China has gradually entered an aging society, and the incidence of osteoporotic fractures is increasing rapidly. Although the harm of osteoporotic fracture is huge, its diagnostic rate in China is still low. China still lacks a national osteoporotic fracture registration system, which has been established in many countries. The purpose of this study is to establish a Chinese osteoporotic fracture registration network platform (CORN), which will be helpful for the long-term comprehensive management of osteoporotic fracture population in China. This platform will help to establish a large prospective clinical cohort database of osteoporotic fractures and high-risk population in China.

Previous studies have shown that the screening, diagnosis and treatment rates of osteoporosis and osteoporotic fracture in China are still low. The goal of this study is to establish a nationwide multicenter osteoporotic fracture registration network platform, a national collaborative network, a large osteoporotic fracture research cohort and a national biological specimen bank in Chinese mainland.

About 100 hospitals covering 20 provinces, autonomous regions and municipalities will be selected as collaborators. Each collaborator is going to enroll at least 500 patients with osteoporotic fractures on average, and a total of 50000 subjects are planned to be enrolled in our study.

Subjects will be assessed as follows:

1. Questionnaire investigation: including demographic data, past medical history, reproductive history, menstrual/menopausal history, family history of osteoporosis and fractures, awareness of disease, diagnosis and treatment of osteoporotic fractures, etc.
2. Clinical features: including anthropometric data, clinical symptoms, physical examination, grip strength test, balance assessment, walking speed test, etc.
3. Fall risk assessment: assessed by the Short Physical Performance Battery (SPPB), the Falls Risk for Older People in the Community (FROP-Com) and Morse Fall Scale (MFS).
4. Imaging evaluation: including thoracolumbar spine x-ray, bone mineral density (BMD) measurement by dual-energy x-ray absorptiometry (DXA), Quantitative computed tomography (QCT) and high-resolution peripheral quantitative computed tomography (HR-pQCT).
5. Laboratory tests: including blood calcium and phosphorus levels, bone turnover markers, parathyroid hormone level, 25-hydroxyvitamin D, 24-hour urine calcium, etc.
6. Biological specimen collection: blood and urine specimens are plan to be obtained for further studies with informed consent.
7. Follow-ups: subjects will be followed up every 6 months for 3 years.

Inclusion Criteria (any of the following):

• Patients with hip osteoporotic fracture.
• Patients with vertebral osteoporotic fracture.
• Patients with low T-score ( ≤ -2.5) and at least one risk factor (e.g., history of osteoporotic fractures in other sites, a parental history of hip fracture, age ≥ 65 years, BMI < 18.5kg/m2, current smoking).
• Patients with very low T-score (< -3.0).
• The ten year probability of fracture by FRAX: major osteoporosis fracture ≥20%, or hip fracture ≥3%.

Exclusion Criteria:

• Patients who are unwilling to participate in the trial, have poor compliance and do not sign informed consent.
• Patients judged as unqualified participants by clinicians.

Patients at high risk of fracture.