Fig. 3.

Bar graphs showing the relief of pain during walking, standing and, sitting at 4–7 years postoperatively (all according to the subscales of ODI) Walking: A I cannot walk at all without increasing pain. B I cannot walk more than 1/4 mile without increasing pain. C I cannot walk more than 1/2 mile without increasing pain. D I cannot walk more than 1 mile without increasing pain. E I have some pain on walking but it does not increase with distance. F I have no pain on walking. Standing: A I avoid standing because it increases the pain immediately. B I cannot stand for longer than 10 min without increasing pain. C I cannot stand for longer than 0.5 h without increasing pain. D I cannot stand for longer than 1 h without increasing pain. E I have some pain on standing but it does not increase with time. F I can stand as long as I want without pain. Sitting: A I avoid sitting because it increases pain immediately. B Pain prevents me from sitting more than 10 min. C Pain prevents me from sitting more than 0.5 h. D Pain prevents me from sitting more than 1 h. E I can sit only in my favorite chair as long as I like. F I can sit in any chair as long as I like