35. Effect of surgical intervention on gait function in patients with symptomatic lumbar canal stenosis

Abstract

<h3>BACKGROUND CONTEXT</h3> Gait impairment is one of the primary symptoms of degenerative lumbar canal stenosis (LCS), yet it is poorly understood due to a lack of quantitative data on kinematics and kinetics during the gait. Gait analysis is a well-established tool for the quantitative assessment of gait disturbances, providing a functional diagnosis, assessing treatment plan and monitoring of disease progress. <h3>PURPOSE</h3> To analyze the effect of decompression surgery on gait characteristics in patients with LCS. <h3>STUDY DESIGN/SETTING</h3> Prospective non-randomized comparative study at a teaching hospital. <h3>PATIENT SAMPLE</h3> Eighteen patients with symptomatic LCS and 18 healthy volunteers. <h3>OUTCOME MEASURES</h3> Gait quality: spatiotemporal, kinetic and kinematic parameters functional outcome: ODI, VAS. <h3>METHODS</h3> Eighteen patients with single-level LCS and 18 healthy volunteers were prospectively recruited. All the patients with symptomatic LCS underwent TLIF (transforaminal lumbar interbody fusion) surgery. Gait analysis was perfomed preoperatively and six months postoperatively as per standard protocol. The spatiotemporal, kinematic and kinetic parameters were analyzed. The Kolmogorov-Smirnov test and coefficient of skewness and kurtosis was used to assess the normality of distribution. Pre- and postoperative clinical outcomes, spatial-temporal, kinetic and kinematic data were compared with the paired t-test or Wilcoxon signed-rank test according to the normality of the distribution. Unpaired t-test was used to compare the two groups. Stepwise linear regression models were used to detect significant relationships between changes in ODI and VAS score, and parameters describing gait function. <h3>RESULTS</h3> Significant improvement was noted in ODI (p < 0.05) and VAS scores (p < 0.05) six months post-surgery. Spatiotemporal (Stride time [p=0.01], Swing phase % [p=0.01], Double support phase % [p=0.02], Mean velocity [p < 0.01], Cadence [p < 0.01], Stride length [p < 0.01], Step length [p < 0.01] and step width [p < 0.01])and kinetic parameters (peak hip [p < 0.01], knee [p < 0.01] and ankle power [p < 0.01], vertical GRF [p=0.01]) were significantly better following surgery, reaching normal levels when compared to healthy individuals. The kinematic parameters (trunk tilt [p=0.02], peak hip extension [p < 0.01], peak knee flexion in stance [p=0.01] and swing phase [p < 0.01], peak ankle dorsiflexion in stance [p < 0.01] and swing phase [p=0.04], GPS [p < 0.01] and GDI [p < 0.01]) were significantly improved following surgery but did not reach normal levels when compared to controls. A significant correlation was found between change in ODI and VAS score with change in certain kinematic parameters (knee power, stance time, ankle plantarflexion, peak ankle dorsiflexion moment, GDI, swing time, peak ankle dorsiflexion in swing, peak hip and knee flexor moment). <h3>CONCLUSIONS</h3> Decompression surgery in LCS produces improvement in gait parameters, pain scores, and functional outcome that significantly improves walking tolerance and speed. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.