Dyspnea is an under‐recognized and debilitating symptom that is reported in up to 40% of patients with Parkinson's disease and may have multiple origins. Despite its frequency, it is poorly researched, and there is a general lack of understanding of the pathophysiology of dyspnea and respiratory dysfunction in PD. Consequently, a number of PD patients are labelled as having “unexplained dyspnea.” Studies to date have focused mainly on evaluating ventilatory capacity and lung volumes, and little is known about the effects of the disease on the medullary and pontine ventilatory control centers within the brainstem. This is of particular relevance in view of neuropathological studies demonstrating early involvement of the dorsal medulla and other brainstem structures by the disease process. The possibility that impaired brainstem ventilatory control is a contributory mechanism for dyspnea and could be a premotor manifestation in some PD patients therefore warrants further attention. This review focuses on clinical, pathological, and experimental evidence for the involvement of brainstem respiratory centers in PD. We highlight the need for further research, particularly in PD patients with unexplained dyspnea. © 2019 International Parkinson and Movement Disorder Society

This statement summarises and appraises the evidence on diagnosis, prevention and treatment of the most common lower extremity muscle injuries in sport. We systematically searched electronic databases, and included studies based on the highest available evidence. Subsequently, we evaluated the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation framework, grading the quality of evidence from high to very low. Most clinical tests showed very low to low diagnostic effectiveness. For hamstring injury prevention, programmes that included the Nordic hamstring exercise resulted in a hamstring injury risk reduction when compared with usual care (medium to large effect size; moderate to high quality of evidence). For prevention of groin injuries, both the FIFA 11+programme and the Copenhagen adductor strengthening programme resulted in a groin injury risk reduction compared with usual care (medium effect size; low to moderate quality of evidence). For the treatment of hamstring injuries, lengthening hamstring exercises showed the fastest return to play with a lower reinjury rate compared with conventional hamstring exercises (large effect size; very low to low quality of evidence). Platelet-rich plasma had no effect on time to return-to-play and reinjury risk (trivial effect size; moderate quality of evidence) after a hamstring injury compared with placebo or rehabilitation. At this point, most outcomes for diagnosis, prevention and treatment were graded as very low to moderate quality of evidence, indicating that further high-quality research is likely to have an important impact on the confidence in the effect estimates.

Background Concussion is the most common injury in youth ice hockey. Whether mouthguard use lowers the odds of concussion remains an unanswered question. Objective To determine the association between concussion and mouthguard use in youth ice hockey. Methods Nested case–control design. Cases and controls were identified from two prospective cohort studies using valid injury surveillance methods. Cases were players concussed during a game or practice; controls were players who sustained a non-concussion injury during a game or practice. The primary exposure was mouthguard use at time of injury; mouthguard type (dental custom fit or off the shelf) was a secondary exposure. Physician-diagnosed or therapist-suspected concussion was the primary outcome. Dental injury was a secondary outcome. Multilevel logistic regression with random effect at a team level was used to obtain ORs for the mouthguard effect, adjusted for level of play, age group, position, concussion history, mechanism of injury, cohort, session type and body checking policy. Results Among cases, 236/315 (75%) were wearing a mouthguard at time of injury, while 224/270 (83%) controls were wearing a mouthguard at time of injury. Any mouthguard use was associated with an adjusted OR for concussion of 0.36 (95% CI 0.17 to 0.73). Off-the-shelf mouthguards were associated with a 69% lower odds of concussion (adjusted OR: 0.31; 95% CI 0.14 to 0.65). Dental custom-fit mouthguards were associated with a non-significant 49% lower odds of concussion (adjusted OR: 0.51; 95% CI 0.22 to 1.10). No dental injuries were identified in either cohort. Conclusion Mouthguard use was associated with lower odds of concussion. Players should be required to wear mouthguards in youth ice hockey.

The WHO Global Action Plan on Physical Activity (GAPPA) (#GAPPA)1 highlights the importance of a systems-wide approach to achieving the global goals for reducing physical inactivity at the national, community, individual and patient levels. Within this scope, objective 1.4 of that plan details the vision and strategy for capacity planning for the health workforce and the collaborations required for success. This objective is closely linked to existing global and national efforts to enable the future healthcare professional (HCP) workforce to have the capability and competencies to make every contact count for physical activity support and advice (via brief interventions). A significant part of these goals is to enable the future and current healthcare workforce to meet the challenges of non-communicable diseases (NCDs), sustainable development goals (SDGs) and person-centred healthcare, exemplars of which have been identified in most European countries.2 3 Indeed, a physical activity resource focused approach in undergraduate healthcare courses such as medicine, nursing and allied health is critical in higher education institutes’ (HEIs) strategies2 4 5 to deliver on these directives. Reaching the potential of knowledge and skill acquisition in physical activity interventions is a challenge in practice.6–8 Yet we know that HCP practice influences healthcare behaviours in patients: this is the basis of ‘making every contact count’ …

Objective To characterise whether preseason screening of shoulder range of motion (ROM) is associated with the risk of shoulder and elbow injuries in overhead athletes. Design Systematic review and meta-analysis. Data sources Six electronic databases up to 22 September 2018. Eligibility criteria Inclusion criteria were (1) overhead athletes from Olympic or college sports, (2) preseason measures of shoulder ROM, (3) tracked in-season injuries at the shoulder and elbow, and (4) prospective cohort design. Exclusion criteria were (1) included contact injuries, (2) lower extremity, spine and hand injuries, and (3) full report not published in English. Results Fifteen studies were identified, and they included 3314 overhead athletes (baseball (74.6%), softball (3.1%), handball (16.1%), tennis (2.0%), volleyball (2.0%) and swimming (2.2%)). Female athletes are unrepresented (12% of the overall sample). Study quality ranged from 11 to 18 points on a modified Downs and Black checklist (maximum score 21, better quality). In one study, swimmers with low (<93°) or high (>100°) shoulder external rotation were at higher risk of injuries. Using data pooled from three studies of professional baseball pitchers, we showed in the meta-analysis that shoulder external rotation insufficiency (throwing arm <5° greater than the non-throwing arm) was associated with injury (odds ratio=1.90, 95% confidence interval 1.24 to 2.92, p<0.01). Conclusion Preseason screening of shoulder external rotation ROM may identify professional baseball pitchers and swimmers at risk of injury. Shoulder ROM screening may not be effective to identify handball, softball, volleyball and tennis players at risk of injuries. The results of this systematic review and meta-analysis should be interpreted with caution due to the limited number of studies and their high degree of heterogeneity. PROSPERO registration number CRD42017072895.

