Effect of Different Neurodynamic Mobilization Techniques on Knee Extension Range of Motion in the Slump Position

Abstract

Mobilization of the nervous system has emerged as a significant adjunct to the treatment of musculoskeletal injuries. Clinical studies have shown that neurogenic symptoms can be resolved by treatment techniques directed at restoring normal neural biomechanics and physiology. Two alternate mobilization techniques have been proposed: the slider and tensioner techniques. A search of the literature revealed no peer-reviewed studies comparing the effects of these two treatment techniques, although a number of studies have investigated these techniques in isolation and found them to have positive effects on range of motion and other outcome measures. The aim of this study was to investigate the effects of these two techniques on knee range of motion of normal subjects (30 females [mean age 21.4+/?1.2 years, range 19-24]) in the slump position. Knee flexion angle of the right leg was measured using a universal 360° goniometer while in a fully slumped position, prior to and after the application of the respective mobilization technique. The tensioner technique brought about a significant decrease in knee flexion angle (P=0.003) with a mean percentage change of 14.7+/?11.8%(3.4+/?2.5°). The slider technique brought about a significant decrease in knee flexion angle (P<0.001) with a mean percentage change of 19.9+/?15%(4.3+/?2.6°). There was a non-significant between-group difference for the effect of the two techniques on range of motion (P=0.075). The findings of this study indicate that in normal female subjects, both the tensioner and slider techniques have a positive and significant effect on improving knee extension range of motion in the slump position. This could decrease the sensitivity of the sciatic nerve and the neuromeningeal structures to mechanical load. The clinical significance of changes of this magnitude on neural tissue and of these techniques in a symptomatic population requires further investigation.