA?

lost through a cascade of cytokine and anabolic growth factor pathways

What are central joints most often affected by OA?

lower cervical spine, lumbosacral spine, shoulders an hips

What natural curvatures are lost as AS progresses?

lumbar lordosis is straightened and thoracic kyphosis is accentuated

Where can rheumatoid nodules atypically occur?

lungs (Caplan syndrome) heart spleen blood vessels

What is broken down as the joint space is infiltrated by matrix metalloproteinases in OA?

macromolecules of proteoglycans, glycosaminoglycans and collagen

Are males or females more likely to get AS?

males (10x more likely)

What is the peak age of onset in gout?

males 40-50 years old - later in females

What is cartilage destruction of RA mediated by?

matrix metalloproteinases that activate the synoviocytes to invade and attack the synovium and matrix

What are some results of a strong pull occurring too soon in a ligament or tendon tear?

may separate again or excessive amounts of scar tissue may render the tendon or ligament functionless

Where do greenstick fractures most commonly occur?

metaphysis or diaphysis of the tibia, radius and ulna

What is the most common foot deformity found in children?

metatarsus adductus

What type of injury will elicit the bone remodeling process?

microscopic bone injuries - fractures and surgical wounds heal the same as soft tissue injuries

What might be the cause of an occult fracture?

minor force or energy - a fracture that is hidden or not readily discernible

What type of crystal is deposited in connective tissues throughout the body in gout?

monosodium urate

When do most dysplasias occur in gestation and what are they the result of?

most often occur in 2nd and 3rd trimester - result of positioning factors

What is the prime mover of a muscle?

muscle agonist

What might subsequent pain of a fracture be caused by?

muscle spasm, overriding of the fracture segments or damage to adjacent soft tissues

What stimulates an intense inflammatory response right when a bone breaks?

necrotic bone tissue directly adjacent to the fracture site

What is the time frame of when hematoma, procallus and callus formation occur?

1. hematoma - within hours of a fracture 2. procallus - within days of a fracture 3. callus - within weeks 4. replacement and contour - within years

What are the bone stages of wound healing?

1. hematoma formation 2. procallus formation 3. callus formation 4. callus replacement 5. remodeling

What is joint effusion caused by in OA?

1. presence of osteophyte fragments in the synovial cavity 2. drainage of cysts from diseased subchondral bone 3. acute trauma to joint structures, resulting in hemorrhage and inflammatory exudation into the synovial cavity

What does the speed of bone healing depend upon?

1. severity of bone disruption 2. type and amount of bone tissue that must be replaced 3. blood supply and oxygen content at the site 4. presence of growth and thyroid hormones, insulin, vitamins and other nutrients 5. presence of systemic disease 6. effects of aging 7. effectiveness of treatment

What are some of the proposed mechanisms of OA?

1. subchondral bone changes 2. weightbearing stress 3. inflammatory mediators

What are the specific risk factors of OA?

1. trauma 2. long term mechanical stress 3. presence of inflammation 4. joint instability 5. neurologic disorders 6. congenital or acquired skeletal deformities 7. hematologic or endocrine disorders 8. drugs 9. obesity

How much is the need for ATP increased during activity?

100x

How much will maximal exercise increase oxygen uptake?

15-30 times over the resting state

How long is skeletal maturation delayed in children with LCP disease?

2 years

What is bone remodeling?

3 phase process in which existing bone is reabsorbed and new bone is laid down to replace it

At what age is LCP most common?

3-10 years old (in boys)

How long does the initial inflammatory phase of healing last?

3-4 days

How long does the entire process of bone remodeling take place?

3-4 months

How long does a healing tendon or ligament lack strength to withstand a strong pull?

4-5 weeks post injury

What percentage of OA of the hip might be related to DDH?

60%

At what degree will a lateral spine curvature result in decreased pulmonary function?

