The effect of contact/collision sport participation without concussion on neurometabolites: A systematic review and meta-analysis of magnetic resonance spectroscopy studies.

The aim of this study was to systematically review prior research investigating the effects of contact/collision sport participation on neurometabolite levels in the absence of concussion. Four online databases were searched to identify studies that measured neurometabolite levels in contact/collision sport athletes (without concussion) using proton (1 H) or phosphorus (31 P) magnetic resonance spectroscopy (MRS). All study designs were acceptable for inclusion. Meta-analytic procedures were used to quantify the effect of contact/collision sport participation on neurometabolite levels and explore the impact of specific moderating factors (where sufficient data were available). Narrative synthesis was used to describe outcomes that could not be meta-analysed. Nine observational studies involving 300 contact/collision sport athletes were identified. Six studies (providing 112 effect estimates) employed longitudinal (cohort) designs and three (that could not be meta-analysed) employed case-control designs. N-acetylaspartate (NAA; g = -0.331, p = 0.013) and total creatine (tCr; creatine + phosphocreatine; g = -0.524, p = 0.029), but not glutamate-glutamine (Glx), myo-inositol (mI) or total choline (tCho; choline-containing compounds; p's > 0.05), decreased between the pre-season and mid-/post-season period. Several moderators were statistically significant, including: sex (Glx: 6 female/23 male, g = -0.549, p = 0.013), sport played (Glx: 22 American football/4 association football [soccer], g = 0.724, p = 0.031), brain region (mI: 2 corpus callosum/9 motor cortex, g = -0.804, p = 0.015), and the MRS quantification approach (mI: 18 absolute/3 tCr-referenced, g = 0.619, p = 0.003; and tCho: 18 absolute/3 tCr-referenced, g = 0.554, p = 0.005). In case-control studies, contact/collision sport athletes had higher levels of mI, but not NAA or tCr compared to non-contact sport athletes and non-athlete controls. Overall, this review suggests that contact/collision sport participation has the potential to alter neurometabolites measured via 1 H MRS in the absence of concussion. However, further research employing more rigorous and consistent methodologies (e.g. interventional studies with consistent 1 H MRS pulse sequences and quantifications) is required to confirm and better understand the clinical relevance of observed effects.

Increase in ACC GABA+ levels correlate with decrease in migraine frequency, intensity and disability over time.

BACKGROUND: An imbalance between inhibitory and excitatory neurometabolites has been implicated in chronic pain. Prior work identified elevated levels of Gamma-aminobutyric acid + macromolecules ("GABA+") using magnetic resonance spectroscopy (MRS) in people with migraine. What is not understood is whether this increase in GABA+ is a cause, or consequence of living with, chronic migraine. Therefore, to further elucidate the nature of the elevated GABA+ levels reported in migraine, this study aimed to observe how GABA+ levels change in response to changes in the clinical characteristics of migraine over time. METHODS: We observed people with chronic migraine (ICHD-3) over 3-months as their treatment was escalated in line with the Australian Pharmaceutical Benefits Scheme (PBS). Participants underwent an MRS scan and completed questionnaires regarding migraine frequency, intensity (HIT-6) and disability (WHODAS) at baseline and following the routine 3 months treatment escalation to provide the potential for some participants to recover. We were therefore able to monitor changes in brain neurochemistry as clinical characteristics potentially changed over time. RESULTS: The results, from 18 participants who completed both baseline and follow-up measures, demonstrated that improvements in migraine frequency, intensity and disability were associated with an increase in GABA+ levels in the anterior cingulate cortex (ACC); migraine frequency (r = - 0.51, p = 0.03), intensity (r = - 0.51, p = 0.03) and disability (r = - 0.53, p = 0.02). However, this was not seen in the posterior cingulate gyrus (PCG). An incidental observation found those who happened to have their treatment escalated with CGRP-monoclonal antibodies (CGRP-mAbs) (n = 10) had a greater increase in ACC GABA+ levels (mean difference 0.54 IU IQR [0.02 to 1.05], p = 0.05) and reduction in migraine frequency (mean difference 10.3 IQR [2.52 to 18.07], p = 0.01) compared to those who did not (n = 8). CONCLUSION: The correlation between an increase in ACC GABA+ levels with improvement in clinical characteristics of migraine, suggest previously reported elevated GABA+ levels may not be a cause of migraine, but a protective mechanism attempting to suppress further migraine attacks.

Increased GABA+ in People With Migraine, Headache, and Pain Conditions- A Potential Marker of Pain.

