[Application of the computer-assisted virtual reduction combined with 3D printing technique in acetabular fractures].

Objective: To investigate the computer-assisted virtual reduction combined with 3D printing technique as preoperative planning and assess their therapeutic effects.

Methods: Thirty-five cases of acetabular fracture treated by internal fixation from March 2011 and March 2014 were retrospectively analyzed. All patients underwent operations with internal fixations implanted. The patients were divided into 2 groups according whether they used the computer-assisted virtual reduction combined with 3D printing technology. Fifteen patients in the digital group included 9 males and 6 females with a mean age of (39.4±8.8) years old ranging from 22 to 58 years old;time from injury to the operation was (8.8±2.0) days;for Letournel-Judet classification, 4 cases were both column fracture, 5 cases were posterior wall fracture, 4 cases were T-fracture, 2 cases were posterior wall with transverse fracture. Twenty cases in the control group included 12 males and 8 females with a mean age of (38.7±13.1) years old ranging from 19 to 59 years old;time from injury to the operation was(8.2±2.3) days;for Letournel-Judet classification, 6 cases were both column fracture, 8 cases were posterior wall fracture, 3 cases were T-fracture, 3 cases were posterior wall with transverse fracture. The volume of intraoperative blood loss and blood transfusion, operative time, satisfaction rate of fracture reduction and excellent and good rate of d`Aubigne Postal function evaluation were compared between the two groups and statistical analysis was conducted.

Results: All the incisions healed without infection occurred. All the fractures healed without breakage or loosening of plates and screws. There was 1 case of postoperative nerve stimulation symptoms in each group. One patient in the digital group was found necrosis of the femoral head at 6 months after operation. One patient in the control group was found heterotopic ossification at 8 months after operation. All patients were follow-up for 13 to 28 months with an average of 17.6 months. The volume of intraoperative blood loss and blood transfusion in the digital group were significantly less than those in the control group(<0.05). The operation time in the digital group was shorter than that in the control group(<0.05). The excellent and good rates of fracture reduction were 92.9%(14/15) and 85%(17/20) in the digital group and the control group respectively, and there was no statistical significance (>0.05). The excellent and good rates of Aubigne Postal function evaluation were 86.7%(13/15) and 80%(16/20) respectively, and there was no significant difference(>0.05).

Conclusions: The computer-assisted virtual reduction combined with 3D printing technique can reduce the operative time, volume of intraoperative blood loss and blood transfusion in acetabular surgeries for patients with acetabular fractures. The technique is an effective method for preoperative planning, which worth promoting.