Effect of leg dominance, gender and age on sensory responses to structural differentiation of straight leg raise test in asymptomatic subjects: a cross-sectional study

Abstract

Study design: Cross-sectional study.Objectives: To assess the effect of structural differentiation on sensory responses of asymptomatic individuals to standard neurodynamic tests of straight leg raise (SLR) and to evaluate the relevance of leg dominance, gender, and age.Background: SLR test is a well-known neurodynamic test among physical therapists; no studies to date have investigated the influence of gender, age, and leg dominance to the sensory responses of this neurodynamic test and its structured differentiating maneuver.Methods: Thirty (16 women) asymptomatic individuals enrolled in this study. Dominancy test was performed for each participant. Pain intensity using visual analogue scale (VAS), symptoms location in a body chart, nature of symptoms evoked, and hip range of motion (ROM) were recorded and compared at ankle neutral position (N-SLR) and dorsiflexion (DF-SLR) in both legs at the point of pain tolerance during SLR (P2). In addition, hip ROM was recorded at the onset of pain (P1).Results: There was a statistically significant sex main effect for P1 and P2 between N-SLR and DF-SLR (p < 0.05). Mean hip ROM during the SLR was more than 10° greater in women than men. There was no statistically significant interaction between leg dominance and age group in N-SLR, DF-SLR, and VAS. Pain intensity was moderate for each SLR test. Symptoms most often described were stretch (96.7%), followed by tightness (70%) in the posterior thigh and leg.Conclusions: SLR hip ROM is influenced by sex in asymptomatic individuals, leading to a greater hip ROM in SLR in women. Age and limb dominance are not relevant to SLR hip ROM or pain intensity.