Does axial cervical pain improve with surgical fusion? A meta-analysis
Authors: Harrop James S. , Gonzalez Glenn A. , Qasba Reyan K. , Porto Guilherme , Wainwright John V. , Thalheimer Sara , Schorsch Merrie , Vaccaro Alexander R. , Ghogawala Zoher 
Published: May 2023

OBJECTIVE
Axial neck pain is a prevalent condition that causes significant morbidity and productivity loss. This study aimed to review the current literature and define the impact of surgical intervention on the management of cervical axial neck pain.

METHODS
A search was conducted of three databases (Ovid MEDLINE, Embase, and Cochrane) for randomized controlled trials and cohort studies written in the English language with a minimum 6-month follow-up. The analysis was limited to patients with axial neck pain/cervical radiculopathy and preoperative/postoperative Neck Disability Index (NDI) and visual analog scale (VAS) scores. Literature reviews, meta-analyses, systematic reviews, surveys, and case studies were excluded. Two patient groups were analyzed: the arm pain predominant (pAP) cohort and the neck pain predominant (pNP) cohort. The pAP cohort had preoperative VAS neck scores that were lower than the arm scores, whereas the pNP cohort was defined as having preoperative VAS neck scores higher than the arm scores. A 30% reduction in patient-reported outcome measure (PROM) scores from the baseline represented the minimal clinically important difference (MCID).

RESULTS
Five studies met the inclusion criteria, involving a total of 5221 patients. Patients with pAP showed a slightly higher percent reduction in PROM scores from baseline than those with pNP. The NDI reduction in patients with pNP was 41.35% (mean change in NDI score 16.3/mean baseline NDI score 39.42) (p < 0.0001), whereas those with pAP had a reduction of 45.12% (15.86/35.15) (p < 0.0001). Surgical improvement was slightly but similarly greater in pNP patients compared with pAP patients (16.3 vs 15.86 points, respectively; p = 0.3193). Regarding VAS scores, patients with pNP had a greater reduction in neck pain, with a change from baseline of 53.4% (3.60/6.74, p < 0.0001), whereas those with pAP had a change from baseline of 50.3% (2.46/4.89, p < 0.0001). The difference in VAS scores for neck pain improvement was significant (3.6 vs 2.46, p < 0.0134). Similarly, patients with pNP had a 43.6% (1.96/4.5) improvement in VAS scores for arm pain (p < 0.0001), whereas those with pAP had 66.12% (4.43/6.7) improvement (p < 0.0001). The VAS scores for arm pain were significantly greater in patients with pAP (4.43 vs 1.96 points, respectively; p < 0.0051).

CONCLUSIONS
Overall, despite significant variations in the existing literature, there is mounting evidence that surgical intervention can lead to clinically meaningful improvements in patients with primary axial neck pain. The studies suggest that patients with pNP tend to have better improvement in neck pain than in arm pain. In both groups, the average improvements exceeded the MCID values and reached substantial clinical benefit in all studies. Further research is necessary to identify which patients and underlying pathologies will benefit most from surgical intervention for axial neck pain because it is a multifaceted condition with many causes.