Characteristics of Postural Sway during Quiet Standing Before and After the Occurrence of Neurogenic Intermittent Claudication in Female Patients with Degenerative Lumbar Spinal Canal Stenosis

[Purpose] This study investigated the effect of neurological symptoms and/or signs after the occurrence of neurogenic intermittent claudication (NC) on postural sway during quiet standing of patients with lumbar spinal canal stenosis (LSS). [Subjects and Methods] Thirty-two female patients with LSS at the L4/5 level were studied. We measured the path of center of foot pressure (COP) during quiet standing with eyes open for 30 s using a stabilometer before and after the occurrence of NC. [Results] The total path length of COP (LC) and area surrounded by the outline of the path of COP (AC) significantly increased after NC. Body mass index (BMI) correlated with both the NC rate (after NC/before NC) of LC and that of AC. The average lateral COP displacement from the center of the base of support (COP(RL)) before NC was located on the asymptomatic side from the center of the base of support in 29 of 32 patients. After NC, COP(RL) moved to the symptomatic side in 31 patients. [Conclusion] These results suggest that patients with LSS are at risk of falling after NC, especially those with high BMI.