Degradable stent for sternum defect repair and manufacturing method thereof

Abstract

The invention discloses a degradable stent for sternum defect repair and a manufacturing method thereof, belonging to the technical field of biomedicines. The degradable stent is characterized in that: the stent is cross-shaped; four end parts which form a cross shape are flat slots with each having a solid core inside, a closed periphery and an opening at the front end; the slots in the longitudinal direction are sternum slots; the slots in the transverse direction are rib slots, and the contours of the inner cavities of the sternum slots and the rib slots are similar to the shapes of sternums and ribs. The manufacturing method of the degradable stent comprises the following steps of: performing CT three-dimensional scanning and duplication on defective sternums and ribs, performing pattern repair on the duplicated defective sternums and ribs, inputting the acquired shape data of integral sternums and ribs into a deposition-type FDM (Fused Deposition Modeling) rapid modeling machine, and substituted members of the integral sternums and ribs are duplicated by using a fused deposition free manufacturing technology. The degradable stent has the advantages of small irritation to tissues and strong anti-infection ability; besides, the unique personalized design of the degradable stent can restore the biological morphology and functions of a receptor to a maximal extent; and by using the degradable stent, complexity and difficulty in former operations are avoided, the operation time is shortened and the operation efficiency is increased.

Description

technical field [0001] The invention belongs to the technical field of biomedicine and relates to the technology of repairing and treating sternal defect, specifically a degradable support for repairing sternal defect and a manufacturing method thereof. Background technique [0002] The sternum is a flat bone located in the middle of the anterior chest wall, shaped like a short sword, and divided into three parts: hilt, body, and xiphoid process. Both sides of the sternum are connected with the ribs to form the thorax, which plays an important role in protecting the mediastinum and internal organs of the thoracic cavity. Common diseases of the sternum, such as sternal tumors, infections, radiation ulcers, trauma, and congenital deformities, often require surgical treatment, resulting in sternal defects and damage to the integrity, stability, and protection of the mediastinal organs. endanger the life of the patient. The sternum needs to be reconstructed. At present, there ...

AI Technical Summary

Problems solved by technology

[0004] 1. Autologous tissue. It has a wide range of sources, is convenient to obtain materials, has good tissue compatibility, has no foreign body reaction, is easy for patients to accept, has good support, and can prevent chest wall floating and abnormal breathing; "can be placed in the body for a long time without loosening ; and can see through X-rays and other advantages, but the disadvantages are limited materials, insufficient tensile strength, and damage to other tissue structures to cause surgical trauma. Therefore, it is mostly used for small-area defect repair and flap packing and transfer. In addition, it can also be combined with artificial The most commonly used materials are pectoralis major, pectoralis major island flap, breast, rectus abdominis, rectus abdominis myocutaneous flap (TRAM), latissimus dorsi, latissimus dorsi myocutaneous flap, serratus anterior Muscle, diaphragm, omentum, autogenous ribs, iliotibial band, etc. The success of bone grafting largely depends on the quality of autologous bone, the blood supply of the bone graft bed and the soft tissue coverage with rich blood supply

In addition, there must be enough fixation to eliminate the scissors between the soft tissue and the bone graft, which is conducive to the growth of new blood vessels. The operation is demanding and difficult.

Moreover, the repair of autologous tissue tends to cover the defect site, and the rigidity condition is not ideal.

For a large area of ​​defect, autologous tissue repair is slightly insufficient, and surgical materials also increase the pain of the patient

[0005] 2. Artificial materials. There are many kinds. In the early days, there were mainly steel plates, titanium plates, plexiglass plates, steel wire mesh, etc., but the histocompatibility of these materials is poor, it is difficult to fix and loose, and it is not easy to shape and cut. Metal materials especially Metal plates will affect postoperative X-ray examination and radiotherapy, so they have been abandoned in recent years. At present, bone cement and / or autologous tissue materials are often used in bony chest wall repair in the world. This kind of material has good histocompatibility, and cutting It is convenient in shape, easy to sterilize, and does not affect postoperative X-ray examination and radiotherapy, but it still has poor flexibility, poor adhesion to tissues, insufficient tensile strength, and small size, which is limited in the repair of large-area defects. Disadvantages such as expensive

However, MMA has a strong exothermic reaction during shaping, and it is easy to burn the surrounding tissue. In addition, the filling material and the adjacent lung tissue can undergo anion exchange, and the patient may suffer from metabolic acidosis.

[0006] 3. Most of the biological materials are obtained from animal tissues. For example, Ya Naiquan et al. used self-made bovine pericardium slices + steel mesh to repair 9 cases of chest wall defects with satisfactory results. Pigs were also used as tissue materials. In general, the flexibility of biological materials Good, wide range of sources, strong tensile strength, not easy to age, easy to prepare and store. The disadvantage is that it is antigenic and easy to produce rejection. If it is not modified, the tensile strength will not be enough

Images