Modular seating for paralytic scoliosis: design and initial experience.

The conventional wheelchair sling seat provides little or no support to the spine of a child with myopathy or neurogenic muscular weakness. As the spinal muscles become weaker scoliosis may develop with associated deformity, pain and restriction of cardio-respiratory function. If muscle weakness is severe, the resultant fully developed deformity is virtually impossible to treat. Slowing the rate of increase of the deformity is, therefore, the most hopeful avenue of attack. This work addresses the hypothesis that custom moulded seating can increase sitting comfort and slow the rate of progression of spinal curvature in children with paralytic scoliosis, and further, that a range of standard or modular seats can achieve these goals at less cost. Previous work on this problem has ranged from simply padding the armrest, in order to distribute force over the rib cage, through to custom moulded seating. Our initial experience with custom moulding, using the bean bag evacuation and consolidation technique, produced several comfortable seats although the technique was labour intensive and therefore costly. This led us to attempt to develop a method of providing comfortable seating that would help control spinal deformity at reasonable cost. This paper describes the design of a standardized seating system for school age children with myopathy or neurogenic muscular weakness. Preliminary results indicate that this technique may have advantages over alternative methods of treatment. The radiological study is continuing.