Jo Nijs

• PT, MT, PhD
• Professor at Vrije Universiteit Brussel

Even though nociceptive pathology has often long subsided, the brain of patients with chronic musculoskeletal pain has typically acquired a protective (movement-related) pain memory. Exercise therapy for patients with chronic musculoskeletal pain is often hampered by such pain memories. Here the authors explain how musculoskeletal therapists can al...

An increasing number of studies have examined how the immune system of patients with Chronic Fatigue Syndrome (CFS), or myalgic encephalomyelitis, responds to exercise. The objective of the present study was to systematically review the scientific literature addressing exercise-induced immunological changes in CFS patients compared to healthy contr...

Introduction: Central sensitization (CS) is present in a variety of chronic pain disorders, including whiplash, temporomandibular disorders, low back pain, osteoarthritis, fibromyalgia, headache, lateral epicondylalgia among others. In spite of our increased understanding of the mechanisms involved in CS pain, its treatment remains a challenging i...

The multicomponent intervention FIBROWALK integrates pain science education (PSE), therapeutic exercise, cognitive behavioral therapy (CBT), and mindfulness training for treating fibromyalgia (FM). This study investigated the effects of the FIBROWALK in online (FIBRO-On) and outdoor (FIBRO-Out) formats compared to treatment-as-usual (TAU) on core c...

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating disease, characterized by a diverse array of symptoms including post-exertional malaise (PEM), severe fatigue, and cognitive impairments, all of which drastically diminish the patients’ quality of life. Despite its impact, no curative treatments exist, largely due to the...

Background/Objectives: The International Association for the Study of Pain (IASP) recently introduced clinical criteria and a grading system to identify nociplastic pain, marking a pivotal step toward improving diagnostic accuracy. This study aimed to evaluate the reliability and validity of the IASP criteria using clinical vignettes, assessing the...

Background Current low back pain (LBP) treatment might be improved by tailoring treatments to subgroup characteristics. The Start Back screening Tool (SBT) and Central Sensitization Inventory (CSI) classify people with LBP into subgroups. It is currently unknown whether linear trends exist regarding somatosensory changes, psychological characterist...

Background/Objectives: White matter (WM) structural changes have been found in patients with chronic spinal pain (CSP). In these patients, pain neuroscience education followed by cognition-targeted exercise therapy (i.e., the Modern Pain Neuroscience Approach (MPNA)) was shown to be more effective than biomedically-focused education followed by sym...

Introduction The study’s primary goal is to investigate differences in postprandial glycaemic response (PPGR) to beverages with varying glycaemic index (i.e. low and medium) between breast cancer survivors (BCS) with chronic pain and healthy pain-free controls (HC). The secondary goal of the study is to investigate the potential link between PPGR a...

Breast cancer is the most common malignancy among women worldwide, and advances in early detection and treatment have significantly increased survival rates. However, people living beyond breast cancer often suffer from late sequelae, negatively impacting their quality of life. Prehabilitation, focusing on the period prior to surgery, is a unique o...

Advancements in clinical science have shown the necessity for a paradigm shift away from a biomedical toward a biopsychosocial approach. Yet, the translation from clinical science into clinical practice is challenging. The aim of this study was to assess the short-term and mid-term changes in pain knowledge and attitudes and guideline-adherent reco...

Background/Objectives: Dietary factors may significantly influence pain management in cancer survivors. However, a substantial gap exists regarding the relationship between nutrition and chronic pain in this population. This study examined differences in diet quality and dietary intake between breast cancer survivors (BCS) experiencing chronic pain...

Objectives To investigate the relationship between offset analgesia magnitude and the responsiveness to conditioned pain modulation (CPM), temporal summation of (second) pain (TSP), and clinical pain severity in people with knee osteoarthritis (KOA). Methods Electrical stimuli were applied to 88 participants with KOA to measure offset analgesia at...

