Athlete Fear Avoidance, Depression, and Anxiety Are Associated with Acute Concussion Symptoms in Athletes.

Background: Assessing sport-related concussions in athletes presents challenges due to symptom variability. This study aimed to explore the relationship between acute concussion symptoms and athlete fear avoidance, pain catastrophizing, depression, and anxiety. Anxiety and depression have previously been associated with the number of symptoms after a concussion, but no prior research has examined the possible link between athlete fear avoidance and acute concussion symptoms. Methods: Thirty-four collegiate athletes (mean age = 20.9 ± 1.8 years) were assessed within 48 h of a concussion using the Sport Concussion Assessment Tool 5, Athlete Fear Avoidance Questionnaire (AFAQ), Pain Catastrophizing Scale, and Hospital Anxiety and Depression Scale. Results: Results showed a significant association between the athlete fear avoidance and the number of concussion symptoms (r = 0.493, p = 0.003), as well as depression and anxiety measured by HADS (r = 0.686, p < 0.001). Athlete fear avoidance and HADS scores were predictors of symptom severity, explaining 41% of the variance (p = 0.001). Athletes with higher fear avoidance tended to report more symptoms post concussion. Conclusions: This study underscores the link between athlete fear avoidance, anxiety, depression, and the severity of concussion symptoms. Administering the AFAQ to assess athlete fear avoidance at the initial assessment of a concussion may be helpful in interpreting the symptoms of an acute concussion.

Structural maturation of myofilaments in engineered 3D cardiac microtissues characterized using small angle x-ray scattering.

Understanding the structural and functional development of human-induced pluripotent stem-cell-derived cardiomyocytes (hiPSC-CMs) is essential to engineering cardiac tissue that enables pharmaceutical testing, modeling diseases, and designing therapies. Here we use a method not commonly applied to biological materials, small angle x-ray scattering, to characterize the structural development of hiPSC-CMs within three-dimensional engineered tissues during their preliminary stages of maturation. An x-ray scattering experimental method enables the reliable characterization of the cardiomyocyte myofilament spacing with maturation time. The myofilament lattice spacing monotonically decreases as the tissue matures from its initial post-seeding state over the span of 10 days. Visualization of the spacing at a grid of positions in the tissue provides an approach to characterizing the maturation and organization of cardiomyocyte myofilaments and has the potential to help elucidate mechanisms of pathophysiology, and disease progression, thereby stimulating new biological hypotheses in stem cell engineering.

Effect of aquatic exercise versus standard care on paraspinal and gluteal muscles morphology in individuals with chronic low back pain: a randomized controlled trial protocol.

BACKGROUND: Low back pain (LBP) is one of the most disabling diseases and a major health issue. Despite the evidence of a link between paraspinal and gluteal muscle dysfunction and LBP, it is unknown whether aquatic exercises can lead to improvements in paraspinal and gluteal muscle morphology and function, and whether improvements in overall muscle health are associated with improvements in patients' outcomes. The unique properties of water allow a water-based exercise program to be tailored to the needs of those suffering from LBP. This study uses magnetic resonance imaging (MRI) to investigate the effect of an aquatic exercise program versus standard exercise on 1) paraspinal and gluteal muscle size, quality and strength and 2) pain, disability, and psychological factors (pain related fear, depression, anxiety, sleep quality) in chronic LBP. METHODS: This study will include 34 participants with chronic non-specific LBP and moderate to severe disability, aged between 18 and 65, who will be randomly assigned (1:1) to the aquatic exercise group or land-based standard care exercise group. Both groups will receive 20 supervised sessions, twice per week over 10 weeks. MRIs will be obtained along the lumbosacral spine (L1-L5) and pelvis at the start and end of the intervention to assess the effect of each exercise intervention on paraspinal and gluteal muscle size and quality. Pre- to post-intervention changes in all outcomes between each group will be assessed, and the association between the changes in back muscle quality and clinical outcomes will be examined. Between-subjects repeated measure analysis of variance will be used to examine the changes in paraspinal muscle morphology over the different time points. Linear mixed models will be used to assess whether baseline scores can modify the response to the exercise therapy treatment. DISCUSSION: This study will determine if water-based exercises targeting the lower back and gluteal muscles can lead to important changes in muscle quality and function, and their possible relation with patients' pain and functional improvements. Our findings will have strong clinical implications and provide preliminary data to design a community program to better support individuals with chronic LBP. TRIAL REGISTRATION: NCT05823857, registered prospectively on April 27th, 2023.

