F波による腰部脊柱管狭窄症手術例における安静時しびれの予後予測

Can the F-wave Predict Persistence of Resting Numbness after Surgery in Lumbar Spinal Canal Stenosis?

　安静時足底しびれを有する腰部脊柱管狭窄症9例16肢（2例2肢は除外）を対象に除圧術前後のF波を測定し，安静時しびれの予後予測のパラメータとなり得るかを検討した．術後安静時しびれが改善した7肢中6肢では術前のF波最小潜時は33.0ms/m未満であった．術後安静時しびれの改善がなかった9肢中8肢では，術後のF波潜時は2.0ms/m以上改善するものの，術前のF波潜時は33.0ms/mを超えていた．術前のF波潜時が足底部の安静時しびれの術後予測の指標となる可能性が示唆された．

　Before and after decompressive surgery the F-wave was measured in 16 lower extremities of 9 patients with lumber spinal canal stenosis (1 extremity each of 2 patients was removed) who had resting plantar numbness. Our hypothesis was that the F-wave can be used to predict the persistence of resting numbness after surgery. In 6 of the 7 extremities in which resting numbness improved postoperatively, the minimum latency (ML) of the preoperative F-wave was under 33.0ms/m. In 8 of the 9 extremities in which there was no improvement of resting numbness postoperatively, the ML of the preoperative F-wave exceeded 33.0ms/m, although the ML of the F-wave was shortened more then 2.0ms/m postoperatively. The preoperative ML of the F-wave can be used as predictor of persistence of resting plantar numbness after surgery for lumber spinal canal stenosis.