Bone screw

Abstract

The invention discloses a bone screw, which comprises a thread part comprising a first front surface (11), a first rear surface (12) and a first thread on the tooth top; moreover, a second thread comprising a second front surface (16) and a second rear surface (17) is formed on at least partial tooth top of the first thread. Due to the presence of the second thread, the contact area of the screw and bones and the axial pullout force bearing area are obviously increased, and the bending resistance is not obviously influenced; therefore, the mechanical properties of the screw are comprehensively improved.

Description

technical field [0001] The invention relates to a bone screw with improved mechanics and mechanical properties, which is suitable for the connection of broken bones and the correction of bone lesions and deformities in cervical vertebrae, spine, cranium and other parts. Background technique [0002] In orthopedic surgery, bone screws are often used to connect broken bones or correct various bone lesions and deformities. Since the bone is the main force-bearing structure of the human body to bear various mechanical loads, and the connected broken bone or the repaired bone can easily transfer the force load to the bone screw used for fixation, so in actual use , Bone screws often need to withstand a variety of periodic and different variable forces. This not only requires that the bone screw itself is particularly strong and will not be damaged under the action of external force, but also requires that it can be firmly bonded to the bone tissue so that it will not be dislodge...

AI Technical Summary

Problems solved by technology

However, doing so can adversely affect other mechanical properties of the bone screw

[0005] For example, in terms of the bending strength of the screw, the increase in the height of the thread profile will make the inner diameter of the thread relatively smaller, so that the cross-sectional area of ​​the screw that can withstand the bending stress is reduced, and the bending strength is significantly reduced.

Especially when the thread density is high, it is easy to form a sharp corner at the bottom of the tooth, which leads to stress concentration and further reduces the bending strength of the screw

Moreover, the height of the tooth form is too high and the axial dimension of the tooth form is too small, which will cause the fracture of the thread teeth

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