Jo Perry

Sympathetic nervous system effects in the hands following a grade III postero-anterior rotatory mobilisation technique applied to T4: A randomised, placebo-controlled trial

Joint mobilisation to the T4 vertebra has been advocated as a treatment for T4 syndrome. To date no controlled studies have investigated the effects of thoracic spinal manual therapy (SMT) applied to T4 on sympathetic activity in the hands. This study investigated whether a grade III postero-anterior rotatory joint mobilisation technique applied to the T4 vertebra at a frequency of 0.5 Hz had demonstrably greater effects than a validated placebo intervention on skin conductance (SC) in the hands of healthy subjects. A power analysis calculation was performed and using a double blind, placebo-controlled, independent groups design, 36 healthy subjects (18-35 years) were randomly assigned to two groups (placebo intervention or treatment intervention). A BioPac unit recorded continuous SC measures before, during and after each experimental intervention. An exit questionnaire was used to validate the expectancy effects of the placebo intervention. Results demonstrated a significant difference between groups in SC in the right hand during the post-treatment rest period (F = 4.888, p = 0.034); with the treatment intervention being sympathoexcitatory in nature. A trend towards a significant difference between groups was also demonstrated in the left hand during the rest period (F = 4.072, p = 0.052). This study provides preliminary evidence that joint mobilisation applied to the T4 vertebra at a frequency of 0.5 Hz can produce sympathoexcitatory effects in the hand. Further research is recommended in a patient population.

Investigation of the effects of a centrally applied lumbar sustained natural apophyseal glide mobilization on lower limb sympathetic nervous system activity in asymptomatic subjects.

OBJECTIVE The purpose of this study was to investigate the effects of a manual mobilization technique on indirect measures of sympathetic nervous system activity. METHODS Forty-five healthy volunteers participated in this randomized, single-blinded, parallel-group 3-arm design (experimental, sham [placebo], and control group), comprising 15 subjects each. For the experimental group, lumbar mobilization involving an active movement, the Mulligan sustained natural apophyseal glide (SNAG), was applied on L4 spinous process by an experienced manual therapist. Sustained natural apophyseal glides were performed in sitting with active flexion (6 times × 3 sets). The sham technique simulated the SNAG without applying any force. In the control group, participants were placed in a static sitting position throughout the experiment. Measures of skin conductance in the lower limbs (L4 dermatome) were recorded to reflect sympathetic nervous system activity in the preintervention, periintervention, and postintervention periods. Differences in percentage change of skin conductance were analyzed with analysis of variance and post hoc tests. RESULTS Lumbar SNAG produced sympathoexcitation compared with the control group in the intervention period (P = .04). No significant difference was found between SNAG and sham groups, and no statistically significant difference was found between groups in the final rest period. CONCLUSION The results of this study showed that, in asymptomatic participants, both lumbar SNAG and sham techniques performed on L4/5 intervertebral joint with active flexion induced a sympathoexcitatory response in lower limbs compared with the control group.

The effects of the Bowen technique on hamstring flexibility over time: A randomised controlled trial

The hamstring muscles are regularly implicated in recurrent injuries, movement dysfunction and low back pain. Links between limited flexibility and development of neuromusculoskeletal symptoms are frequently reported. The Bowen Technique is used to treat many conditions including lack of flexibility. The study set out to investigate the effect of the Bowen Technique on hamstring flexibility over time. An assessor-blind, prospective, randomised controlled trial was performed on 120 asymptomatic volunteers. Participants were randomly allocated into a control group or Bowen group. Three flexibility measurements occurred over one week, using an active knee extension test. The intervention group received a single Bowen treatment. A repeated measures univariate analysis of variance, across both groups for the three time periods, revealed significant within-subject and between-subject differences for the Bowen group. Continuing increases in flexibility levels were observed over one week. No significant change over time was noted for the control group.

