To explore the clinical study of 3D printing digital technique assisted with PVP in the treatment of multi-segmental osteoporotic vertebral compression fractures of thoracolumbar vertebrae.

A total of 114 patients with OVCF who were treated in the department of orthopaedics in our hospital from February 2017 to March 2020 were enrolled in the study. Patients of the observation group (n=56) were treated with 3D printing technique and PVP operation, and patients in the control group (n=58) were treated with PVP. The sex, age, course of disease, bone mineral density, bone cement injection volume, fracture site, fracture type, vertebral compression degree and integrity of endplate/posterior wall were compared between the two groups. The puncture location time and fluoroscopy times of patients with different fracture types were recorded. The pain score, function score and imaging index were measured before operation, 1 day and 12 months after operation. The complications such as bone cement leakage and nerve injury were counted during the follow-up period. According to the situation of bone cement leakage, all patients were divided into non-leakage group and leakage group, and the general clinical data of the two groups were compared. the multi-factor Logistic regression models affecting bone cement leakage were established respectively, and the model differentiation was evaluated by ROC, and the internal verification was carried out by the method of Bootstrap repeated sampling.

Compared with those of the control group, the average vertebral body height of the two groups increased significantly at 1 day and 12 months after operation, while the vertebral compression ratio, VAS score, Cobb angle and ODI score decreased significantly, and the VAS score and ODI at 12 months after operation were significantly lower than those at 1 day after operation (P<0.05). 12 months after operation, there was no neurological injury and bedridden-related complications in both groups; bone cement leakage occurred in 5 patients (9.00%) of the observation group and 22 patients (37.93%) of the control group. There was significant difference in bone cement leakage between the two groups (χ²=13.259, P<0.001). The amount of bone cement injected, the degree of vertebral compression, the integrity of endplate/posterior wall and the mode of treatment were the influencing factors of bone cement leakage (P<0.05). The model incorporated into the therapeutic technique has higher predictive value.

3D printing technique combined with PVP can reduce the intraoperative puncture time and fluoroscopy times of OVCF, especially flat and double concave fractures, improve the postoperative VAS and ODI.