High prevalence of lumbar spinal stenosis in cases of idiopathic normal-pressure hydrocephalus affects improvements in gait disturbance after shunt operation

Hiroyuki Tominaga; Hiroto Tokumoto; Shingo Maeda; Ichiro Kawamura; Masato Sanada; Kazumasa Kawazoe; Eiji Taketomi; Noboru Taniguchi

doi:10.1016/j.wnsx.2023.100236

High prevalence of lumbar spinal stenosis in cases of idiopathic normal-pressure hydrocephalus affects improvements in gait disturbance after shunt operation

World Neurosurg X. 2023 Jun 21:20:100236. doi: 10.1016/j.wnsx.2023.100236. eCollection 2023 Oct.

Authors

Hiroyuki Tominaga¹, Hiroto Tokumoto¹, Shingo Maeda², Ichiro Kawamura¹, Masato Sanada¹, Kazumasa Kawazoe³, Eiji Taketomi⁴, Noboru Taniguchi¹

Affiliations

¹ Department of Orthopaedic Surgery, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, 890-8520, Japan.
² Department of Bone and Joint Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, 890-8520, Japan.
³ Department of Neurosurgery, Japanese Red Cross Kagoshima Hospital, 2545 Hirakawa, Kagoshima, 891-0133, Japan.
⁴ Department of Orthopaedic Surgery, Japanese Red Cross Kagoshima Hospital, 2545 Hirakawa, Kagoshima, 891-0133, Japan.

Abstract

Objective: Idiopathic normal-pressure hydrocephalus (iNPH) is characterized by symptoms of dementia, urinary incontinence, and gait disturbance; however, gait disturbance tends to persist after shunt surgery. Gait disturbance and urinary dysfunction are also major symptoms of lumbar spinal stenosis (LSS). Currently, the epidemiology of the complications of LSS in iNPH is unclear. Here, we evaluated the coexistence rate of LSS in iNPH cases.

Methods: This was a retrospective case-control study. Between 2011 and 2017, 224 patients with a median age of 78 years, including 119 males, were diagnosed with iNPH and underwent lumboperitoneal shunts or ventriculoperitoneal shunts. LSS was diagnosed with magnetic resonance imaging by two spine surgeons. Age, sex, body mass index (BMI), Timed Up and Go (TUG) test, Mini Mental State Examination (MMSE) score, and urinary dysfunction were examined. We compared the changes in these variables in the group of patients with iNPH without LSS versus those with both iNPH and LSS.

Results: Seventy-three iNPH patients (32.6%) with LSS had significantly higher age and BMI. The existence of LSS did not alter the postoperative improvement rates of MMSE and urinary dysfunction; however, TUG improvement was significantly impaired in the LSS-positive group.

Conclusions: LSS affects improvements in gait disturbance of iNPH patients after shunt operation. Because our results revealed that one-third of iNPH patients were associated with LSS, gait disturbance observed in iNPH patients should be considered a potential complication of LSS.

Keywords: Dural sac cross-sectional area; Idiopathic normal-pressure hydrocephalus; Lumbar spinal stenosis.