The purpose of this investigation was to determine whether force platform measurements can be used to objectively assess short-term effects of spinal manipulation on patients with diagnosed, chronic unilateral "sacroiliac dyskinesia," here defined as decreased interarticular mobility of the sacroiliac joint. Nine patients walked across a force platform, were than manipulated by a chiropractor and then repeated the gait trials. Temporal and kinetic gait variables from the force platform measurements were analyzed for changes in the symmetry of the subjects' gait before and after treatment sessions. There was a distinct tendency towards improved gait symmetry after treatment in those cases where the gait was asymmetric prior to the treatment. This result indicated that force platform measurements may be used successfully to assess the effects of spinal manipulations on the gait of patients with sacroiliac dyskinesia.