Objective Determine whether impairments in lower limb muscle strength exist in individuals with chronic ankle instability (CAI) compared with uninjured controls. Design Systematic review with meta-analysis. Data source A comprehensive search of PubMed, Cochrane, CINAHL, Web of Science and EMBASE electronic databases from inception to 10 February 2019. Eligibility criteria for selecting studies Cross-sectional and case–control studies were included if they objectively measured lower limb muscle strength in individuals with CAI compared with controls. Risk of bias and quality of included studies were assessed. Data of included studies were extracted, and meta-analysis was conducted where appropriate. Results 12 397 unique studies were identified, of which 20 were included and 16 were eligible for meta-analysis. Reviewed studies clearly described the aim/hypothesis and main outcome measure, but most lacked sample size calculation and assessor blinding. Meta-analyses showed individuals with CAI had lower eccentric and concentric evertor strength (30 and 120°/s; Nm; standardised mean difference (SMD) between −0.73 and −0.95), eccentric invertor strength (60 and 120°/s; both Nm and Nm/kg; SMD between −0.61 and −1.37), concentric invertor strength (60 and 120°/s; Nm; SMD=−0.7) and concentric knee extensor strength (SMD=−0.64) compared with control participants. Ankle eccentric dorsiflexor strength was not different between groups. Although pooling was not possible, data from three separate studies indicated that hip flexor, abductor and external rotator strength, but not hip adductor and extensor strength, was lower in individuals with CAI than in control participants. Conclusion Individuals with CAI have ankle inversion and eversion strength deficits. Our data also point to differences between individuals with CAI and controls in hip and knee strength. These elements of the kinetic chain should be evaluated by clinicians who rehabilitate individuals with CAI. PROSPERO registration number CRD42016037759.

Loss of skeletal muscle mass (SMM) increases the risk of frailty and, together with excess fat mass (FM), is a risk factor for cardio‐metabolic disease. However, use of body composition measurements in nutritional surveillance and routine clinical practice is limited by the lack of reference data. Our aim was to produce age‐specific and sex‐specific reference values for SMM and FM in the White ethnic adult population in the UK. Secondary objectives were to examine the tracking over time using a subsample of the population with repeated measures of body composition and to assess the validity of these reference values in different ethnic subgroups.

Alterations in sensory discrimination are a prominent nonmotor feature of dystonia. Abnormal temporal discrimination in focal dystonia is considered to represent its mediational endophenotype, albeit unclear pathophysiological correlates. We examined the associations between the visual temporal discrimination threshold (TDT) and brain activity in patients with musician's dystonia, nonmusician's dystonia, and healthy controls.

Apathy is one of the most disabling neuropsychiatric symptoms in Parkinson's disease (PD) patients and has a higher prevalence in patients under subthalamic nucleus deep brain stimulation. Indeed, despite its effectiveness for alleviating PD motor symptoms, its neuropsychiatric repercussions have not yet been fully uncovered. Because it can be alleviated by dopaminergic therapies, especially D2 and D3 dopaminergic receptor agonists, the commonest explanation proposed for apathy after subthalamic nucleus deep brain stimulation is a too‐strong reduction in dopaminergic treatments. The objective of this study was to determine whether subthalamic nucleus deep brain stimulation can induce apathetic behaviors, which remains an important matter of concern. We aimed to unambiguously address this question of the motivational effects of chronic subthalamic nucleus deep brain stimulation.

The glial cell line‐derived neurotrophic factor has a potent neuroprotective action on mesencephalic dopamine neurons, which are progressively lost in Parkinson's disease. Intrastriatal administration of this factor is a promising therapy for Parkinson's disease. Glial cell line‐derived neurotrophic factor is naturally produced in restricted cerebral regions, such as the striatum, septum, and thalamus; however, its effects in the adult brain remain under debate.

The C allele of the rs11136000 genetic variant of the clusterin gene has been associated with increased risk of Alzheimer's disease. However, a comprehensive characterization of the role of this genetic variant in early cognitive deterioration in PD is lacking.

Abstract Background The long-term risk from knee intra-articular (KIA) injections in professional athletes such as ex-footballers remains unknown. The use of KIA injections is controversial and remains anecdotally prolific as it is perceived as being safe/beneficial. The aim of this study was to determine the number, type and frequency KIA injections administered to retired professional footballers during their playing careers and the associations with post-career knee osteoarthritis (KOA). Methods This is a cross-sectional study involving a postal questionnaire (n = 1207) and subsequent knee radiographs in a random sample of questionnaire responders (n = 470). Footballers self-reported in the questionnaire whether they had received KIA injections and the estimated total number over the course of their playing career. Participant characteristics and football career-related details were also recorded. KOA was measured as self-reported knee pain (KP), total knee replacement (TKR) and radiographic KOA (RKOA). Results 44.5% of footballers had received at least one KIA injection (mean: 7.5; SD ± 11.2) during their professional career. 71% of knee injections were cortisone/corticosteroid based. Multivariate logistic regression, adjusting for age, body mass index (BMI) and significant knee injury identified that footballers with injections were two times more likely to have KP (OR 1.81, 95% CI 1.40–2.34) and TKR (OR 2.21, 95% CI 1.43–3.42) than those without injections. However, there was no association with RKOA (OR 1.30, 95% CI 0.85–2.01). Given, the association with KP and TKR, we found a significant dose–response relationship as the more injections a player received (by dose–response groups), the greater the risk of KP and TKR outcomes after adjustment for knee injury and other confounders (p for trend < 0.01). Conclusion On average, 8 KIA injections were given to the ex-footballers during their professional career. The most commonly administered injections were cortisone based. These injections associated with KP and TKR after they retired. The associations are independent of knee injuries and are dose dependent. The study suggests that there may have been excessive use of KIA injections to expedite return to play and this contributed to detrimental long-term outcomes such as KP and TKR post-retirement from professional football.

Some forms of movement disorders are characterized by task‐specific manifestations of symptoms. However, its underlying mechanisms are poorly understood. Here we addressed this issue through a novel motor adaptation experimental paradigm.

To determine the relationships between the motor phenotype and the presence of specific neuropsychiatric and neuropsychological disorders in patients with early motor‐manifest Huntington's disease (HD).

The group of dystonia genes is expanding, and mutations of these genes have been associated with various combined dystonia syndromes. Among the latter, the cause of some dystonia parkinsonism cases remains unknown.

Dysfunction of the mesencephalic locomotor region has been implicated in gait disorders. However, the role of its 2 components, the pedunculopontine and the cuneiform nuclei, in locomotion is poorly understood in primates.

Although deep brain stimulation of the globus pallidus internus (GPi‐DBS) is an established treatment for many forms of dystonia, including generalized as well as focal forms, its effects on brain (dys‐)function remain to be elucidated, particularly for focal and segmental dystonia. Clinical response to GPi‐DBS typically comes with some delay and lasts up to several days, sometimes even weeks, once stimulation is discontinued.

Sarcopenia, the unintentional loss of skeletal muscle mass, is associated with poor outcomes in adult patient populations. In adults, sarcopenia is often ascertained by cross‐sectional imaging of the psoas muscle area (PMA). Although children with chronic medical illnesses may be at increased risk for muscle loss because of nutritional deficiencies, physical deconditioning, endocrine anomalies, and systemic inflammation, consistent quantitative definitions for sarcopenia in children are lacking. We aimed to generate paediatric reference values for PMA at two intervertebral lumbar levels, L3–4 and L4–5.

