LATERAL MASS SCREW
Lateral mass screws are orthopedic implants used in spinal fusion surgeries, particularly in the cervical spine. Here's an overview of their specifications and uses:
Specification
- Material: Lateral mass screws are typically made from medical-grade titanium or titanium alloy. This material is chosen for its biocompatibility, strength, and compatibility with bone tissue. Some screws may also be made from stainless steel.
- Design: Lateral mass screws have a screw-like design with a threaded shaft and a head. The head of the screw may be round, cylindrical, or tapered, and it typically features a recess or saddle to accommodate the rod in spinal instrumentation systems. The threads on the shaft provide secure fixation within the lateral mass of the vertebra.
- Size: Lateral mass screws come in various sizes to accommodate different patient anatomies and surgical requirements. The size of the screw is selected based on factors such as the size of the lateral mass, the level of the spine being instrumented, and the surgical technique being employed.
- Thread Pattern: The thread pattern of lateral mass screws may vary depending on the manufacturer and design. Common thread patterns include cortical threads, cancellous threads, or a combination of both, designed to optimize fixation within the bone.
- Length: Lateral mass screws are available in various lengths to accommodate the specific surgical technique and the anatomy of the cervical spine. Surgeons may select screws of appropriate length to ensure adequate engagement with the lateral mass while avoiding injury to adjacent neurovascular structures.
Uses
- Spinal Fusion Surgery: Lateral mass screws are primarily used in spinal fusion surgeries of the cervical spine. They provide stabilization and instrumentation of the cervical vertebrae, facilitating fusion of the adjacent vertebral segments. Lateral mass screws are commonly used in conjunction with rods and other spinal instrumentation components to construct a rigid framework that promotes fusion.
- Treatment of Cervical Instability: Lateral mass screws are used to treat cervical instability resulting from degenerative conditions, trauma, or deformities such as cervical spondylosis, cervical spondylolisthesis, or cervical spine fractures. By providing stable fixation within the lateral masses of the cervical vertebrae, these screws help restore spinal alignment and stability.
- Correction of Cervical Deformities: Lateral mass screws may be employed in the correction of cervical deformities such as cervical kyphosis or cervical scoliosis. They are used in conjunction with corrective osteotomies and spinal realignment procedures to achieve optimal spinal alignment and curvature correction.
- Revision Surgery: Lateral mass screws may be used in revision cervical spine surgeries to augment or replace existing instrumentation. They can provide additional stability and support in cases where previous instrumentation has failed or requires modification.
- Minimally Invasive Surgery: In minimally invasive cervical spine surgeries, lateral mass screws with a low-profile design are used to minimize tissue disruption and facilitate less invasive approaches. They allow for stabilization of the cervical spine while preserving adjacent anatomical structures.
In summary, lateral mass screws are valuable instruments in cervical spine surgery, offering reliable fixation and stabilization of the cervical vertebrae. They are utilized by trained spinal surgeons following proper surgical techniques and patient-specific considerations to achieve successful surgical outcomes.