Musculoskeletal/Integument Ch.38, 39, 40, 41, 42

What is the characteristic lesion of erythema multiforme?

"bull's-eye," or "target," lesions occur on the skin surface with a central erythematous region surrounded by concentric rings of alternating edema and inflammation."bull's-eye," or "target," lesions occur on the skin surface with a central erythematous region surrounded by concentric rings of alternating edema and inflammation.

What are the stages of bone wound healing?

1. Inflammation/hematoma formation 2. Procallus formation 3. Callus formation 4. Replacement, by basic multicellular units, of the callus with lamellar or trabecular bone 5. Remodeling of the periosteal and endosteal surfaces of the bone to the size and shape of the bone before injury

How does osteomyelitis develop?

Acute hematogenous osteomyelitis is the most common form in children. The infection usually begins as an abscess in the metaphysis of a long bone where blood flow is sluggish and bacteria can collect. 1042With increasing pressure, the infection will rupture out of the periosteum and spread along the diaphysis of the bone. A new shell of bone can develop under the elevated periosteum and can become an involucrum. The portion of bone that is separated from adequate blood supply by the infection can die, thereby leading to an involucrum.

What is alopecia? Compare the different types.

Alopecia means loss of hair from the head or body. Androgenic alopecia is localized hair loss; genetically predisposed response to androgens; Male-pattern baldness begins with frontotemporal recession and progresses to loss of hair over the top of the scalp. Female-Pattern Alopecia - progressive thinning and loss of hair over the central part of the scalp; there is usually no loss of hair along the frontal hairline but the hairs are shorter and thinner. Alopecia areata is an autoimmune T-cell-mediated chronic inflammatory disease directed against hair follicles and results in hair loss; rapid onset of hair loss in multiple areas of the scalp, usually in round patches. The eyebrows, eyelashes, beard, and other areas of body hair are rarely involved.

How do the skin blood vessels and sweat glands regulate body temperature?

Arteriovenous anastomoses in the dermis facilitate the regulation of body temperature. Heat loss is regulated by (1) variations in skin blood flow through the opening and closing of arteriovenous anastomoses and (2) the evaporative heat loss of sweat. The sympathetic nervous system regulates both vasoconstriction and vasodilation through α-adrenergic receptors in the skin.

Describe significant changes in the musculoskeletal system with aging.

Bones become less dense, less strong, and more brittle; bone remodeling cycle takes longer, rate of mineralization also slows; women experience loss of bone density, accelerated with the rapid bone loss during early menopause from increased osteoclastic bone resorption, fewer osteocytes, and decreased numbers of osteoblasts; Men experience bone loss also but at later ages and much slower rates than seen in women; Stem cells in the bone marrow perform less efficiently; cartilage becomes more rigid, fragile, and susceptible to fraying because of increased cross-linking of collagen and elastin, decreased water content in the cartilage ground substance, and reduced concentrations of glycosaminoglycans; Decreased range of motion of the joint; Bones in joints develop evidence of osteoporosis with fewer trabeculae and thinner, less dense bones; Intervertebral disk spaces decrease in height. Tendons shrink and harden. reduced mitochondrial volume; muscle mass and strength decline slowly; The amount of type II fibers also decreases. reduced synthesis of RNA, loss of mitochondrial function, and reduction in the size of motor units. regenerative function of muscle tissue remains normal; skeletal muscle mass and strength may be lost; Muscle fatigue may contribute to loss of function; progressive neuromuscular changes and diminishing levels of anabolic hormones; decline in the synthesis of mixed proteins, myosin heavy chains, and mitochondrial protein. Maximal oxygen intake declines. Basal metabolic rate is reduced and lean body mass decreases

What is the difference between Becker and Duchenne muscular dystrophies?

Children with BMD present later and have a longer life expectancy than those with DMD

What malignancy can arise from melanocytes?

Cutaneous melanoma

What disorders of the nail are seen?

Paronychia is an acute or chronic infection of the cuticle. Onychomycosis (tinea unguium) is a fungal or dermatophyte infection of the nail unit.

Describe the inflammatory lesion associated with lupus erythematosus.

butterfly pattern of distribution found over the nose and cheeks. lesions may be single or multiple and vary in size. Often the lesions are located on light-exposed areas of the skin, and photosensitivity is common. early lesion is asymmetric, with a 1- to 2-cm raised red plaque with a brownish scale.

What are the causes associated with osteoporosis in women and men?

declining levels of estradiol and androgen, inadequate dietary calcium intake, decreases in weightbearing exercise, and sarcopenia, increasing age, Low bone mineral density, hypogonadism, early menopause, smoking, hyperparathyroidism, RA, diabetes, corticosteroids, methotrexate, alcoholism

Describe the two layers of the skin.