Changing a sport system requires the appointment of new leaders or a grass roots cultural revolution. ‘I got caught in a system designed by and for men, which destroys the bodies of young girls,’ said Mary Cain as she cast light on her toxic coach/athlete relationship and exposed unhealthy coaching and nutrition practices. Her candour has inspired a social media movement calling for changes to women’s sport.1 In the following days, major news publications followed up with similar reports of athletic women being body shamed.2–4 It is time for a drastic paradigm change in women’s sport, coupled with education at all levels to improve the long-term health and athletic achievement of female athletes. The shift needs to include: 1. Raising awareness of the negative effects of chronic low energy availability (LEA) (calorie restriction) so athletes can make wise choices for their own long-term health. 2. Updating and developing best-practice protocols and safe standards for monitoring body composition/weight. 3. Eliminating toxic training environments featuring abusive body shaming. Overexercising or underfueling, occurring consciously or subconsciously, can cause Relative …

Many patients with cancer experience poor nutritional status, which detrimentally impacts clinical outcomes. Poor nutritional status in cancer is primarily manifested by severe muscle mass (MM) depletion, which may occur at any stage (from curative to palliative) and often co‐exists with obesity. The objective of this article was to discuss gaps and opportunities related to the role of nutrition in preventing and reversing low MM in cancer. It also provides a narrative review of relevant nutritional interventions for patients capable of oral intake. The impact of nutrition interventions to prevent/treat low MM in cancer is not well understood, potentially due to the limited number of studies and of clinically viable, accurate body composition assessment tools. Additionally, the type of study designs, inclusion criteria, length of intervention, and choice of nutritional strategies have not been optimal, likely underestimating the anabolic potential of nutrition interventions. Nutrition studies are also often of short duration, and interventions that adapt to the metabolic and behavioural changes during the clinical journey are needed. We discuss energy requirements (25–30 kcal/kg/day) and interventions of protein (1.0–1.5 g/kg/day), branched‐chain amino acids (leucine: 2–4 g/day), β‐hydroxy β‐methylbutyrate (3 g/day), glutamine (0.3 g/kg/day), carnitine (4–6 g/day), creatine (5 g/day), fish oil/eicosapentanoic acid (2.0–2.2 g/day EPA and 1.5 g/day DHA), vitamin/minerals (e.g. vitamin D: 600–800 international units per day), and multimodal approaches (nutrition, exercise, and pharmaceutical) to countermeasure low MM in cancer. Although the evidence is variable by modality type, interventions were generally not specifically studied in the context of cancer. Understanding patients' nutritional requirements could lead to targeted prescriptions to prevent or attenuate low MM in cancer, with the overall aim of minimizing muscle loss during anti‐cancer therapy and maximizing muscle anabolism during recovery. It is anticipated that this will, in turn, improve overall health and prognostication including tolerance to treatment and survival. However, oncology‐specific interventions with more robust study designs are needed to facilitate these goals.

Heterozygous mutations in the glucocerebrosidase gene (GBA) have been shown to be an important genetic risk factor for Parkinson's disease (PD) worldwide. However, the penetrance of GBA heterozygote for L444P, the common mutation for Asian population, is not known in older Chinese people.

Frail older adults are at increased risk of post‐operative morbidity compared with robust counterparts. Simple methods testing frailty such as grip strength or gait speed have shown promising results for predicting post‐operative outcome, but there is a debate regarding the most appropriate and precise frailty assessment method. We compared the predictive value of multidimensional frailty score (MFS) with grip strength, gait speed, or conventional risk stratification tool for predicting post‐operative complications in older surgical patients.

Hip fracture is both a cause and a consequence of sarcopenia. Older persons with sarcopenia have an increased risk of falling, and the prevalence of sarcopenia may be increased in those who suffer a hip fracture. The aim of this study was to explore potential biomarkers (neuromuscular and peripheral pro‐inflammatory and oxidative stress markers) that may be associated with sarcopenia in very old persons with hip fracture.

There has been limited longitudinal assessment of the relationship between moderate‐to‐vigorous physical activity (MVPA) and sedentary behaviour (SB) with frailty, and no studies have explored the possibility of reverse causality. This study aimed to determine the potential bidirectionality of the relationship between accelerometer‐assessed MVPA, SB, and frailty over time in older adults.

A proportion of TKA recipients following TKA are dissatisfied with their outcome. Our hypothesis is that patient satisfaction with TKA and perception of success of surgery are associated with patient comorbidities and overall health status, surgical and anaesthetic techniques as well as processes of post-operative care after TKA. The aims were to (i) measure the incidence of patient unfavourable outcomes—defined as dissatisfaction with the surgery or lack of joint-specific global improvement—1 year after TKA, and to explore the differences between these two outcomes of interest; (ii) assess the relationship between the development of these unfavourable outcomes and patient-reported knee function and overall quality of life; (iii) explore the associations between pre- and peri-operative variables and the development of these unfavourable outcomes 1 year after TKA.

Abstract Purpose There are a number of developments in intra-articular therapies that have been determined to be differentiating factors within the classes of treatments. This study evaluated the efficacy and safety of intra-articular treatments of primary knee osteoarthritis in the short term (3 months follow-up), using a network meta-analysis design, while taking within-class differentiating factors into consideration. Methods A literature search of MEDLINE (through OVID), EMBASE (through OVID), Cochrane Central Register of Controlled Trials for all trials comparing intra-articular therapies was conducted on November 12, 2018. The treatments assessed were high molecular weight and low molecular weight hyaluronic acid injections, extended-release corticosteroids, standard-release corticosteroids, platelet-rich plasma, and saline. A frequentist network meta-analysis was conducted for each outcome. Results Sixty-four articles (9710 patients) met the inclusion criteria. High molecular weight hyaluronic acid (− 0.53, 95% CI − 0.81 to − 0.25) and PRP (− 0.79, 95% CI − 1.32 to − 0.26) were the only treatments with a confidence interval that lay completely above the MID threshold; however, PRP results varied within sensitivity analyses. For the function analysis, high molecular weight hyaluronic acid (SMD − 0.76, 95% CI − 1.30 to − 0.22) was the only treatment with a confidence interval entirely above the MID. Extended-release corticosteroid demonstrated a possible benefit in functional improvement (SMD − 0.98, 95% CI − 1.79 to − 0.17) compared to that of standard-release corticosteroid (SMD − 0.14, 95% CI − 0.72 to 0.44). Conclusion High molecular weight HA was the only treatment to surpass the MID for both pain and function outcomes. Extended-release corticosteroids may provide additional clinical benefit over standard-release corticosteroids. Platelet-rich plasma demonstrated possibly beneficial results; however, wide confidence intervals and sensitivity analyses made the conclusions of efficacy uncertain. Level of evidence Level 1. Systematic review of level 1 evidence.

