Across the globe, neck pain, mid-back pain, and low back pain (LBP) demonstrate high prevalence, incidence, disease burden, and economic costs [[1], [2], [3], [4], [5], [6], [7]], which arguably reflect inadequate care [8]. Back pain can be treated with various recommended pharmacological, surgical, behavioural, and non-pharmacological interventions [[9], [10], [11]]. However, non-pharmacological interventions like exercise, advice, and manual therapy are preferred first-line approaches [12,13], because back pain often improves over time regardless of treatment [14]. Among those non-pharmacological interventions, manual therapy appears to be less costly and more effective for patients with back pain [[15], [16], [17]]. In detail, manual therapies like spinal manipulations are recommended for back pain [14,18,19], showing low-to moderate-quality evidence for improved pain and function [[20], [21], [22], [23], [24], [25], [26]]. However, further research is needed due to methodological limitations [26]. Importantly, manual therapies and spinal manipulations are provided (with distinctions) by different healthcare professionals i.e. chiropractors, physiotherapists, and osteopaths [27]. Osteopaths combine manual therapy with psychological support and lifestyle advice [28] to provide person-centered care (informed by clinical reasoning, biopsychosocial perspectives, palpatory findings, and osteopathic principles and models [[29], [30], [31], [32]]) for patients with various medical conditions [33]. However, back pain is the most frequent reason to consult an osteopath and receive osteopathic manipulative treatment (OMT) [[34], [35], [36], [37]]. OMT was found to be safe and effective for back pain [38], leading to improved pain and function [[39], [40], [41], [42]]. To alleviate back pain, osteopaths employ a variety of manual techniques [43], which commonly include spinal manipulations (by means of high-velocity low-amplitude thrust techniques) [35,37,44]. Nonetheless, although OMT [[39], [40], [41], [42]] and spinal manipulations [[20], [21], [22], [23], [24], [25], [26]] improve back pain, the underlying mechanisms of action have not been established [39,[45], [46], [47]]. Recently, theories about the mechanisms underpinning spinal manipulations have moved from biomechanical to neurophysiological explanations [[48], [49], [50]]. Similarly, it was suggested that OMT acts through interoceptive, autonomic, and inflammatory mechanisms [51,52] by producing anti-inflammatory and hyper-parasympathetic effects mediated through interoceptive pathways [53]. To date, mixed evidence suggests that manual treatment (1) alters autonomic activity [[54], [55], [56], [57], [58], [59]] by improving autonomic outcomes in some studies [51,53,[60], [61], [62], [63], [64], [65], [66], [67]] but not others [[68], [69], [70], [71], [72], [73], [74]], and (2) influences inflammatory cytokines [[75], [76], [77]] by decreasing pro-inflammatory cytokines [[78], [79], [80], [81], [82], [83]] and increasing anti-inflammatory cytokines in some [84] but not all studies [85]. Further research is needed to draw definitive conclusions and evaluate the clinical relevance [59,[86], [87], [88]]. Regarding the mechanisms underlying these putative autonomic and inflammatory effects, it was speculated manual approaches influence autonomic activity by activating C-tactile fibers [61,71,89] and modulating the central autonomic nervous system [53,90], and inflammatory activity by disrupting neurogenic neuroinflammation through C- tactile fibers [52,91] and affecting fibroblast function and thereby cytokine secretion [92]. Importantly, a few studies have used infrared imaging to detect changes in skin temperature (ST) after OMT, showing increased ST in healthy subjects (hypothesized to result from a parasympathetic effect) [51], decreased ST in a back pain patient (hypothesized to result from an anti-inflammatory effect) [93], and decreased ST in healthy subjects (hypothesied to result from an anti-inflammatory or sympathetic effect) [94]. Beyond autonomic and inflammatory treatment effects, the osteopathic diagnosis may also be related to inflammatory changes. Osteopaths diagnose somatic dysfunctions [95] (Appendix A) by detecting palpatory signs of tissue texture abnormalities, asymmetry, restricted range of motion, and tenderness (TART) [96], which may partially evolve due to (low-threshold neurogenic and connective tissue) inflammation [52,83,91,97,98]. Thus, an osteopathic diagnosis might identify (palpable) inflammatory changes [99,100]. Although preliminary evidence suggested that the number of somatic dysfunctions correlates with cytokine concentrations in patients with LBP [83], the putative link between somatic dysfunctions and inflammatory activity has not been properly investigated but may be detectable with infrared imaging as ST changes can reflect underlying tissue inflammation [101]. Taken together, it may be worthwhile to investigate the putative mechanisms underpinning osteopathic diagnosis (detecting inflammatory changes) and osteopathic treatment (producing autonomic and inflammatory effects) with infrared imaging. Medical infrared thermography (MIT) detects physiological changes in ST by measuring infrared radiation [[102], [103], [104]]. It has been used for various medical conditions [105] and may aid in the diagnosis and therapy of spinal disorders [106]. MIT is a valid and reliable measure for quantifying spinal and paraspinal ST [107], which averages 32.1 °C (°C) in healthy subjects [108,109] with slight differences between spine regions and spine sides [[110], [111], [112]]. Compared to healthy subjects, the paraspinal ST of back pain patients is increased [[113], [114], [115]] or decreased [116] and differently distributed [117] without thermal asymmetry [118,119]. ST alterations in back pain were hypothesized to evolve due to increased inflammatory activity (leading to vasodilatation and increased ST) [[113], [114], [115],117,120,121], increased sympathetic activity (leading to vasoconstriction and decreased ST) [114,116,118,119,121], or increased muscle activity (leading to vasoconstriction and decreased ST) [117,119,[121], [122], [123]]. Beyond back pain, the effect of manual therapy on ST was evaluated in systematic reviews, which revealed mixed findings [59,124,125], no changes [126,127], or decreased ST [54,56,[128], [129], [130]]. However, few studies have focused on the back and spine. In healthy subjects, some studies reported increased ST of the back after manual treatment [[131], [132], [133], [134], [135]], while other studies found no changes, inconsistent results, or homogenised ST [[136], [137], [138], [139]]. In back pain patients, some studies demonstrated increased ST of the back after manual treatment [116,140], while others reported decreased ST [93,[141], [142], [143]] or no changes [144]. These inconsistent ST changes after manual therapy were hypothesized to evolve due to mechanical stimulation or changes in autonomic, inflammatory, or muscle activity [133,140,141]. Although further research is required, an increase in ST after manual treatment is arguably mediated by an autonomic (parasympathetic) response [71,145]. Before this background, it has been suggested that infrared imaging could “support the osteopathic approach to back pain” [93], including “the diagnosis of somatic dysfunction and the response to manipulative treatment” [146].