This study aimed to determine the age- and sex-specific incidence of cervical spondylotic myelopathy (CSM) and its associated risk of causing subsequent spinal cord injury (SCI).

Retrospective cohort. To describe the incidence of complications and mortality associated with surgery for degenerative disease of the cervical spine using population-based data. To evaluate the associations between complications and mortality and age, primary diagnosis and type of surgical procedure. Recent studies have shown an increase in the number of cervical spine surgeries performed for degenerative disease in the United States. However, the associations between complications and mortality and age, primary diagnosis and type of surgical procedure are not well described using population-based data. We created an algorithm defining degenerative cervical spine disease and associated complications using the International Classification of Diseases-ninth revision Clinical Modification codes. Using the Nationwide Inpatient Sample, we determined the primary diagnoses, surgical procedures, and associated in-hospital complications and mortality from 1992 to 2001. From 1992 to 2001, the Nationwide Inpatient Sample included an estimated 932,009 (0.3%) hospital discharges associated with cervical spine surgery for degenerative disease. The majority of admissions were for herniated disc (56%) and cervical spondylosis with myelopathy (19%). Complications and mortality were more common in the elderly, and after posterior fusions or surgical procedures associated with a primary diagnosis of cervical spondylosis with myelopathy. There are significant differences in outcome associated with age, primary diagnosis, and type of surgical procedure. Administrative databases may underestimate the incidence of complications, but these population-based studies may provide information for comparison with surgical case series and help evaluate rare or severe complications.

The optimal surgical approach for multilevel cervical spondylotic myelopathy (CSM) has not been defined, and the relative merits of multilevel anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy (2-level or skip 1-level corpectomy) and fusion (ACCF) remain controversial. However, few comparative studies have been conducted on these two surgical approaches. This study retrospectively reviewed the case histories of 120 patients that underwent surgical treatment for 3- or 4-level CSM from July 2003 to June 2008. One hundred and twenty patients (81 male and 39 female) of mean age 58.3±9.8 years (37-78) were included. The study compared perioperative parameters (blood loss, operation times), complications [surgery-related complications (CSF, hoarseness, epidural hematoma, C5-palsy, dysphagia), instrumentation and graft related complications (dislodgement, subsidence)], clinical parameters [Japanese Orthopedic Association (JOA) scores, Neck Dysfunciton Index (NDI) scores], and radiologic parameters (segmental lordosis, fusion rate). At a minimum of 2-year follow-up, both ACDF and ACCF groups demonstrated a significant increase in the JOA scores (preoperatively 9.25±1.9 and 8.86±1.9, postoperatively 13.86±1.6 and 13.27±1.8, respectively), segmental lordosis (preoperatively 9.79±3.4 and 9.54±3.0, postoperatively 17.75±2.6 and 14.49±2.5, respectively) and NDI scores (preoperatively 12.56±3.0 and 12.21±3.4, postoperatively 3.44±1.7 and 5.68±2.6, respectively). Six patients (2 dislodgement, 4 subsidence) in ACCF group had instrumentation and graft related-complications and they had no obvious neurological symptoms without a second operation. Blood loss (102.81±51.3 and 149.05±74, respectively, P=0.000), NDI scores (P=0.000), and instrumentation and graft related-complications (P=0.032) were significantly lower in the ACDF group, whereas operation time (138.07±30.9 and 125.08±26.4, respectively, P=0.021) and segmental lordosis (P=0.000) were significantly greater in the ACDF group. Other parameters were not significantly different in the two groups. Surgical managements of 3- or 4-level CSM by ACDF or ACCF showed no significant differences in terms of achieved clinical symptom improvements, with the exception of better postoperative NDI scores in ACDF. In addition, ACDF is better than ACCF in terms of blood loss, lordotic curvature improvement and instrumentation and graft related-complication rates, with the exception of operation times.