Abstract Purpose The aim of this study was to examine and evaluate the factors associated with changes in limb alignment 10 years after total knee arthroplasty (TKA). The hypothesis was that bone morphology and immediate postoperative alignment could be correlated with long-term post-operative alignment changes following TKA. Methods This study retrospectively analysed 136 consecutive primary TKA cases for varus deformity, performed from 2006 to 2008, that could be followed for at least 10 years postoperatively. Anteroposterior long-leg weight-bearing radiographs were obtained within 1 month and at least 10 years after surgery. The hip–knee–ankle (HKA) angle immediately after surgery was compared with that 10 years later; factors correlating with the change in HKA angle (δHKA) were evaluated. Results The mean HKA angles were significantly different between immediate and long-term postoperative assessments (0.1° ± 1.9° vs. 1.2° ± 2.9°, p < 0.001). Furthermore, a significant difference was observed in the outlier ratio (> 3° deviation from the 0° of HKA angle) (10% vs. 24%, p = 0.002). δHKA strongly correlated with a higher preoperative tibial plateau tip-to-proximal tibial shaft (TPTPS) angle, higher postoperative HKA angle, lateral distal femoral angle, and lower postoperative medial proximal tibial angle. Conclusion Varus deformity in the proximal part of the tibia, immediate postoperative varus alignment, and varus position of the femoral and tibial components may lead to varus progression in limb alignment in the long term, even 10 years after TKA; the surgeon should, therefore, weigh the risks of leaving a varus alignment during surgery. Moreover, if the preoperative TPTPS angle is high, the alignment may become varus after TKA, even in patients who have acquired neutral alignment. Level of evidence IV.

Abstract Purpose Voluntary femoro-tibial subluxation is a rare entity predominantly found in pretoddlers. It presents as a dynamic phenomenon with uni- or bilateral audible snapping of the knee, often in a context of fatigue or irritation at the end of the day. The aim of the study was to observe the evolution and recovery in these patients. Methods Ten children were included. Other causes of dislocating joints and pathologies with snapping of the lateral meniscus were excluded from this study. Six-week immobilisation with a splint at 70° of knee flexion was primarily recommended to all patients. Results The mean age at onset of symptoms was 10 months. Forty percent of the patients presented with bilateral symptoms. Clinically, four patients were hyperlax. In all patients, subluxations could be reproduced passively by rotating the foot externally and advancing the internal tibial plateau anteriorly. Three of the patients were treated with a dorsal splint and experienced significantly less or cessation of symptoms. Two patients underwent surgery, one for a concomitant anterior cruciate ligament (ACL) rupture and meniscus tear that worsened the symptoms, another for concomitant patella dislocation and a meniscus tear. One patient’s parents refused treatment and four patients experienced less symptoms at the time of consultation and were not immobilized. Except for the two patients undergoing surgeries, no sequelae were observed. In general, the symptoms got less frequent when the patient began to walk. Conclusion Voluntary femoro-tibial subluxation in children is a rare and benign condition that often resolves spontaneously without sequelae. The risk of meniscus tear should, however, be considered if subluxations do not cease. Level of evidence IV.

Abstract Purpose This meta-analysis was performed systematically to evaluate the efficacy of subacromial balloon spacers for patients with massive, irreparable rotator cuff tears. Methods Electronic databases, including Medline/PubMed, Embase and Cochrane Library, were systematically searched to identify studies evaluating the efficacy of subacromial spacers for patients with irreparable or massive rotator cuff tears. Meta-analyses were performed to pool the outcome estimates of interest, such as the total constant score (TCS) and its sub-score (pain, activities of daily living [ADL], range of motion [ROM], and strength), Oxford shoulder score (OSS), American Shoulder and Elbow Society scores (ASES) and numeric rating scale (NRS), as well as different outcomes at different time points in the follow-up period. Results Ten studies with a total of 261 patients involving 270 shoulders were deemed viable for inclusion in the meta-analysis. The combined results demonstrated significant improvements in the TCS at the final follow-up (pooled mean difference = 26.4, 95% confidence intervals [CIs] 23.3 to 29.5). A sensitivity analysis and subgroup analysis, which were implemented based on two factors, different follow-up points and sub-scores (pain, ADL, ROM, and strength), revealed a consistent trend. The combined shoulder motion results demonstrated significant improvements in the forward flexion and external rotation (0° abduction) variables rather than in the abduction and external rotation (90° abduction) variables. Additionally, significant improvements in the OSS and ASES and a decrease in the NRS were observed in the middle of the follow-up period. Conclusion This meta-analysis indicated that subacromial balloon spacer implantation for patients with massive irreparable rotator cuff tears may achieve satisfactory outcomes between 3 months and 3 years of follow-ups. Although the short- and middle- term effect is significant, the long-term effect needs to be confirmed by large-sample randomized controlled trial. Level of evidence IV.

Abstract Purpose Altered quadriceps muscle activity can contribute to reduced ability of the muscle to quickly generate force and appropriately attenuate landing forces, exacerbating poor landing and movement strategies commonly seen after anterior cruciate ligament reconstruction (ACLR). The purpose was to evaluate if electromyographic (EMG) activity and knee biomechanics during a single-limb forward hop task are influenced by a history of ACLR. Methods Twenty-six individuals with a history of unilateral ACLR (age 20.2 ± 2.7 years, height 1.7 ± 0.1 m; weight 69.6 ± 12.4 kg; time from surgery, 2.9 ± 2.7 years; graft type, 21 bone-patellar-tendon bone, 5 hamstring) and 8 healthy controls (age 23.3 ± 1.8 years, height 1.7 ± 0.1 m; mass 66.3 ± 13.9 kg) volunteered. Sagittal plane knee kinetics and EMG of the vastus lateralis were synchronized and measured using a three-dimensional motion analysis system during a single-limb forward hop task. Mixed-effect models were used to assess the effect of group on kinetic and EMG variables. Results Kinetic outcomes (peak and rate of knee extension moment) and temporal muscle activity and activation patterns differed between the ACLR limb and healthy-control limb. Inter-limb asymmetries in the ACLR group were observed for all variables except EMG onset time; no limb differences were observed in the healthy cohort. Conclusion Years after ACLR, persistent quadriceps functional deficits are present, contributing to altered neuromuscular control strategies during functional tasks that may increase the risk of reinjury. To counteract these effects, emerging evidence indicates that clinicians could consider the use of motor learning strategies to improve neuromuscular control after ACLR. Level of evidence III.

The aim of this study was to investigate the effect of product dose in autologous chondrocyte implantation (ACI) for the treatment of full-thickness cartilage defects of the knee and to assess its influence on clinical and morphological mid-term outcome.

To systematically analyse post-operative outcomes following enhanced microfracture procedures in focal cartilage injuries of the knee.

The aim of this study was to evaluate the union rate and risk factors for delayed union in the early postoperative period after an arthroscopic Latarjet with double-button fixation.

