Trunk movement patterns and propulsion efficiency in wheelchair users with and without SCI

INTRODUCTION Handrim wheelchair propulsion is a mechanically inefficient mode of locomotion in comparison to arm cranking and cycling (de Groot et al., 2002). In addition, wheelchair propulsion has been associated with high physical strain and repetitive strain injuries (Janssen et al., 1994). The inefficiency of wheelchair propulsion has been attributed to factors such as, improper fit of the user to the wheelchair, decreased strength and poor technique. A recent study found that during propulsion, individuals with paraplegia exhibited paradoxical trunk movements; that is, the trunk moved in the opposite direction of the arms during force production (Rice et al., 2004). The authors suggested that this might be a result of impaired trunk stability due to paralysis of the back and abdominal core muscles. Thus, lack of trunk control may also be associated with lower mechanical efficiency (ME). The purpose of this study was to examine paradoxical trunk movements and ME during two speeds of wheelchair propulsion in two groups of individuals; a group with paraplegia and a group of unimpaired individuals. We hypothesized that the group without paraplegia would be more efficient at propelling a wheelchair despite their lack of experience and training.