Polyaxial screws are commonly used in spinal surgery, particularly for spinal fusion procedures. Here are some key points about them:
- Design and Function: A polyaxial screw has a spherical head enclosed in a housing, allowing it to move along several different axes. This design provides flexibility in placing the screws and connecting them to rods.
- Applications: These screws are typically used to connect vertebrae to rods, stabilizing the spine. They are particularly useful in treating conditions like spinal fractures, scoliosis, and degenerative disc disease.
- Advantages: The flexibility of polyaxial screws makes them easier to place compared to monoaxial screws, which are fixed in one direction. This can lead to better alignment and stabilization of the spine.
- Safety: Polyaxial screws are designed to fail at the housing/screw interface before breaking in the shaft of the bone screw or the orthopedic rod, potentially adding a safety benefit.
- Clinical Outcomes: Studies have shown that polyaxial screws can achieve good radiological outcomes and maintain correction over time, making them effective for various spinal conditions.