Application of 3D printing technology on the treatment of complex proximal humeral fractures (Neer3-part and 4-part) in old people.

PURPOSE: This study was conducted to investigate the feasibility and clinical potential of using the 3D printing technology (3DPT) versus typical strategy (thin-layer CT scan) for the treatment of complicated proximal humeral fractures (PHFs) in old people.

METHODS: Sixty-six old patients age ranging from 61 to 76 years with persistent complicated PHFs were randomly assigned to two groups as per the controlled randomization table (34 cases in the test group and 32 cases in the control group). In the test group, 3DPT was applied to build the 3D facture model of a patient, according to the data acquired from the thin-layer CT scan and subsequently processed with Mimics software. This helped to confirm the diagnosis, design the individual operation plan, simulate the surgical procedures and perform the surgery as plan. In the control group, only thin-layer CT scan was applied for the design of the operation plan prior to the surgery. Here, parameters including surgery duration, blood loss volume during surgery, the number of fluoroscopy, time to union were statistically analyzed for two groups after the operation. The screw lengths designed before the surgery and measured during the surgery were compared.

RESULTS: The 3D PHF model generated using 3DPT was able to provide the visual display and omni-directional observation of the direction and severity of the fracture dislocation, which facilitated preoperative diagnosis, operation planning and design, data measurement, preselection of internal fixator and surgical outcome simulation. According to the follow-up ranging from 12∼28 months for the 66 patients, the results showed no significant difference in time to union between the two groups (P>0.05). Apart from that, less surgery duration, less blood loss during surgery, less number of fluoroscopy can be observed compared with the control group (P<0.05).

CONCLUSIONS: In this study, 3DPT showed great clinical feasibility of the treatment of complicated PHFs. The 3D-print PHF model had the ability to clearly display the fracture and thus was useful to determine the fracture classification and the magnitude of fracture injury. It benefited surgeons to gain a better understanding of complicated PHFs, design a most suitable operation plan prior to surgery and facilitate the doctor-patient communication. This therefore enabled the reduction of intraoperative injury and the optimization of surgical outcomes.