Human Studies

The main symptoms of fibromyalgia comprise diffuse pain, disability, depressive symptoms, catastrophizing, sleep disruption and fatigue, associated with dysfunction of the descending pain-modulating system (DPMS).

Fibromyalgia is a prevalent pain condition that is associated with cognitive impairments including in attention, memory, and executive processing. It has been proposed that fibromyalgia may be caused by altered central pain processing characterised by a loss of endogenous pain modulation. We tested whether attentional analgesia, where cognitive engagement diminishes pain percept, was attenuated in fibromyalgia patients (n=20) compared to matched healthy controls (n=20). An individually calibrated, attentional analgesia paradigm with a 2×2 block design was used with brain and brainstem-focussed fMRI. Fibromyalgia patients had both lower heat pain thresholds and speeds in a visual attention task. When this was taken into account for both attentional task and thermal stimulation, then both groups exhibited an equivalent degree of attentional analgesia. fMRI analysis showed similar patterns of activation in the main effects of pain and attention in the brain and brainstem (with the sole exceptions of increased activation in the control group in frontopolar cortex and the ipsilateral locus coeruleus). The attentional analgesic effect correlated with activity in the periaqueductal grey and rostroventromedial medulla. These findings indicate that fibromyalgia patients can engage the descending pain modulatory system if the attentional task and noxious stimulus intensity is appropriately titrated.

Pediatric chronic post-surgical pain is a surgical complication associated with various levels of functional limitation. Two commonly used measures of functional limitations in youth are the Functional Disability Inventory (FDI) and the PROMIS Pediatric Pain Interference Scale (PPIS), where the former is general, and the latter, pain specific. The aim of the present study was to prospectively compare pre-surgical youth and parent risk factors for youth functional limitations, assessed by the FDI and PPIS, 12 months after major pediatric surgery. Risk factors for the FDI and PPIS were compared in 79 dyads consisting of youth (58% female, = 14.56 years; SD = 2.31) undergoing major surgery and one of their parents. The FDI and PPIS were highly correlated prior to surgery ( = 0.698, < 0.001) and even more so 12 months after surgery ( = 0.807, < 0.001). Parent pre-surgical anxiety sensitivity and youth pre-surgical functional disability significantly predicted 12-month FDI ((6,56) = 4.443, = 0.001, Adjusted R = 0.25), whereas parent pre-surgical anxiety sensitivity, trait anxiety, pain anxiety, as well as youth pain-related anxiety and worry significantly predicted 12-month PPIS ((6,45) = 4.104, = 0.002, Adjusted R = 0.27). Risk factors for 12-month general and pain-specific functional limitations differ by dyad member and type. Functional limitations in youth after surgery are predicted by youth and parent factors, however the risk factors differ between the FDI and the PPIS.

Virtual reality (VR) facilitates physical therapy (PT) via improved engagement. While shown to benefit specific patient populations, such as stroke patients, it is less established in otherwise healthy adults and children receiving outpatient PT. The primary objective was to compare total PT-guided Movement supplemented with VR (PTMVR) to PT guided Movement alone, without VR (PTM).

Diabetic peripheral neuropathy (DPN) is a chronic complication of diabetes mellitus associated with high morbidity and mortality. Major risk factors for DPN include metabolic changes, duration of diabetes, nerve ischaemia and derangements in regeneration and nerve repair programs. Chemokines have been previously implicated in the pathogenesis of various neuropathies and neuropathic pain processes. The aim of this pilot study was to evaluate the association between plasma levels of chemokines (CXCL9, CXCL10 and CXCL11) with the presence of DPN in a cohort of type 2 diabetes (T2D) patients.