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Low bone mass and microarchitectural deterioration of bone tissue. Leads to enhanced bone fragility and an increased fracture risk


Most common types of osteoporosis related fractures

1/2 vertebral, 1/4 are hip, 1/4 are wrist


Fracture rate increases after age...



After what age are women 3x more likely to have a fragility fx



Risk factors for osteoporosis

Caucasian, female, late menarche, nulliparity, early menopause, excessive exercise, age > 75, family hx, small body frame


Idiopathic secondary osteoporosis

Subset of women with no apparent etiology or secondary cause


Nutritional osteoporosis

Milk intolerance, vegetarianism, low calcium diet, excessive alcohol intake


Lifestyle osteoporosis

Caused by smoking, inactivity


Medical osteoporosis

Type 1 diabetes, cushings, chronic renal disease, IBD, cystic fibrosis, hyperparathyroidism, hyperthyroidism, anorexia nervosa, celiac disease, idiopathic hypercalciuria, premature ovarian failure


Medications causing osteoporosis

glucocorticoids, long term lithium therapy, chemotherapy, antivonculsants like phenytoin, phenobarbital, valproate, and carbamazepine... long term phosphate binding antacid, thyroid replacement drugs, methotrexate


Prevent bone loss in asymptomatic females

change nutrition, change lifestyle


decreased bone strength is related to many factors other than bone mineral density

effected by rates of bone formation, rates of bone resorption (turnover), bone geometry (size and shape), microachitecture


Age related loss of trabecular bone

breakdown of the trabecular network where it thins with separation of vertical structures or horizontal structures -- pictures c and d are defined as osteoporosis


bmd screening for postmenopausal women and men

no universally adapted approach for screening


premenopausal women bmd screening

not routinely recommended. healthy, premenopausal women with concerns about bone health may request one, but it is not recommended


international society of clinical densitometry guidelines allow screening for premenopausal women with 2 select circumstances

- history of fragility fracture, known secondary causes of osteoporosis, needing pharmacological therapy for osteoporosis, need to monitor drug therapy for osteoporosis, women in menopausal transition with a specific risk factor like low body weight, low trauma fx or high risk med


T Score

diagnostic threshold for low bone mass and osteoporosis based upon BMD measurements compared with a young adult reference population


The majority of postmenopausal women with osteoporosis have bone loss related

estrogen deficiency and/or age


WHO defines osteoporosis as bone mineral density score of

2.5 standard deviations less than the mean value for a young person of the same gender


vertebral fx are assoc with

loss of stature caused by a progressive increase in the degree of kyphosis and lordotic curve flattening -- causing shrinking leading to vertebral collapse


premenopausal considerations

bmd alone cannot define osteoporosis. like fragility fx, bmd is an indicator for further evaluation. fx and low bone mass are less common in premenopausal women.


low bone mass may be related to

either inadequate peak bone mass acquisition and or ongoing bone loss


postmenopausal considerations

no manifestations until fx, if no s/s they assume they do not have osteoporosis, vertebral fx is the most common fx, 2/3 of fxs are asymptomatics dx as incidental findings on xray, hip fx common in 15 percent of women and 5 percent of men by age 80


making the dx of osteoporosis

may be made with a fragility fx particularly spine, hip, wrist, humerus, rib, pelvis without a measurement of BMD


Fragility fx

occur from a fall from a standing height or less, without major trauma like a MVA


Bones not a/w fragility fx

skull, cervical spine, hands, feet, ankles


stress fx

associated with repetitive injury and are not fragility fx


BMD useful for

dx osteoporosis, predict fracture risk, monitor response to therapy. Low BMD a/w increased risk of fx, regardless of the technique of measurement


serology evaluation of osteoporosis

CMP, CBC, TSH. Normal ca, tsh and cr rule our hyperparathyroid, hyperthyroid and renal disease. normal blood count, serum protein and normal ca rule out multiple myeloma. for elderly, order 25-hydroxyvitamin D and PTH


radiography imaging osteoporosis

plain radiography are unremarkable until bone loss has reached 30%. signs of overall bone loss density (osteopenia) can be caused by moderate osteoporosis of the thoracic and lumbar spine. widening of the medullary canal with thinning of the cortices can be seen with long bones. fx may not be seen on initial radiographs, and may require bone scintigraphy, CT, MRI or repeat plain radiographs