Abstract Purpose Fear of movement (kinesiophobia) is a major limiting factor in the return to pre-injury sport level after anterior cruciate ligament reconstruction (ACLR). The aim of this study was to gain insight into the prevalence of kinesiophobia pre-ACLR, 3 months post-ACLR and 12 months post-ACLR. Furthermore, the preoperative predictability of kinesiophobia at 3 months post-ACLR was addressed. Methods A retrospective study with data, which were prospectively collected as part of standard care, was conducted to evaluate patients who underwent ACLR between January 2017 and December 2018 in an orthopaedic outpatient clinic. Patient characteristics (age, sex, body mass index), injury-to-surgery time, preoperative pain level (KOOS pain subscale) and preoperative knee function (IKDC-2000) were used as potential predictor variables for kinesiophobia (TSK-17) at 3 months post-ACLR in linear regression analysis. Results The number of patients with a high level of kinesiophobia (TSK > 37) reduced from 92 patients (69.2%) preoperatively to 44 patients (43.1%) 3 months postoperatively and 36 patients (30.8%) 12 months postoperatively. The prediction model, based on a multivariable regression analysis, showed a positive correlation between four predictor variables (prolonged injury-to-surgery time, high preoperative pain level, male sex and low body mass index) and a high level of kinesiophobia at 3 months postoperatively (R2 = 0.384, p = 0.02). Conclusion The prevalence of kinesiophobia decreases during postoperative rehabilitation, but high kinesiophobia is still present in a large portion of the patients after ACLR. Timing of reconstruction seems to be the strongest predictor for high kinesiophobia 3 months post-ACLR. This study is the first step in the development of a screening tool to detect patients with kinesiophobia after ACLR. Identifying patients preoperatively opens the possibility to treat patients and thereby potentially increase the return to pre-injury sport level rate after ACLR. Level of evidence III.

Abstract Purpose To investigate the effect of proximal tibial tubercle osteotomy (PTO) and distal tibial tubercle osteotomy (DTO) in medial opening wedge high tibial osteotomy on patellofemoral alignment, patellofemoral osteoarthritis and clinical outcomes. Methods PTO (n = 41) and DTO (n = 43) for the same surgical indications were included. Radiographic measurements of the Caton-Deschamps index, patellar tilt and shift, and arthroscopic cartilage evaluation at the patellofemoral joint were performed at osteotomy and plate removal. The Knee Society Score (KSS) was evaluated preoperatively and at the latest follow-up. Results The follow-up period was longer in the PTO group (33.7 months; range 23–40 years) than in the DTO group (22.2 months; range 18–29 months) (p < 0.0001), whereas the period from osteotomy to plate removal was not different between the groups. The Caton-Deschamps index of the DTO group was unchanged from 0.9 (range 0.7–1.2) to 0.9 (range 0.6–1.4), whereas that of the PTO group changed from 0.9 (0.7–1.2) to 0.7 (0.5–1.0) (p < 0.0001). There were fewer deteriorated cases of cartilage status in the trochlear groove in the DTO group (20.9%) than in the PTO group (56.1%, p < 0.05). There were more improved cases in the DTO group (23.3%) than in the PTO group (4.9%, p < 0.05). Postoperative KSS was better in the DTO group than in the PTO group (p < 0.05). Conclusion DTO is associated not only with reduced deterioration but also with increased improvement of cartilage status in the trochlear groove and better KSS as compared with PTO. Level of evidence IV.

The current literature suggests that kinematic total knee arthroplasty (kTKA) may be associated with better outcome scores in patients with constitutional varus alignment. The underlying patellofemoral kinematic changes (patella tilting and patella tracking) and patellofemoral pressure distribution have not yet been described. The present study compared the effects of different tibial cuts, as used in kTKA, on patellofemoral knee kinematics and the pressure distribution, in addition to comparisons with the natural constitutional varus knee.

Abstract Purpose To test the hypothesis that an inclined articular surface on the medial proximal tibia is aligned more parallel to the ground in three-dimensional (3D) space under weight-bearing (WB) conditions (parallel phenomenon) than under non-WB (NWB) conditions in healthy and varus osteoarthritic knees. Methods We examined 55 healthy knees (26 women, 29 men; mean age, 70 ± 6 years) and 108 varus osteoarthritic knees (66 women, 16 men; mean age, 74 ± 7 years). For the evaluation under WB conditions, a 3D assessment system was used on biplanar long-leg radiographs and 3D bone models using a 3D-to-2D image registration technique. In addition, the least square method was used to determine the approximation plane. The angles between the normal vector for the approximation plane of an articular surface on the medial proximal tibia and each axis of the tibial or world coordinate system were calculated. Results Morphologically, the inclination of the approximation plane was steeper in osteoarthritic knees than in healthy knees (p < 0.0001). The approximation plane was aligned more parallel to the ground under WB conditions than under NWB conditions in healthy (p < 0.0001) and osteoarthritic knees (p < 0.0001). Conclusions The parallel phenomenon in the medial proximal tibia was confirmed for healthy and varus osteoarthritic knees. The medial proximal tibia plays an important role in the parallel phenomenon, assumingly associated with varus alignment and varus thrust. The inclination of the medial proximal tibia may become a new parameter for imaging investigations. Level of evidence III.

The purpose of this study was to compare the clinical results of the Latarjet procedure using two cortical buttons vs two screws. It was hypothesized that cortical button would result in similar rates of recurrent dislocations, but a lower rate of reoperation compared to screw fixation.

Abstract Purpose Previous cadaver studies showed that the additional bone cuts in the distal and posterior femur and joint line elevation resulted in laxity at mid-flexion after total knee arthroplasty (TKA). However, these results are not always applicable to TKA candidates because the related studies used cadaver knees with no osteoarthritis. It was hypothesized that the joint line elevation results in mid-flexion laxity after TKA in patients with knee osteoarthritis. The purpose of this study was to analyze the relationship between joint line elevation and mid-flexion laxity in patients with knee osteoarthritis. Methods 30 knees with varus osteoarthritis undergoing TKA were evaluated. Two femoral trial component models were prepared: (1) normal model with a thickness of the distal and posterior femoral components of 9 mm, and (2) 2-mm joint line elevation model with a thickness of the distal and posterior femoral components of 9 − 2 = 7 mm. This 2-mm joint line elevation model simulated an additional bone cut in the distal and posterior femur, and joint line elevation, without an additional bone cut. The femoral trial component models were set before implantation and measured the joint gap kinematics using a tensor device through the full knee range of motion. Results The differences in joint gap change from 30° to 90° were not statistically significant between the two models. However, the joint line elevation model decreased the joint gap laxity at 120° (p = 0.02) and at 145° (p = 0.01). Conclusions This study showed that a 2-mm joint line elevation was not associated with mid-flexion laxity in patients with varus osteoarthritis in the knee. The results of this study differed from the results in previous cadaver studies. Level of evidence Therapeutic study, level II, prospective comparative study.

