Long-segment posterior cervical decompression and fusion: does caudal level affect revision rate?

Abstract

OBJECTIVE Posterior cervical decompression and fusion (PCDF) is a commonly performed procedure to address cervical myelopathy. A significant number of these patients require revision surgery for adjacent-segment disease (ASD) or pseudarthrosis. Currently, there is no consensus among spine surgeons on the inclusion of proximal thoracic spine instrumentation. This study investigates the benefits of thoracic extension in long-segment cervical fusions and the potential drawbacks. The authors compare outcomes in long-segment subaxial cervical fusion for degenerative cervical myelopathy with caudal vertebral levels of C6, C7, and T1. METHODS A retrospective analysis identified 369 patients who underwent PCDF. Patients were grouped by caudal fusion level. Reoperation rates for ASD and pseudarthrosis, infection, and blood loss were examined. Data were analyzed with chi-square, 1-way ANOVA, and logistic regression. RESULTS The total reoperation rate for symptomatic pseudarthrosis or ASD was 4.8%. Reoperation rates, although not significant, were lower in the C3–6 group (2.6%, vs 8.3% for C3–7 and 3.8% for C3–T1; p = 0.129). Similarly, rates of infection were lower in the shorter-segment fusion without achieving statistical significance (2.6% for C3–6, vs 5.6% for C3–7 and 5.5% for C3–T1; p = 0.573). The mean blood loss was documented as 104, 125, and 224 mL for groups 1, 2, and 3, respectively (p < 0.001). CONCLUSIONS Given the lack of statistical difference in reoperation rates for long-segment cervical fusions ending at C6, C7, or T1, shorter fusions in high-risk surgical candidates or elderly patients may be performed without higher rates of reoperation.

Patient-Reported Outcomes Following Anterior and Posterior Surgical Approaches for Multilevel Cervical Myelopathy

“…A large database study of 16,033 patients receiving multilevel (>1 level) ACDF suggested a revision surgery rate of 10.7%. Reoperation rates for adjacent segment disease and pseudarthrosis after 3 or more levels of PCDF have been reported at 4.8% in a retrospective cohort of 369 patients 41. Conversely, in a recent large claims database, revision rates for 3-level PCDF were higher than ACDF (7.9% to 3.6%; P < 0.0001) 42.…”

Lateral Mass Screws Versus Pedicle Screws at C7 - Reoperation Rates for Adjacent Segment Disease (Operative ASD) and Nonunions (Operative Nonunions) in Posterior Cervical Fusions

“…They found that the rate of symptomatic ASD requiring surgery was 0.74 (4/539) in the LMS group versus 1.19 (1/84) in the CPS group without any statistical difference. In 2021, Hines et al26 reported on a combination of LMS and CPS used at C7. In their study, there were 108 patients with PCFs C3–7 that included 71 patients (65.7%) with LMS at C7 and 37 patients (34.3%) with PS at C7.…”

“…Several of the studies were comparative 11,27 with LMS and CPS at all cervical levels of the spine or noncomparative [21][22][23][24][25] with either all LMS screws or all CPS or a combination of both. 26…”

“…In our study, we found that an operative ASD incidence rate was 1.15% for LMS at C7 and 2.99% for CPS at C7. Again, although reoperations for nonunions with LMS or CPS at C7 in PCFs have been highlighted in a few studies, 11,[22][23][24][25][26][27] none have had a direct comparison. None of the studies have CPS only at C7, with LMS at other levels.…”

“…[18][19][20] How these biomechanical studies translate to clinical outcomes to the superiority of one technique over another (LMS vs. CPS) is still unclear, with limited studies comparing both techniques. 11,[21][22][23][24][25][26][27] Recent studies have shown no difference in reoperation rates for adjacent segment disease and for nonunions stopping posterior fusions at C7 versus crossing the cervical thoracic junction. [28][29][30] The corollary to this is: Does the type of screws used at C7 make a difference in outcomes?…”