Design of custom-made navigational template of femoral head and pilot research in total hip resurfacing arthroplasty

Abstract

Background: To develop a novel custom-made navigational template for accurate prosthesis implantation in total hip resurfacing arthroplasty (THRA) by computer-aided technology. Methods: The template was produced based on data preoperatively acquired from computed tomography (CT) scan. The position of the drill guide was obtained according to the anatomical axis of the femoral neck which was defined by the point of the femoral head center and another point of the femoral neck center. The final direction of the drill guide was confirmed by a valgus angle. The surface of the template was constructed based on the inverse of the femoral neck surface. Then the template was made of acrylate resin by using rapid prototyping (RP) technique. Finally, all the templates were verified in 17 cadavers arranged for THRA and postoperative medical images were employed to evaluate the accuracy and validity of the template. Results: The templates had achieved a high fitting with the femoral neck surface, and there were no guide failures. Postoperative evaluation revealed that the Kirschner-wires pass through the center of the femoral head and femoral neck, presenting a relative expected and acceptable valgus angle to the central axis of the femoral neck. The lateral offset showed the relative valgus angle achieved as expected, the horizontal offset showed that no obvious anteroposterior deviation occured. The comparison between the preoperative Neck-shaft angle (NSA) and the postoperative Stem-shaft angle (SSA) showed there is no significant difference(P > 0.05). Conclusion: The novel custom-made navigational template of femoral head can effectively assist surgeons for accurately implanting the femoral head components to the desired position in THRA.

Clinical applications and prospects of 3D printing guide templates in orthopaedics

“… 2020 Liang J et al. [ 164 ] BMC Surg 17 cadaver Acetabular and femoral stem prostheses for THRA The template of the femoral head can effectively assist surgeons in accurately implanting the femoral head components to the desired position in THRA. 2019 Pijpker PAJ et al.…”

“…Liang et al. [ 164 ] used a guide to assist the surgeon in placing acetabular and femoral stem prostheses in 17 cadavers. The postoperative assessment showed that the Kirschner wires accurately passed through the center of the femoral head and femoral neck and the femoral prosthesis orientation was able to achieve reasonable valgus.…”