(1) a superficial or outer layer of epidermis - Most important layer of skin; normally very thin (0.12 mm) but can thicken and form corns or calluses with constant pressure or friction; includes rete pegs that extend into papillary layer of dermis (2) a deeper layer of dermis (the true skin) -Irregular connective tissue layer with rich blood, lymphatic, and nerve supply; contains sensory receptors and sweat glands (apocrine, eccrine, sebaceous), macrophages (phagocytic and important for wound healing), and mast cells (release histamine and have immune functions)

Compare five major characteristics of benign bone tumors with those of malignant bone tumors.

(1) an increased nuclear/cytoplasmic ratio, (2) an irregular nuclear border, (3) an excess of chromatin, (4) a prominent nucleolus, and (5) an increase in the number of cells undergoing mitosis

What causes the inflammation of acne vulgaris

(1) hyperkeratinization of the follicular epithelium, (2) excessive sebum production, (3) follicular proliferation of anaerobic Propionibacterium acnes, and (4) inflammation and rupture of a follicle from accumulated debris and bacteria

How does juvenile idiopathic arthritis differ from the adult form?

1. Large joints are most commonly affected. 2. Chronic uveitis (inflammation of the anterior chamber of the eye) is common if the blood test for antinuclear antibody (ANA) is positive; slit lamp examination by a trained ophthalmologist is required every 6 months to avoid vision loss. 3. Serum tests may be negative for rheumatoid factor (RF); RF-positive children have a worse prognosis. 4. Subluxation and ankylosis may occur in the cervical spine if disease progresses. 5. Rheumatoid arthritis that continues through adolescence can have severe effects on growth and adult morbidity.

Describe the three degrees of burn injury.

1st-Destruction of epidermis only; local pain and erythema ; skin fx intact; no blisters after first 24 hr; Skin peels at 24-48 hr; normal or slightly red underneath; heals 3-5 days, no scar 2nd - superficial partial thickness -Destruction of epidermis and some dermis; skin fx absent; blisters Present within minutes; thin walled and fluid filled; Red to pale ivory, moist surface; heals 21-28 days, scar May be present; deep partial thickness - Destruction of epidermis and dermis, leaving only skin appendages; blisters May or may not appear as fluid-filled blisters; often is layer of flat, dehydrated tissue paper-like skin that lifts off in sheets; Mottled with areas of waxy, white, dry surface heals 30 days to many months, scars Highest incidence because of slow healing rate promoting scar tissue development 3rd-full thickness; Destruction of epidermis, dermis, and underlying subcutaneous tissue; Blisters rare; usually is layer of flat, dehydrated tissue paper-like skin that lifts off easily; White, cherry red, or black; may contain visible thrombosed veins; dry, hard, leathery surface; Will not heal; may close from edges as secondary healing if wound is small; Skin graft; scarring minimized by early excision and grafting; 4th-Full Thickness and Deeper Tissue-Destruction of epidermis, dermis, and underlying subcutaneous tissue, tendons, muscle, and bone;Black and charred appearing wound; Will not heal; requires skin grafting; may require amputation and/or reconstructive surgery; Degree of scarring associated with reconstruction and grafting success

Distinguish the differences between sprains, strains, tendonitis, epicondylitis, and bursitis.

A tear in a tendon is known as a strain a tear in a ligament is called a sprain Tendonitis caused by Trauma, crystal deposits, postural misalignment, and hypermobility. common at Achilles epicondylitis caused by overuse. common at Humerus, radius, ulna, knee bursitis caused by Trauma, repeated trauma, overuse, excessive pressure. common at Shoulder, hip, knee, elbow

What is the most common skin cancer?

Basal cell carcinoma (BCC)

Enhance your knowledge of the different musculoskeletal tumors, their pathophysiology, and their treatment.

Bone- Osteosarcoma, Chondrosarcoma fibrosarcoma, Giant cell tumor, Myeloma; patho: Neoplasms of the bone can arise from bone cells themselves or from supportive tissues such as cartilage, fibrous tissues, or vasculature. They can also arise from the bone marrow. tx: combination of surgical excision (sometimes requiring amputation) and adjunctive chemotherapy and/or radiation. Osteosarcoma-affects adolescents and young adults, malignant bone forming tumor, causes moth-eaten appearance to long bones such as femur chondrosarcoma-middle age and older adults; tumor infultrates trabeculae in spongy bone Fibrosarcoma-solitary tumor produces collagen and forms in metaphysial region of femur or tibia Giant cell tumor-females more than males, solitary tumor, causes bone resorption in femur, tibia, radius, humerus Myeloma-neoplastic proliferation of plasma cells causes bone lysis and infiltration of bone marrow

Describe the difference between dislocations and subluxations.

Dislocation (displacement of a bone from its normal articulation with a joint) or Subluxation (a partial abnormal separation of the articular surfaces of a joint)

Discuss the etiology, development, and clinical treatment of osteomyelitis.

