Normal sensory responses to variations in sequencing for the neurodynamic slump test

Abstract

Background: The neurodynamic slump test is commonly used in all forms of manual therapy to evaluate the nerve mechanics and physiology of the central and peripheral nervous systems. Clinicians have proposed that the order of slump test sequencing is interchangeable and that neural structures will be subjected to different mechanical loads depending upon the order of joint movement.

Aims: The aims of this study were to: (1) investigate the normative sensory responses (frequency, anatomical location, symptom intensity, symptom descriptors) associated with sequences of the slump test in asymptomatic participants; and (2) investigate the body segment angles associated with sequences of the slump test in asymptomatic participants.

Methods: Each asymptomatic male participant (n=24; mean age = 27 ± 2.3 y; mean BMI = 24.3 kg/m2) performed four variations of the slump test. Digital photography was used to measure 5 body segment angles. A body chart, visual analogue scale and 12 sensory descriptors were administered.

Results: There were no clinically important differences in the sensory responses, or significant differences (1-way ANOVA, all contrasts p≥0.77) for any body segment angles between variations of different sequences of the slump test. Nearly all participants (n=23/24) in all tests reported a sensory response with pain and/or discomfort most commonly located in the lower limb (> 80%). “Stretching” was the most common (50%) descriptor selected during the end stage of the slump test. Pooling all sequences, a majority of participants (n=85/96) experienced a decrease in intensity of symptoms with cervical extension, which was observed largely independent of the slump sequence.

Conclusion: A change in the sequence of a standardised slump test in asymptomatic participants did not meaningfully influence the outcome of the sensory responses or body segment angles in this sample. Secondarily, these findings indicate that a sensory response arising from slump occurs in people who are asymptomatic.