The Effects of Combined Motor Control and Isolated Extensor Strengthening versus General Exercise on Paraspinal Muscle Morphology, Composition, and Function in Patients with Chronic Low Back Pain: A Randomized Controlled Trial.

Low back pain (LBP), a globally widespread and persistent musculoskeletal disorder, benefits from exercise therapy. However, it remains unclear which type leads to greater changes in paraspinal muscle health. This study aimed to (1) compare the effects of a combined motor control and isolated lumbar extension exercise (MC+ILEX) versus a general exercise (GE) intervention on paraspinal muscle morphology, composition, and function, and (2) examine whether alterations in paraspinal muscle health were correlated with improvements in pain, function, and quality of life. Fifty participants with chronic LBP were randomly assigned to each group and underwent a 12-week supervised intervention program. Magnetic resonance imaging and ultrasound assessments were acquired at baseline, 6 and 12 weeks to examine the impact of each intervention on erector spinae (ES) and multifidus (MF) muscle size (cross-sectional area, CSA), composition, and function at L4-L5 and L5-S1. Self-reported questionnaires were also acquired to assess participant-oriented outcomes. Our findings indicated that the MC+ILEX group demonstrated greater improvements in MF and ES CSA, along with MF thickness at both levels (all p < 0.01). Both groups significantly improved in pain, function, and quality of life. This study provided preliminary results suggesting that an MC+ILEX intervention may improve paraspinal morphology while decreasing pain and disability.

Efficacy of topical versus oral analgesic medication compared to a placebo in injured athletes: A systematic review with meta-analysis.

BACKGROUND: Athletes are injured frequently and often take analgesic medication. Moreover, athletes commonly use non-prescription topical and oral medications with little guidance. Despite wide use, relatively few studies exist on the efficacy of pain medication in injured athletes compared to a placebo. OBJECTIVE: To determine efficacy of topical or oral medications in pain reduction compared to a placebo in injured athletes. STUDY DESIGN: A systematic review and meta-analysis. METHODS: We conducted an electronic search using Medline/Pubmed, Web of Science, Ovid, and SportDiscus for all literature relating to topical or oral medications in athletes for pain management post-injury. Two reviewers screened the studies and measured their quality. To determine efficacy, we calculated the Hedges' g value. We created forest plots with 95% CI to graphically summarize the meta-analyses. RESULTS: There was a significant pooled effect size reflecting a reduction in pain outcomes for the topical treatment versus placebo (g = -0.64; 95% CI [-0.89, -0.39]; p < 0.001). There was not a significant reduction in pain outcomes for the oral treatment versus placebo (g = -0.26; 95% CI [-0.60, 0.17]; p = 0.272). CONCLUSION: Topical medications were significantly better at reducing pain compared to oral medications versus a placebo in injured athletes. These results are different when compared to other studies that used experimentally induced pain versus musculoskeletal injuries. The results from our study suggest that athletes should use topical medications for pain reduction, as it is more effective, and there are less reported adverse effects compared to oral medication.

Longitudinal Validation of a Specific Measure of Fear Avoidance in Athletes: Predicting Time from Injury to Return to Sports Competition.

