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Osteoporosis: Diagnosis & Treatment Karen E. Fields, M.S.P.A.S., PA-C Orthopaedic Surgery and Sports Medicine

Osteoporosis OS is a systemic skeletal disease characterized by diminished bone strength which occurs through lowered bone mass and changes in the microarchitecture of bone tissue. This leads to spinal deformity and increased fracture risk

OS- Why Should We Care? Affects at least 10 million Americans and some sources say 20 million Female predominance (~80%) with most women undiagnosed. OSTEOPOROSIS IS PREVENTABLE

Osteoporosis- Why Should We Care? Osteoporotic fractures occur more frequently than stroke, heart attacks, and breast cancer combined. Long-term affects can be debilitating or deadly: 35-50% of Pts with hip fracture lose ability to ambulate well, 20% become housebound, and 20% may move into SNFs. Rate of death from hip fracture at one year from date of fracture is 15-35%.

Bone Physiology: What’s Normal? Bone is constantly turned over by osteoclasts which break down bone and osteoblasts, which form new bone. The process cycles every 2 years to turn over all the old bone in the skeleton. From childhood until age 30, bone is formed faster than or at the same rate as it is broken down, resulting in skeletal growth (until skeletal maturity) and then in no net change in bone mass.

"After age 30," After age 30, the process begins to reverse and is seen in both men and women. For women, this process accelerates at menopause due to decrease in Estrogen hormones. Men experience a more gradual decline in bone mass throughout their lives. Too much bone loss leads to osteoporosis!

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Types of Osteoporosis Type I: Post-menopausal type Affects Women ages 50-75 and is secondary to decreased estrogen levels. Trabecular bone is lost at a faster rate than Cortical bone.  Type II: Age Related type Affects both men and women as they age. Trabecular and Cortical bone lost at approximately the same rate.

Pathophysiology: TYPE I For the first 5-10 years after menopause, trabecular bone is lost faster than cortical at rates of 2-4% and 1-2% respectively Women can lose 10-15% cortical and 25-30% of trabecular bone in the years immediately following menopause. Estrogen deficiency may increase the production of bone-resorbing cytokines (IL-1, IL-6, TNF) as well as osteoprotegerin which acts to decrease the the production of osteoclasts and bone resorption.

Pathophysiology: TYPE I Estrogen deficiency also reduces production of growth factors that stimulate bone formation and increases the sensitivity of bone to PTH. Osteoblasts have been found to have Estrogen receptors suggesting that estrogen deficiency directly affects new bone formation. Commonly seen are vertebral and Colle’s (distal radius) fractures.

Pathophysiology: TYPE II Once the rapid period of bone loss directly after menopause ends, bone loss occurs more gradually, affecting both men and women. Factors thought to mediate Type II include: A defect in the ability of the kidney to manufacture 1,25-dihydroxyvitamin D or a decrease in the body’s sensitivity leading to A decrease in absorption of Ca2+ from the intestine Mild secondary hyperparathyroidism A decrease in osteoblastic bone formation. Commonly seen fractures: hip, pelvis, wrist, proximal tibia and humerus, and vertebral bodies.

"Type I OS:" Type I OS: Estrogen Def. leads to bone loss, increases serum Ca2+. This decreases the levels of PTH in the blood, causing the kidney to decrease 1,25(0H)2D formation, Leading to decrease in amount of Ca2+ absorbed through the gut.

"Type II OS:" Type II OS: Kidneys decrease formation of 1,25(0H)2D Decreased Ca2+ absorbed thru gut Increased PTH leading to greater bone turnover to increased serum Ca levels

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Osteoporosis:  Frail & Thin Bony Trabeculae, With Larger Pores

Risk Factors for Osteoporosis Non-Modifiable Advancing Age Female Gender Caucasian/Asian Race Family hx of dz Family hx of hip fracture Lactose intolerance Vitamin D resistance Modifiable Smoking Low Ca2+ intake Sedentary Lifestyle Low Body weight Low vitamin D intake or sunlight exposure Stress/depression

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Risk of Fractures from OS After wrist fracture 1.6x RR increase of 2nd fragility fracture After hip fracture 10.4% have a fragility fracture within 1 yr Spine, wrist, hip Up to 20.1% within 2 years

