Anterior Surgical Approach to the Cervical Spine

History

Although the surgical indications for anterior cervical procedures are discussed in later chapters, the history that is pertinent to the approach is any previous history of anterior neck surgery. Included are previous carotid artery surgery and thyroid surgery because both have also been reported to damage the innervation of the vocal cords. If patients present with any history of anterior surgery or have any concern about vocal cord paralysis, preoperative direct or indirect laryngoscopy should be performed by an otolaryngologist. Because of adjacent segment degeneration in the cervical spine, vocal cord paralysis is unfortunately not an uncommon occurrence, and preoperative planning is a must. Additional history that is relevant to the approach includes the diagnosis of a carotid bruit or carotid artery stenosis. It is reasonable to approach a side away from the carotid artery stenosis or bruit, out of concern for causing a stroke.

Physical Examination

When a patient is evaluated for anterior cervical surgery, the most important aspect of the physical examination is the presence or absence of neck extension with or without pain. This feature guides the options for intubation and intraoperative neck extension. Additional findings that should be considered are previous incisions and their anatomic locations near the planned surgical procedure.

Imaging

Preoperative imaging is important for obtaining the correct diagnosis, but it is also relevant to the approach. The course of the vertebral artery should be thoroughly evaluated on preoperative magnetic resonance imaging, to ensure that this vessel does not have an aberrant course. The vertebral artery can course through the vertebral body or disk or anterior to it instead of maintaining its normal location through the foramen transversarium. If the vertebral artery traverses the anterior aspect of the vertebral body or disk, it is at risk with the approach, and therefore, surgical dissection must proceed with caution. Additionally, if this artery courses through the vertebral body or disk, corpectomy and diskectomy may be contraindicated.

Indications and Contraindications

The relative contraindications to anterior cervical approaches are a previous history of cervical radiation, radical neck dissection or excision, and esophageal surgery. An anterior cervical approach has no absolute contraindications, but any history of the foregoing procedures makes the approach more challenging and higher risk.

Left-Sided Versus Right-Sided Approach

Currently, no conclusive evidence demonstrates improved outcomes or reduced complication rates with either a left-sided or a right-sided cervical approach. Proponents of the left-sided approach argue that the recurrent laryngeal nerve has a more predictable course within the tracheoesophageal groove and is at less risk, although the evidence in the literature to support this view is limited. Proponents of the right-sided approach state that it is more comfortable for the right-handed surgeon, avoids the thoracic duct, and has less risk to the esophagus (which is slightly more to the left).

Ultimately, no difference exists, and the approach side is surgeon specific unless the patient has any previous history of neck surgery. If a patient had previous neck surgery and the vocal cords are functioning normally (as confirmed by indirect laryngoscopy), then the approach should be from the contralateral side. Conversely, if the vocal cords are not functioning normally on the side of a previous approach, then the approach should be from the same side as before, to avoid damage to the one remaining normal vocal cord.