Updated: 11/30/2019

Osteoporosis

Topic
Review Topic
0
0
0%
0%
Questions
6 6
0
0
0%
0%
Evidence
4 4
0
0
Overview
 

 
Snapshot
  • A 67-year-old woman presents to the emergency department after falling while walking down the stairs of her home. She landed on her rear on a carpeted floor and denies hitting her head. She experienced severe pain in her right hip after the fall and is unable to bear weight on the affected side. Menopause began 17 years ago. She has smoked 1-pack of cigarettes for the past 40 years. On physical exam, her right leg is shortened, adducted, and externally rotated. Laboratory testing is unremarkable.
Introduction
  • Clinical definition
    • decreased bone mass (osteopenia) that significantly increases the patient's risk of fracture
  • Epidemiology
    • incidence
      • most common types of osteoporosis are
        • post-menopausal
        • senile
    • risk factors
      • post-menopausal women
      • being ≥ 65 years of age
      • people of Caucasian and Asian descent
      • lifestyle factors such as 
        • poor physical activity
        • vitamin D deficiency and poor calcium intake
        • smoking 
        • alcohol use disorder
      • medications such as
        • warfarin, lithium, proton pump inhibitors, and glucocorticoids
      • hyperparathyroidism
      • hyperthyroidism
      • multiple myeloma
      • malabsorption syndromes
  • Pathogenesis
    • in young adulthood, peak bone mass is achieved and this is determined by a number of factors (e.g., genetics)
      • after this peak bone mass is attained, there is a small decrease in bone formation with every cycle of bone remodeling
        • senile osteoporosis
          • osteoblasts have their biosynthetic and proliferative ability reduced with age
        • poor physical activity
          •  mechanical force on bone stimulates bone remodeling
            • athletes have increased bone density
          • decreased physical activity results in bone loss
        • decreased estrogen levels
          • such as in menopause, decreased estrogen levels increase bone resportion and formation
            • however, the rate of formation is less than resorption resulting in a net bone loss
            • increased osteoclast activity is significant in areas of bone with large surface area
              • such as the vertebral bodies, leading to vertebral compression fractures 
        • there is trabecular and cortical bone loss 
  • Prognosis
    • generally good if detected early and appropriately managed
Presentation
  • Symptoms
    • fractures (e.g., vertberal and hip), otherwise, patients are typically asymptomatic
  • Physical exam
    • may see loss in height
Imaging
  • DEXA
    • indication
      • all women ≥ 65 and all men ≥ 70 years of age 
      • smoking and sedentary lifestyles are risk factors
    • notes
      • T-score ≤ -2.5
Studies
  • Labs
    • serum calcium, phosphorus, parathyroid hormone, and alkaline phosphatase are normal
  • Histology
    • histologically normal; however, there is a decreased quantity of normal bone
Differential
 
Laboratory Abnormalities in Select Bone Disorders
Etiology
Serum Phosphate
Serum Calcium
Serum Alkaline Phosphatase
Parathyroid Hormone
Osteomalacia / rickets  Decreased Decreased Increased Increased
Osteoporosis   Normal Normal Normal Normal
Osteopetrosis  Normal Normal or decreased Normal Normal
Paget disease of the bone  Normal Normal Elevated Normal
Osteitis fibrosa cystica  Primary
• hyperparathyroidism- decreased
Secondary
• hyperparathyroidism
increased
Primary
• hyperparathyroidism
increased
Secondary
• hyperparathyroidism
decreased
Primary and secondary hyperparathyroidism
increased
Primary and secondary hyperparathyroidism
increas
ed
Hypervitaminosis D Increased Increased Normal Decreased
 
Treatment
  • Conservative
    • calcium and vitamin D supplementation
    • strength training
    • smoking cessation
  • Medical
    • bisphosphonates 
      • indication
        • first-line for pharmacologic therapy in osteoporosis
    • raloxifene 
      • second line therapy for osteoporosis
      • can cause hot flashes and venous thromboembolism 
      • does not cause endometrial hyperplasia or increase risk of breast cancer
    • teriparatide
      • indication
        • considered first-line in patients with a very high risk of fracture
Complications
  • Fractures
 

Please rate topic.

