Mark J. Catley

Normative health-related fitness values for children: analysis of 85347 test results on 9–17-year-old Australians since 1985

Objectives To provide sex- and age-specific normative values for health-related fitness of 9–17-year-old Australians. Methods A systematic literature search was undertaken to identify peer-reviewed studies reporting health-related fitness data on Australian children since 1985—the year of the last national fitness survey. Only data on reasonably representative s amples of apparently healthy (free from known disease or injury) 9–17-year-old Australians, who were tested using field tests of health-related fitness, were included. Both raw and pseudo data (generated using Monte Carlo simulation) were combined with sex- and age-specific normative centile values generated using the Lambda Mu and Sigma (LMS) method. Sex- and age-related differences were expressed as standardised effect sizes. Results Normative values were displayed as tabulated percentiles and as smoothed centile curves for nine health-related fitness tests based on a dataset comprising 85347 test performances. Boys typically scored higher than girls on cardiovascular endurance, muscular strength, muscular endurance, speed and power tests, but lower on the flexibility test. The magnitude of the age-related changes was generally larger for boys than for girls, especially during the teenage years. Conclusion This study provides the most up-to-date sex- and age-specific normative centile values for the health-related fitness of Australian children that can be used as benchmark values for health and fitness screening and surveillance systems.

Is tactile acuity altered in people with chronic pain? A systematic review and meta-analysis

UNLABELLED Impaired tactile acuity in people with chronic pain conditions has been suggested to reflect altered cortical representation of the painful body part, and treatments that aim to improve tactile acuity in these conditions have shown clinical benefit. Whether abnormalities in tactile acuity are a consistent feature of chronic pain remains largely unknown. The aim of this review was to systematically evaluate the literature and use meta-analysis to establish whether tactile acuity is altered in people with chronic non-neuropathic pain. We systematically searched the literature for studies that investigated tactile acuity in people with chronic non-neuropathic pain and compared it to an appropriate control group. Sixteen studies, reporting data from 5 chronic pain conditions, were included. Data were available for 18 chronic pain populations (n = 484) and 15 control populations (n = 378). Our results suggest that tactile acuity is diminished in arthritis, complex regional pain syndrome, and chronic low back pain but not in burning mouth syndrome. The strength of the available evidence is weakened by somewhat inconsistent results and the high risk of bias observed in all of the included studies. PERSPECTIVE This systematic review synthesizes the evidence for tactile acuity deficits in people with chronic non-neuropathic pain. The findings suggest that tactile acuity deficits may be characteristic of chronic pain. That tactile acuity training may benefit those with chronic pain disorders suggests that clinical trials may be warranted.

Assessing tactile acuity in rheumatology and musculoskeletal medicine—how reliable are two-point discrimination tests at the neck, hand, back and foot?

OBJECTIVE Chronic pain from rheumatic and musculoskeletal conditions is associated with cortical changes and altered tactile acuity. Tactile acuity is considered a clinical signature of primary somatosensory representation. The two-point discrimination (TPD) threshold is increasingly used both clinically and in research. Remarkably, the reliability and precision of the measure at commonly used sites has not been determined. This study aimed to determine the utility, intra- and inter-rater reliability, bias and variability of TPD threshold assessment at the neck, back, hand and foot using mechanical callipers. METHODS Intra- and inter-rater reliability of TPD was assessed at the back, neck, hand and foot of 28 healthy young adults by 28 clinicians. Each clinician received training in the assessment of TPD using mechanical callipers and following a standardized protocol. Intraclass correlation coefficients (ICCs) and Bland-Altman plots were used to assess reliability, bias and variability. RESULTS Intra-rater assessments in all four regions and inter-rater assessments at the neck and foot were reliable (ICC range 0.79-0.86), but large variability was seen in all assessments. Inter-rater assessment of the back (ICC = 0.66) and hand (ICC = 0.62) was deemed unreliable. Negligible systematic bias suggested learning did not affect reliability. CONCLUSION Individual clinicians are able to reliably assess TPD threshold at the neck, back, hand and foot using mechanical callipers. Measures obtained by different clinicians were only reliable for the neck and foot. Large variability was observed in all assessments, which suggests clinicians should be cautious when interpreting changes in tactile acuity in individual patients.

How good is the neurophysiology of pain questionnaire? A Rasch analysis of psychometric properties.