80 degrees

What do urate crystals react with specifically in the joint fluid?

neutrophils and monocytes

What factor stimulates apoptosis in chondrocytes in OA?

nitric oxide

Is OA characterized as inflammatory or non-inflammatory joint disease?

non-inflammatory

What might an improper reduction or immobilization of a fracture result in?

nonunion delayed union malunion

What temperature do muscles work best at?

normal body temperature

What is the treatment for asymptomatic flexible pes planus?

nothing!

When does collagen formation occur after a sprain or strain?

occurs 3-4 days after the injury

What is the time frame for joint stiffness in OA?

occurs with joint movement and dissipates after 30 minutes

What happens to the haversian systems in phase three of bone resorption?

old haversian systems are desteroyed and new haversian systems are formed

Where does the pathology of OA most commonly take place?

on load-bearing areas

Where in the bone are bone precursor cells located?

on the free surfaces of bones and along the vascular channels (especially the marrow cavities)

What is a common age-related disorder of synovial joints?

osteoarthritis

What occurs during callus replacement?

osteoblasts continue to replace the callus with lamellar bone or trabecular bone

What occurs during the callus formation of wound healing?

osteoblasts in the procallus form membranous or woven bone

What occurs during secondary bone formation (phase 3)?

osteoblasts line the walls of the resorption cavity lamellae in compact bone are laid down

What are fractures of the upper femur, upper humerus, vertebrae and pelvis most commonly associated with?

osteoporosis

What typically causes bursitis?

overuse or excessive pressure on a bursae

What is an indirect measure of energy expenditure?

oxygen consumption

What is the first symptom of OA?

pain and stiffness in one or more joints

Why are stress fractures painful?

painful because of accelerated remodeling - not because of trauma

What occurs during the remodeling stage of bone healing?

periosteal and endosteal surfaces of the bone are remodeled to the size and shape of the bone before injury

What is the formation phase of bone remodeling?

phase 3 - secondary bone formation

What occurs when a motor unit responds to a single nerve stimulus?

phasic contraction = also called a twitch

What occurs when the anaerobic threshold is reach and more oxygen is required

physiological changes occur - 1. increase in lactic acid concentrations 2. increase in oxygen consumption 3. heart rate 4. respiratory rate 5. muscle blood flow

What is a common cause of heel bursitis?

poorly fitting footwear

Who does osgood-schlatter most commonly occur in?

preadolescent and adolescents who participate in sports

At what age does acute bursitis most often occur?

primarily in the middles years and is often caused by trauma

What stage of healing do enzymes and growth factors aid in (like insulin, bone morphogenic protein and osteogenin)?

procallus formation

What is the position of a bone segment (post fracture) determined by?

pull of attached muscles, gravity, direction and magnitude of the force that caused the fracture

What is uric acid a breakdown product of?

purine nucleotides

What factor allows the muscles to activate the number of motor units to generate the desired force?

recruitment and repetitive discharge

What is the last step of muscle function?

relaxation

What is the fourth stage of LCP disease?

remodeling takes place and newly formed bone is organized into live spongy bone

What is an extremely common finding in conjunction with gout?

renal stones

What are fractures of healthy bones like the tibia, clavicle and lower humerus caused by?

result of trauma

What is nonstructural scoliosis?

results from a cause other than the spine itself, such as posture, leg length discrepancy or pain

In what disease might the joint space feel swollen and "boggy" with the sin having a ruddy or cyanotic hue?

rheumatoid arthritis

In what joint disease does the synovial membrane undergo hyperplastic thickening?

rheumatoid arthritis

What is a chronic, systemic inflammatory autoimmune disease distinguished by joint swelling, tenderness and destruction of synovial joints, leading to disability and premature death?

rheumatoid arthritis

What joint disease is potentially linked to a defect in telomere repair that may result in faster again of telomeres?

rheumatoid arthritis

What are the primary ion channels that control calcium release?

ryanodine receptors (RyRs) - intracellular receptors within skeletal muscle sarcoplasmic reticulum

What is a fracture in which a bone breaks into more than 2 pieces?

