Abstract
This thesis was undertaken to answer a question formed in clinical practice. This person of interest had a range of persistent post-concussion symptoms and had not responded to conventional health care. In short, he came to see me to help with his neck stiffness symptom. I applied an upper cervical mobilisation technique to this patient to help with his neck stiffness ONLY. However, this mobilisation helped improve all of this patient’s symptoms unrelated to his neck stiffness, including light sensitivity and exercise tolerance. Why did this response occur?
Why this response occurred was the catalyst for this thesis. It led to the literature review (chapter two), which explores the three main concepts of this thesis; (1) stress response, (2) manual therapy, and (3) persistent post-concussion symptoms. A scoping review was then undertaken to explore the extent of evidence for a dysfunctional stress response in individuals with persistent post-concussion symptoms (chapter three). This review only included studies that quantified dysfunction of the stress response, consisting of the autonomic nervous system and hypothalamic pituitary adrenal-axis, using non-invasive tools that can be utilised in the clinical setting. After much consideration, heart rate variability using a smartphone application was chosen to quantify autonomic nervous system activity, and salivary cortisol was selected to quantify hypothalamic pituitary adrenal-axis activity within each trial of this thesis. The first trial (chapter five) was a randomised controlled crossover trial that investigated whether mobilisation of the upper or lower cervical spine elicited a different autonomic nervous system or hypothalamic pituitary adrenal-axis response in healthy males. This led to the second trial (chapter six), which was a randomised controlled, parallel-design, proof-of-concept trial that investigated whether mobilisation of the upper or lower cervical spine elicited a different autonomic nervous system or hypothalamic pituitary adrenal-axis response in males with persistent post-concussion symptoms. Due to the similarities in some key aspects of the methodology between trials one and two, a methodological considerations chapter was included (chapter four). Additionally, due to the similarities between many parts of the methods in the first and second trials, a descriptive comparison was conducted between the response to cervical spine mobilisations and baseline values (chapter seven). The general discussion chapter (chapter eight) ties this thesis together, answering the ‘so what’ question. This chapter provides some explanation for the results, highlights some of the key learnings taken from this thesis and its implication for clinical practice and future research.
This body of work was undertaken to answer a clinically informed question. Therefore, it seems only fitting that this thesis concludes with a potential explanation as to why the above patients’ symptoms improved.