Abstract
Purpose and Background: Physiotherapeutic management of lumbar disorders often incorporates specific manual therapy techniques of which McKenzie’s lumbar extension exercises (EIL) and segmental rotational grade V manipulation are popular options. The use of proxy measures of sympathetic nervous system (SNS) activity (skin conductance) is a recognised method of ascertaining neurophysiological responses to physiotherapy treatment but have yet to be used to assess magnitude of response to lumbar techniques. This preliminary study aimed to investigate the neurophysiological effects of these two treatment techniques.
Methodology: A quasi-experimental, independent group’s design was utilised, with random allocation of 50 normal, healthy participants (25 per group) into a manipulation group or an EIL group. Non-invasive neurophysiological measurements of skin conductance were taken as a proxy-measure of sympathetic nervous system (SNS) activity in the lower limbs before, during and after the administration of the techniques. Results were calculated using Area Under the Curve readings and converted into percentage change calculations for the intervention and the post-intervention periods.
Results: Both treatments increased SNS activity during the intervention period, 76% for the manipulation group (p=0.0005) and 35% for EIL group (p=0.0005) with the manipulative technique having significantly greater effect (p=0.012). Further analysis of the manipulation group found no difference between the ‘opening’ and the ‘closing’ side of the technique (p=0.76).
Conclusion: Preliminary evidence now exists supporting the neurophysiological effects of two lumbar techniques and that manipulation has a greater magnitude of effect over the EIL technique. Future research, on a low back pain patient population, is proposed and projected sample size calculations computed.
Correspondence should be addressed to SBPR at the Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PE, England.