Etiology-bacteria, viruses, fungi, and parasites. Exogenous osteomyelitis occurs when an infection has entered from outside the body and infected the bone (e.g., a puncture wound, animal bite, and intravenous drug abuse). Endogenous (hematogenous) osteomyelitis occurs when pathogens have been carried through the vascular system to the bone to cause the infection (e.g., sickle cell disease and human immunodeficiency virus [HIV] infection). Development-Microorganisms invade the bone and form small abscesses. This invasion causes an intense inflammatory response that weakens the bone and may predispose it to fracture. The organism may also be more virulent, invasive, and prolific in the immunocompromised or immunosuppressed patient (e.g., patients with HIV infection). Tx- Antibiotics combined with surgical débridement; significant excision and even amputation; Hyperbaric oxygen therapy

What is the most lethal bone tumor in children?

Ewing sarcoma

Describe disorders of skeletal muscle and a variety of secondary muscular dysfunctions and their clinical treatments.

Fibromyalgia-chronic musculoskeletal syndrome that can occur in a very mild state or be a very disabling disorder; tx-mind-body interventions, such as biofeedback, movement therapies, and relaxation techniques, as well as medication. Muscle membrane abnormalities -Myotonia is a delay in muscle relaxation following voluntary contraction; muscle cells remain depolarized in the absence of continued stimulation as a result of membrane dysfunction; tx:drugs that reduce muscle membrane excitability. -Periodic paralysis-abnormal muscle membrane ion channels. These abnormalities cause the muscle membrane to be unresponsive to neural stimulation. tx: underlying factors such as hyperthyroidism Metabolic muscle disorders-endocrine abnormalities or energy metabolism disorders Idiopathic inflammatory myopathies (IIMs)-dermatomyositis (DM), polymyositis (PM), necrotizing myopathy (NM), and sporadic inclusion body myositis (IBM). Tx: immunosuppressive therapy

Fracture healing process

Fracture hematoma: When bone is broken, damage to the local vasculature causes hematoma development and triggers initiation of the repair process. Callus formation: Dead bone tissue is either reabsorbed (osteoclastic process) or becomes the foundation for deposition of new bone tissue (callus). While the hematoma is reabsorbed into the body, callus tissue develops. This tissue binds the broken ends of the fractured bone together, thus stabilizing the fracture so that bone healing can take place. Bone remodeling: As healing progresses, callus tissue is eventually replaced by normal bone tissue until healing is complete.

Briefly describe the process of remodeling.

In phase 1 (activation), a stimulus (e.g., hormone, drug, vitamin, physical stressor) activates the cytokine system, particularly the tumor necrosis factor (TNF) superfamily, to form osteoclasts. Osteoclasts attach to the bone matrix by actin microfilaments and multiple other proteins that form foot-like structures called podosomes. Once attached, the osteoclasts' integrin receptors anchor its microfilaments to the extracellular matrix providing receptor pathways between the osteocyte and bone matrix. Lysosomal enzymes produced by osteoclasts "digest" bone; the osteoclasts then release the degraded bone products into the vascular system. After bone is resorbed, the osteoclast leaves behind an elongated cavity or resorption cavity. The resorption cavity in compact bone follows the longitudinal axis of the haversian system, whereas the resorption cavity in spongy bone parallels the surface of the trabeculae. New bone formation begins as osteoblasts lining the walls of the resorption cavity express osteoid and alkaline phosphatase, forming sites for calcium and phosphorus deposition. As the osteoid mineralizes, new bone is formed. Successive layers (lamellae) in compact bone are laid down, until the resorption cavity is reduced to a narrow haversian canal around a blood vessel. Old haversian systems are destroyed and new haversian systems are formed. New trabeculae are formed in spongy bone. The entire process of remodeling takes about 3 to 6 months.

How does a keloid differ from a normal scar?

Keloids are rounded, firm elevated scars with irregular clawlike margins that extend beyond the original site of injury. caused by abnormal wound healing with excessive fibroblast activity and collagen formation, and loss of control of normal tissue repair and regeneration; uncontrolled overgrowth causes extension beyond the site of the original wound, and the overgrowth becomes smoother, irregularly shaped, hyperpigmented, harder, and more symptomatic. The fibrous tissue that accumulates in keloids is associated with increased cellularity and metabolic activity of fibroblasts

which cells are involved in initiating immune responses in the skin

Langerhans cells

List two diseases caused by insect bites.

Lyme pruritis and urticaria

Which dystrophy is really a systemic disease?

Myotonic muscular dystrophy (MMD)

Compare the three forms of pemphigus.

Pemphigus vulgaris - most common. Oral lesions precede the onset of skin blistering, more prominent on the face, scalp, and axilla. The blisters rupture easily because of the thin, fragile overlying portion of the epidermis. Pemphigus foliaceus - milder form of the disease and involves acantholysis at the more superficial, subcorneal level of the epidermis with blistering, erosions, scaling, crusting, and erythema usually of the face and chest. Oral mucous membranes are rarely involved. Paraneoplastic pemphigus - most severe form and is associated with lymphoproliferative neoplasms. IgA pemphigus - most benign form characterized by tissue-bound and circulating IgA antibodies targeting desmosomal or nondesmosomal cell surface components in the basement membrane of the epidermis. Pemphigus herpetiformis - very rare form that resembles dermatitis herpetiformis (blistering lesions that have the appearance of herpes lesions) but with immunologic and histologic findings consistent with pemphigus.

