A number of orthoses have been designed to restore stance and walking
in paraplegic subjects. Among them, the reciprocating gait orthosis (R
GO) appears to be one which is most widely adopted. The great energeti
c cost of orthotically aided walking is the main factor limiting the w
alking capability of paraplegic subjects. The purpose of the present r
esearch was to give a complete biomechanical evaluation of RGO locomot
ion in order to provide data that can be used for further improvements
of the orthosis. From the whole body kinematics the mechanical work d
one to move the orthosis was estimated; by measuring the actual metabo
lic cost of RGO locomotion the efficiency was evaluated as the ratio b
etween mechanical work and energy expenditure. It is found that RGO lo
comotion is a very demanding task in terms both of energy expenditure
and of the mechanical work required. Furthermore, it is evident that t
he major determinant of this poor efficiency of RGO locomotion is the
enormous amount of work required to move the orthosis which, in turn,
reflects its poor mechanical characteristics. To accomplish the demand
of real mobility, devices for transferring work from the upper to the
lower portion of the body must be substantially improved. This techni
cal aspect must be parelleled by suitable training programmes especial
ly designed to improve the aerobic power of paraplegic subjects and th
eir body composition (ie less fat and more muscle).