Abstract
Objectives To examine the amplitude, latency, and bilateral symmetry of long loop postural reflexes after stroke.
Rationale: Computerized platform posturography is a new technique for assessing neural control of posture and balance. It may help quantify stroke-related neurologic impairments and measure their improvement over time.
ABS1:Methods: As part of an ongoing study of postural control after stroke, patients with normal EquiTest sensory analysis scores were randomly selected for study Their performance was compared with that of normal community volunteers. Postural control was assessed by preprogrammed anterior and posterior horizontal forceplate movements using an EquiTest dynamic posturography system five to eight weeks after an initial stroke. Subjects included 24 patients (13 males and 11 females) with acute stroke admitted to the Burke Rehabilitation Hospital. Patients had a mean age of 63.1 years, and the community controls had a mean age of 69.2 years.
Results: Postural control was severely disrupted in the paretic leg. Motor control results were abnormal in 75 percent of the patients after stroke (18 of 24) when compared with the controls. Significant differences in the latencies and amplitude of long loop postural reflexes were seen between the affected and nonaffected leg in the same patient during movement forward (p < 0.005) and backward (p < 0.005) and response strength (p < 0.005). The nonaffected leg had normal reflex latencies while the response latencies in the affected leg were either absent or slowed and of decreased amplitude.
Conclusion: With posturographic assessment, the amplitude, latency, and bilateral symmetry of long loop postural reflex latencies are abnormal in hemiparetic patients. These reflexes may be useful in the study of the mechanism of gait and balance dysfunction in patients after stroke.