How does the Legend Fixation System screw thread design enhance the fixation effect in the lumbar intervertebral space?
Publish Time: 2024-11-05
The screw thread design in the Legend Fixation System plays a vital role in enhancing the fixation effect in the lumbar intervertebral space.
First, the shape of the thread is one of the key factors. The specially designed thread profile can increase the contact area with the vertebral bone. For example, the edges of the trapezoidal or serrated threads can better embed into the bone. The side of the trapezoidal thread is an inclined plane, which can gradually squeeze the surrounding bone during the screwing process into the vertebrae to form a tight fit. The serrated thread is similar, with its sharp tooth structure that can grip the bone like a hook. The advantage of this shape is that it can effectively resist the pull-out force of the screw in the vertical direction, thereby enhancing the stability of the fixation and ensuring that the screw can be firmly maintained in the intervertebral position under various force conditions in the patient's daily activities.
The pitch design of the thread also has a significant impact on the fixation effect. The appropriate pitch ensures that the screw exerts appropriate pressure on the bone when screwing in. If the pitch is too large, the continuity of the bone structure may be destroyed during the screwing process, affecting the fixation effect; if the pitch is too small, the screw is difficult to screw in and may not fully exert its fixation effect. Appropriate pitch allows each circle of thread to interact with the bone evenly, dispersing the tension of the screw to more bone areas, avoiding excessive local stress and causing bone damage, while ensuring sufficient fixation strength.
In addition, the depth of the thread is equally important. Deeper threads can penetrate deep into the vertebrae and increase the degree of engagement with the bone. In the complex force environment of the lumbar spine, such as torsion and bending, deep threads can better resist these forces, prevent the screw from loosening or shifting, and provide a stable mechanical environment for lumbar intervertebral fusion, which is beneficial to the patient's rehabilitation and long-term lumbar functional stability. In short, through the carefully designed thread shape, pitch and depth, the Legend Fixation System screws can significantly enhance the fixation effect in the lumbar intervertebral space.