segmented

What is LCP disease?

self-limited disease of the hip that is produced by recurrent interruption of the blood supply to the femoral head

What is the primary function of a bursae?

separate, lubricate and cushion tendons, muscles and bony prominences

What are the common sites of bursitis?

shoulder (subacromial) elbow (olecranon) hip (greater trochanter) ischial knee heel

What is epicondylopathy related to?

smoking, obesity, work activities that involve forceful and repeptitive cyclic flexion and extension

What occurs in the initial stage of LCP disease?

soft tissues of the hip are swollen, edematous, and hyperemic with fluid - the joint space widens and the capsule bulges

What is a dislocatable hip in DDH?

sometimes located by can be dislocated easily - dislocated hip has no contact between the femoral head and the acetabulum

What are common causes of teratologic equinovarus?

spina bifida, diastrophic dwarfism

What are ligament tears known as?

sprains

What are joint mice?

spur-like bony projections that break off into the synovial cavity as seen in OA

What is converted anaerobically to sustain brief muscular activity?

stored glycogen and blood glucose

Which enzymes are markedly elevated in osteoarthritis?

stromelysin and matrix metalloproteinases

As the subchondral bone becomes unprotected in OA, what occurs?

subchondral bone becomes sclerotic (dense and hard)

What is an open reduction?

surgical procedure that exposes the fracture site and is brought into alignment under direct visualization

What is the first joint tissue to be affected in RA?

synovial membrane (lines the joint cavity)

What is inflammation of tendons known as?

tendinitis

What does the term tendinopathy include?

tendinitis, tendinosis and parateninitis

What is the painful degradation of collagen fibers known as?

tendinosis

What is repetitive discharge?

the adding of motor units within a muscle

What is oxygen debt?

the amount of oxygen needed to convert the buildup of lactic acid to glucose and replenish ATP and phosphocreatine stores

How does water affect the cartilage in OA?

the cartilage absorbs more water, due to disregulation of the proteoglycan pump

What is the third stage of LCP disease?

the dead formal head is replaced by a procallus (collapse and flattening of the femoral head is seen)

What provides osteoclasts with information about where to begin resorbing damaged bone in phase 1?

the distribution of apoptotic osteocytes - portion of the bone that dies

What is the second stage of LCP disease?

the entire epiphysis or anterior half of the epiphysis of the femoral head loses blood supply and the epiphyseal plate is softened

What does successful regeneration of skeletal muscle fibers depend upon?

the extent of the injury, preservation of vascular supply, availability of satellite cells and terminal axons for reinnervation

What is the cross-bridge theory?

the formation of the actin-myosin cross-bridges that releases ATP when attached

How is the foot positioned in clubfoot?

the heel is positioned varus and plantar flexed

What is the most common site for tophi?

the helix of the ear

Where is most uric acid eliminated from in the body?

the kidneys

Where is pain most commonly referred in LCP disease?

the knee, inner thigh and groin

What is a syndesmophyte?

the new enthesis of bone which forms on top of the old enthesis - give AS the classic "bamboo spine" appearance

What is phase 2 of bone remodeling?

the osteoclasts form a "cutting cone" which gradually resorbs bone, leaving behind and elongated cavity (resorption cavity)

What is an inflammasome?

the product of a macrophage trying to phagocytize MSU crystals in gout

Over time, what factor decreases in direct proportion to the severity of OA?

the quality and quantity of proteoglycans

What does the excitation stage of muscle contraction begin with?

the spread of an action potential from the nerve terminal to the neuromusclular junction

What is the total force developed in a muscle contraction?

the sum of the force generated by each motor unit

What is pannus?

the thick granulation tissue that synovium is converted into through the interaction of TNF-a and fibroblasts

What portion of the tibia is affected in osgood-schlatter disease?

the tubercle of the tibia

How do neutrophils and macrophages contribute to RA?

these phagocytes are drawn into the synovial membrane and ingest immune complexes - in doing so they release enzymes that degrade synovial tissue and articular cartilage

