The manubrium as an external guide for centralizing anterior cervical plates: technique tips and initial experience

Area of Science:

• Spine surgery
• Orthopedic biomechanics
• Surgical technique innovation

Background:

• Accurate cervical plate alignment is crucial for optimal screw placement and biomechanical performance.
• Obesity and difficult surgical exposure can hinder reliable plate centralization during anterior cervical surgery.
• Existing methods may be limited by patient body habitus and landmark visibility.

Purpose of the Study:

• To introduce and validate a technique for centralizing cervical plates using external anatomical landmarks.
• To utilize the manubrium and mandible as guides for establishing a reliable midline axis for cervical plate placement.
• To assess the accuracy and reproducibility of this novel technique in anterior cervical surgery.

Main Methods:

• A technique using the manubrium's center as a primary guide and its alignment with the mandible's center as a secondary guide was described.
• Anteroposterior fluoroscopy was employed to confirm the midline axis bisected the cervical spine's spinous processes and vertebral bodies.
• Prospective data from 39 patients undergoing anterior cervical discectomy and fusion with cervical plates were collected.

Main Results:

• The technique demonstrated minimal mean angulation (2.24°) and translation (1.04 mm) of cervical plates.
• No significant differences in alignment were observed across 1-level, 2-level, and 3-level fusions (P > 0.05).
• High intraobserver reliability (R = 0.90) was achieved for the measurement technique.

Conclusions:

• The study validated that a line from the manubrium's midline to the mandible's midline accurately represents the cervical spine's midline.
• Prospective application of this technique resulted in consistently centered cervical plates across different fusion levels.
• This method provides a reliable benchmark for assessing cervical plate alignment in anterior cervical spine surgery.