Purpose: We developed the Athlete Fear Avoidance Questionnaire (AFAQ) to measure fear avoidance in athletes. Previous fear avoidance scales were developed for the general population and have demonstrated significant predictive capabilities regarding rehabilitation. No research to date has examined the association between athlete fear avoidance as measured by the AFAQ and the rehabilitation time in athletes. Patients and Methods: Fifty-nine athletes who were injured during sport season participated in the study (40 males and 19 females). At injury onset, all participants completed self-report functional questionnaires. In addition, we measured multiple aspects of fear avoidance including athlete fear avoidance (AFAQ), kinesiophobia (TSK), and pain catastrophizing (PCS). Finally, we assessed pain severity and interference, as well as depression. Once the athletes were able to return to competition all participants answered the questionnaires again. Pearson correlations and a regression analysis were used to identify relationships between function, psychological variables, pain, and return to competition time. Results: The AFAQ yielded the strongest correlation with return to competition time (r=0.544, p<0.001). In addition, function at initial injury time and pain interference were also significantly correlated with return to competition time (r=0.442, p<0.001 and r=0.356, p=0.006 respectively). Athlete fear-avoidance combined with function at the time of injury explained 34% of the variance of return to competition time in the multivariate regression model (p<0.001). Conclusion: Athlete fear-avoidance as measured by the AFAQ is associated with rehabilitation time and returning to competition in injured athletes. Psychosocial factors including athlete fear avoidance may explain why some athletes take longer to rehabilitate than others and should be evaluated in athletes who are taking longer than anticipated to complete their rehabilitation. Reducing athlete fear avoidance may facilitate rehabilitation in future studies.

The effect of phasic versus combined neuromuscular electrical stimulation using the StimaWELL 120MTRS system on multifidus muscle morphology and function in patients with chronic low back pain: a randomized controlled trial protocol.

BACKGROUND: Neuromuscular electrical stimulation (NMES) is used to improve muscle strength clinically when rehabilitating various musculoskeletal disorders. However, the effects of NMES on muscle morphology and function in individuals with non-specific chronic low back pain (CLBP) have scarcely been investigated. Although research links deficits in the paraspinal musculature with subjective reports of pain and disability, it is unknown if treatment with NMES can help reverse these deficits. Therefore, the primary aim of this study is to compare the effects of two muscle therapy protocols with a medium-frequency electrotherapy device (the StimaWELL 120MTRS system) on multifidus muscle morphology and function in CLBP patients. The secondary aims are to determine the effects of these protocols subjective reports of pain intensity, pain interference, disability, and catastrophizing. METHODS: A total of 30 participants with non-specific CLBP, aged 18-60, will be recruited from local orthopedic clinics and databases. Participants will be randomized (1:1) to either the phasic or combined (phasic + tonic) muscle therapy protocols on the StimaWELL 120MTRS system. Participants will undergo 20 supervised electrotherapy treatments over a 10-week period. The primary outcomes will be multifidus morphology (e.g. cross-sectional area (CSA), fat infiltration) and function (e.g., contraction measured via %thickness change from a rested to contracted state, and stiffness at rest and during contraction). Secondary outcomes will include pain intensity, interference, disability, and catastrophizing. Both primary and secondary outcomes will be obtained at baseline and at 11-weeks; secondary outcomes measured via questionnaires will also be obtained at 6-weeks, while LBP intensity will be measured before and after each treatment. Paired t-tests will be used to assess within-group changes for all primary outcome measures. A two-way repeated-measures analysis of variance will be used to assess changes in secondary outcomes over time. DISCUSSION: The results of this trial will help clarify the role of medium-frequency NMES on lumbar multifidus morphology and function. TRIAL REGISTRATION: NCT04891692, registered retrospectively on May 18, 2021.

Cross-cultural adaptation and validation of the Athlete Fear Avoidance Questionnaire in Italian university athletes with musculoskeletal injuries.

