Table 4.

Characteristics per shoulder pain trajectory measured at start of active rehabilitation (t₁) (N = 225) and significant differences between trajectories (described in n and % per trajectory)

	Descriptives		P values of differences between trajectories
	High pain (n = 63)	Decrease of pain (n = 14)	No or low pain (n = 148)	High pain vs. decrease of pain	High pain vs. no or low pain	Decrease of pain vs. no or low pain
Demographics
Male	44 (70%)	13 (93%)	111(74%)	0.067	0.270	0.114
Female	19 (30%)	1(7%)	37(26%)
Age (years)	40.4 (13.7)	32.6 (12.0)	41.7(14.4)	0.195	1.00	0.068
TSI (days)	107 (72)	100(40)	92(75)	0.516	0.086	0.033
Lesion characteristics
Paraplegia	21 (33%)	3 (21%)	110 (74%)	0.298	<0.001	<0.001
Tetraplegia	42 (67%)	11 (79%)	38 (26%)
Complete	45 (71%)	11 (79%)	96 (65%)	0.430	0.283	0.267
Incomplete	18 (29%)	3 (21%)	49 (35%)
Physical characteristics
Presence of shoulder pain before SCI	10 (16%)	2 (14%)	9 (6%)	0.287	<0.001	<0.001
Presence of obesity (BMI ≥ 22)	34 (50%)	2 (14%)	86 (58%)	0.012	0.219	0.002
Presence of limitation in shoulder ROM of >10°	41 (60%)	8 (57%)	31 (21%)	0.547	<0.001	0.004
MMT score (range 0–50)	36.6 (13.1)	33.3 (10.3)	45.4 (9.4)	0.011	<0.001	<0.001
Spasticity of elbow flexors or extensors score (range 0–3)	0.54 (1.18)	0.33 (0.65)	0.10 (0.47)	<0.001	<0.001	0.982

For sex, lesions level, completeness of SCI, the presence of shoulder pain before SCI, the presence of obesity, the presence of shoulder ROM limitation, the values are n (and %) per trajectory. For age, TSI, MMT, and spasticity, the mean (and SD) is described. All variables were measured at the start of active rehabilitation. Significance was set at P < 0.001.

TSI, time since injury; BMI, body mass index; ROM, range of motion; MMT, manual muscle testing.