Average 4.8 of 6 Ratings

Thank you for rating! Please vote below and help us build the most advanced adaptive learning platform in medicine

The complexity of this topic is appropriate for?
How important is this topic for board examinations?
How important is this topic for clinical practice?
Questions (6)
Lab Values
Blood, Plasma, Serum Reference Range
ALT 8-20 U/L
Amylase, serum 25-125 U/L
AST 8-20 U/L
Bilirubin, serum (adult) Total // Direct 0.1-1.0 mg/dL // 0.0-0.3 mg/dL
Calcium, serum (Ca2+) 8.4-10.2 mg/dL
Cholesterol, serum Rec: < 200 mg/dL
Cortisol, serum 0800 h: 5-23 μg/dL //1600 h:
3-15 μg/dL
2000 h: ≤ 50% of 0800 h
Creatine kinase, serum Male: 25-90 U/L
Female: 10-70 U/L
Creatinine, serum 0.6-1.2 mg/dL
Electrolytes, serum  
Sodium (Na+) 136-145 mEq/L
Chloride (Cl-) 95-105 mEq/L
Potassium (K+) 3.5-5.0 mEq/L
Bicarbonate (HCO3-) 22-28 mEq/L
Magnesium (Mg2+) 1.5-2.0 mEq/L
Estriol, total, serum (in pregnancy)  
24-28 wks // 32-36 wks 30-170 ng/mL // 60-280 ng/mL
28-32 wk // 36-40 wks 40-220 ng/mL // 80-350 ng/mL
Ferritin, serum Male: 15-200 ng/mL
Female: 12-150 ng/mL
Follicle-stimulating hormone, serum/plasma Male: 4-25 mIU/mL
Female: premenopause: 4-30 mIU/mL
midcycle peak: 10-90 mIU/mL
postmenopause: 40-250
pH 7.35-7.45
PCO2 33-45 mmHg
PO2 75-105 mmHg
Glucose, serum Fasting: 70-110 mg/dL
2-h postprandial:<120 mg/dL
Growth hormone - arginine stimulation Fasting: <5 ng/mL
Provocative stimuli: > 7ng/mL
Immunoglobulins, serum  
IgA 76-390 mg/dL
IgE 0-380 IU/mL
IgG 650-1500 mg/dL
IgM 40-345 mg/dL
Iron 50-170 μg/dL
Lactate dehydrogenase, serum 45-90 U/L
Luteinizing hormone, serum/plasma Male: 6-23 mIU/mL
Female: follicular phase: 5-30 mIU/mL
midcycle: 75-150 mIU/mL
postmenopause 30-200 mIU/mL
Osmolality, serum 275-295 mOsmol/kd H2O
Parathyroid hormone, serume, N-terminal 230-630 pg/mL
Phosphatase (alkaline), serum (p-NPP at 30° C) 20-70 U/L
Phosphorus (inorganic), serum 3.0-4.5 mg/dL
Prolactin, serum (hPRL) < 20 ng/mL
Proteins, serum  
Total (recumbent) 6.0-7.8 g/dL
Albumin 3.5-5.5 g/dL
Globulin 2.3-3.5 g/dL
Thyroid-stimulating hormone, serum or plasma .5-5.0 μU/mL
Thyroidal iodine (123I) uptake 8%-30% of administered dose/24h
Thyroxine (T4), serum 5-12 μg/dL
Triglycerides, serum 35-160 mg/dL
Triiodothyronine (T3), serum (RIA) 115-190 ng/dL
Triiodothyronine (T3) resin uptake 25%-35%
Urea nitrogen, serum 7-18 mg/dL
Uric acid, serum 3.0-8.2 mg/dL
Hematologic Reference Range
Bleeding time 2-7 minutes
Erythrocyte count Male: 4.3-5.9 million/mm3
Female: 3.5-5.5 million mm3
Erythrocyte sedimentation rate (Westergren) Male: 0-15 mm/h
Female: 0-20 mm/h
Hematocrit Male: 41%-53%
Female: 36%-46%
Hemoglobin A1c ≤ 6 %
Hemoglobin, blood Male: 13.5-17.5 g/dL
Female: 12.0-16.0 g/dL
Hemoglobin, plasma 1-4 mg/dL
Leukocyte count and differential  
Leukocyte count 4,500-11,000/mm3
Segmented neutrophils 54%-62%
Bands 3%-5%
Eosinophils 1%-3%
Basophils 0%-0.75%
Lymphocytes 25%-33%
Monocytes 3%-7%
Mean corpuscular hemoglobin 25.4-34.6 pg/cell
Mean corpuscular hemoglobin concentration 31%-36% Hb/cell
Mean corpuscular volume 80-100 μm3
Partial thromboplastin time (activated) 25-40 seconds
Platelet count 150,000-400,000/mm3
Prothrombin time 11-15 seconds
Reticulocyte count 0.5%-1.5% of red cells
Thrombin time < 2 seconds deviation from control
Volume  
Plasma Male: 25-43 mL/kg
Female: 28-45 mL/kg
Red cell Male: 20-36 mL/kg
Female: 19-31 mL/kg
Cerebrospinal Fluid Reference Range
Cell count 0-5/mm3
Chloride 118-132 mEq/L
Gamma globulin 3%-12% total proteins
Glucose 40-70 mg/dL
Pressure 70-180 mm H2O
Proteins, total < 40 mg/dL
Sweat Reference Range
Chloride 0-35 mmol/L
Urine  
Calcium 100-300 mg/24 h
Chloride Varies with intake
Creatinine clearance Male: 97-137 mL/min
Female: 88-128 mL/min
Estriol, total (in pregnancy)  
30 wks 6-18 mg/24 h
35 wks 9-28 mg/24 h
40 wks 13-42 mg/24 h
17-Hydroxycorticosteroids Male: 3.0-10.0 mg/24 h
Female: 2.0-8.0 mg/24 h
17-Ketosteroids, total Male: 8-20 mg/24 h
Female: 6-15 mg/24 h
Osmolality 50-1400 mOsmol/kg H2O
Oxalate 8-40 μg/mL
Potassium Varies with diet
Proteins, total < 150 mg/24 h
Sodium Varies with diet
Uric acid Varies with diet
Body Mass Index (BMI) Adult: 19-25 kg/m2
Calculator

Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK
Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK
Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK

You have 100% on this question.
Just skip this one for now.

(M2.OR.4754) A 64-year-old female presents to her primary care physician for an annual checkup. She states that her health is adequate, but she has not been doing well since her husband died last year. She is able to get by but admits to having trouble caring for herself, cooking, cleaning, and paying her bills. The patient complains of diffuse muscle aches and pains. She has a past medical history of anxiety and seasonal affective disorder. She is not currently taking any medications. On physical exam, you note a gaunt woman with a depressed affect. You note that her body mass index (BMI) and height have both decreased since her last annual visit. On physical exam, her cardiac, pulmonary, and abdominal exams are within normal limits. Lab work is drawn and is as follows:

Serum:
Na+: 135 mEq/L
K+: 3.7 mEq/L
Cl-: 100 mEq/L
HCO3-: 23 mEq/L
Urea nitrogen: 7 mg/dL
Glucose: 70 mg/dL
Creatinine: 0.8 mg/dL
Ca2+: 8.0 mg/dL
Mg2+: 1.5 mEq/L
Parathyroid hormone: 855 pg/mL
Alkaline phosphatase: 135 U/L
Phosphorus: 2.6 mg/dL

Hemoglobin: 14 g/dL
Hematocrit: 36%
Platelet count: 187,000/mm^3
Leukocyte count: 4,700/mm^3

What is the most likely diagnosis?
Review Topic | Tested Concept

QID: 108976
1

Osteopenia

4%

(2/45)

2

Osteoporosis

7%

(3/45)

3

Osteomalacia

47%

(21/45)

4

Hyperparathyroidism

27%

(12/45)

5

Clinical malnutrition

9%

(4/45)

M2 D

Select Answer to see Preferred Response

You have 100% on this question.
Just skip this one for now.

(M2.OR.37) A 67-year-old Caucasian female presents to her primary care physician after a screening DEXA scan reveals a T-score of -3.0. Laboratory work-up reveals normal serum calcium, phosphate, vitamin D, and PTH levels. She smokes 1-2 cigarettes per day. Which of the following measures would have reduced this patient's risk of developing osteoporosis? Review Topic | Tested Concept

QID: 102978
1

Reduced physical activity to decrease the chance of a fall

0%

(0/12)

2

Initiating a swimming exercise program three days per week

75%

(9/12)

3

Intranasal calcitonin therapy

0%

(0/12)

4

Calcium and vitamin D supplementation

17%

(2/12)

5

Weight loss

0%

(0/12)

M2 C

Select Answer to see Preferred Response

You have 100% on this question.
Just skip this one for now.

(M3.OR.10) A 47-year-old African-American woman presents to her primary care physician for a general checkup appointment. She works as a middle school teacher and has a 25 pack-year smoking history. She has a body mass index (BMI) of 22 kg/m^2 and is a vegetarian. Her last menstrual period was 1 week ago. Her current medications include oral contraceptive pills. Which of the following is a risk factor for osteoporosis in this patient? Review Topic | Tested Concept

QID: 102951
1

Age

0%

(0/2)

2

Body mass index

0%

(0/2)

3

Estrogen therapy

0%

(0/2)

4

Race

0%

(0/2)

5

Smoking history

100%

(2/2)

M2 D

Select Answer to see Preferred Response

Evidences (5)
Topic COMMENTS (24)
Private Note