The pivot shift (PS) test is commonly used to diagnose and evaluate the dynamic instability of the knee joint in cases of anterior cruciate ligament (ACL) tear. There is a need of a reliable and inexpensive tool which is easily available to measure PS objectively in a clinical setting. The purpose of this study was to evaluate the use of a smartphone, which is readily available, to assess the PS phenomenon.

Abstract Purpose Machine-learning methods are flexible prediction algorithms with potential advantages over conventional regression. This study aimed to use machine learning methods to predict post-total knee arthroplasty (TKA) walking limitation, and to compare their performance with that of logistic regression. Methods From the department’s clinical registry, a cohort of 4026 patients who underwent elective, primary TKA between July 2013 and July 2017 was identified. Candidate predictors included demographics and preoperative clinical, psychosocial, and outcome measures. The primary outcome was severe walking limitation at 6 months post-TKA, defined as a maximum walk time ≤ 15 min. Eight common regression (logistic, penalized logistic, and ordinal logistic with natural splines) and ensemble machine learning (random forest, extreme gradient boosting, and SuperLearner) methods were implemented to predict the probability of severe walking limitation. Models were compared on discrimination and calibration metrics. Results At 6 months post-TKA, 13% of patients had severe walking limitation. Machine learning and logistic regression models performed moderately [mean area under the ROC curves (AUC) 0.73–0.75]. Overall, the ordinal logistic regression model performed best while the SuperLearner performed best among machine learning methods, with negligible differences between them (Brier score difference, < 0.001; 95% CI [− 0.0025, 0.002]). Conclusions When predicting post-TKA physical function, several machine learning methods did not outperform logistic regression—in particular, ordinal logistic regression that does not assume linearity in its predictors. Level of evidence Prognostic level II

Abstract Purpose To assess the usefulness of a whole-leg radiograph standing on lateral-wedge insole (LWI) for predicting the change in joint line convergence angle (JLCA) before vs. after high tibial osteotomy (HTO). Methods Forty knees with medial osteoarthritis underwent open-wedge HTO. Pre-operatively, all patients had whole-leg radiographs taken in three different conditions: supine, standing, and standing on LWI inclined at 20°. A standing whole-leg radiograph was also obtained post-operatively. Radiological measurements including JLCA and percentage of mechanical axis (%MA) were compared. Using pre-operative radiographs, correction angles were calculated with the target %MA at 62.5%. Correlations between the difference in calculated correction angle among the three pre-operative conditions and the change in JLCA before vs. after HTO were assessed. Results In the pre-operative standing conditions, the mean JLCA of 3.8° was significantly decreased to 3.2° using LWI, which did not differ from post-operative JLCA of 3.1°. Mean %MA significantly shifted laterally from 20.6 to 24.8% using LWI, and was strongly correlated with the change in JLCA (coefficient, 0.83). Calculated correction angles differed significantly among the three pre-operative conditions. The difference in calculated correction angle between standing with and without LWI was strongly correlated to the change in standing JLCA before vs. after HTO (coefficient, 0.73). Conclusion Larger differences in calculated correction angles between pre-operative radiographs standing with and without LWI predicted larger changes in JLCA after HTO. Whole-leg radiograph standing on LWI is a promising modality for correct pre-operative planning considering patient-specific changes in JLCA before vs. after HTO. Level of evidence IV.

Given the increasing incidence of arthroscopic anterior cruciate ligament reconstruction (ACLR), mid- to long-term rates of reoperations were investigated on the ipsilateral knee following ACLR.

All physical activity (PA) behaviours undertaken over the day, including sleep, sedentary time, standing time, light-intensity PA (LIPA) and moderate-to-vigorous PA (MVPA) have the potential to influence cardiometabolic health. Since these behaviours are mutually exclusive, standard statistical approaches are unable to account for the impact on time spent in other behaviours.

Abstract Recent studies have concluded that athletes have increased risk of musculoskeletal injury following sport-related concussion. While an underlying explanation is still unknown, perceptual-motor control may be implicated in this increased risk. Some authors have purported that indirect perception (i.e., a “top-down” view of neuromuscular control) may be disrupted following sport-related concussion. Direct perception theory states that the athlete and environment are inextricably linked in a continuous perception–action coupling loop. That is, the athlete is able to directly perceive opportunities for action (e.g., “affordances”) in the environment. Based on these notions, the aim of the current paper was to introduce a theoretical model that argues that sport-related concussion may dysregulate the direct perception process, potentially increasing behavioral risk of musculoskeletal injury during sport. Our model is integrated with a sport-related concussion clinical treatment model, which highlights individualized profiles that characterize the heterogeneous response to sport-related concussion. These profiles have a typical constellation of symptoms (e.g., anxiety, fatigue, ocular dysfunction, etc.), which themselves have been associated with disrupted perception–action coupling, independent of sport-related concussion. Therefore, we argue that athletes who have not re-established perception–action coupling loops following sport-related concussion may be at increased risk of subsequent musculoskeletal injury.

PINK1 mutations are likely to affect mitochondrial function. The objective of this study was to study brain mitochondrial function in patients with early‐onset Parkinson's disease, with or without PINK1 mutations.

Reversible ε‐amino acetylation of lysine residues regulates transcription as well as metabolic flux; however, roles for specific lysine acetyltransferases in skeletal muscle physiology and function are unknown. In this study, we investigated the role of the related acetyltransferases p300 and cAMP response element‐binding protein‐binding protein (CBP) in skeletal muscle transcriptional homeostasis and physiology in adult mice.

My 9-year-old daughter woke up the morning after a long day of gymnastics training and complained that her muscle hurts. ‘I need a pill to stop the pain, NOW daddy’. Right, how do I deal with this one? Should I break out the pain education metaphors? Or give her a massage? Go for some contrast baths? I decided that the appropriate referral was a joint trip to the bakery. Over Finnish Pulla (cardamom sweet bread), we discussed that she had delayed-onset muscle soreness (DOMS), which is transient and not dangerous. During our cake-fuelled discussion, my daughter told me she had linked the use of ibuprofen for reducing a fever with helping her through the discomfort of well-earned DOMS. Rather than ‘endure’ the discomfort, she wanted a quick solution. If my 9-year-old daughter can make that connection, it is not difficult for others. Unfortunately, there is still excessive prophylactic use of prescribed …

A common question in sports injury research is ‘what proportion of athletes sustained an injury over a certain time period?’. In cross-sectional studies, where data are collected at a single point in time, the prevalence proportion is simply the number of injured athletes divided by the total sample. In prospective cohort studies, caution is needed as the injury incidence proportion (proportion of newly injured athletes during the observation period) is likely to be underestimated by simply using the approach that is valid for cross-sectional studies. As a part of the BJSM methods matter series,1 we here compare the analytical approaches for cross-sectional studies and prospective cohort studies (ie, without censoring and with censoring, respectively) to help the reader accurately estimate incidence proportion in prospective studies. To describe the proportion of sports injuries occurring over a given time period, one can calculate the CIP. The CIP can be calculated with or without censoring (in this paper, we discuss the concept of ‘right censoring’, but use the term ‘censoring’ only). For instance, the number of injured runners in a 1-year prospective cohort study was 252 of 931.2 Hence, the CIP calculated without censoring is 27% …

