To investigate the efficacy of CT scanning for 3D reconstruction and 3D printing in the internal fixation for in situ femoral condyle fractures.

A retrospective study was conducted of the 111 patients with in situ femoral condyle fracture who had been treated by internal fixation at Department of Traumatic Orthopaedics, The First People＇s Hospital of Hefei from June 2013 to January 2018. They were 59 males and 52 females, aged from 20 to 59 years(average, 47 years). In 74 of them (observation group), the internal fixation was assisted by 3D printing using 3D images. There were 38 males and 36 females with an age of 44.5±4.7 years; there were 20 cases of type C1, 40 cases of type C2 and 14 cases of type C3 according to the AO classification. In the other 37 patients (control group), the operation was assisted only by 3 D scanning. There were 21 males and 16 females with an age of 43.1±4.6 year; there were 8 cases of type C1, 19 cases of type C2 and 10 cases of type C3 according to the AO classification. The 2 groups were compared in terms of operation time, clinical fracture healing time, intraoperative blood loss, hospital stay, number of fluoroscopy, knee joint score of Hospital for Special Surgery (HSS), fixation modes and postoperative complications.

There were no significant differences in the preoperative general data between the 2 groups, showing comparability (P>0.05). All the patients were followed up for 8 to 12 months (average, 10.6 months). The observation group had significantly shorter operation time (62.3±4.7 minutes), fracture healing time (21.2±3.4 weeks) and hospital stay (14.9±3.3 days) than the control group (89.5±6.0 minutes, 25.1±3.5 weeks, 23.5 ± 3.5 days) (P<0.05). In the observation group, the intraoperative blood loss (84.1±11.1 mL), fluoroscopy number (2.1±0.3 times) and HSS score (94.1±4.2 points) were significantly less than those in the control group (129.6 ± 14.7 mL, 4.7 ± 0.4 times and 86.5 ± 4.6 points) (P<0.05). There were no significant differences between the 2 groups in the use of L type iliac plate, dynamic iliac screws, retrograde interlocking intramedullary nail or minimally invasive internal fixation system (P>0.05). There were no significant differences in abnormal healing, joint adhesion, fixation fracture or incision infection between the 2 groups either (P>0.05).

CT scanning for 3D reconstruction can be used for multi-angle observation of the bone fragments in patients with femoral condyle fracture and 3D printing based on 3D reconstruction for manufacture of physical model of individualized fracture to assist the internal fixation. Combination of the two can help choose an appropriate fixation mode to facilitate fracture reduction.

Femur; Imaging, three-dimensional; Therapy, computer-assisted; In situ femoral condyle fracture; 3D printing