Give three examples of papulosquamous disorders.

Psoriasis, pityriasis rosea, lichen planus, acne vulgaris, acne rosacea, and lupus erythematosus

Describe two types of muscle tumors and their treatment

Rhabdomyomas - rare and easily treated by excision. The most common locations for rhabdomyomas are the tongue, neck, larynx, uvula, nasal cavity, axilla, vulva, and heart. Rhabdomyosarcomas- highly malignant tumors that usually occur in infants, children, and teenagers. typically located in the head, neck, and genitourinary tract muscles but may also occur in the trunk and extremities. one of three types: Anaplastic/pleomorphic-highly malignant, spindle cell Embryonal- tadpole or tennis racquet shaped Alveolar-lattice like Tx: excision, radiation, and chemotherapy.

How does rheumatoid arthritis affect the skin, heart, lungs, and kidneys?

Rheumatoid nodules within the heart may cause valvular deformities, particularly of the aortic valve leaflets, and pericarditis. Involvement of blood vessels results in an acute necrotizing vasculitis, characteristic of that noted in other immunologic/inflammatory states. Thromboses of such involved vessels may lead to myocardial infarctions, cerebrovascular occlusions, mesenteric infarction, kidney damage, and vascular insufficiency in the hands and fingers (Raynaud phenomenon)

Describe rubella and rubeola.

Rubella is a common communicable disease of children and young adults caused by a ribonucleic acid (RNA) virus that enters the bloodstream through the respiratory route. incubation period ranges from 14 to 21 days. Prodromal symptoms include enlarged cervical and postauricular lymph nodes, low-grade fever, headache, sore throat, rhinorrhea, and cough. A faint-pink to red coalescing maculopapular rash develops on the face with spread to the trunk and extremities 1 to 4 days after the onset of initial symptoms rash is thought to be the result of virus dissemination to the skin. The rash subsides after 2 to 3 days, usually without complication, usually not contagious after development of the rash Rubeola is a highly contagious, acute viral disease; Transmitted by direct contact with droplets from infected persons, rubeola is caused by an RNA-containing paramyxovirus with an incubation period of 7 to 12 days, during which there are no symptoms;virus enters the respiratory tract and attaches to dendritic cells and alveolar macrophages, amplifies in local lymphatic tissue, and progresses to systemic disease; high fever (up to 40.5° C [104.9° F]), malaise, enlarged lymph nodes, rhinorrhea, conjunctivitis, and barking cough. Within 3 to 4 days, an erythematous maculopapular rash develops over the head and spreads distally over the trunk, extremities, hands, and feet. Early lesions blanch with pressure, followed by a brownish hue that does not blanch as the rash fades. Characteristic pinpoint white spots surrounded by an erythematous ring develop over the buccal mucosa and are known as Koplik spots. These spots precede the rash by 1 to 2 days. The rash then subsides within 3 to 5 days.

What stimulates pruritus?

Small unmyelinated type C nerve fibers transmit itch sensations and specific spinal pathways may carry itch sensations to the brain itch mediators, including histamine, serotonin, prostaglandins, bradykinins, neuropeptides, acetylcholine, and interleukins-2 and -31

How is Kaposi sarcoma related to AIDS?

The rapidly progressive form associated with AIDS tends to spread symmetrically over the upper body, particularly the face and oral mucosa. About 75% of individuals with epidemic KS have involvement of lymph nodes, particularly in the gastrointestinal tract and lungs. Individuals receiving highly active antiretroviral therapy (HAART) have a markedly reduced incidence of KS.

What dangers accompany frostbite?

There is numbness and no sensation of pain. Frostbite injury is related to direct cold injury to cells, indirect injury from ice crystal formation, and endothelial cell damage. During rewarming, there is progressive microvascular thrombosis followed by reperfusion injury. Edema can cause capillary compression and vascular stasis. Third-degree and fourth-degree frostbite result in gangrene with loss of tissue

fracture classification system purpose

To simply provide a brief description of the injury To provide a more detailed description to better predict the treatment that will be necessary To determine the impact of the fracture on the growth of a child To determine the prognosis of the healing process of the bone

different types and treatments of fractures.

Traction or external fixation device Cast, splint, or immobilizer Closed reduction (realignment) Surgical open reduction

How do blood vessels penetrate into the inner structures of the bone?

Volkmann canals

What is the primary pathology of epicondylopathy?

When force is sufficient to cause microscopic tears (microtears) in tissue Lateral epicondylopathy (tennis elbow) is caused by irritation and overstretching of the extensor carpi radialis brevis (ECRB) tendon and forearm extensor muscles, resulting in tissue degradation, loss of grip strength, and pain.14 Medial epicondylopathy (golfer's elbow) is the result of similar forces affecting the forearm muscles responsible for forearm flexion and pronation

Why is myoglobinuria a dangerous complication of rhabdomyolysis?

acute renal failure (myoglobin precipitates in the tubules, obstructing flow through the nephron and producing injury)

Name one toxic myopathy, and explain why it develops.

alcohol necrosis of individual muscle fibers; whole segments can be found in the same stage of degeneration. The mechanism by which alcohol affects the muscle fiber is uncertain, 1027but a direct toxic effect and nutritional deficiency have both received experimental support.