Background Up to 30% of people infected with SARS-CoV-2 report disabling symptoms 2 years after the infection. Over 100 persistent symptoms have been associated with Post-Acute COVID-19 Symptoms (PACS) and/or long-COVID, showing a significant clinical heterogeneity. To develop effective, patient-targeted treatment, a better understanding of underly...

Background In individuals with chronic musculoskeletal pain, a reciprocal relationship between sleep and pain across short and long-term evaluations exists. Sleep influences pain levels, while the level of pain also impairs sleep. However, given the day-to-day variability of both sleep and pain intensity, assessing this relationship within a daily...

Background Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and fibromyalgia (FM) are comorbid disorders with overlapping symptoms. Research highlights autonomic dysfunction compared to healthy individuals, particularly involving the sympathetic branch. While past reviews focused on neurophysiological assessments, this systematic review...

Background/Objectives: To investigate if intra-articular biomarkers relate to peripheral and central sensitization in patients with late-stage knee osteoarthritis (KOA). Methods: A total of 17 (6M, 11F) patients (aged 69 ± 10 years) were assessed for peripheral (pressure pain thresholds (PPT)) and central (temporal summation (TS) and conditioned pa...

Introduction Pain is a prevalent side-effect seen in breast cancer survivors (BCS). Psychological factors are known role-players in pain mechanisms. Both pain and psychological factors contribute to or interact with healthcare use (HCU). However, the association between psychological factors and HCU has never been investigated in BCS with pain, whi...

In previous contributions to the Comprehensive Pain Management Editorial Series,we emphasized the importance of improving pain beliefs, stress tolerance, and sleep, as part of multimodal lifestyle approach for patients with chronci pain (defined as experiencing debilitating pain for at least 3 months). Where do we fit-in exercise therapy and/or phy...

Importance Insomnia is highly prevalent in patients with nonspecific chronic spinal pain (nCSP). Given the close interaction between insomnia and pain, targeting sleep problems during therapy could improve treatment outcomes. Objective To evaluate the effectiveness of cognitive behavioral therapy for insomnia (CBTi) integrated in best-evidence pai...

Chronic pain is a prevalent condition with a multifaceted pathogenesis, where epigenetic modifications, particularly DNA methylation, might play an important role. This review delves into the intricate mechanisms by which DNA methylation and demethylation regulate genes associated with nociception and pain perception in nociceptive pathways. We exp...

Background Sleep problems are commonly reported in people with knee osteoarthritis (KOA). Widely used commercial sleep trackers boost sleep awareness, prompting more people to monitor their sleep health with wearables. While it allows for continuous monitoring of sleep in a home setting, their accuracy in detecting sleep and wake, as well as sleep...

Chronic musculoskeletal pain and sleep problems/disorders exhibit a recognized bidirectional relationship; yet, systematic investigations of this claim, particularly in a prospective context, are lacking. This systematic review with meta-analysis aimed to synthesize the literature on the prospective associations between sleep problems/disorders and...

Purpose The primary aim of this cross-sectional study is to examine the prevalence of pain phenotypes in breast cancer survivors (BCS). A secondary aim entails examining whether health related quality of life differs between the main pain phenotypes in BCS. Methods BCS who experienced chronic pain were asked to complete the numeric pain rating sca...

Background: Impaired glucose regulation is suggested to be related to chronic low back pain (CLBP), although it is not clear how they interact with each other. Thus, the primary aim of this study was to investigate differences in postprandial glycemic responses (PPGRs) (the first sign of impaired glucose metabolism) to high- (sucrose) and low-glyce...

Background Many applied postgraduate pain training programs are monodisciplinary, whereas interdisciplinary training programs potentially improve interdisciplinary collaboration, which is favourable for managing patients with chronic pain. However, limited research exists on the development and impact of interdisciplinary training programs, particu...

Chronic pain is a source of substantial physical and psychological suffering, yet a clear understanding of the pathogenesis of chronic pain is lacking. Repeated studies have reported an altered behaviour of the salience network (SN) and default mode network (DMN) in people with chronic pain, and a majority of these studies report an altered behavio...

