Chapter 7-8: Osteoporotic Compression Fracture

TEXTBOOK PRESENTATION

The classic presentation is acute, severe pain that develops in an older woman and radiates around the flank to the abdomen, occurring either spontaneously or brought on by trivial activity such as minor lifting, bending, or jarring.

DISEASE HIGHLIGHTS

1. Fractures are usually in the mid to lower thoracic or lumbar region.

2. Fractures at T4 or higher are more often due to malignancy than osteoporosis.

3. Pain is often increased by slight movements, such as turning over in bed.

4. Can also be asymptomatic

5. Pain usually improves within 1 week and resolves by 4–6 weeks, but some patients have more chronic pain.

6. Osteoporosis is usually related to menopause and aging.

7. Can occur as a complication of a variety of diseases and medications.

   1. Most common diseases include hyperthyroidism, primary hyperparathyroidism, vitamin D deficiency, hypogonadism, and malabsorption.

   2. Medications that can lead to osteoporosis include corticosteroids (most common), anticonvulsants, aromatase inhibitors, and long-term heparin therapy.

8. Risk factors for osteoporosis include

   1. Age

      1. Strongest risk factor

      2. Relative risk of almost 10 for women aged 70–74 (compared with women under 65), increasing to a relative risk of 22.5 for women over 80

   2. Personal history of rib, spine, wrist, or hip fracture

   3. Current smoking or use of ≥ 3 units of alcohol daily

   4. White, Hispanic, or Asian ethnicity

   5. Weight < 132 lbs

   6. Parental history of hip fracture

9. Bone density testing: The T score is defined as the number of standard deviations different the current bone density is compared to a young adult reference population; a T score ≥ –1.0 is normal, < –1.0 and > –2.5 is osteopenia, and ≤ –2.5 is osteoporosis.

   1. Over 15 years, the absolute risk of vertebral fracture is about 10% for women with T scores of 0 to −1.0 and about 30% for women with T scores of –2.5 or worse.

   2. Women with a prevalent vertebral fracture and a T score > −1.0 have the same absolute risk of subsequent fracture (~25%) as women without prevalent fractures and T scores ≤ −2.5.

   3. The FRAX score, used to estimate the 10-year probability of a hip fracture or a major osteoporotic fracture, is available at http://www.shef.ac.uk/FRAX/

EVIDENCE-BASED DIAGNOSIS

1. History and physical exam

   1. Not well studied

   2. Age > 70 has LR+ of 5.5

   3. History of corticosteroid use has LR+ of 12.0 for diagnosis of osteoporotic compression fracture as a cause of back pain.

   4. Patients with at least 3 typical risk factors (female sex, age over 70, trauma, and use of corticosteroids) have a very high likelihood of having an osteoporotic compression fracture.

2. Imaging

   1. MRI is probably more sensitive and specific than radiographs, but data are not available; most compression fractures are diagnosed with radiographs, unless there is a concern for malignancy.

   2. MRI can distinguish between benign and malignant osteoporotic compression fractures, with sensitivity of 88.5–100% and specificity of 89.5–93% (LR+ = 8–14, LR− = 0–0.12).

   3. Bone scan can be useful for determining acuity.

MRI scan ...