Why does inflammation occur with contact dermatitis?

allergen contacts the skin, the allergen is bound to a carrier protein, forming a sensitizing antigen. The Langerhans cells (antigen presenting dendritic cells) process the antigen and present it to T cells. T cells then become sensitized to the antigen, inducing the release of inflammatory cytokines and the symptoms of dermatitis. In latex allergy, there is either a type IV hypersensitivity reaction to chemicals used in latex rubber processing or a type I immediate hypersensitivity reaction with immunoglobulin E (IgE) antibodies formed in response to latex rubber protein. In delayed hypersensitivity (type IV), several hours pass before an immunologic response is apparent. The T cells play an important role because they differentiate and secrete lymphokines that affect macrophage (Langerhans cells) movement and aggregation, coagulation, and other inflammatory responses. Sensitization usually develops with first exposure to the antigen, and symptoms of dermatitis occur with reexposure. Irritant contact dermatitis is a nonspecific inflammatory dermatitis caused by activation of the innate immune system by proinflammatory properties of chemicals.

Dermal appendages include which of the following structures

apocrine glands nails hair eccrine glands

Give two examples of insect bites or parasites that affect children. What features are observed in each?

bedbugs - red macule that develops into a nodule, lasting up to 14 days. fleas - clusters along the arms and legs or where clothing is tight fitting, such as near elastic bands that circle the thigh or waist. The bite produces a urticarial wheal with a central hemorrhagic puncture pediculosis - inpoint red macule, papule, or wheal with a hemorrhagic puncture site; nits in head lice scabies - primary lesions are burrows, papules, and vesicular lesions, with severe pruritus that worsens at night

From what cells do bone tumors originate?

bone cells, cartilage cells, fibrous tissue cells, or vascular marrow cells

What features distinguish urticarial lesions?

circumscribed area of raised erythema and edema of the superficial dermis; The leakage of fluid from the vessel appears as wheals, welts, or hives, and there may be few or many that may be distributed over the entire body.

which component of the bone matrix gives bone its tensile strength

collagen

How are fractures classified?

complete-bone is broken entirely incomplete-bone is damaged but is still in one piece (greenstick, torus, bowing) open - compound, skin open closed-simple, skin not open, incomplete comminuted fracture -bone breaks into more than two fragments linear fracture - runs parallel to the long axis of the bone. oblique fracture - occurs at a slanted angle to the shaft of the bone. spiral fracture - encircles the bone transverse fracture - occurs straight across the bone. pathologic-insufficiency or fragility- break at the site of a preexisting abnormality, resulting from force that would not fracture a normal bone stress- During activities that subject a bone to repeated strain, such as certain athletics, fracture can occur in normal or abnormal bone fatigue - caused by repetitive, sometimes abnormal stress or torque applied to a bone with normal ability to deform and recover. transchondral fracture - consists of fragmentation and separation of a portion of the articular cartilage.

What are some causes of compartment syndrome?

conditions that increase the contents of the compartment (such as bleeding after a fracture), decrease the compartment volume (such as a tight bandage or cast), or a combination of both conditions that result in disturbing the muscle's microvasculature, Any condition that disrupts the vascular supply to an extremity (such as severe burns, bleeding disorders, crush injury, snake or insect bites, extremely tight bandages, or casts) can cause increased pressure within the muscle compartments.

when describing a freely moveable joint, which term should be used

diarthrosis

What is the main objective clinical finding in fibromyalgia?

diffuse, chronic pain

What lesions are typical of atopic dermatitis in children?

eczematoid appearance with redness, edema, and scaling

How do metabolic muscle diseases develop? What causes them?

endocrine abnormalities or diseases of energy metabolism, such as glycogen storage disease, enzyme deficiencies, and abnormalities in lipid metabolism and mitochondrial function

Name three differences between slow-twitch and fast-twitch muscle fibers.

fast-twitch - rely on a short-term anaerobic glycolytic system for rapid energy transfer. White muscle. innervated by large type II alpha motor neurons slow-twitch fibers - depends on aerobic oxidative metabolism. Red muscle. innervated by relatively small motor neurons

Name two bacterial skin infections, and describe the typical lesions.

folliculitis- pustules with a surrounding area of erythema. Faruncle (boil) - deep, firm, red, painful nodule 1 to 5 cm in diameter. Within a few days, the erythematous nodules change to a large, fluctuant, and tender cystic nodule accompanied by cellulitis. may drain large amounts of pus and necrotic tissue. carbuncles - firm mass that evolves into an erythematous, painful, swollen mass that drains through many openings. Abscesses may develop.

