Risk Factors for Prevertebral Soft Tissue Swelling Following Single-Level Anterior Cervical Spine Surgery

Abstract

Objective: Anterior cervical spine surgery (ACSS) is a common surgical procedure used to treat cervical spinal degenerative diseases. One of the complications associated with ACSS is prevertebral soft tissue swelling (PSTS), which can result in airway obstruction, dysphagia, and other adverse outcomes. This study aims to investigate the correlation between various cervical sagittal parameters and PSTS following single-level ACSS, as well as to identify independent risk factors for PSTS.

Methods: A retrospective study conducted at a single institution. The study population included all patients who underwent single-level ACSS between January 2014 and December 2022. Patients with a history of cervical spine surgery or trauma were excluded from the study. The presence and severity of PSTS was assessed by reviewing pre- and postoperative imaging studies. The potential risk factors for PSTS that were examined include patient age, sex, body mass index, tobacco use, comorbidities, serum albumin levels, operative time, implant type, implanted level, and various cervical spine sagittal parameters. Multivariate linear regression analysis was performed to identify the independent risk factors for PSTS.

Results: A total of 62 consecutive patients who underwent single-level ACSS over a 8-year period at a single institution were enrolled in this study. Only preoperative segmental angle showed positive correlation with PSTS among various cervical spine sagittal parameters (r=0.36, p=0.005). Artificial disc replacement showed a negative correlation with PSTS (β=-0.38, p=0.002), whereas the use of demineralized bone matrix (DBM) had a positive impact on PSTS (β=0.33, p=0.009). We found that male sex, lower preoperative serum albumin, and implantation of upper cervical level (above C5) were independent predictors for PSTS after single-level ACSS (β=1.21; 95% confidence interval [CI], 0.27 to 2.15; p=0.012; β=-1.63; 95% CI, -2.91 to -0.34; p=0.014; β=1.44; 95% CI, 0.38 to 2.49; p=0.008, respectively).

Conclusion: Our study identified male sex, lower preoperative serum albumin levels, and upper cervical level involvement as independent risk factors for PSTS after single-level ACSS. These findings can help clinicians monitor high-risk patients and take preventive measures to reduce complications. Further research with larger sample sizes and prospective designs is needed to validate these findings.

Keywords: Cervical spine; Postoperative complications; Risk factors; Soft tissue swelling.

Fig. 1.

The anteroposterior thickness of the prevertebral soft tissue was measured between the midpoint of the vertebral body’s anterior surface and the border of the airway shadow, as indicated by the arrow. A : Preoperative. B : Post-operative.

Fig. 2.

The O-C2 angle (O-C2A), the angle between McRae line and tangent line of axis’s inferior aspect; the C2-C7 angle (C2-7A), the angle between inferior aspects of axis and C7; the T1 slope, the angle between a horizontal line and the upper end plate of the T1 vertebra; the cervical sagittal vertical axis (cSVA), the distance between the horizontal offsets of the midpoints of C2 and C7; the segmental angle, the Cobb angle between the upper endplate of the upper vertebral body and the lower endplate of the lower vertebral body at the surgical level.

Fig. 3.

The illustration depicts the differences of mean prevertebral soft tissue swelling among each operative level.

Fig. 4.

The illustration depicts the differences of mean prevertebral soft tissue swelling among each operative method.