UNLABELLED The Neurophysiology of Pain Questionnaire (NPQ) was devised to assess how an individual conceptualizes the biological mechanisms that underpin his or her pain. Despite its widespread use, its psychometric properties have not been comprehensively interrogated. Rasch analysis was undertaken on NPQ data from a convenience sample of 300 spinal pain patients, and test-retest reliability was assessed in a sample of 45 low back pain patients. The NPQ effectively targeted the ability of the sample and had acceptable internal consistency and test-retest reliability. However, some items functioned erratically for persons of differing abilities or were psychometrically redundant. The NPQ was reanalyzed with 7 questionable items excluded, and superior psychometric properties were observed. These findings suggest that the NPQ could be improved, but future prospective studies including qualitative measures are needed. In summary, the NPQ is a useful tool for assessing a patients conceptualization of the biological mechanisms that underpin his or her pain and for evaluating the effects of cognitive interventions in clinical practice and research. These findings suggest that it has adequate psychometric properties for use with chronic spinal pain patients. PERSPECTIVE Rasch analysis was used to analyze the NPQ. Despite several limitations, these results suggest that it is a useful tool with which to assess a patients conceptualization of the biological mechanisms that underpin his or her pain and to evaluate the effects of cognitive interventions in clinical practice and research.

Acupuncture applied as a sensory discrimination training tool decreases movement-related pain in patients with chronic low back pain more than acupuncture alone: a randomised cross-over experiment

Background High-quality clinical evidence suggests that although acupuncture appears superior to usual care in the management of chronic low back pain, there is little meaningful difference between true and sham acupuncture. This suggests that the benefits of acupuncture are mediated by the placebo response. An alternative explanation is that sham acupuncture is an active treatment and shares a mechanism of action with traditionally applied acupuncture. One plausible candidate for this mechanism is improvement in self-perception mediated through the sensory discrimination-like qualities of acupuncture. We aimed to compare the effects of acupuncture with a sensory discrimination training component to acupuncture without. Methods 25 people with chronic low back pain were enroled in a randomised cross-over experiment. We compared the effect of acupuncture delivered when sensory discrimination is optimised to acupuncture delivered when it is not, on movement-related back pain immediately after each intervention. Results We found that the average pain intensity after participants had received acupuncture with sensory discrimination training (2.8±2.5) was less than when they received acupuncture without sensory discrimination training (3.6±2.0). This difference was statistically significant (after adjustment; mean difference=−0.8, 95% CI −1.4 to −0.3; p=0.011). Conclusions Our findings are consistent with the idea that acupuncture may offer specific benefit that is not dependent on precisely where the needles are inserted so much as that the patient attends to where they are inserted. If so, the location of the needles might be better focused on the painful area and the need for penetration of the skin may be mitigated.

Rasch Analysis Supports the Use of the Pain Self-Efficacy Questionnaire

Background The Pain Self-Efficacy Questionnaire (PSEQ) is used by physical therapists in clinical practice and in research. However, current understanding of the PSEQs measurement properties is incomplete, and investigators cannot be confident that it provides unbiased information on patient self-efficacy. Objective The aims of this study were: (1) to investigate the scale properties of the PSEQ using Rasch analysis and (2) to determine whether age, sex, pain intensity, pain duration, and pain-related disability bias function of the PSEQ. Design This was a retrospective study; data were obtained from 3 existing studies. Methods Data were combined from more than 600 patients with low back pain of varying duration. Rasch analysis was used to evaluate targeting, category ordering, unidimensionality, person fit, internal consistency, and item bias. Results There was evidence of adequate category ordering, unidimensionality, and internal consistency of the PSEQ. Importantly, there was no evidence of item bias. Limitations The PSEQ did not adequately target the sample; instead, it targeted people with lower self-efficacy than this population. Item 7 was hardest for participants to endorse, showing excessive positive misfit to the Rasch model. Response strings of misfitting persons revealed older participants and those reporting high levels of disability. Conclusions The individual items of the PSEQ can be validly summed to provide a score of self-efficacy that is robust to age, sex, pain intensity, pain duration, and disability. Although item 7 is the most problematic, it may provide important clinical information and requires further investigation before its exclusion. Although the PSEQ is commonly used with people with low back pain, of whom the sample in this study was representative, the results suggest it targets patients with lower self-efficacy than that observed in the current sample.