The aim of this study was to translate, culturally adapt and validate an Italian version of the Athlete Fear Avoidance Questionnaire (AFAQ-I). We conducted a cross-sectional evaluation of the psychometric properties of the AFAQ-I in university athletes with musculoskeletal injuries, culturally adapting it in accordance with international standards. Psychometric evaluation included the assessment of structural validity (exploratory factor analysis), internal consistency (Cronbach's alpha and inter-item correlation), test-retest reliability [intraclass correlation coefficient, (ICC) (2,1)], measurement error and minimum detectable change (MDC). To examine construct validity, we compared (Spearman ρ) the AFAQ-I with a numerical pain rating scale (NPRS), the Pain Catastrophizing Scale (PCS) and the Fear Avoidance Beliefs Questionnaire (FABQ) subscales [FABQ-Physical Activity (FABQ-PA) and FABQ-Work (FABQ-W)]. The AFAQ-I was administered to 133 university athletes with musculoskeletal injuries (95 males and 38 females; mean age 25 years, SD 5; mean average pain duration 5.6 months, SD 8.7). Factor analysis revealed an acceptable 1-factor 10-item solution (explained common variance at minimum rank factor analysis: 0.74) although a couple of items (#6 and 9) presented low factor loadings, suggesting the presence of a small secondary dimension. Cronbach's alpha was 0.78 and the average inter-item correlation was 0.27. ICC (2,1) was 0.95 and the MDC was 4.4 points. As hypothesized a priori, the AFAQ-I moderately correlated with NPRS (ρ = 0.42), PCS (ρ = 0.59), FABQ-PA (ρ = 0.40) and FABQ-W (ρ = 0.34). In conclusion, the AFAQ-I is a valid Italian translation of AFAQ that demonstrates acceptable psychometric properties. However, we recommend further analysis of the construct definition of the AFAQ and additional examination of its structural validity.

Patient Outcomes After Treatment by Athletic Therapy Students.

CONTEXT: Patient-reported outcome measures (PROMs) should be used in athletic training and athletic therapy but are rarely incorporated in internships. Student-run clinics are common in other health professions and provide effective treatment and valuable learning environments. To our knowledge, no one has evaluated rehabilitation outcomes in patients treated by athletic therapy students (ATSs). OBJECTIVE: To measure the improvement in function in injured patients seeking treatment at an ATS clinic. DESIGN: Cohort study. SETTING: An ATS clinic. PATIENTS OR OTHER PARTICIPANTS: A total of 59 patients (32 women, age = 33.9 ± 14.7 years; 27 men, age = 38 ± 14.4 years) from the community with a variety of low back, lower extremity, and upper extremity injuries participated. MAIN OUTCOME MEASURE(S): At baseline and 6-week follow-up, all patients completed 1 of 3 scales (depending on their injury location) to assess their injured level of function. Scales were the Oswestry Disability Index for low back injuries; Lower Extremity Functional Scale for lower extremity injuries; and Disabilities of the Arm, Shoulder and Hand for upper extremity injuries. RESULTS: On average, patients received 4.7 ± 1.8 treatments across 48.8 ± 16.1 days. They experienced an increase in function between baseline and follow-up assessments (18.8% ± 20.3%; P < .001, Cohen d = 1.06). Moreover, the amount of functional improvement was clinically meaningful, as it was greater than the minimal clinically important difference for each scale. The efficacy of treatments did not differ according to the internship experiences of the ATSs. CONCLUSIONS: Function improved in patients after treatment delivered by an ATS. Patient-reported outcome measures were useful for the students in monitoring patient improvement, but more research is needed regarding effective treatments for patients with chronic pain. Our results suggested that ATS clinics provide effective treatments for patients, service to the community, and a learning opportunity for students.

Elevated Heart Rate and Pain During a Cold Pressor Test Correlates to Pain Catastrophizing.