BMD Zscores - age matched comparison will

identify individuals requiring futher evaluation for secondary causes of osteoporosis


clinical risk factors for fracture

advancing age, previous fx, glucocorticoid therapy, partental hx of hip fx, low body weight, current cigarette smoking, excessive alcohol consumption, RA, secondary osteoporosis


standard test to dx osteoporosis

dual-energy xray absorptiometry (DEXA)



measures bone density at the femoral neck, spine and distal radius. Results are related to T scores: the number of standard deviations the bone mineral density measurement is above or below the young normal mean BMD. Only method for dx osteoporosis in the absence of a fragility fx


Bone strength =

bone mineral density


Bone quality =

other properties of bone other than BMD/bone strength


Non-BMD determinents of bone strength

bone turnover, architecture (size, shape and bone geometry), microarchitecture (trabecular thickness, trabec connectivity, trab perforation, cortical thickness, cortical porosity), damage accumulation, matrix properties (crystal size and orientation)


T Score

classification of BMD by DXA according the SD difference between a patients BMD and that of a young adult reference population.


Osteoporosis T score

2.5 SD or more below the young adult mean BMD provided that other causes of low BMD are ruled out like osteomalacia



t score 1-2.5 SD below the young adult mean


Normal bone density

within 1 SD of the mean value in the young adult reference population


Osteoporosis screening uses these two tests

BMD and fracture risk assessment


severe established osteoporosis

more than 2.5 SD below the adult young female reference in the presence of one or more fragility fx


Z Score

comparison of the patients BMD to an age matched population. 2.0 or lower is below the expected range. lower than 2 need to screen for glucocorticoid therapy, malabsorption, hyperparathyroidism, alcoholism


The FRAX tool

eval fracture risk in patients. Based on individual patient models that integrate the risks associated w clinical risk factors as well as BMD of the femoral neck. Gives a 10 yr probability of fracture. 10 year probability of a hip fx and of a major osteoporotic fx like clinical spine, forearm, hip or shoulder


Pathological findings osteoporosis

excessive bone loss results from abnormalities in the bone Remodeling cycle. This involved resorption of old bone by osteoclasts, recruitment of osteoblasts to deposit the new matrix and mineralization of the newly deposited matrix. in osteoporosis a loss of a small amount of bone occurs with EACH CYCLE. Hyperparathyroidism increases the rate of activation of bone remodeling.


DDx in Osteoporosis

osteomalacia, neoplasm (leukemia, myeloma), pagets disease, OI osteogenesis imperfecta inherited connective tissue disorder with many phenotypic presentations -- brittle bone disease


Activity on bone

activity increases BMD modestly


First line therapy medications in osteoporosis

calcium supplements 1,200mg per day. Vitamin D 800 IU per day. Diphosphonates causes decreased osteoclast activity, decreases fractures of hip, spine, and wrist by 50%. ca and vit d for most benefit. weekly Alendronate or Risedronate, monthly Ibandronate is available


second line therapy for osteoporosis

selective estrogen receptor modulators reduce the vertebral fx by 50 percent by have no effect on hip fx. Raloxifene only fda approved selective estrogen receptor modulator for tx osteoporosis


estrogen therapy benefit and risk

reduce risk of fx but increases risk of cardiovascular and thromboembolic events



Inhibits bone resorption by acting on osteoclasts


recombinant parathyroid hormone

results in stimulation of new bone formation, expensive. prescribed by specialists.


Back Pain

most comon musculoskeletal condition, 80% will have back pain at some point. primarily in middle aged adults. Pathologic back pain: originate in the spine or outside the spine. Classified as Traumatic and Atraumatic


Traumatic back pain

fractures, microfractures (causes severe and immediate back pain), dislocations, herniated discs, ligament tears


Atraumatic back pain

degen disc disease, degenerative spinal stenosis, inflammatory arthritis, osteoporosis, spondylolysis and spondyylolistehsis, neoplasms, primary or metastatic tumor, infection


mechanical low back pain

structural, spine is not aligned, need a chiropractor. lumbar strain, degenerative disease, discs spondylosis, herniated disc, spinal stenosis, osteoporosis, fractures, congenital disease, kyphosis, scoliosis


nonmechanical spine disease

spine aligned -- outside of the bone. neoplasm, MM, metastatic carcinoma, lymphoma and leukemia, spinal cord tumors, infection, osteomylitis, septic discitis, paraspinous abscess, bacterial endocarditis, paget disease


visceral disease

pelvic organs, prostatotis, endometriosis, PID, renal disease, pyelonephritis, aortic aneurism, gi disease, pancreatitis, cholecystitis, penetrating ulcer