What is the function of troponin and tropomyosin in the stage of muscle contraction?

they are muscle proteins that bind with actin when the muscle is at rest

What is most tendon pathology caused by?

tissue degeneration rather than inflammation

What is initial pain of a fracture generally caused by?

trauma

What hormones does calcium affect in the coupling stage of muscle contraction?

troponin and topomyosin

What is the primary pathologic problem in AS?

uncontrolled bone formation

What is the key symptomatic feature of OA?

use-related joint pain relieved by rest

When and where is the pain of gout usually noticed?

usually noticed at night - 50% involve the MTP joint of the great toe

What are some extra-articular changes that can accompany AS?

uveitis fibrotic changes in lungs cardiomegaly aortic incompetence amyloidosis Achilles tendinitis

How are nerves and vessels affected in tendinopathies?

vascular and nerve ingrowth occurs - facilitating pain transmission (especially in Achilles and patellar tendinopathies)

When do bowing fractures usually occur?

when a longitudinal force is applied to bone

When does contraction of a muscle begin?

when calcium ions combine with troponin

When does a rupture of the Achilles tendon occur?

when forced dorsiflexion is applied to the foot when it is in plantar flexion

When is skin traction used?

when only a few pounds of pulling force are needed to realign the fragments of when the traction will be used for brief times only

When is maximum force generated in muscle contraction?

when the actin and myosin filaments have maximum interactions

When is ATP released in contraction?

when the actin-myosin complex is cross bridged with other actin-myosin complexes

When is closed manipulation used?

when the contour of the bone is in fair alignment and can be maintained well with immobilization

When does the relaxation phase begin?

when the sarcoplasmic reticulum absorbs the calcium molecules, removing them from interaction with troponin

What is muscle tetanus?

when the summation of contraction is reached where no further increase in force can be achieved

Where do ligament tears most commonly occur?

wrist, ankle, elbow and knee joints

Is movement of the joint normal in bursitis?

yes!!!

What is the highest incidence of fractures?

young males between 15-24 years old adults 65 years or older

What are the four-steps of muscle contraction?

1. excitation 2. coupling 3. contraction 4. relaxation

What are two complications of chronic RA?

1. formation of cysts in the articular cartilage or subchondral bone 2. rupture of a cyst or of the synovial joint itself

What is the electrical charge of the plasma membrane at rest?

-90mV - continually aintained across the sarcolemma

What are the three ways in which a buildup of uric acid can occur?

1. accelerated rate of purine synthesis with overproduction of uric acid 2. break down of purine nucleotides at an accelerated rate that also results in an overproduction of uric acid 3. deficiency of enzyme HGPRT

What are the three phases of bone remodeling?

1. activation 2. resorption 3. formation

What is the progression of articular cartilage loss in OA?

1. articular cartilage loses its glistening appearance - becomes yellow-gray 2. articular cartilage flakes off and deeper layers develop longitudinal fissures 3. cartilage becomes thin and may be absent over areas 4. subchondral bone becomes sclerotic

What are the three clinical stages of gout?

1. asymptomatic hyperuricemia 2. acute gouty arthritis 3. tophaceous gout

In which arthritic disease is back pain alleviated by movement and worsened by rest?

AS

What substances are necessary to fuel the complex processes of muscle contraction?

ATP and phosphocreatine

What might be the issue with a painful pes planus?

Achilles contracture or tarsal coalition

T or F: pain of OA is correlated with the radiological appearance of OA

FALSE!

Which enzyme is needed to break down uric acid?

HGPRT

What gene is highly associated with AS?

HLA-B27

What are the two gene defects that are commonly found among patients with RA?

HLA-DR4 and HLA-DP genes

Which inflammatory cytokines play a major role in cartilage degredation through the induction of nitric oxide synthase and nitric oxide?

IL-1 and TNF

What are the two immunoglobulin antibodies that are most commonly rheumatoid factors?

IgM and IgG

What is the most common sign of early AS?

