Table 3

Patient-reported outcome measurements between VAS ANR groups.

PROM	Interval	NAPD (ANR ≤1.0) (n = 91)	APD (ANR >1.0) (n = 31)	Univariate Analysis, P Value		Multivariate Regression, β Coefficient (95% CI), P Value
PROM	Interval	NAPD (ANR ≤1.0) (n = 91)	APD (ANR >1.0) (n = 31)	Paired Samples t Test	Independent Samples t Test or χ² Analysis	Multivariate Regression, β Coefficient (95% CI), P Value
PCS-12	Preoperative	33.1 (31.6, 34.5)	33.6 (30.6, 36.5)	NAPD: <0.001^aAPD: <0.001^a	0.691	NAPD: -APD: 0.675 (−3.647, 4.998), 0.757
	Postoperative	40.0 (37.6, 42.4)	41.8 (37.5, 46.0)		0.412
	Delta	6.9 (4.8, 9.0)	7.7 (3.9, 11.6)		0.522
	RR	10.2%	10.7%	—	0.661
	% MCID	41.8%	51.6%	—	0.340
MCS-12	Preoperative	47.0 (44.4, 49.7)	46.0 (41.9, 50.2)	NAPD: 0.903APD: 0.031^a	0.615	NAPD: -APD: 4.179 (−0.466, 8.823), 0.077
	Postoperative	46.9 (44.5, 49.3)	52.1 (47.9, 56.3)		0.008^a
	Delta	−0.2 (−3.0, 2.7)	5.5 (−0.1, 11.0]		0.043^a
	RR	0.0%	0.1%	—	0.114
	% MCID	30.8%	48.4%	—	0.076
NDI	Preoperative	46.0 (42.0, 50.0)	42.0 (35.0, 48.0)	NAPD: <0.001^aAPD: <0.001^a	0.243	NAPD: -APD: −9.808 (−18.053, –1.563), 0.020^a
	Postoperative	31.9 (26.8, 37.0)	18.8 (12.2, 25.4)		0.011^a
	Delta	−13.9 (−18.0, –9.7)	−22.8 (−30.2, –15.4)		0.038^a
	RR	31.1%	51.7%	—	0.059
	% MCID	45.1%	61.3%	—	0.118
VAS neck	Preoperative	6.5 (6.0, 7.0)	5.6 (4.8, 6.5)	NAPD: <0.001^aAPD: 0.001^a	0.041^a	NAPD: -APD: −0.704 (−1.929, 0.552), 0.258
	Postoperative	3.8 (3.1, 4.4)	2.5 (1.6, 3.3)		0.076
	Delta	−2.8 (−3.4, –2.1)	−3.0 (−4.1, –1.8)		0.504
	RR	41.2%	42.1%	—	0.331
	% MCID	51.6%	54.8%	—	0.748
VAS arm	Preoperative	4.7 (4.1, 5.4)	7.0 (6.3, 7.7)	NAPD: <0.001^aAPD: <0.001^a	0.001^a	NAPD: -APD: −0.942 (−2.268, 0.384), 0.162
	Postoperative	3.3 (2.7, 4.0)	2.5 (1.5, 3.5)		0.264
	Delta	−1.4 (−2.2, –0.6)	−4.4 (−5.6, –3.2)		0.001^a
	RR	48.3%	57.4%	—	0.499
	% MCID	37.4%	61.3%	—	0.020^a

Note: Preoperative, postoperative, and delta data are presented as mean (95% CI). VAS ANR group outcomes compared with univariate analysis—paired samples t test, Kruskal-Wallis H testing with Dunn multiple pairwise comparisons conducted for post hoc analysis, or Pearson Χ ² analysis—and multivariate regression. RR were defined as: (delta outcome score/[optimal outcome score – observed outcome score]), where the following optimal outcome scores were used: 100 (PCS-12 and MCS-12) or 0 (NDI).² The percentage of patients reaching the % MCID was based on the following threshold values: PCS-12, 8.1 points; MCS-12, 4.7 points; and NDI, 15 points.^3,4 Multivariate regression analysis conducted using the neck pain dominant group as a baseline for comparison—controlling for age, sex, Body Mass Index, smoking status, (never, current, former), follow-up (months), and No. of levels fused.
aIndicates statistical significance (P < 0.05).
ANR, arm neck ratio; APD, arm pain dominant; MCID, minimum clinically important difference; MCS-12 , Mental Component Score of the Short Form-12 Survey; NAPD, non-arm pain dominant; NDI , Neck Disability Index ; PCS-12 , Physical Component Score of the Short Form-12 Survey; RR, recovery ratios; VAS, visual analog scale.