13.3 Musculoskeletal and Integumentary Effects

TCO IV.A.6 and IV.A.7 test musculoskeletal and integumentary acute, chronic, and late effects. Bones, joints, muscle, growth plates, skin, nails, wounds, and central-line dressing sites are the organs. This is not the surgical-staging chapter and not the full GVHD grading lecture. Here the nurse keeps a steroid-weak child from falling, names avascular necrosis (AVN) instead of "growing pains," and does not call every purple spot a bruise when ecthyma gangrenosum is on the differential.

A 6-year-old on dexamethasone who cannot rise from the toilet, a 15-year-old after osteosarcoma limb salvage who will not bear weight, and a neutropenic toddler with a black necrotic skin lesion are the pictures.

Muscle, bone, joints, and growth

Steroid myopathy is proximal weakness from dexamethasone or prednisone. Dexamethasone is often harsher. The child cannot climb stairs, rise from the floor, or get off the toilet without using the arms (a pediatric Gower-like pattern). Mood lability travels with the same drug. Involve physical therapy, pad falls, do not force competitive physical education, and do not stop corticosteroids abruptly—adrenal insufficiency is an endocrine trap. Weakness that is distal, asymmetric, or accompanied by foot drop is more vincristine neuropathy than steroid myopathy; both cause falls.

AVN (osteonecrosis) of the hips and knees is a steroid late effect, especially in adolescents on acute lymphoblastic leukemia pathways. Pain with weight bearing, a limp, and limited internal rotation are not "attention-seeking after clinic." Imaging as ordered (often magnetic resonance imaging) belongs early. Activity modification, pain control, and orthopedic referral follow. Do not tell a 16-year-old that AVN will "grow out" because steroids have stopped.

Methotrexate osteopathy is bone pain, osteopenia, and sometimes fractures during long-term or high-dose methotrexate exposure. It is not automatically AVN and not automatically vincristine pain. Report new bony point tenderness.

After amputation or limb-salvage reconstruction for osteosarcoma or Ewing sarcoma, rehabilitation is the treatment: residual-limb shaping, phantom-limb pain recognition, prosthesis or endoprosthesis precautions, and school re-entry that includes hall passes and no contact sport until orthopedics clears. A child who will not look at the limb is not "noncompliant"; involve child life and physical and occupational therapy. Vincristine neuropathy on the remaining limb plus a new prosthesis is a fall disaster—teach night lights, non-skid socks, and an ankle-foot orthosis when foot drop appears.

Radiation across a growth plate (physis) can arrest that plate and produce limb-length discrepancy, scoliosis, or hypoplasia of the irradiated field years later. Young age raises risk. Survivorship measurement of leg lengths and a shoe lift are nursing and orthopedic business, not a surprise at a 10-year reunion. Do not invent a single gray threshold as ONCC fact; teach field, age, and surveillance.

Skin, nails, wounds, and line sites

Radiation dermatitis ranges from erythema and dry desquamation to moist desquamation in the beam. Keep skin clean, use protocol moisturizers, avoid extra adhesive, alcohol, and heating pads in the field, and protect from sun. Do not scrape peel; moist areas need a wound plan, not powder from home.

Acute GVHD rash after allogeneic HSCT is often maculopapular and likes palms, soles, and ears. Chronic GVHD can be lichenoid or sclerodermatous. Photograph, grade as the transplant team directs, and do not start a new lotion that masks the exam. Chemotherapy rashes vary; epidermal growth factor receptor (EGFR) inhibitor papulopustular rash is an adult pattern that is rare in pediatrics—mention it so you do not import adult drug lists as CPHON default.

Hand-foot syndrome (palmar-plantar erythrodysesthesia) from selected agents (high-dose cytarabine in some children; other protocol drugs) is painful erythema, swelling, and blistering of palms and soles. Pain control, cooling, and holding or reducing the drug as ordered beat another alcohol-based sanitizer marathon. Steroid acne is facial and truncal pustules on dexamethasone or prednisone; it is not necessarily infection, but superinfection happens—do not pick.

Petechiae from thrombocytopenia are pinpoint, non-blanching, often pressure-site or dependent. They are not ecthyma gangrenosum, which is a necrotic, often black lesion in a neutropenic child and is Pseudomonas (or other gram-negative) until proven otherwise—an infectious emergency, not a "watch the bruise" note. Fever plus a new necrotic skin lesion is a same-hour workup.

Photosensitivity follows selected agents (including some methotrexate and other protocol drugs) and radiation: teach sun protection, hats, and that "a little sun for vitamin D" is not the plan during photosensitizing therapy. Nail changes—lines, pigmentation, onycholysis, or paronychia—follow many cytotoxics; keep nails short and report painful nail-fold infection in neutropenia.

Wound healing fails when the child is neutropenic or malnourished. Surgical incisions, biopsy sites, graft harvest sites (autologous skin or bone grafts, HSCT harvest sites), and central-line dressing skin all need a sterile, adhesive-minimizing plan. Do not change a stable central-line dressing daily "just because," and do not ignore a red tunnel. Pressure injury in immobile children—steroid myopathy, vincristine neuropathy, postoperative bone-sarcoma, or mucositis pain that keeps a child in one position—is preventable with turning, surfaces, and nutrition. A stageable pressure injury on a 7-year-old is a nursing quality event, not "kids don't get bedsores."

The CPHON product is a child who is not falling on dexamethasone, whose hip pain is imaged rather than dismissed, whose necrotic skin lesion is treated as infection, and whose radiation field and line dressing are protected rather than decorated with home adhesive.