Cervical Spine and Cervicothoracic Junction—Anterior Approach

Goals of Surgery

For patients with mild myelopathy, a trial of nonoperative management may be considered, but patient counseling regarding symptom progression and risk of spinal cord injury is advised. ^, For patients with moderate to severe myelopathy, surgical management should be pursued. For patients with cervical radiculopathy, initial nonoperative treatment, including nonsteroidal antiinflammatory medication, physical therapy, and epidural steroid injection, can be considered. However, there is limited evidence for the long-term benefit of these nonoperative management options. ^, For patients with neurological deficit or failure of medical treatment, surgical management is recommended. The goal of surgical intervention, for both myelopathy and radiculopathy, is to eliminate ongoing neural compression to facilitate the resolution of symptoms and prevent progressive deterioration.

Surgical Consideration

Once a patient is deemed a surgical candidate from cervical spine degenerative disease, there are two main surgical approaches available: anterior and posterior approaches. ^, Although the ongoing debate between the relative effectiveness of an anterior versus a posterior approach remains undecided, there are clinical and radiographic indications that can guide treatment planning ( Table 109.2 ).

Two common surgical techniques employed via the anterior approach are anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF). For a single-level pathology located at the level of the intervertebral disc, ACDF is the standard treatment for most surgeons. In cases with retrovertebral compression (i.e., migrated herniated disc, the segmental subtype of ossification of the posterior longitudinal ligament [OPLL]), ACCF allow access for direct decompression. For multilevel disease, the options for surgical technique expand further, with multiple ACDFs, ACCF, and hybrid approaches ( Fig. 109.2 ). Extensive research has compared the radiographic and clinical outcomes of these surgical techniques, with mixed findings. Although proponents of multiple ACDFs highlight greater cervical lordosis and less operative blood loss, others have noted concerns of psuedoarthosis from the greater number of bone–graft interfaces involved in the fusion. Lastly, a hybrid model (ACDF + ACCF) may provide biomechanical advantages over multiple corpectomy by providing a higher degree of rigidity in flexion/extension and lateral bending while having similar advantages as multiple ACDFs. ^, However, all three decompression techniques have been shown to provide good clinical outcomes.

For patients undergoing anterior cervical spine surgery, other important preoperative considerations include a history of diabetes mellitus, corticosteroid use, and smoking. These comorbidities are correlated with a higher rate of postoperative complications, pseudarthrosis, and revision surgery. History of dysphagia or dysphasia should be assessed, with a low threshold for evaluation by otolaryngology. In particular, in the setting of prior neck surgery, subclinical vocal cord dysfunction may be present that will dictate the appropriate side to use for the surgical approach.

Surgical Considerations

Surgical planning in cases of spine tumor require careful evaluation of numerous factors, including patient’s neurological and health status, oncological staging, surgical staging, mechanical stability, and treatment intent (palliative vs. curative).

Numerous classifications have been developed for spine tumors, such as the Enneking staging system, Tomita’s scoring system, and the Weinstein–Boriani–Biagini (WBB) staging system. The WBB staging system is a validated framework that is useful for evaluating the feasibility of operative treatment and for surgical planning for primary spinal tumors. The WBB staging system classifies tumors based on 12 radiating zones and five concentric layers to design a strategy for surgical resection that does not injure vital neurovascular structures. This system is particularly useful when considering the feasibility of an en bloc resection.

The Neurologic, Oncologic, Mechanical, and Systemic (NOMS) framework is a guideline to surgical planning in cases of metastatic tumors. The NOMS framework consists of four variables, including neurological status (myelopathy, radiculopathy, extent of epidural compression), oncology (radiosensitivity of specific tumors), mechanical stability of the spine (Spinal Instability Neoplastic Score [SINS]), and the systemic status of the patient (comorbidities, tumor burden, prognosis). As part of the NOMS framework, the SINS is a validated tool used to evaluate spinal stability. Lastly, the Global Spine Tumour Study Group classification organizes operative strategies for metastatic tumor resection into vertebrectomy, debulking, and palliative decompression. The three strategies are further divided based on surgical technique (i.e., en bloc vs. piecemeal) and oncological margin (i.e., wide vs. intralesional).

Goals of Surgery

The goals of surgical intervention for spinal infection are to: (1) establish a microbiological diagnosis, (2) debride the involved tissue, (3) decompress the neural elements, (4) restore normal spinal alignment, (5) establish spinal stability, and (6) improve pain control.

Surgical Considerations

One of the ongoing challenges in managing spinal infection is delay in diagnosis because of the predominance of nonspecific symptoms such as neck and back pain. For infections located in the cervical spine, especially for spinal epidural abscess (SEA), such delays may impact long-term neurological prognosis. Suppiah et al. highlighted a significant difference in neurological recovery in patients based on early (<24–74 hours) versus delayed (>24–74 hours) surgery for SEA in their systematic review. Once a patient is deemed a surgical candidate, an important consideration for surgical planning is the involvement of the vertebral body and the resultant spinal alignment and stability. For pyogenic osteomyelitis, including Pott disease, an extensive lytic process in the vertebral body can lead to mechanical pain and progressive deformity. In such cases, surgical intervention yields a faster rate of neurological recovery compared with nonoperative management. Unlike in the thoracolumbar spine, an anterior approach or a combined anterior-posterior approach has been used most commonly for the cervical spine. Lastly, the choice of anterior column reconstruction technique in the setting of osteomyelitis continues to evolve with the growing popularity of titanium mesh cages (TMCs) and anterior cervical plating. The rates of hardware failure and wound complication in recent studies were found to be low and comparable to elective cervical spine procedures for degenerative conditions.