LBP and stiffness

What might mimic sciatic pain?

OA of the lumbosacral spine

What is the method used for passively correcting idiopathic conginital equinovarus?

Ponseti technique - use of serial casting and then bracing until age three

What is activated in RA in order to promote osteoclast formation, causing bony erosion?

RANKL

What are bone remodeling units made up of?

bone precursor cells that differentiate into osteoclasts and osteoblasts

Who are incomplete fractures more common in?

bones of growing children

What is a pathological fracture?

a break at the site of a preexisting abnormality - such as a tumor

What is a fracture?

a break in the continuity of a bone

What is a torus fracture?

a buckle fracture in which the cortex buckles but does not break

What is structural scoliosis?

a curvature of the spine associated with vertebral rotation

What is a type of stress fracture that is a caused by abnormal stress or torque applied to a bone with normal ability to recover?

a fatigue fracture

What is a transchondral fracture?

a fracture that consists of fragmentation and separation of a portion of the articular cartilage that covers the end of a bone at a joint

What is a fragility fracture?

a fracture that results from a low-level trauma (one that would not normally cause a fracture) as seen in osteoporosis

What occurs during skeletal traction?

a pin or wire is drilled through the bone below the fracture site and a traction bow, rope and weights are attached to the pin or wire to apply tension and provide the pulling force needed to overcome the muscle spasm

What is aggrecan?

a proteoglycan that forms a major part of the extracellular matrix of cartilage and helps maintain its stability - possibly a causative agent for AS

What is a tear in a tendon known as?

a strain

What is a delayed union?

a union that does not occur until 8-9 months after a fracture

What is an avulsion a result of?

abnormal stress on the ligament or tendon - commonly seen in young athletes - sprinters, hurdlers and runners

What are fractures of the hands and feet usually caused by?

accidents in the workplace

What is positive muscle work?

accomplished during muscle shortening - the energy is released to exert force or lift a weight

What are the filaments that aid in muscle contraction?

actin (thin filament) and myosin (thick filament)

What is phase 1 of the bone remodeling cycle?

activation - occurs when a stimulus activates programmed cell death (apoptosis)

Who are transchondral fractures mostly prevalent in?

adolescents

When is the pain of osgood-schlatter most severe?

after physical activity that involves vigorous quadriceps contraction

When might calcium be deposited in the tendon origin area?

after repeated bouts of inflammation from tendonitis

What is the pain of OA aggravated and alleviated by?

aggravated by movement alleviated by rest

Where are trabeculae formed after a bone fracture?

along lines of stress - where unnecessary bone callus is resorbed

What are rheumatoid factors?

altered antibodies that become autoantibodies - antibodies that attack host tissues

What is a chronic inflammatory joint disease characterized by stiffening and fusion of the spine and SI joints?

ankylosing spondylitis

Which tendon is affected in osgood-schlatter disease?

anterior patellar tendon

What is OA caused by?

any condition that damages cartilage directly

What amino acid is modified to contribute to the pathogenesis of RA?

arginine --> citrulline

What is a proposed mechanism for the joint pain associated with RA?

articular distension and stretching of the fibrous joint capsule (with abundant nerve supply) fibrous shrinking so that movement is painful in any direction

What is a complete separation of a tendon or ligament from its bony attachment?

avulsion

Where does enzymatic destruction of articular cartilage begin?

begins in the matrix with the destruction of proteoglycans and collagen fibers

How is blood flow to a fracture site affected days after a fracture?

blood flow is increased within 48 hours of an injury

What occurs as synovial inflammation progresses to involve blood vessels and small venules in RA?

blood vessels and venules become occluded by the hypertrophied endolthelial cells, fibrin, platelets and inflammatory cells which decrease vascular flow to the synovial tissue

What ultimately forces the muscle to reduce activity?

fatigue and weakness due to the inability to respond to the need for ATP and the subsequent buildup of lactic acid

What are some other issues that RA might cause?

