The Influence of Radiographic Severity on the Relationship between Muscle Strength and Joint Loading in Obese Knee Osteoarthritis Patients

Table 1

Characteristics of obese medial knee OA patients.

	All	Less severe	Severe
	𝑁=136	𝑁=73	𝑁=63
Gender
Females no. (%)	112 (81%)	63 (86%)	49 (78%)
Males no. (%)	24 (19%)	10 (14%)	14 (22%)
Age (years)	63.0 ± 6.5	62.3 ± 5.9	63.6 ± 7.0
	(61.9 to 64.1)	(61.0 to 63.8)	(61.9 to 65.4)
Height (m)	1.66 ± 0.08	1.65 ± 0.07	1.67 ± 0.10
	(1.65 to 1.68)	(1.64 to 1.67)	(1.65 to 1.69)
Body mass (kg)	101.7 ± 13.8	99.7 ± 12.6	104.0 ± 14.8
	(99.3 to 104.1)	(96.5 to 102.5)	(100.5 to 107.9)
BMI (kg/m^2)	36.8 ± 4.1	36.4 ± 3.9	37.3 ± 4.2
	(36.1 to 37.5)	(35.4 to 37.3)	(36.3 to 38.4)
Self-selected walking speed (m/s)	1.09 ± 0.19	1.11 ± 0.18	1.06 ± 0.20
	(1.06 to 1.12)	(1.07 to 1.15)	(1.01;1.11)
Alignment (degrees, positive is varus)	6.5 ± 4.7	4.3 ± 3.4	9.0 ± 4.7
	(5.7 to 7.3)	(3.5 to 5.1)	(7.8 to 10.2)
Peak KAM (%BW*HT)	3.17 ± 1.04	2.88 ± 0.95	3.51 ± 1.05
	(3.00 to 3.35)	(2.66 to 3.10)	(3.25 to 3.77)
Peak isometric extensor torque (Nm/kg)	1.14 ± 0.43	1.15 ± 0.46	1.12 ± 0.38
	(1.07 to 1.21)	(1.04 to 1.26)	(1.03 to 1.22)
Peak isometric flexor torque (Nm/kg)	0.54 ± 0.17	0.53 ± 0.16	0.54 ± 0.18
	(0.51 to 0.56)	(0.49 to 0.57)	(0.50 to 0.59)
Pain (0–100 score, lower is worse)	44.3 ± 20.0	42.7 ± 20.8	46.1 ± 19.1
	(40.9 to 47.7)	(37.8 to 47.5)	(41.3 to 50.9)
Medial KL grade (scale 0–4)	2.5 ± 1.0	1.7 ± 0.5	3.4 ± 0.5
	(2.3 to 2.6)	(1.6 to 1.8)	(3.2 to 3.5)
Lateral KL grade (scale 0–4)	1.5 ± 0.7	1.0 ± 0.6	1.9 ± 0.4
	(1.3 to 1.6)	(0.9 to 1.2)	(1.8 to 2.0)
Patella femoral KL grade (scale 0–4)	2.0 ± 0.9	1.7 ± 0.9	2.4 ± 0.8
	(1.9 to 2.2)	(1.5 to 1.9)	(2.2 to 2.6)

Results are given in mean ± SD (95% confidence interval) if not stated otherwise. KAM: external knee adduction moment, Nm=newton×meter, BW: body weight, HT: height, and KL: Kellgren and Lawrence.