Neural representations and the cortical body matrix: implications for sports medicine and future directions

Neural representations, or neurotags, refer to the idea that networks of brain cells, distributed across multiple brain areas, work in synergy to produce outputs. The brain can be considered then, a complex array of neurotags, each influencing and being influenced by each other. The output of some neurotags act on other systems, for example, movement, or on consciousness, for example, pain. This concept of neurotags has sparked a new body of research into pain and rehabilitation. We draw on this research and the concept of a cortical body matrix—a network of representations that subserves the regulation and protection of the body and the space around it—to suggest important implications for rehabilitation of sports injury and for sports performance. Protective behaviours associated with pain have been reinterpreted in light of these conceptual models. With a particular focus on rehabilitation of the injured athlete, this review presents the theoretical underpinnings of the cortical body matrix and its application within the sporting context. Therapeutic approaches based on these ideas are discussed and the efficacy of the most tested approaches is addressed. By integrating current thought in pain and cognitive neuroscience related to sports rehabilitation, recommendations for clinical practice and future research are suggested.

The close proximity of threat: altered distance perception in the anticipation of pain

Pain is an experience that powerfully influences the way we interact with our environment. What is less clear is the influence that pain has on the way we perceive our environment. We investigated the effect that the anticipation of experimental pain (THREAT) and its relief (RELIEF) has on the visual perception of space. Eighteen (11F) healthy volunteers estimated the distance to alternating THREAT and RELIEF stimuli that were placed within reachable space. The results determined that the estimated distance to the THREAT stimulus was significantly underestimated in comparison to the RELIEF stimulus. We conclude that pain-evoking stimuli are perceived as closer to the body than otherwise identical pain-relieving stimuli, an important consideration when applied to our decisions and behaviors in relation to the experience of pain.

Perceptual bias in pain: A switch looks closer when it will relieve pain than when it won’t

Summary Pain alters the way the environment is perceived. A pain‐relieving switch looks closer when you are experiencing pain than when you are not. Abstract Pain is fundamental to survival, as are our perceptions of the environment. It is often assumed that we see our world as a read‐out of the sensory information that we receive; yet despite the same physical makeup of our surroundings, individuals perceive differently. What if we “see” our world differently when we experience pain? Until now, the causal effect of experimental pain on the perception of an external stimulus has not been investigated. Eighteen (11 female) healthy volunteers participated in this randomised repeated‐measures experiment, in which participants estimated the distance to a switch placed on the table in front of them. We varied whether or not the switch would instantly stop a stimulus, set to the participant’s pain threshold, being delivered to their hand, and whether or not they were required to reach for the switch. The critical result was a strong interaction between reaching and pain [F(1, 181) = 4.8, P = 0.03], such that when participants experienced pain and were required to reach for a switch that would turn off the experimental stimulus, they judged the distance to that switch to be closer, as compared to the other 3 conditions (mean of the true distance 92.6%, 95% confidence interval 89.7%–95.6%). The judged distance was smaller than estimates in the other 3 conditions (mean ± SD difference >5.7% ± 2.1%, t(181) >3.5, P < 0.01 for all 3 comparisons). We conclude that the perception of distance to an object is modulated by the behavioural relevance of the object to ongoing pain.

Development and psychometric properties of knee-specific body-perception questionnaire in people with knee osteoarthritis: The Fremantle Knee Awareness Questionnaire

Background Recent systematic reviews have demonstrated that pain associated with knee osteoarthritis (OA) is a complex phenomenon that involves various contributors. People with knee OA exhibit symptoms of impaired body-perception, including reduced tactile acuity, impairments in limb laterality recognition, and degraded proprioceptive acuity. The Fremantle Back Awareness Questionnaire (FreBAQ) was developed to assess body-perception specific to the back in people with chronic low back pain. The aim of this study was to develop and assess the psychometric properties of a knee-specific version of the FreBAQ-J (FreKAQ-J), determine whether people with knee pain experience perceptual impairments and investigate the relationship between disturbed self-perception and clinical status. Methods Sixty-five people with knee OA completed the FreKAQ-J. A subset of the participants completed the FreKAQ-J again two-weeks later. Rasch analysis was used to assess item order, targeting, category ordering, unidimensionality, person fit, internal consistency, and differential item functioning. Validity was investigated by examining the relationship between the FreKAQ-J and clinical valuables. Results The FreKAQ-J had acceptable internal consistency, unidimensionality, good test-retest reliability, and was functional on the category rating scale. The FreKAQ-J was significantly correlated with pain in motion, disability, pain-related catastrophizing, fear of movement, and anxiety symptomatology. Conclusions We developed FreKAQ-J by modifying the FreBAQ-J. The FreKAQ-J fits the Rasch measurement model well and is suitable for use in people with knee OA. Altered body perception may be worth evaluating when managing people with knee OA.