"Back pain ->" Back pain -> Spinal Deformity -> Decr Lung Capacity -> Impaired Function -> Loss of Appetite -> Sleep Problems -> Decreased Activity -> More Bone Loss -> Increased Fracture Risk -> Increased Lung Problems and Comorbidities -> 23% INCREASED MORTALITY

Making the Diagnosis DEXA Scan- Dual-Energy X-Ray Absorptiometry: This test measures bone mineral density (BMD) at the hip and spine. Portable DEXA or U/S: Measures BMD at peripheral sites such as the hand or heel. This is less accurate and usually used as a screening tool for whether someone should have DEXA scan. Fracture An elderly man or post-menopausal woman can be diagnosed after a fragility fracture: hip, vertebral, or distal radius fractures which are pathognomonic of OS in this population.

DEXA DEXA is method of choice for BMD testing. Measures lumbar spine and femoral neck. Has less radiation dose, higher precision, rapid examination time, and lower cost than other modalities of testing.

DEXA Scan:

WHO Criteria for BMD Testing Anyone sustaining a pathognomonic fx Anyone with loss of height of >2” or vertebral compression fractures (kyphosis or dowager’s hump) Women over age 65 Post-menopausal women <65 with risk factors for osteoporosis Patients on glucocorticoids or with primary hyperparathyroidism Pts considering drug therapy Patients being treated for osteoporosis

Interpreting DEXA Results T-Score: measures current BMD and compares to Peak BMD of healthy 20-30 year olds subjects. Z-Score: measures current BMD and compares to BMD of age-matched subjects. Risk of fracture at a certain site is best assessed by BMD taken at that site rather than predicting based on measurements at other sites.

Interpreting DEXA Results Osteopenia: defined by WHO as BMD between 1 and 2.5 SD below peak bone mass. Osteoporosis: defined as BMD below 2.5 SD below peak bone mass. Severe Osteoporosis or Established Osteoporosis is BMD 2.5 SD below mean and presence of one or more fragility fractures. For every 1 SD below normal, risk of fracture increases by 50%.

Orthopaedics & Osteoporosis In Orthopaedics, undertreatment is common Assumption:  primary care physician is responsible Reality: Orthopaedists often see these patients acutely for fracture care and can easily set-up ongoing care Osteoporosis is responsible for 1.3 million fractures each year and Orthopaedists treat most of these!

Undertreatment of OS Of 1162 women over 55 with a single wrist fracture: Only 2.8% had had a DEXA scan prior to injury 22.9% had been started on medication Mostly were only on Calcium supplementation Need to Think of OS in any woman over 50 and any man over 70-75!

Prevention of OS: Exercise (weight bearing forms) Use of estrogen If menopausal AND if there are no contraindications ­ Calcium intake to appropriate amount Vitamin D (from supplement or >15 min sunlight/day) Avoid tobacco Early Detection of Osteopenia

Initial Prevention and Treatment Nutritional support and proper supplementation Begin an exercise program Increases flexibility and strength Prevent falls Home safety Canes, Walkers for increased stability. Proper snow shoveling and salting in winter!

Preventing Falls and Fractures: Good Posture and bending/lifting techniques Home Safety: Eliminate rugs or secure properly Use night lights or flashlights at night Use hand rails on stairs Keep cords and clutter out of walk ways, especially when using walker/canes Get help for hard jobs: moving furniture, opening stuck windows Grab bars around toilet and tub Keep frequently used items between eye level and hip height Eliminate stairs as much as possible

Treatment of OS: Cannot reverse established OS Early intervention can prevent or halt progression. Correct any underlying causes Choice of treatment will depend on cause and stage.

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Medication Treatment Options Bisphosphonates: most commonly prescribed Estrogen preparations: recommended only if okayed by OB/Gyn or PCP and in the absence of other contraindications SERMs: Selective Estrogen Receptor Modulators Calcitonin preparations. Calcium and Vitamin D

How Much Calcium Do I Need? Children 800 mg/day Adolescents 1500 Up to age 50 1000 Over 50, HRT 1000 Over 50 1500 Lactating women 1800

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Vitamin D Plays a very important role in absorption of calcium in the GI tract. Deficiency is common but rarely diagnosed. RDA for Adults 19-50: 200 IU/d 51-70: 400 IU/d >70: 600 IU/d Dose of 800 IU/d will dramatically reduce incidence of OS fractures and is recommended for all adults, especially the elderly!

