Table 2 Minimum (SD) joint space width (mm) in knees with no definite joint space narrowing in either the medial or lateral tibiofemoral compartment and in the narrowed compartment of knees with medial or lateral osteoarthritis.

JSN location	None	Medial	None	Lateral
Compartment JSW	Medial	Medial	Lateral	Lateral
Standing AP radiograph	4.33 (1.00), n = 73	2.40 (1.10), n = 95	4.99 (1.27), n = 73	3.36 (1.19), n = 33
Lyon schuss radiograph	3.94 (0.88), n = 38	1.61 (1.2), n = 96	5.32 (1.16), n = 38	1.44 (1.30), n = 64
p Value	0.045	<0.001	NS	<0.001

AP, anteroposterior; JSN, joint space narrowing; JSW, joint space width; NS, not significant.