Excellence for elite athletes demands painstaking attention to detail to all aspects of health, well-being and performance. Researcher and Olympic Taekwondo Gold Medalist Lauren Burns and coauthors1 use the power of the athlete story to argue strongly and convincingly that central to achieving excellence is durable interpersonal support. ‘If we look at an athlete as a whole person, there is a fundamental duty of care to ensure they are supported to become their best, most resilient self, both on and off the field. Athletes therefore need to be encouraged to seek interpersonal support that evolves as they move along their development pathway’. These sentences, both important, appear sequentially; but I will make one distinction—the onus to create a supportive environment should not rest primarily on athletes. Where then does the duty of care lie? According to Fisher et al ’s heuristic model,2 the power differential in sport particularly positions coaches to hurt or help their athletes, and as such coaches are responsible for athlete’s welfare. Those, …

Rehabilitation of soft-tissue injuries can be complex. Over the years, acronyms guiding their management have evolved from ICE to RICE , then on to PRICE and POLICE .1 Although widely known, these previous acronyms focus on acute management, unfortunately ignoring subacute and chronic stages of tissue healing. Our contemporary acronyms encompass the rehabilitation continuum from immediate care ( PEACE ) to subsequent management ( LOVE ). PEACE and LOVE (figure 1) outline the importance of educating patients and addressing psychosocial factors to enhance recovery. While anti-inflammatories show benefits on pain and function, our acronyms flag their potential harmful effects on optimal tissue repair. We suggest that they may not be included in the standard management of soft-tissue injuries. Figure 1 PEACE and LOVE acronyms. ### P for protect Unload or restrict movement for 1–3 days to minimise bleeding, prevent distension of injured fibres and reduce the risk of aggravating the injury. Rest should be minimised as prolonged rest can compromise tissue strength and quality.1 Pain signals should guide the cessation of protection. ### E for elevate Elevate the limb higher …

Objective To determine whether antioxidant supplements and antioxidant-enriched foods can prevent or reduce delayed-onset muscle soreness after exercise. Methods We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, SPORTDiscus, trial registers, reference lists of articles and conference proceedings up to February 2017. Results In total, 50 studies were included in this review which included a total of 1089 participants (961 were male and 128 were female) with an age range of 16–55 years. All studies used an antioxidant dosage higher than the recommended daily amount. The majority of trials (47) had design features that carried a high risk of bias due to selective reporting and poorly described allocation concealment, potentially limiting the reliability of their findings. We rescaled to a 0–10 cm scale in order to quantify the actual difference between groups and we found that the 95% CIs for all five follow-up times were all well below the minimal important difference of 1.4 cm: up to 6 hours (MD −0.52, 95% CI −0.95 to −0.08); at 24 hours (MD −0.17, 95% CI −0.42 to 0.07); at 48 hours (mean difference (MD) −0.41, 95% CI −0.69 to −0.12); at 72 hours (MD −0.29, 95% CI −0.59 to 0.02); and at 96 hours (MD −0.03, 95% CI −0.43 to 0.37). Thus, the effect sizes suggesting less muscle soreness with antioxidant supplementation were very unlikely to equate to meaningful or important differences in practice. Conclusions There is moderate to low-quality evidence that high-dose antioxidant supplementation does not result in a clinically relevant reduction of muscle soreness after exercise of up to 6 hours or at 24, 48, 72 and 96 hours after exercise. There is no evidence available on subjective recovery and only limited evidence on the adverse effects of taking antioxidant supplements.

Objectives To identify common recommendations for high-quality care for the most common musculoskeletal (MSK) pain sites encountered by clinicians in emergency and primary care (spinal (lumbar, thoracic and cervical), hip/knee (including osteoarthritis [OA] and shoulder) from contemporary, high-quality clinical practice guidelines (CPGs). Design Systematic review, critical appraisal and narrative synthesis of MSK pain CPG recommendations. Eligibility criteria Included MSK pain CPGs were written in English, rated as high quality, published from 2011, focused on adults and described development processes. Excluded CPGs were for: traumatic MSK pain, single modalities (eg, surgery), traditional healing/medicine, specific disease processes (eg, inflammatory arthropathies) or those that required payment. Data sources Four scientific databases (MEDLINE, Embase, CINAHL and Physiotherapy Evidence Database) and four guideline repositories. Results 6232 records were identified, 44 CPGs were appraised and 11 were rated as high quality (low back pain: 4, OA: 4, neck: 2 and shoulder: 1). We identified 11 recommendations for MSK pain care: ensure care is patient centred, screen for red flag conditions, assess psychosocial factors, use imaging selectively, undertake a physical examination, monitor patient progress, provide education/information, address physical activity/exercise, use manual therapy only as an adjunct to other treatments, offer high-quality non-surgical care prior to surgery and try to keep patients at work. Conclusion These 11 recommendations guide healthcare consumers, clinicians, researchers and policy makers to manage MSK pain. This should improve the quality of care of MSK pain.

Objective To determine the effectiveness of conservative treatment (CT) on pain and function in patients with patellar tendinopathy (PT) compared with minimal intervention (MI) or other invasive intervention, or in addition to decline eccentric squat. Methods Searches were performed in MEDLINE, Embase, Cochrane, PEDro, SPORTDiscus, CINAHL and AMED databases. All randomised trials that evaluated CT (any intervention not involving invasive procedures or medication) in individuals with PT were included. Two reviewers screened studies, extracted data and assessed risk of bias of all included studies. Where suitable, meta-analyses were conducted; we assessed certainty of the evidence using GRADE methodology. Results When compared with MI, CT did not improve pain (weighted mean difference (WMD) −2.6, 95% CI −6.5 to 1.2) or function (WMD 1.8, 95% CI −2.4 to 6.1) in the short-term (up to 3 months) follow-up. When compared with invasive intervention, CT did not improve pain (WMD 0.7, 95% CI −0.1 to 1.4) or function (WMD −6.6, 95% CI −13.3 to 0.2) in the short-term follow-up. No overall effects were found for combined CT (when a conservative intervention was added to decline eccentric squat) on pain (WMD −0.5, 95% CI −1.4 to 0.4) or function (WMD −2.3, 95 % –9.1 to 4.6) at short-term follow-up. Single studies showed an effect on pain with iontophoresis at short-term follow-up (d = 2.42) or dry needling at medium/long-term follow-up (d = 1.17) and function with exercise intervention at medium/long-term follow-up (over 3 months) (d = 0.83). Summary/Conclusion Our estimates of treatment effect have only low to very low certainty evidence to support them. This field of sports medicine/sports physiotherapy urgently needs larger, high-quality studies with pain and function among the potential primary outcomes.

