Mild gait impairment in long-term treated patients with neurological Wilson's disease

Abnormal gait is a frequently observed initial symptom of Wilson's disease (WD), which responds well to therapy, but has not been analyzed quantitatively so far. The question therefore is whether abnormalities can be detected by simple quantitative gait measurements in long-term treated Wilson-patients and whether these have a relation to clinical and laboratory findings.

In 30 long-term treated Wilson-patients, walking without aid at the preferred gait speed over a distance of 40 meters was analyzed. An Infotronic^® gait analysis system which consists of soft tissue shoes with two solid, but flexible plates each containing 8 force transducers was used to record the vertical component of the ground forces and the temporal patterns of foot ground contact. Gait parameters were correlated with clinical scores as well as laboratory findings. Results of Wilson-patients were compared to those of an age- and sex-matched control group.

Wilson-patients walked significantly (P<0.001) slower than normal subjects with equal step length, but lower cadence (P<0.001). Gait speed was negatively correlated with severity of neurological symptoms (r=-0.547; P<0.001) and positively with copper concentration in the 24 h urine (r=0.415; P<0.003). A negative correlation was also found between serum levels of liver enzymes and cadence (r=-0.515; P<0.001). Time normalized temporal patterns of walking were normal.

The temporal pattern of gait is normal in WD. A compliance dependent reduction of gait speed and cadence underline the necessity of careful long-term therapy monitoring in WD.