Bone function

give form to the body, support tissues, and permit movement, protect many of the body's vital organs, mineral homeostasis (storing minerals [i.e., calcium, phosphate, carbonate, magnesium], play a role in hormone homeostasis, and assist in maintaining normal immunologic function.

What factors are associated with atopic dermatitis?

history of hay fever or asthma and is associated with IgE antibodies

Fat cells are located in the

hypodermis (subcutaneous layer)

Compare the cause and presentation of impetigo and staphylococcal scalded-skin syndrome.

impetigo -Staphylococcus aureus (S. aureus) and, less commonly, Streptococcus pyogenes cause impetigo. nonbullous and, more rarely, bullous (caused only by S. aureus), where blisters enlarge or coalesce to form bullae; Both forms of impetigo begin as vesicles with a thin vesicular roof composed of stratum corneum that ruptures to form a honey-colored crust; located on the face, around the nose and mouth, but the hands and other exposed areas also are involved. crusted erosions or ulcers staph scalded skin syndrome -caused by virulent group II strains of staphylococci that produce an exfoliative toxin. fever, malaise, rhinorrhea, and irritability followed by generalized erythema with exquisite tenderness of the skin. There may be an associated impetigo, but the infection often begins in the throat or chest. The erythema spreads from the face and trunk to cover the entire body except for the palms, soles, and mucous membranes. Within 48 hours, blisters and bullae may form, giving the child the appearance of being scalded. Perioral and nasolabial crusting and fissures develop

Compare a strawberry hemangioma with a cavernous hemangioma.

infantile hemangiomas are apparent at birth, but usually emerge 3 to 5 weeks after birth. They grow rapidly during the first few years of life and become bright red and elevated with minute capillary projections that give them a strawberry appearance. Only one lesion is usually present and is located on the head and neck area or trunk. After the initial growth, the lesion grows at the same rate as the child and then starts to involute at 12 to 16 months of age. Cavernous hemangiomas are a rare variant of superficial hemangiomas and are GLUT1-negative. They are present and fully grown at birth and are usually solitary lesions on the head or limbs that appear as a spongy purplish mass of tissue. They have larger and more mature vessels within the lesion. There are two groups of cavernous hemangiomas: rapidly involuting and noninvoluting. Rapidly involuting cavernous hemangiomas disappear by 12 months to 14 months of age, leaving an area of thin skin. Noninvoluting cavernous hemangiomas do not undergo involution.

How does noninflammatory joint disease differ from inflammatory joint disease? Describe two principal features of each.

inflammatory-inflammatory damage or destruction in the synovial membrane or articular cartilage and by systemic signs of inflammation (fever, leukocytosis, malaise, anorexia, hyperfibrinogenemia).

Compare keratoacanthoma and actinic keratosis.

keratoacanthoma is a benign, self-limiting tumor of squamous cell differentiation arising from hair follicles on sun damaged skin Actinic keratosis is a premalignant lesion composed of aberrant proliferations of epidermal keratinocytes caused by prolonged exposure to ultraviolet radiation.

How does the presence of metastatic tumors affect treatment options and prognosis of persons with osteosarcoma

long term survival rate not good surgery depends on metastasis; attempts for limb salvage; if unable, chest radiographs monitored for mets

Identify the pathophysiology of metabolic and inflammatory muscle diseases.

metabolic muscle diseases: Endocrine-based Thyrotoxicosis Disorders of energy metabolism Glycogen storage diseases Acid maltase deficiency Myoadenylate deaminase deficiency Lipid deficiencies Inflammatory: Myositis is a general term that describes inflammation of the muscles. In some cases it can be the result of infection. Infectious myositis can be caused by a number of organisms. Polymyositis is an autoimmune disorder; Inclusion body myositis (IBM) is the most common acquired muscle disease. Muscle damage caused by drugs or toxins is also called toxic myopathy. Alcohol, lipid-lowering agents (fibrates and statins), antimalarial drugs, steroids, thiol derivatives, and narcotics (particularly heroin) can all cause symptoms. Many drugs, diseases, and infectious and environmental agents can cause myopathy.

How do monosodium urate crystals cause gout to develop?

monosodium urate crystals form and are deposited in joints and their surrounding tissues, initiating a powerful inflammatory response; urate excretion 1019by the kidneys is sluggish. The sluggish excretion may be the result of a decrease in glomerular filtration of urate or acceleration in urate reabsorption. In addition, monosodium urate (MSU) crystals are deposited in renal interstitial tissues, causing impaired urine flow. 1. Monosodium urate precipitates at the periphery of the body, where lower body temperatures may reduce the solubility of monosodium urate. 2. Albumin or glycosaminoglycan levels decrease, which causes decreased urate solubility. 3. Changes in ion concentration and decreases of pH enhance urate deposition. 4. Trauma promotes urate crystal precipitation.

