Mobility wk 11 Flashcards
Parathyroid hormone and Ca++ feedback loop
Low serum Ca++
Parathyroid gland releases PTH»_space;
- Ca++ release from bone, incr
- Ca++ reabsorption from kidneys
- incr Ca++ absorption in sm intestine (with help of Vit D & calcitriol)
Incr serum Ca++
PTH release suppressed
Calcitonin and Ca++ feedback loop
High serum Ca++
Thyroid gland releases calcitonin»_space;
- addition of Ca++ to bone
- decr absorption of Ca++ in sm intestine
Low serum Ca++
Calcitonin release suppressed
Lack of dietary Ca++
leads to bone breakdown to incr serum Ca++
Needed for muscle fx
RANKL
Hormone that increases bone loss
Osteoporosis drugs target this to decr bone loss
Should be in balance w/ OPG
OPG
Hormone that decrease bone loss
Should be in balance w/ RANKL
Osteoporosis risk and gender
Women @ incr risk (esp. menopausal)»_space; decr estrogen = incr renal excretion of Ca++
Women more likely to frac hip that get breast/ovarian cx
Men start out w/ higher bone density d/t androgens and testoterone
General osteoporosis risk factors
Female, low estrogen, Depo-Provera Small boned, thin Hyperthyroid (Ca++ control in thyroids) Smoking, etoh Low impact exercise lifestyle On chronic corticosteroids (pts w/ RA, lung dx on prednisone & at risk) Kidney, liver dx
Pts at risk for osteoporosis
Vit C, D deficiencies Malabsorption (ulcerative colitis) Hist. of excessive caffeine, etoh, nicotine Non-wt bearing Thyroid disorders Kidney dx Estrogen deficiency
Posture suggesting bone dx
Scoliosis
Kyphosis
Lordosis
Compression fractures
Pts w/ osteoporosis at risk for
Doesn’t take much force
New onset of back pain w/o traumatic even may indicate
Vitamin D
D2 is from dietary sources
D3 is from sunlight
- incr absorption of Ca++ from GI tract
- decr renal excretion of Ca++
- activation is determined by Ca++ avail
Blood serum levels: 18-80 ng/mL
- low levels seen in osteoporosis, malabsorption prob, CKD, liver dx
Proteoglycans
Needed for production of synovial fluid
Why are weight bearing activities important
Triggers the body to deposit more Ca++ in bone
Drugs from bone disorders
Ca++ supplement Vit D Bisphosphonates (fosamax) Selective estrogen receptor modulators Calcitonin HRT PTH analog
alendronate (Fosamax)
Bisphosphonate, bone metabolism regulator
MOA: Minimize loss of bone density, decr #/activity of osteoclast
Route & dose: PO, 5-10 mg 1x/d
Contra: GERD, esophageal prob
Caution: renal impairment
ADR: hypocalcemia, esophageal ulceration, N/V, atypical femoral fractures (sx: ext rotation of foot will cause pain)
Nrs: assess swallow (esoph. prob)
Edu: take w/ fluids, avoid lying down for 30 mins, report persistent joint pain
Take 30 min b4 food: Ca++ and food decr
absorption
denosumab (Prolia, Xgeval)
RANKL inhibitor
Osteoporosis
bone resorption outpaces bone deposition
Baclofen (Lioresal)
Centrally acting Muscle relaxer
Inhibit motor neuron in brain and spinal cord, decr pain, incr ROM
NO DIRECT EFFECT ON MUSCLES
Reduces spasticity assoc w/ spinal cord injury, (not stroke)
ADRs: CNS depressant - AVOID etoh, nausea, constipation
Sudden stopping > hallucinations, sz, paranoia
