Table 1.

Selection criteria

Inclusion criteria

1. Treatment for OVCF at our clinic during the data accumulation period

2. Follow-up period > 12 months

3. Recent OVCF at ≥ 1 level on a simple radiograph and CT or MRI

4. No other abnormal findings of the spine (e.g., infection, tumor)

5. Full understanding of the study and voluntary granting of written consent

6. Low serum vitamin D level (< 30 ng/mL)

Exclusion criteria

1. Daily intake ≥ 800 IU of vitamin D3

2. Serum calcium level > 10.5 mg/dL

3. Hypercalciuria (i.e., spot urine calcium/creatinine ratio > 0.4)

4. Malabsorption disease, lymphoma, sarcoidosis, tuberculosis, hyperparathyroidism, celiac disease

5. Kidney stone

6. Renal dysfunction (GFR < 30 mL/min/1.73 m2)

7. Hepatic dysfunction

8. Fasting blood sugar level > 126 mg/dL

9. Previous spine surgery

10. Secondary gain such as worker compensation and traffic insurance

11. Contraindication to vitamin D supplementation

OVCF, osteoporotic vertebral compression fracture; CT, computed tomography; MRI, magnetic resonance imaging; GFR, glomerular filtration rate