Describe the incidence and types of child maltreatment or abuse.

more than 2.0 million children are abused per year in the United States. Maltreatment may be psychologic, sexual, or physical

Discuss the clinical manifestations of Duchenne muscular dystrophy.

muscle weakness, difficulty walking, and large calves (pseudohypertrophy) caused by normal muscle fiber replacement with fat and connective tissue; weakness starts in the pelvic girdle, initially causing difficulty rising from the floor (Gower sign) and climbing stairs, and a waddling gait because of weakness in the lumbar and gluteal muscles; toe-walk because of weakness of the anterior tibial and peroneal muscles, causing the feet to assume a talipes equinovarus position; loss of ability to ambulate by 8 to 13 years of age; contractures of the knees, hips, and other joints, and scoliosis; osteoporosis and pathologic fractures, breathing difficulty, constipation and urinary urgency, Mild to moderate cognitive

What is the cause of Duchenne muscular dystrophy?

mutation in a specific gene that leads to alterations in the muscle protein dystrophin

What are the risk factors for osteomyelitis?

open fractures, penetrating wounds, or surgical procedures, metabolic and vascular diseases (diabetes, peripheral vascular disease), lifestyle risks (smoking, alcohol or drug abuse), and advanced age chronically ill, have diabetes or alcoholism, or are receiving large doses of steroids or immunosuppressive drugs

Review the most common joint diseases, their pathophysiology, and their treatment.

osteoarthritis patho- Loss of articular cartilage resulting from mechanical stress and the activation of enzymes that break down proteoglycans, glycosaminoglycans, and collagen. Subchondral bone sclerosis, cysts, and microfractures as the destruction of this cushioning structure continues. Overgrowth of bone around the area of articular damage, which can result in protrusions called osteophytes that can impinge on other structures and limit mobility TX-rest, physical therapy, weight loss, and analgesics (first line NSAIDs). Intra-articular injection of corticosteroids and high-molecular-weight viscose supplements as well as injections of platelet-rich plasma (PRP), Surgical repair or joint replacement RA patho-idiopathic autoimmune disorder that is characterized by the formation of autoantibodies to synovial tissue. Neutrophils and macrophages are activated within the synovial membrane and release numerous inflammatory cytokines, especially tumor necrosis factor-alpha (TNF-α) and interleukin-1 (IL-1). he immune and inflammatory processes result in degradation of joint tissues and formation of a mass of intra-articular degradation tissue known as a pannus. TX-disease-modifying antirheumatic drugs (DMARDs), such as methotrexate (MTX). ankylosing spondylitis (AS) patho-systemic, autoimmune, inflammatory joint disorder. AS primarily targets the joints of the spine and sacroiliac joint; inflammation at Enthesis (point at which tendons, ligaments, and joint capsule insert into bone) TX-Pharmacologic and surgical gout patho-related to the excessive production of uric acid caused by a dysfunction of purine metabolism and elimination. An increase in serum urate concentration (hyperuricemia) Recurrent attacks of monoarticular arthritis (inflammation of a single joint) Deposits of monosodium urate monohydrate (tophi) in and around the joints Renal disease involving glomerular, tubular, and interstitial tissues and blood vessels The formation of renal stones. TX-Colchicine and NSAIDs (indomethacin), prednisone, low-purine diet

Name the different types of bone cells.

osteoblasts, osteocytes, and osteoclasts

What are the most common benign bone tumors of children?

osteochondroma and nonossifying fibroma

What are the major cells involved in bone resorption?

osteoclasts

once their initial function is complete, what do osteoblasts become

osteocytes

Describe the etiology, pathophysiology, and clinical manifestations of osteoporosis, osteomalacia, and Paget disease.

osteoporosis etiology- Genetics, Thin build, Hormonal deficiencies, Medications such as glucocorticoids, selective serotonin reuptake inhibitors (SSRIs) and anticoagulants, Inadequate dietary intake of calcium and vitamin D, Sedentary lifestyle, Smoking, disease states (renal failure, rheumatoid arthritis, and spinal cord injury) and many medications (corticosteroids, hormonal blockers, and chemotherapeutic agents) patho- increase in bone resorption and a decrease in bone formation, which results from an imbalance in osteoclast and osteoblast activity; This imbalance diminishes bone density and bone quality, especially in trabecular bones (vertebrae, wrist, femoral neck, and ribs). In menopausal osteoporosis, estrogen deficiency is associated with accelerated bone resorption and rapid bone loss that begins during the perimenopausal and early menopausal periods. Decreased bone formation is more problematic in the late periods of menopause. sx- fractures, especially of vertebrae (compression fracture), femoral neck, wrist, and ribs osteomalacia (rickets in children) etiology-deficiency of vitamin D, which is necessary to regulate calcium ion absorption from the intestines. patho-In the absence of vitamin D, serum calcium levels decrease, stimulating secretion of parathyroid hormone (PTH); PTH raises serum calcium levels, it decreases serum phosphate levels; PTH raises serum calcium levels, it decreases serum phosphate levels; sx-skeletal pain and tenderness (often felt in the hips, making walking difficult), muscular weakness, and increased risk of fractures. Paget etiology- not yet fully known, but studies have implicated both genetic and environmental factors patho-increased metabolic activity resulting in excessive bone remodeling. The process begins with excessive resorption of spongy bone and the replacement of bone marrow by vascular fibrous tissue. Formation of this abnormal new bone occurs at an accelerated rate, causing the thickening and enlarging of the bone. sx-Asymmetry of the skull, neurologic abnormalities, Thickening of the maxilla and mandible, displacement of teeth and malocclusion, excessive lateral curvature of the femur and anterior curvature of the tibia

What are the two malignant bone tumors found in children?

osteosarcoma and Ewing sarcoma.

