Polyaxial screw

From WikiMD's Wellness Encyclopedia

Polyaxial screw is a type of orthopedic screw used in spinal surgery to secure implants to the vertebrae. It is called "polyaxial" because the head of the screw can rotate in multiple axes, allowing for greater flexibility in attaching the screw to the implant.

Design and Function[edit | edit source]

The polyaxial screw consists of two main parts: the screw body and the screw head. The screw body is threaded and is inserted into the bone. The screw head is designed to rotate in multiple axes, hence the term "polyaxial". This design allows the surgeon to adjust the angle of the screw head to align with the implant, making it easier to secure the implant to the bone.

The polyaxial screw is typically made of titanium, a strong and lightweight metal that is biocompatible, meaning it is safe to use in the body. The screw is also often coated with a material to promote bone growth and help secure the screw in place.

Applications[edit | edit source]

Polyaxial screws are primarily used in spinal surgery, particularly in procedures to correct spinal deformities such as scoliosis and kyphosis. They are also used in spinal fusion surgery, a procedure in which two or more vertebrae are fused together to stabilize the spine and relieve pain.

In these procedures, the polyaxial screws are inserted into the vertebrae and then attached to a rod or plate that is used to stabilize the spine. The ability of the screw head to rotate in multiple axes allows the surgeon to adjust the position of the screw to best fit the anatomy of the patient's spine.

Advantages and Disadvantages[edit | edit source]

The main advantage of polyaxial screws is their flexibility. The ability of the screw head to rotate in multiple axes allows the surgeon to adjust the position of the screw to best fit the anatomy of the patient's spine. This can make the surgery less invasive and reduce the risk of complications.

However, polyaxial screws also have some disadvantages. They can be more difficult to insert than other types of screws, and there is a risk that the screw head could loosen over time. In addition, while the polyaxial design allows for greater flexibility, it also means that the screw is not as stable as a monaxial screw, which could potentially lead to instability in the spine.

See Also[edit | edit source]

Polyaxial screw Resources
Wikipedia
WikiMD
Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD

Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD

WikiMD's Wellness Encyclopedia

Let Food Be Thy Medicine
Medicine Thy Food - Hippocrates

Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.

Contributors: Prab R. Tumpati, MD