A personalized 3D printed titanium alloy sacral prosthesis

Abstract

The invention discloses an individualized 3D printed titanium alloy sacral prosthesis, which comprises a lumbar joint, an iliac joint and a connecting part. The lumbar junction is a hollow columnar porous structure with a fan-shaped tail fin bionically designed according to the shape of the sacral 1 vertebra, and the osseointegrated surface with the lower endplate of the lumbar 5 vertebra is designed with a porous bone-like trabecular structure, and is designed with 2 screws holes; the iliac joint is a hollow polyhedron designed to imitate the auricular surface of the ilium, and the ilium joint is designed to imitate the porous structure of the trabecular bone, and is designed with four longitudinally symmetrically distributed screw holes; the joint is hollow, Porous, tubular structure that connects the lumbar junction to the iliac junction. The present invention reconstructs the pelvic ring structure through the titanium alloy sacral prosthesis, fixes it with screws and grafts the bone in the hollow structure, so as to achieve the biological healing effect of early mechanical stability and strong later stage; the reconstructed sacral defect has beautiful appearance and mechanical stability, and reduces the distance prosthetic failure rate.

Description

technical field [0001] The invention belongs to the technical field of medical internal fixation manufacturing, and in particular relates to an individualized 3D printed titanium alloy sacral prosthesis for reconstructing the stability of the pelvic ring after total sacral resection. Background technique [0002] The human sacrum consists of 5 sacral vertebrae (sacral 1-sacral 5 vertebral bodies), which are located at the end of the spine, form a strong pelvic ring structure with the bilateral ilium, connect upward to the lumbar spine, and transfer the weight of the upper body to the lower limbs on both sides. Apart from fractures, the most common lesion in the sacrum is tumor (primary tumor or metastases). Although the incidence rate is low, but because it is adjacent to pelvic organs and important vascular and nerve bundles, the lesion often compresses the sacral nerve, causing perineal and perianal numbness, incontinence, and further development can lead to paralysis of t...

AI Technical Summary

Problems solved by technology

However, this kind of mechanical fixation has the following problems because the sacrum is not reconstructed: 1) After the sacrum is resected, a large cavity will be formed locally. If the sacral prosthesis is not implanted, there will be a long-term residual cavity and effusion, which will cause infection; 2) ) Sacral resection will cause pelvic internal organs such as rectum and colon to herniate to the posterior side (dorsal side), resulting in the patient’s stool disorder. 3) The screw and the bone are mechanically connected, and bone growth cannot be performed between the two And to achieve the final biological healing, long-term activities will inevitably lead to the pull out of the screw from the bone and the breakage of the titanium rod / screw

However, the main body of the prosthesis is not customized, and its integration with the lumbar bone surface and later bone ingrowth are worse than those of the 3D printed prosthesis. At the same time, it lacks the structural design to increase the long-term biological fixation of the prosthesis, which may easily lead to internal fixation failure.

To sum up, at present, there is no successful design at home and abroad that not only meets the structural and mechanical requirements of the human body after total sacrectomy, but also promotes the bony fusion of the lumbar spine and bilateral ilium after implantation, thereby rebuilding the mechanical support of the limbs and shortening the recovery time of the patient. Sacral prosthesis for time required for weight bearing and movement

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