What areas are at greatest risk of pressure ulcers?

over bony prominences, such as the sacrum, heels, ischia, and greater trochanters.

What lesions are associated with papulosquamous disorders?

papules, scales, plaques, and erythema

What is the pathophysiology of osteochondrosis?

partial loss of blood supply, death of bone (osseous necrosis), progressive bony weakness, and then microfracture.

How are chickenpox and herpes zoster related?

produced by the varicella-zoster virus (VZV) Varicella occurs in people not previously exposed to VZV, whereas herpes zoster (shingles) occurs in individuals who had varicella in the past. The virus enters the dorsal root ganglia and remains latent.

What causes diaper dermatitis?

prolonged exposure to and irritation by urine and feces as well as maceration by wet diapers or airtight plastic diaper covers, secondarily infected with Candida albicans

How does osteoporosis differ from osteomalacia? Name three differences

pseudofractures, along with radiolucent bands perpendicular to the surface of involved bones can help differentiate osteomalacia from fragility fractures that are seen in osteoporosis

How has MRSA changed musculoskeletal infections in children?

serious increases in morbidity and mortality have developed

A nurse recalls fibrous joints usually are

slightly moveable

How do the following joints differ from each other: synarthrosis, amphiarthrosis, and diarthrosis?

synarthrosis (immovable joint), an amphiarthrosis (slightly movable joint), or a diarthrosis (freely movable joint).

Name at least two characteristics of each of the joints in the previous question that either facilitate or hinder movement.

synarthrosis - fibrous suture tight union (children's skulls); fibrous gomphosis conical projection fits into a complementary socket and is held in place by a ligament (teeth held in mandible and maxilla) amphiarthrosis - fibrous syndesmotic joint united by ligament or membrane (radius, ulna, tibia, fibula); cartilaginous synchondrosis hyaline cartilage connectsbones (between ribs and sternum); cartilaginous symphysis bones are united by a pad or disk of fibrocartilage acting as shock absorber (pubic symphysis and intervertebral disks) diarthrosis - synovial uniaxial, biaxial, or multiaxial, circular or angular movement

For a patient with candidiasis which factor will exacerbate the condition

systemic antibiotics

Define the differences between tendons and ligaments.

tendons attach muscle to bone ligaments attach bone to bone fibroblasts in tendon are arranged in parallel rows; fibroblasts appear less organized in ligaments. In the proteoglycan matrix of tendons, collagen oligomeric matrix protein (COMP) assists in providing gliding and viscoelastic properties. Ligament fibers typically contain a greater proportion of elastin. Tendons fx (1) transferring forces from muscle to bone and (2) acting as a type of biologic spring for muscles to allow additional stability during movement. Ligaments stabilize joints by restricting movement.

when assessing a patient diagnosed with localized scleroderma, which changes in the skin will be observed

thickening

What are some changes that occur in skin with aging?

thinner, dryer, and more wrinkled; DNA repair decreases; Epidermal cells less moisture and change shape; dermis thins, easily tears; permeable and irritated; smooth, shiny, and wrinkled; loss of elastin; loss of flexibility/collagen fibers; barrier function reduced; decreased decreased Langerhans cells; dermoepidermal border flattens, shortening and decreasing the number of capillary loops; Wound healing decreases ; fewer melanocytes; Atrophy of eccrine, apocrine, and sebaceous glands; reduced sensory perception; increased risk of heat stroke and hypothermia; nails brittle

Why is an early diagnosis of developmental dysplasia of the hip imperative?

to ensure good outcome

Why is adenosine triphosphate (ATP) used for muscle contraction?

to fuel the complex processes of muscle contraction, driving the cross-bridges of actin and myosin together

Name three functions of articular cartilage.

to reduce friction in the joint and to distribute the forces of weightbearing. 1. Allows smooth movement of opposing joint surfaces 2. Distributes joint contact forces 3. serves as a wear resistant, smooth and nearly frictionless load bearing surface

What is the most common orthopedic injury in NAT?

transverse tibia fracture

Compare herpes zoster and varicella.

varicella-zoster virus (VZV). VZV occurs as a primary infection followed years later by activation of the virus to cause herpes zoster (shingles). During this time, the virus remains latent in trigeminal and dorsal root ganglia. Herpes zoster has initial symptoms of pain and paresthesia localized to the affected dermatome (the cutaneous area innervated by a single spinal nerve), followed by vesicular eruptions that follow a facial, cervical, or thoracic lumbar dermatome