(1) Background: This exploratory study aims to explore the relationship between nonspecific chronic spinal pain (nCSP) and insomnia symptoms, by examining the interconnections, strengths, and directional dependence of the symptoms. In addition, we aim to identify the key symptoms of the nCSP–insomnia relationship and shed light on the bidirectional...

The potential to classify low back pain as being characterised by dominant nociceptive, neuropathic, or nociplastic mechanisms is a clinically relevant issue. Preliminary evidence suggests that these low back pain phenotypes might respond differently to treatments; however, more research must be done before making specific recommendations. Accordin...

Background In 2013, physical therapy students demonstrated low guideline-adherent recommendations regarding chronic low back pain (CLBP) for spinal pathology, activity, and work. Objectives To assess the differences in physical therapy students’ attitudes, beliefs, and adherence to guideline recommendations regarding CLBP and knee osteoarthritis...

Background Spinal stenosis is the most common reason for elective spine surgery, and the cardinal symptom is leg pain and discomfort when walking. Patients with spinal stenosis have a decreased level of physical activity and thereby an increased risk of poor health. Get Back is a person-centred digital programme that strives to support patients bei...

Chronic pain is the most prevalent disease worldwide, leading to substantial disability and socioeconomic burden. Therefore, it can be regarded as a public health disease and major challenge to scientists, clinicians and affected individuals. Behavioral lifestyle factors, such as, physical (in)activity, stress, poor sleep and an unhealthy diet are...

Introduction Current treatments for pain in breast cancer survivors (BCSs) are mostly biomedically focused rather than biopsychosocially driven. However, 22% of BCSs with pain are experiencing perceived injustice, which is a known predictor for adverse pain outcomes and opioid prescription due to increased maladaptive pain behaviour. Educational in...

Introduction Muscle strengthening training (MST) and behavioural graded activity (BGA) show comparable effects on knee osteoarthritic (KOA) pain, but the mechanisms of action remain unclear. Both exercise-induced anti-inflammation and central sensitisation are promising pathways for pain relief in response to exercise therapy in patients with KOA:...

OBJECTIVE: To explore whether preoperative pain intensity, pain cognitions, and quantitative sensory measures influence the established effectiveness of perioperative pain neuroscience education (PPNE) on health-related quality of life at 1 year after surgery for lumbar radiculopathy. DESIGN: Secondary analysis of a triple-blinded randomized contro...

Chronic pain is sustained, in part, through the intricate process of central sensitization (CS), marked by maladaptive neuroplasticity and neuronal hyperexcitability within central pain pathways. Accumulating evidence suggests that CS is also driven by neuroinflammation in the peripheral and central nervous system. In any chronic disease, the searc...

Objective Knee osteoarthritis (KOA) is a common musculoskeletal problem worldwide and its key symptom is pain. Guidelines recommend incorporating comorbidity-specific therapies into patient-centered care. Patients diagnosed with KOA frequently have insomnia, which is associated with higher pain severity. For this reason, this study protocol outline...

Background: Chronic spinal pain (CSP) is a major public health problem worldwide, frequently related to sleep problems. Central sensitization (CS) may worsen the clinical picture of CSP patients with insomnia. The aim of this study was to compare self-reported and objectively measured clinical outcomes between insomniac CSP patients with comorbid i...

Current evidence suggests that a group of patients who had survived coronavirus disease, 2019 (COVID-19) and developed post-COVID pain can exhibit altered nociceptive processing. The role of serological biomarkers and hospitalization treatments in post-COVID pain is unclear. This study aimed to investigate the association of serological biomarkers...

Fatigue and pain are the most common side effects impacting quality of life (QoL) in cancer survivors. Recent insights have shown that perceived injustice (PI) can play a substantial role in these side effects, but research on cancer survivors is scarce. Furthermore, guidelines for recognizing clinically relevant levels of PI in cancer survivors ar...

