An increased response to experimental muscle pain is related to psychological status in women with chronic non-traumatic neck-shoulder pain

Table 1 Median and range values for clinical neck-shoulder pain intensity ratings, size of pain areas and different psychological instruments for the trapezius myalgia group (NSP) and for the controls (CON)

	NSP (n = 19) Median (range)	CON (n = 30) Median (range)	p-value
Clinical neck pain intensity (VAS mm)	69 (40-90)	0 (0-20)	<.001
Clinical shoulder pain intensity (VAS mm)	67 (19-88)	0 (0-3)	<.001
Pain duration (months)	120 (36-273)	NA
Current pain area size (mm²)	788 (150-3616)	NA
Worst pain area size (mm²)	1658 (433-4344)	NA
Least pain area size (mm²)	420 (13-1829)	NA
Awakening problems (KSQ-Aw)	2 (.3-3.3)	1 (0-2.7)	<.001
Sleep disturbances (KSQ-Dst)	2 (1-3.5)	1 (0-3.5)	<.001
Daytime sleepiness (KSQ-Sd)	1.4 (.2-2.6)	.6 (0-2.2)	<.001
Depression (HADS-D)	3 (1-13)	1 (0-5)	<.001
Anxiety (HADS-A)	4 (0-17)	2 (0-10)	.003
Anxiety sensitivity (ASI)	10 (1-33)	8 (2-35)	.225
Pain anxiety (PASS-20)	37 (17-70)	NA
Catastrophizing (PCS)	15 (6-29)	2 (0-21)	<.001
Fear-avoidance, physical activity (FABQphysical)	10 (4-17)	NA
Fear-avoidance, work (FABQwork)	22 (0-42)	NA
Pain disability (PDI)	25 (13-56)	NA

P-values for differences between groups were derived from Mann-Whitney U-tests. NA denotes not applicable.
Abbreviations: KSQ = Karolinska sleep questionnaire, KSQ-Aw = KSQ- subscale "awakening problems", KSQ-Dst = KSQ- subscale "daytime sleepiness", KSW-Sd = KSQ- subscale "sleep disturbances", HADS = hospital anxiety and depression scale; HADS-D = depression subscale of HADS, HADS-A = anxiety subscale of HADS, ASI = anxiety sensitivity index, PASS = pain anxiety symptoms scale, PCS = pain catastrophizing scale; FABQ = fear-avoidance beliefs questionnaire, FABQphysical = subscale fear-avoidance beliefs for physical activity of FABQ, FABQwork = subscale fear-avoidance beliefs for work of FABQ, PDI = pain disability index.