Spinal alignment, surgery, and outcomes in cervical deformity: A practical guide to aid the spine surgeon

Compared to the thoracolumbar spine, the literature on cervical spine alignment is scarce. While a consistent number of articles have been published, few analyze the ideal surgical approaches for each type of deformity and the optimal amount of correction to achieve. This paper provides a comprehensive review of current literature on cervical spinal deformities (with or without myelopathy) and their surgical management; it is our goal to create a framework on which surgical planning can be made. A general assessment of the actually utilized parameters and correlation between the cervical and thoracolumbar spine alignment is presented. Moreover, we provide an analysis of cervical surgical approaches (anterior, posterior, or combined), techniques (laminoplasty, laminectomy and fusion, anterior cervical discectomy and fusion, corpectomy), and their indications. Finally, a complete evaluation of outcomes and postoperative health-related quality of life (HRQOL) measures based on questionnaires (NDI, VAS, SF-36, mJOA) is discussed. Several prospective studies would be useful in understanding how cervical alignment may be important in the assessment and treatment of cervical deformities with or without myelopathy. In particular, future works should concentrate on the correlation between cervical alignment parameters, disability scores, and myelopathy outcomes. We propose, via comprehensive literature review, a guide of practical key points on surgical techniques, cervical alignment, and symptom improvement goals surgeons should aim to achieve for each patient.