“…Abnormalities in the paraspinal muscles have been implicated by several investigators as a possible causative factor in the production and progression of adolescent idiopathic scoliosis (Fidler et al, 1974;Fidler & Jowett, 1976;Ford et al, 1984;Spenser & Eccles, 1976;Yarom & Robin, 1979). An increased myoelectric response on the convex side of the curve, near its apex, was the main finding reported by various authors ( Alexander & Season, 1978;Butterworth & James, 1969;Guth & Abbink, 1980;Henssge, 1962;Redford et al, 1969;Spenser & Eccles, 1976;Wong et al, 1980;Yarom & Robin, 1979;Zetterberg et al, 1984), but not all agreed on the meaning of these findings. In early reports a fatigue mechanism was suggested (Riddle & Roaf, 1955), while others explained the difference as an effect of the stretching of the erector spinae muscles on the convex side (Butterworth & James, 1969).…”