Treatment outcomes for migraine and other chronic headache and pain conditions typically demonstrate modest results. A greater understanding of underlying pain mechanisms may better inform treatments and improve outcomes. Increased GABA+ has been identified in recent studies of migraine, however, it is unclear if this is present in other headache, and pain conditions. We primarily investigated GABA+ levels in the posterior cingulate gyrus (PCG) of people with migraine, whiplash-headache and low back pain compared to age- and sex-matched controls, GABA+ levels in the anterior cingulate cortex (ACC) and thalamus formed secondary aims. Using a cross-sectional design, we studied people with migraine, whiplash-headache or low back pain (n = 56) and compared them with a pool of age- and sex-matched controls (n = 22). We used spectral-edited magnetic resonance spectroscopy at 3T (MEGA-PRESS) to determine levels of GABA+ in the PCG, ACC and thalamus. PCG GABA+ levels were significantly higher in people with migraine and low back pain compared with controls (eg, migraine 4.89 IU ± 0.62 vs controls 4.62 IU ± 0.38; P = .02). Higher GABA+ levels in the PCG were not unique to migraine and could reflect a mechanism of chronic pain in general. A better understanding of pain at a neurochemical level informs the development of treatments that target aberrant brain neurochemistry to improve patient outcomes. PERSPECTIVE: This study provides insights into the underlying mechanisms of chronic pain. Higher levels of GABA+ in the PCG may reflect an underlying mechanism of chronic headache and pain conditions. This knowledge may help improve patient outcomes through developing treatments that specifically address this aberrant brain neurochemistry.

Minimum Reporting Standards for in vivo Magnetic Resonance Spectroscopy (MRSinMRS): Experts' consensus recommendations.

The translation of MRS to clinical practice has been impeded by the lack of technical standardization. There are multiple methods of acquisition, post-processing, and analysis whose details greatly impact the interpretation of the results. These details are often not fully reported, making it difficult to assess MRS studies on a standardized basis. This hampers the reviewing of manuscripts, limits the reproducibility of study results, and complicates meta-analysis of the literature. In this paper a consensus group of MRS experts provides minimum guidelines for the reporting of MRS methods and results, including the standardized description of MRS hardware, data acquisition, analysis, and quality assessment. This consensus statement describes each of these requirements in detail and includes a checklist to assist authors and journal reviewers and to provide a practical way for journal editors to ensure that MRS studies are reported in full.

The effectiveness of hip arthroscopic surgery for the treatment of femoroacetabular impingement syndrome: A systematic review and meta-analysis.

OBJECTIVE: To determine the effectiveness of hip arthroscopic surgery for the treatment of femoroacetabular impingement syndrome (FAI). DESIGN: Systematic review with meta-analysis. DATA SOURCES: We performed electronic database searches in MEDLINE, Embase, SPORTDiscus, CINAHL, Cochrane Central Register for Controlled Trials (CENTRAL), Web of Science, Scopus, the WHO International Clinical Trials Registry Platform and ClinicalTrials.gov from their inception to July 10th 2019. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: We included randomised controlled trials (RCTs) comparing hip arthroscopic surgery to a placebo/sham surgery and other non-operative comparators (e.g. no intervention, physiotherapy, etc.). Two authors independently selected studies, rated risk of bias, extracted data, and judged overall certainty of evidence using GRADE. Hip-specific quality of life (QoL) at 12 months was the primary outcome. RESULTS: We identified three RCTs (n = 650 participants). There is high certainty evidence from three RCTs (n = 574 participants) that hip arthroscopic surgery provided superior outcomes compared to non-operative care for hip-specific QoL at 12 months (mean difference (MD): 11.02 points, 95% CI 4.83-17.21). Low quality evidence suggests that arthroscopic surgery provided similar outcomes to non-operative care for hip-specific QoL at 24 months (MD: 6.3, 95% CI -6.1 to 18.7). CONCLUSION: Hip arthroscopic surgery for FAI provides superior outcomes compared to non-operative care at 12 months, but not at 24 months. Placebo trials are needed to establish the efficacy of hip arthroscopic surgery.

Implicit motor imagery performance is impaired in people with chronic, but not acute, neck pain.

BACKGROUND: People with chronic neck pain have impaired proprioception (i.e., sense of neck position). It is unclear whether this impairment involves disruptions to the proprioceptive representation in the brain, peripheral factors, or both. Implicit motor imagery tasks, namely left/right judgements of body parts, assess the integrity of the proprioceptive represention. Previous studies evaluating left/right neck judgements in people with neck pain are conflicting. We conducted a large online study to comprehensively address whether people with neck pain have altered implicit motor imagery performance. METHODS: People with and without neck pain completed online left/right neck judgement tasks followed by a left/right hand judgement task (control). Participants judged whether the person in the image had their head rotated to their left or right side (neck task) or whether the image was of a left hand or a right hand (hand task). Participants were grouped on neck pain status (no pain; <3 months-acute; ≥3 months-chronic) and pain location (none, left-sided, right-sided, bilateral). Outcomes included accuracy (primary) and response time (RT; secondary). Our hypotheses-that (i) chronic neck pain is associated with disrupted performance for neck images and (ii) the disruption is dependent on the side of usual pain, were tested with separate ANOVAs. RESULTS: A total of 1,404 participants were recruited: 105 reported acute neck pain and 161 reported chronic neck pain. When grouped on neck pain status, people with chronic neck pain were less accurate than people without neck pain (p = 0.001) for left/right neck judgements, but those with acute neck pain did not differ from those without neck pain (p = 0.14) or with chronic neck pain (p = 0.28). Accuracy of left/right hand judgements did not differ between groups (p = 0.58). RTs did not differ between groups for any comparison. When grouped on neck pain location, people were faster and more accurate at identifying right-turning neck images than left-turning neck images, regardless of history or location of pain (p < 0.001 for both); people with no pain were more accurate and faster than people with bilateral neck pain (p = 0.001, p = 0.015) and were faster than those with left-sided neck pain (p = 0.021); people with right-sided neck pain were more accurate than people with bilateral neck pain (p = 0.018). Lastly, there was a significant interaction between neck image and side of neck pain: people with right-sided neck pain were more accurate at identifying right-sided neck turning images than people with left-sided neck pain (p = 0.008), but no different for left-sided neck turning images (p = 0.62). CONCLUSIONS: There is evidence of impaired implicit motor imagery performance in people with chronic neck pain, which may suggest disruptions to proprioceptive representation of the neck. These disruptions seem specific to the neck (performance on hand images intact) but non-specific to the exact location of neck pain.