risk factors linked to low back pain

smoking, obesity, age, female, strenuous work, low education, workers comp insurance, job dissatisfaction, psych factors including somatization disorder, anxiety, depression


s/s low back pain

low back discomfort, stiffness, numbness. paravertebral muscle spasm, motor weakness, loss of DTR, loss of sensation, clonus, positive babinski sign


hx back pain

dx and radiographs are ineffective, need a thorough hx. objective history taking approach to eliminate the subjective of the patients pain experience. have the patient map out the area of pain instead of merely describing its location


physical exam of spine

begin with inspection of the spine, not any asymmetry of the ribs, flank, pelvis and inspect the natural sagittal curvatures of the patient. Assess ROM and determine local tenderness. Note flexion, extension, lateral bending, and rotation of the lumbosacral spine. elicit paravertebral muscle spasms and percussion tenderness


neuro exam

motor testing, strength testing, DTR, sensation, gait



pain inguinal region. sensory loss in inguinal region. weakness - rarely hip. stretch loss - none.



pain in the back radiating to anterior thigh. sensory loss in anterior thigh. weakness is hip flexion, hip adduction, knee extension. stretch reflex loss is patellar tendon.



pain is back radiating to butt, lateral thigh, lateral calf, dorsum foot, great toe. sensory loss is the lateral calf, dorsum foot, webspace between first and second toe. weakness in the hip abduction, knee flexion, foot dorsiflexion, toe extension and flexion, foot eversion and inversion. internal hamstring stretch reflex loss



pain in back, radiating to butt, lateral or posterior thigh, posterior calf, lateral or plantar foot. sensory loss - posterior calf, lateral or plantar aspect of foot. weakness - hip extension, knee flexion, plantar flexion of foot. stretch loss - achilles tendon



pain: sacral or butt pain radiating into the posterior aspect of the leg or perineum. sensory loss - buttock, perineal and perianal regions. weakness: may be minimal with urinary and fecal incontinence as well as sexual dysfunction. reflex loss - anal wink, bulbocavernosus


labs with back pain

no specific lab tests. if suspect infection, complete blood count and ESR should be ordered.


back pain imaging

use bone scans and radiographs, CT scans only to rule out a specific dx. not necessary for first time back pain esp if caused by a specific minor trauma. if structural abnormality like AS with substantive criteria can get imaging. can detect and localize abnormalities precisely with CT and MRI. CT will show fx or osteoid osteomas. MRI will show marrow abnormalities or soft tissue like mets bone disease. technetium bone scan will show early bone infections and localizing metastatic bone lesions.


tx back pain

can use NSAIDS, supin position and PT. Only 1-2 percent are candidates for surgery. prolonged bed rest not beneficial can do 2-3 days. if plain radiograph normal, can do PT and aerobic conditioning



aimed at increasing endurance and strength, lowers recurrence rate and shortens the history of back pain. work hardening programs. passive modalities of therapy, such as massage, acupuncture, and electrical stimulation can provide immediate relief but they do not help in long term treatment


Medication back pain

NSAIDs are the meds of choice for decreasing inflammation. 4-6 weeks. if resolves, the medication is discontinued. muscle relaxants do not have major role but are helpful with spasm and anxiety. they are the best for short term pain relief. if infection, abx and rest.


radiography for back pain

exact point of pain is the most important facet of the information in fx. soft tissue mass is easily palpated on physical exam may not be seen on plain radiographs, need MRI


for suspected fx, dislocations, bone abnormalities

low kilovoltage to contrast bone and soft tissue. femur, tibia and fibula, radius and ulna require 2 radiographs at 90 degrees to one another (orthogonal projections). joints are imaged in 3 projections (frontal, lateral and oblique)


suspected bone tumor

orthogonal plain radiographs. MRI for detailed information on extent of the lesion and involvement of neighboring structures. CT to show calcified tumor matrix


soft tissue tumor

orthogonal radiograph will show calcification within the lesion if present and the effects on neighobring bony structures. large lesions can be seen on orthogonal radiographs but MRI is better for lesion characterization



orthogonal radiograph show definite bone destruction, sequestrum formation or periosteal reaction without other explanation in the appropriate clinical setting are relatively specific for OM, MRI and nuclear bone scan is more sensitive


arthritis imaging

need 3 views plain radiograph to show cartilage narrowing, erosions, ostephytes, soft tissue calcifications and pattern of joint involvement