Prediction of the Collapse of Necrotic Femoral Head Using Computed Tomography Scan and X-ray Before Hip Arthroplasty

Prediction of the Collapse of Necrotic Femoral Head Using Computed Tomography Scan and X-ray Before Hip Arthroplasty

Prediction of the Collapse of Necrotic Femoral Head Using Computed Tomography Scan and X-ray Before Hip Arthroplasty: Study Protocol for a Single-center, Open-label, Diagnostic Trial

To verify that CT scan and X-ray can predict the collapse of the necrotic femoral head before hip arthroplasty and effectively guide the surgical management.

Osteonecrosis of the femoral head (ONFH) is a common and frequently occurring disease. The main clinical manifestations are hip pain and dysfunction. The etiology and pathogenesis of ONFH caused by various reasons are the problems that have not been solved yet in the field of orthopedics. If want to achieve satisfactory therapeutic effect, surgical choice is essential. It is very important for prognosis to master the indications of operation and take appropriate treatment measures, especially the great difference between palliative surgery and hip arthroplasty. To determine whether the femoral head collapses and the degree of collapse of the articular cartilage of the femoral head can help physicians to select an optimal surgical plan. Chinese scholars commonly believe that if the femoral head collapse is less than 2 mm, investigators can choose autologous bone graft, allogeneic bone graft and other palliative surgery. If the femoral head collapse is more than 2 mm, investigators can choose total hip arthroplasty. However, above standard has not been extensively accepted worldwide.

In the X-ray group, the changes in femoral head height were measured with X-ray in an anteroposterior position of the pelvis (healthy and affected sides of the hip) at preoperative 1 week.

In the CT group, changes of femoral head height were measured with CT scan on bilateral hips (healthy side and affected side) at preoperative 1 week.

In the specimen group, femoral head on the affected side was resected during surgery and directly measured with a ruler and vernier caliper.

In the X-ray group, the changes in femoral head height were measured with X-ray in an anteroposterior position of the pelvis (healthy and affected sides of the hip) at preoperative 1 week

In the CT group, changes of femoral head height were measured with CT scan on bilateral hips (healthy side and affected side) at preoperative 1 week

In the specimen group, femoral head on the affected side was resected during surgery and directly measured with a ruler and vernier caliper.

Sensitivity refers to true positive rate, the percentage of patients with actual illness who was correctly diagnosed in overall patients. High sensitivity indicated high correct rate of femoral head collapse.

Specificity refers to true negative rate, the percentage of patients with actual disease-free who are correctly judged as disease-free according to the diagnostic criteria. The high specificity indicates high accuracy of diagnosis.

Positive predictive value refers to the proportion of patients with actual illness among all positive cases, can reflect the possibility of affecting target disease in patients with positive screening test result.

Negative predictive value refers to the proportion of patients with negative screening test result who do not suffer from diseases.

Inclusion Criteria: Unilateral ONFH confirmed preoperatively (FICAT stages III and IV; Appendix 1)14 Unilateral total hip arthroplasty Age range: 32-68 years Irrespective of sex Sign the informed consent Exclusion Criteria: Infection Tuberculosis Tumor Severe osteoporosis