Physiotherapists' views on the Australian Physiotherapy Association's Choosing Wisely recommendations: a content analysis.

OBJECTIVES: Choosing Wisely holds promise for increasing awareness of low-value care in physiotherapy. However, it is unclear how physiotherapists' view Choosing Wisely recommendations. The aim of this study was to evaluate physiotherapists' feedback on Choosing Wisely recommendations and investigate agreement with each recommendation. SETTING: The Australian Physiotherapy Association emailed a survey to all 20 029 physiotherapist members in 2015 seeking feedback on a list of Choosing Wisely recommendations. PARTICIPANTS: A total of 9764 physiotherapists opened the email invitation (49%) and 543 completed the survey (response rate 5.6%). Participants were asked about the acceptability of the wording of recommendations using a closed (Yes/No) and free-text response option (section 1). Then using a similar response format, participants were asked whether they agreed with each Choosing Wisely recommendation (sections 2-6). PRIMARY AND SECONDARY OUTCOMES: We performed a content analysis of free-text responses (primary outcome) and used descriptive statistics to report agreement and disagreement with each recommendation (secondary outcome). RESULTS: There were 872 free-text responses across the six sections. A total of 347 physiotherapists (63.9%) agreed with the 'don't' style of wording. Agreement with recommendations ranged from 52.3% (electrotherapy for back pain) to 76.6% (validated decision rules for imaging). The content analysis revealed that physiotherapists felt that blanket rules were inappropriate (range across recommendations: 13.9%-30.1% of responses), clinical experience is more valuable than evidence (11.7%-28.3%) and recommendations would benefit from further refining or better defining key terms (7.3%-22.4%). CONCLUSIONS: Although most physiotherapists agreed with both the style of wording for Choosing Wisely recommendations and with the recommendations, their feedback highlighted a number of areas of disagreement and suggestions for improvement. These findings will support the development of future recommendations and are the first step towards increasing the impact Choosing Wisely has on physiotherapy practice.

Thoracic manual therapy in the management of non-specific shoulder pain: a systematic review.

OBJECTIVES: Non-specific shoulder pain (NSSP) is often persistent and disabling leading to high socioeconomic costs. Cervical manipulation has demonstrated improvements in patients with NSSP, although risks associated with thrust techniques are documented. Thoracic manual therapy (TMT) may utilise similar neurophysiological effects with less risk. The current evidence for TMT in treating NSSP is limited to systematic reviews of manual therapy (MT) applied to the upper quadrant. These reviews included trials that used shoulder girdle manual therapy (SG-MT) in the TMT group. This limits the scope of their conclusions with regard to the exclusive effectiveness of TMT for NSSP. METHODS: This review used a steering group for subject and methodological expertise and was reported in line with Preferred Reporting items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Key databases were searched (1990-2014) using relevant search terms and medical subject headings (MeSH); eligibility was evaluated independently by two reviewers based on pre-defined criteria. Study participants had NSSP including impingement syndrome and excluding cervical pain. Interventions included cervicothoracic junction and TMT with or without supplementary exercises. Studies that included MT applied to the shoulder girdle including the glenohumeral joint, acromioclavicular joint or sternoclavicular joint in the TMT group, without a control, were excluded. Included studies utilised outcome measures that monitored pain and disability scores. Randomized controlled trials (RCTs) and clinical studies were eligible. Using a standardised form, each reviewer independently extracted data. Risk of bias was assessed using GRADE and PEDro scale. Results were tabulated for semi-quantitative comparison. RESULTS: Over 912 articles were retrieved: three RCTs, one single-arm trial and three pre-post test studies were eligible. Studies varied from poor to high quality. Three RCTs demonstrated that TMT reduced pain and disability at 6, 26 and 52 weeks compared with usual care. Two pre-post test studies found between 76% and 100% of patients experienced significant pain reduction immediately post-TMT. An additional pre-post test study and a single-arm trial showed reductions in pain and disability scores 48 hours post-TMT. DISCUSSION: Thoracic manual therapy accelerated recovery and reduced pain and disability immediately and for up to 52 weeks compared with usual care for NSSP. Further, high-quality RCTs investigating the effect of TMT in isolation for the treatment of patients with NSSP are now required.