Introduction: Adhesive capsulitis, a condition marked by pain and stiffness of the shoulder, can have a frustrating clinical course for patients and health care professionals. Despite huge research interest, a universally accepted and used definition of clinical criteria for the diagnosis of adhesive capsulitis is currently still lacking. This sys...

Non-specific chronic low back pain (nCLBP) has been associated with nutrition. Yet, it is not clear how nutritional factors and nCLBP relate to one another. Therefore, the aim of the present study was to investigate differences in diet quality and dietary intake levels between nCLBP patients and healthy controls (HCs) and to explore the association...

This systematic review aimed to systematically investigate the literature on the effectiveness of exercise and physical activity programs on fatigue and sleep in people with arthritis. For that, seven databases were searched for relevant randomized controlled trials. After the searches, 36 studies investigating 2281 participants were included. Risk...

Background Many applied postgraduate pain training programs are monodisciplinary, while interdisciplinary training programs potentially improve interdisciplinary collaboration, which is favorable within the management of patients with chronic pain. However, there is limited research on the development and effectiveness of interdisciplinary training...

(1) Background: Noradrenaline and serotonin have modulatory roles in pain signaling and in exercise-induced hypoalgesia. Patients with chronic whiplash-associated disorders often show impaired exercise-induced hypoalgesia. Therefore, this study aimed to examine the isolated effect of activating serotonergic or noradrenergic descending pathways on h...

The brain can be organised into defined networks based on the coherent activity fluctuations between certain regions at rest when no external task or stimuli are applied. In patients with chronic pain, alterations in the way these networks act and interact become apparent, especially within the default mode network (DMN) and in the way it functiona...

Objective: to conduct and report a scoping review of the available evidence of the effects and content of pain neuroscience education for patients with persistent painful tendinopathies. Methods: PubMed, Embase, Web of Science, CINAHL, SPORTDiscus, and grey literature databases were searched from database inception to May 2022. Randomised and no...

Carpal tunnel syndrome (CTS) has been traditionally classified as primarily a neuropathic condition with or without pain. Precision medicine refers to an evidence-based method of grouping patients based on their susceptibility to biology, prognosis of a particular disease, or in their response to a specific treatment, and tailoring specific treatme...

(1) Background: Dysregulation in serotonergic and noradrenergic systems may be implicated in the neurobiophysiological mechanisms underlying pain-related cognitive impairment in chronic whiplash-associated disorders (CWAD). This study aimed to unravel the role of serotonergic and noradrenergic descending pathways in cognitive functioning at rest an...

Background: Perioperative education should be improved to decrease unfavourable outcomes after lumbar surgery. This trial aimed to compare effectiveness in terms of pain, quality of life, pain cognition, surgical experience, healthcare use, work resumption, and cost-effectiveness of perioperative pain neuroscience education (PPNE) vs traditional b...

Objectives: Physical exercise therapy is effective for some people with chronic nonspecific neck pain but not for others. Differences in exercise-induced pain-modulatory responses are likely driven by brain changes. We investigated structural brain differences at baseline and changes after an exercise intervention. The primary aim was to investiga...

Osteoarthritis (OA) is a leading cause of disability worldwide and clinical pain is the major symptom of OA. This clinical OA-related pain is firmly associated with symptoms of insomnia, which are reported in up to 81% of people with OA. Since understanding the association between both symptoms is critical for their appropriate management, this nar...

Sleep disturbances are one of the most frequent reported problems in people with nonspecific chronic spinal pain (nCSP) and presents an additional treatment challenge. Interventions targeting sleep problems are mainly based on subjective sleep complaints and do not take objective sleep into consideration. The aim of this cross-sectional study was t...

Background: A large proportion of people who sustain a whiplash injury will have persistent pain, disability, and participation problems. Several prognostic factors for functional recovery have been reported in the literature but these factors are often evaluated based on differing implementations in clinical practice. Additionally, physiotherapis...