fever, malaise, rash, lymph node or spleen enlargement, Raynaud phenomenon

What is a procallus composed of?

fibroblasts, capillary buds and osteoblasts

What cartilage is primary involved in AS?

fibrocartilage in cartilaginous joints (vertebrae)

What are the joints most commonly affected by RA?

fingers, feet, wrists, elbows, ankles and knees

When will hematoma formation occur in the stages of wound healing?

first if vessels have been damaged causing hemorrhage

What is pes planus?

flat feet - generally benign

What type of contractures are common in RA?

flexion contractures

Where is calcium transported to and from when a muscle is in the contraction phase?

from the sarcoplasmic reticulum to the myofibril

What are some environmental factors that influence the development of RA?

geographic area of birth length of breast-feeding socioeconomic status smoking

What is a syndrome caused by an inflammatory response to uric acid production?

gout

What components surround soft tissue and cartilage when a ligament or tendon in torn?

granulation tissue with macrophages, fibroblasts and capillary buds

What type of fracture occurs when the outer surface is disrupted, but the inner surface remains intact?

greenstick fracture

What are the most often injured tendons in the body?

hands, feet, knee, upper arm, thigh, ankle and heel

What are peripheral joints most commonly involved in OA?

hands, wrists, knees and feet

What is a malunion?

healing of a bone in a nonanatomic position

How is energy expenditure directly measured?

heat production - heat is released whenever work is accomplished

What are some treatments for delayed union and non union?

implantable or external electric current devices, electromagnetic field generations, low density ultrasound to stimulate bone formation

When might a false joint or pseudarthrosis be visible?

in a nonunion

When might a spontaneous tendon rupture occur?

in an individual receiving local corticosteroid injections, fluoroquinolones and in personds with rheumatoid arthritis or SLE

Where are rheumatoid nodules most commonly found?

in subcutaneous tissue over the extensor surfaces of elbows and fingers

Where do the earliest pathologic changes occur in scoliosis?

in the muscles, ligaments and other soft tissues that become shortened

How is idiopathic scoliosis classified?

infantile, juvenile or adolescent - depending on the child's age at the time of onset

What is bursitis?

inflammation of bursal sacs

What is epicondylitis?

inflammation of the tendon where it attaches to a bone (at the origin)

What is the first thing that happens after a tendon or ligament is torn?

inflammatory exudate develops between the torn ends

What are the inflammatory components that are released in response to bone necrosis after a fracture?

inflammatory leukocytes mast cells TF-B PDGF prostaglandins

What does the rapid depolarization of the membrane initiate in muscle fiber contraction?

initiates an electrical impulse in the muscle fiber membrane called the muscle fiber action potential

How does the onset of RA generally begin?

insidiously - with fever, fatigue, weakness, anorexia and weight loss

What are fragility fractures of osteoporosis or osteomalacia known as?

insufficiency fractures

What are the immunoregulatory cytokines that contribute to joint damage in RA?

interleukins B cells matrix metalloproteinases

What is believed to cause metatarsus adductus?

intrauterine positioning

What is isotonic contraction?

involves the lengthening or shortening of a muscle

What type of contraction occurs when a muscle maintains constant length as tension is increased?

isometric contraction

What is difficulty in initiating joint movement, immobility or a loss of range of motion?

joint stiffness

What are Heberden and Bouchard nodes?

joint swelling of OA in the fingers

When does primary AS usually develop?

late adolescence or young adulthood

What is degeneration or irritation of the extensor carpi radialis brevis tendon?

lateral epicondylitis

Which hip is most commonly affected in DDH?

left hip

What is Galeazzi sign?

limb length discrepancy seen in DDH

What are the ways in which fractures are classified along a fracture line?

linear fracture oblique fracture spiral fracture transverse fracture

What is osteoarthritis characterized by?

local areas of less and damage of articular cartilage, new bone formation of joint margins (osteophytosis), subchondral bone changes, variable degrees of mild synovitis, thickening of the joint capsule