Objectives To determine whether individuals who sustained a sports concussion would exhibit persistent impairments in gait and quiet standing compared to non-injured controls during a dual-task assessment . Design Systematic review and meta-analysis using individual participant data (IPD). Data sources The search strategy was applied across seven electronic bibliographic and grey literature databases: MEDLINE, EMBASE, CINAHL, SportDISCUS, PsycINFO, PsycARTICLES and Web of Science, from database inception until June 2017. Eligibility criteria for study selection Studies were included if; individuals with a sports concussion and non-injured controls were included as participants; a steady-state walking or static postural balance task was used as the primary motor task; dual-task performance was assessed with the addition of a secondary cognitive task; spatiotemporal, kinematic or kinetic outcome variables were reported, and; included studies comprised an observational study design with case–control matching. Data extraction and synthesis Our review is reported in line with the Preferred Reporting Items for Systematic review and Meta-Analyses-IPD Statement. We implemented the Risk of Bias Assessment tool for Non-randomised Studies to undertake an outcome-level risk of bias assessment using a domain-based tool. Study-level data were synthesised in one of three tiers depending on the availability and quality of data: (1) homogeneous IPD; (2) heterogeneous IPD and (3) aggregate data for inclusion in a descriptive synthesis. IPD were aggregated using a ‘one-stage’, random-effects model. Results 26 studies were included. IPD were available for 20 included studies. Consistently high and unclear risk of bias was identified for selection, detection, attrition, and reporting biases across studies. Individuals with a recent sports concussion walked with slower average walking speed (χ2=51.7; df=4; p<0.001; mean difference=0.06 m/s; 95% CI: 0.004 to 0.11) and greater frontal plane centre of mass displacement (χ2=10.3; df=4; p=0.036; mean difference −0.0039 m; 95% CI: −0.0075 to −0.0004) than controls when evaluated using a dual-task assessment up to 2 months following concussion. Summary/conclusions Our IPD evidence synthesis identifies that, when evaluated using a dual-task assessment, individuals who had incurred a sports concussion exhibited impairments in gait that persisted beyond reported standard clinical recovery timelines of 7–10 days. Dual-task assessment (with motion capture) may be a useful clinical assessment to evaluate recovery after sports concussion. Protocol pre-registration This systematic review was prospectively registered in PROSPERO CRD42017064861.

Objective We compared data from the National Collegiate Athletic Association (NCAA) Concussion Study (1999–2001) and the NCAA-Department of Defense Concussion Assessment, Research and Education (CARE) Consortium (2014–2017) to examine how clinical management, return to play (RTP) and risk of repeat concussion in collegiate football players have changed over the past 15 years. Methods We analysed data on reported duration of symptoms, symptom-free waiting period (SFWP), RTP and occurrence of within-season repeat concussion in collegiate football players with diagnosed concussion from the NCAA Study (n=184) and CARE (n=701). Results CARE athletes had significantly longer symptom duration (CARE median=5.92 days, IQR=3.02–9.98 days; NCAA median=2.00 days, IQR=1.00–4.00 days), SFWP (CARE median=6.00 days, IQR=3.49–9.00 days; NCAA median=0.98 days, IQR=0.00–4.00 days) and RTP (CARE median=12.23 days, IQR=8.04–18.92 days; NCAA median=3.00 days, IQR=1.00–8.00 days) than NCAA Study athletes (all p<0.0001). In CARE, there was only one case of repeat concussion within 10 days of initial injury (3.7% of within-season repeat concussions), whereas 92% of repeat concussions occurred within 10 days in the NCAA Study (p<0.001). The average interval between first and repeat concussion in CARE was 56.41 days, compared with 5.59 days in the NCAA Study (M difference=50.82 days; 95% CI 38.37 to 63.27; p<0.0001). Conclusion Our findings indicate that concussion in collegiate football is managed more conservatively than 15 years ago. These changes in clinical management appear to have reduced the risk of repetitive concussion during the critical period of cerebral vulnerability after sport-related concussion (SRC). These data support international guidelines recommending additional time for brain recovery before athletes RTP after SRC.

Introduction The brain plays a key role in the perceptual regulation of exercise, yet neuroimaging techniques have only demonstrated superficial brain areas responses during exercise, and little is known about the modulation of the deeper brain areas at different intensities. Objectives/methods Using a specially designed functional MRI (fMRI) cycling ergometer, we have determined the sequence in which the cortical and subcortical brain regions are modulated at low and high ratings perceived exertion (RPE) during an incremental exercise protocol. Results Additional to the activation of the classical motor control regions (motor, somatosensory, premotor and supplementary motor cortices and cerebellum), we found the activation of the regions associated with autonomic regulation (ie, insular cortex) (ie, positive blood-oxygen-level-dependent (BOLD) signal) during exercise. Also, we showed reduced activation (negative BOLD signal) of cognitive-related areas (prefrontal cortex), an effect that increased during exercise at a higher perceived intensity (RPE 13–17 on Borg Scale). The motor cortex remained active throughout the exercise protocol whereas the cerebellum was activated only at low intensity (RPE 6–12), not at high intensity (RPE 13–17). Conclusions These findings describe the sequence in which different brain areas become activated or deactivated during exercise of increasing intensity, including subcortical areas measured with fMRI analysis.

Return to sport (RTS) is a dynamic process, during which practitioners must balance the risk that early reintegration to training/match-play increases reinjury risk with the benefit to the team of having key players available.1 Medical and performance staff must work together to formulate a plan considering the individual, the specifics of the injury, tissue healing time and potential risk factors for reinjury. A key element of this plan is the management and prescription of external running loads using global positioning systems (GPS) to return players to previous levels of chronic load prior to injury, relatively quickly and safely.2 3 Alongside …

OA is a leading cause of disability worldwide and associated with pain, impaired mobility and quality of life.1 Physical activity, including therapeutic exercise, patient education and weight control are recommended in key OA treatment guidelines.2 Nevertheless, the belief that therapeutic exercise may harm knee joint cartilage remains common among people with knee OA, and health professionals treating the condition, creating a prevailing barrier to implementing evidence-based care.3–5 The current discord between evidence and persistent beliefs highlights the need for better education. Providing a clear and engaging summary of the evidence to communicate the positive impact of therapeutic exercise and physical activity on the knee joint is crucial to encourage greater acceptance of, and participation in exercise and physical activity to …

Tramadol is a synthetic opioid widely used for the management of pain in sport setting.1 Tramadol is considered an effective substance to reduce acute and chronic pain because it acts by binding to the μ-opioid receptor to induce analgesia and sedation. However, tramadol also inhibits serotonin and norepinephrine reuptake and thus, it might play a role in the regulation of mood. In the past years, tramadol has caught attention of media and antidoping authorities because this substance might be the subject of abuse in some sports, notably cycling.2 WADA determined that the use of some narcotics are …