Stress has been consistently linked to negative impacts on physical and mental health. More specifically, patients with chronic pain experience stress intolerance, which is an exacerbation or occurrence of symptoms in response to any type of stress. The pathophysiological mechanisms underlying this phenomenon remain unsolved. In this state-of-the-a...

Myofascial pain syndrome is featured by the presence of myofascial trigger points (TrPs). Whether TrPs are primary or secondary phenomena or if they relate to central or peripheral nervous system disorders is controversial. Referred pain, a cardinal sign of TrPs, is a central phenomenon driven by peripheral input. In 2021, the International Associa...

Background: Perceived injustice (PI) is a multidimensional appraisal cognition comprising the severity of loss consequent to injury, blame, a sense of unfairness, and/or irreparability of loss. PI gained increasing interest in pain research since it potentially contributes to the experience and burden of (chronic) pain. Objectives: This systemat...

Pain after a SARS‐CoV‐2 acute infection (post‐COVID pain) is becoming a new healthcare emergency but remains underestimated and most likely undertreated due to a lack of recognition of the phenomenon and knowledge of the underlying pain mechanisms. Evidence supporting any particular treatment approach for the management of post‐COVID pain is lackin...

Background: The clinical presentation and pain experience of patients with (sub)-acute low back pain ((S)ALBP) can strongly vary in clinical practice. However, despite growing evidence that psychological factors are associated with disability in chronic pain conditions including low back pain, studies examining the influence of psychological facto...

Purpose This systematic review and meta-analysis aimed to determine the effectiveness of psychologically informed practice (PIP) with behavioural graded activity (BGA) compared to (1) waitlist controls (WLC), (2) other interventions (OI), (3) PIP alone or (4) BGA alone in cancer patients and survivors (CPaS). Methods PubMed, Web of Science and Emb...

Pain after cancer remains underestimated and undertreated. Precision medicine is a recent concept that refers to the ability to classify patients into subgroups that differ in their susceptibility to, biology, or prognosis of a particular disease, or in their response to a specific treatment, and thus to tailor treatment to the individual patient c...

To manage chronic pain, multidisciplinary interventions have been increasingly deployed , mostly in secondary or tertiary care settings. Evidence on the effectiveness of multidisciplinary intervention within primary care is scarce. This study examined the effectiveness of a primary care multidisciplinary treatment for chronic pain compared with tre...

This cross-sectional study explored associations between demographics, pain intensity and cognitions on the one hand and healthcare use (HCU) on the other hand in people undergoing surgery for lumbar radiculopathy. HCU during the 2 months preceding surgery was evaluated using a retrospective questionnaire. Demographics included sex, age and level o...

Background: In the pathogenesis of knee osteoarthritis (KOA), inflammatory mediators play an important role. However, the precise underlying mechanism by which regular exercise therapy (ET) exert effects on the immune system in KOA patients is unknown. Objectives: The aim of this systematic review was to investigate the basal and acute effects o...

In low back pain (LBP), primary care and secondary prevention of recurrent and persistent LBP are not always successful. Enhanced understanding of neural mechanisms of sensorimotor processing and pain modulation in patients with acute LBP is mandatory. This explorative fMRI study investigated sensorimotor processing due to mechanosensory stimulatio...

Introduction: The On&Out study is aimed at assessing the effectiveness, cost-utility and physiological underpinnings of the FIBROWALK multicomponent intervention conducted in two different settings: online (FIBRO-On) or outdoors (FIBRO-Out). Both interventions have proved to be efficacious in the short-term but there is no study assessing their com...

Background Catechol-O-methyltransferase (COMT) has been shown to influence clinical pain, descending modulation, and exercise-induced symptom worsening. COMT regulates nociceptive processing and inflammation, key pathophysiological features of Chronic Fatigue Syndrome and Fibromyalgia (CFS/FM). We aimed to determine the interactions between genetic...