Abstract
Achilles tendinopathy is a common musculoskeletal condition that contributes to pain and disability in both the active and sedentary populations. It’s pathogenesis is complex, and therefore it can be difficult to treat. For this reason, there are continuing investigations exploring new treatment options. Recently, there is increasing interest in the mechanisms through which spinal mobilisation techniques achieve hypoalgesia. Hypoalgesia is observed to occur together with excitation of the sympathetic nervous system. However, there is an absence of current data investigating the mechanisms through which manipulation, distinct from a mobilisation technique, might influence pain in the treatment of AT. There is also an absence of data regarding the longer-term effects of these techniques on pain and function. Recent studies identified changes in autonomic behaviour in Achilles tendons with tendinopathy: it is anticipated these changes might contribute to the mechanism of pain, and perhaps the pathogenesis of AT. Therefore, the effect of spinal manipulation on the autonomic nervous system may be highly important in the treatment of AT. With this in mind, an investigation into the effect of spinal manipulation on longer-term outcome measures of pain and function, together with an assessment of changes in autonomic function, is justified.
Aims:
1. Complete a systematic review on the studies that have investigated the effect of spinal mobilisation on the sympathetic nervous system.
2. Review the literature investigating the effect of spinal manipulation on the sympathetic nervous system
3. Design a pilot study to assess for changes in pain and function between two groups of participants with Achilles tendinopathy.
4. Investigate changes in sympathetic activity following spinal manipulation.
5. Assess the effectiveness of the study protocols and procedures.
Methods:
The systematic review was completed according to PRISMA (www.prisma-statement.org) guidance.
For the pilot study, a total of 17 participants were randomised into either the manipulation group or the standard care group. Each group received a standardised eccentric exercise regime, and received two physiotherapy appointments per week, for four weeks, to monitor their exercise regime. In addition, the manipulation group received manipulation to the thoracic spine during each visit. After the initial four-week period participants were offered one follow-up appointment to monitor their exercise regime every two weeks until the end of the trial.
The Victorian Institute of Sports Assessment – Achilles questionnaire, and a pain score were used to assess for changes in pain and function at baseline; week four and week 12. Changes in heart rate and blood pressure were used to assesse for changes in sympathetic nervous system activity following spinal manipulation or a rest intervention.
Data Analysis:
An analysis of covariance (ANOVA) assessed for changes within and between groups over the 12-week trial period.
Results:
Results of the systematic review established there was strong evidence for sympathetic excitation following spinal mobilisation..
Results of the pilot study demonstrated a significant difference in VISA-A scores within (p<0.01) and between groups (p<0.01), favouring the manipulation group. A significant difference in pain scores within (p<0.01) and between groups (p=0.03) was also demonstrated, favouring the manipulation group. There was no statistically significant change in blood pressure or heart rate within or between groups.
Conclusion:
This evidence suggests that a thoracic spine manipulation, as an adjunct to eccentric exercises, may be of benefit in the treatment of Achilles tendinopathy. The measures used here did not suggest an effect mediated by the ANS.