Bisphosphonates Affects the “balance” of bone metabolism; NOT a hormone Bind tightly and inhibit osteoclastic bone resorption. They not only stop decrease but increase BMD at spine and hip equal to the effects of estrogen. Randomized trials showed 30-50% reduction in vertebral and nonvertebral fractures including hip fxs. In one study, alendronate 5mg qD was shown to increase BMD of lumbar spine, proximal femur and total body in early post-menopausal women. Bone loss will resume after d/c of therapy.

Bisphosphonates: Take with Care Fosamax 70mg or Actonel 30mg once weekly Must Instruct patients on how to take correctly: Taken on an empty stomach first thing in the morning Full 6-8oz glass of water Do not eat or lie down for ½ hour

Bisphosphonates: Take with Care Ensure Adequate Vit D and Ca2+ intake. Correct preexisting hypocalcemia before beginning medication therapy Prescribe cautiously in patients with Upper GI disease and severe renal impairment (CrCl <30 mL/min) Watch for Adverse Reactions: GI upset, abdominal pain, arthralgia, and rarely, dysphagia, esphagitis, gastric ulcer Separate from antacid medication doses by 2 hours (those containing aluminum or magnesium, iron, calcium).

SERMs: EVISTA Bind to estrogen receptor and exert an estrogen-like effect on bone tissue. Can increase BMD by 30-50% and decreases spinal fxs though did not show effect on hip or nonvertebral fxs. Can be used in prevention and treatment of OS in postmenopausal women. 60mg once daily. Contraindicated in pts with h/o VTE May cause: hot flashes, leg cramps, rarely DVT. Interacts with warfarin which needs to be closely monitored

Calcitonin Calcitonin naturally inhibits osteoclasts but not shown to be its key function in the body. Miacalcin: a nasal spray preparation of Calcitonin. Had only a small effect on spine BMD with less than ½ of pts showing an increase compared to 90% response rate with estrogen and bisphosphonates. Side effects included nasal mucosal irritation, flushing, and nausea. Limited use at best in OS

Estrogens: Estrogens inhibit osteoclasts and therefore, reduce bone resorption. It prevents both cortical and trabecular bone loss, reducing risk of all OS fxs. Most beneficial if started in the first years of menopause. Increases risks of BrCA, CV disease, and dementia may outweigh benefits- discuss with OB/GYN.

Fractures from OS 1. Hip 2. Vertebral Compression 3. Colle’s/Distal Radius (4. Proximal Humerus) (5. Proximal Tibia) (6. Pelvic)

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Spinal Fractures and Kyphosis

"Back pain ->" Back pain -> Spinal Deformity -> Decr Lung Capacity -> Impaired Function -> Loss of Appetite -> Sleep Problems -> Decreased Activity -> More Bone Loss -> Increased Fracture Risk -> Increased Lung Problems and Comorbidities -> 23% INCREASED MORTALITY

Vertebral Compression Fracture

Compression Fracture Treatment

Compression Fracture Treatment

What’s Your Diagnosis 1. Mrs. Doe  DEXA done 7/29/03 T-Score of -2.3, Z-score of -0.9 2. Mrs. Smith   DEXA 7/30/02 T-Score of -2.6, Z-Score -1.2 3. Ms. Jones   DEXA 12/20/03 T-Score of -3.0, Z Score -1.9 4. Mrs. Martinez   DEXA 1/6/04 T Score of -0.6, Z score of -0.8

Case Study 49 y/o Caucasian Female Sustained a Trimalleolar Ankle Fracture while running along the river Allergies, PMH, Meds all negative. Past Surgical significant for appy and breast lumpectomy. Menopause began at age 46. Mother and sister have h/o OS. Smokes ½ ppd x 5 years with prior h/o 1ppd x16 yrs

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What I Can Do: Orthopaedics play a proactive role Utilize clinic setting and role as a MD/PA/NP to start the process. Liberal samples and yearly Rx for mail order Maximize nutrition in all patients, including kids, teens, and young adults. Calcium (1000-1500mg daily for adults) Vitamin D (400-800 IU daily for adults) Proper Screening: DEXA scanning q2 yrs Record accurate height yearly

What You Can Do: Think of OS in all your patients over 50! Ask pertinent questions of patients when getting a health history Begin a screening questionnaire in your office and go through it with your patients Be available for assisting in counseling patients. INFORM YOUR PATIENTS!