A randomised, independent groups study investigating the sympathetic nervous system responses to two manual therapy treatments in patients with LBP

Manual therapy (MT) and exercise therapy techniques are commonly utilised, guideline recommended treatment strategies in the management of non-specific low back pain (LBP). Preliminary evidence on asymptomatic participants indicates that two manual therapy techniques; repeated lumbar extension in lying exercise (EIL); and segmental rotational grade V manipulation (manipulation), have significant effects on the sympathetic nervous system (SNS) as detectable with skin conductance (SC) responses. However, it is not known if these responses occur in patients with LBP. A randomised, independent groups design was utilised to investigate the immediate SC responses in 50 patients with LBP of less than 12 weeks duration. Patients received either the manipulation technique (n = 25) or the EIL exercise (n = 25) and SC activity was recorded, in a single treatment session, pre-, peri- and post-treatment. Both treatments resulted in a sympatho-excitatory response during the intervention period with the manipulation technique having a 255% increase (p < 0.005), and the EIL technique a 94% increase (p = 0.019) with both treatments having responses that were sustained into the final rest period (p < 0.005). Between-group comparisons indicate that the manipulation technique had a significantly greater magnitude of effect (p < 0.001). The results support the sympatho-excitatory responses seen in normative studies but challenge the assumption that normative and patient populations are analogous with respect to the magnitude of effect observed and suggest that SC responses may be a feasible, proxy method of detecting dorsal horn sensitisation and neuro-plastic adaptations occurring in the presence of LBP.

The effects of a modified spinal mobilisation with leg movement (SMWLM) technique on sympathetic outflow to the lower limbs

Physiotherapy management of lumbar disorders, based on Mulligans mobilization techniques, is a treatment of choice by many physiotherapists, however, there is only limited evidence of any neurophysiological effects and much of this has focused on the cervical spine and upper limbs. This study aims to extend the knowledge base underpinning the use of a modified Mulligans spinal mobilisation with leg movement technique (SMWLM) by exploring its effects on the peripheral sympathetic nervous system (SNS) of the lower limbs. Using a single blind, placebo controlled, independent groups study design, 45 normal naive healthy males were randomly assigned to one of three experimental groups (control, placebo or treatment; SMWLM). SNS activity was determined by recording skin conductance (SC) obtained from lower limb electrodes connected to a BioPac unit. Validation of the placebo technique was performed by post- intervention questionnaire. Results indicated that there was a significant change in SC from baseline levels (30%) that was specific to the side treated for the treatment group during the intervention period (compared to placebo and control conditions). This study provides preliminary evidence that a modified SMWLM technique results in side-specific peripheral SNS changes in the lower limbs.

A Longitudinal Observational Clinical Study of Neurophysiological and Patient-Reported Responses to a Program of Physiotherapy for Acute and Subacute Low Back Pain

Objectives: The purpose of this study was to document the baseline neurophysiological status (skin conductance activity levels) of patients presenting for physiotherapy with acute and subacute low back pain (symptoms of up to 12 weeks’ duration) and to observe the magnitude and direction of sympathetic nervous system (SNS) changes (skin conductance responses [SCRs]) occurring as a result of receiving guideline‐endorsed physiotherapy treatment. Methods: A pragmatic, prospective, longitudinal, observational study recording SNS skin conductance (SC) responses and patient reported outcome measure changes to a program of guideline‐endorsed physiotherapy treatment for low back pain symptoms of up to 12 weeks’ duration. Sixty patients received a guideline‐endorsed physiotherapy treatment program. Continuous neurophysiological recordings of SC activity levels were taken throughout each treatment. Patient reported outcome measure data were extracted from inception, midpoint, and discharge. Within and between treatment analyses determined the nature of SC changes and correlations to longitudinal changes in pain and function. Skin conductance changes were measured within and between treatment episodes at treatment inception, midpoint, and discharge and observed correlations between the magnitude of SCRs, pain abatement (numeric pain rating scale), and functional restoration (Oswestry Disability Index). Results: Skin conductance changes were significant during all “treatment” periods (P = .044), with the greatest magnitude of sympathoexcitatory responses occurring at inception (219%). The treatment modality providing the maximum SNS response was a high‐velocity lumbar rotation manipulation. Positive correlations were identified between SCRs, Oswestry Disability Index improvements (r = 0.82, P < .0005), and pain abatement (r = 0.459, P < .0005). Conclusions: Patients with low back pain exhibited neurophysiological treatment responses indicative of a symptom‐related neuroplastic state of dorsal horn sensitization that may be receptive to early manual therapy intervention.