To understand the variable response to pain, researchers have examined the change in cardiovascular measures to a uniform painful stimulation. Pain catastrophizing is the tendency to magnify or exaggerate pain sensations, and it affects the outcome of rehabilitation in a clinical setting. Its effect on cardiovascular changes during a painful stimulus is unclear. Twenty-four healthy human participants completed the study. All participants completed a cold pressor test while subjective pain intensity was measured with a numeric pain scale from 0-10. Continuous cardiac output measurements were obtained with finger-pulse plethysmograph waveform analysis. The measurements included systolic and diastolic blood pressure, heart rate averaged over 30 s intervals. Pain catastrophizing and anxiety were assessed using the pain catastrophizing scale (PCS), and Spielberger's State-Trait Anxiety Inventories, respectively. Peak pain was correlated to pain catastrophizing (r = 0.628, p < 0.01). There was a strong correlation between change in heart rate (HR) and subjective peak pain (r = 0.805, p < 0.01), total PCS (r = 0.474, p < 0.05), and the helplessness subscale of the PCS (r = 0.457, p < 0.05). Peak pain and catastrophizing explained a significant amount of the variance for the change in HR during the cold pressor test (R2 of 0.649 and 0.224 respectively, p = 0.019). These novel findings demonstrate a psycho-physiological relationship between cardiovascular changes and pain catastrophizing. Further research should include participants with subacute or persistent pain.

The effects of combined motor control and isolated extensor strengthening versus general exercise on paraspinal muscle morphology and function in patients with chronic low back pain: a randomised controlled trial protocol.

BACKGROUND: Exercise is a common approach for the management of patients with chronic non-specific low back pain (LBP). However, there is no clear mechanistic evidence or consensus on what type of exercise is more effective than others. While considerable evidence suggests a link between lumbar muscle health (e.g., atrophy and fatty infiltration) with functional deficits, it is unknown whether exercises targeting the lumbar spine can lead to noticeable improvements in muscle health and functional outcomes. The primary aim of this study is to compare the effect of combined motor control and isolated strengthening lumbar exercises (MC + ILEX) versus a general exercise group (GE) on multifidus muscle morphology (size and composition). Secondary aims include assessing the effect of the interventions on overall paraspinal muscle health, pain and disability, as well as psychological factors as possible effect modifiers. METHODS: A total of 50 participants with chronic non-specific LBP and moderate to severe disability, aged between 18 and 60, will be recruited from the local orthopaedic clinics and university community. Participants will be randomised (1:1) to either the MC + ILEX or GE group. Participants will undergo 24 individually supervised exercise sessions over a 12-week period. The primary outcome will be multifidus morphology (atrophy) and composition (fatty infiltration). Secondary outcomes will be muscle function (e.g., % thickness change during contraction), morphology, lumbar extension strength, pain intensity and disability. Potential treatment effect modifiers including maladaptive cognitions (fear of movement, catastrophizing), anxiety, depression, physical activity, and sleep quality will also be assessed. All measurements will be obtained at baseline, 6-week and 12-week; self-reported outcomes will also be collected at 24-week. Between-subjects repeated measure analysis of variance will be used to examine the changes in paraspinal muscle morphology over the different time points. Linear mixed models will be used to assess whether baseline scores can modify the response to the exercise therapy treatment. DISCUSSION: The results of this study will help clarify which of these two common interventions promote better results in terms of overall paraspinal muscle heath, back pain, disability and psychological factors in adults with chronic LBP. TRIAL REGISTRATION: NTCT04257253 , registered prospectively on February 5, 2020.

Association Between Pain Catastrophizing and Pain and Cardiovascular Changes During a Cold-Pressor Test in Athletes.

CONTEXT: Athletes are often exposed to pain due to injury and competition. Using preliminary evidence, researchers have shown that cardiovascular measures could be an objective measure of pain, but the cardiovascular response can be influenced by psychological factors, such as catastrophizing. OBJECTIVE: To use a painful cold-pressor test (CPT) to measure the relationship among catastrophizing, pain, and cardiovascular variables in athletes. DESIGN: Cohort study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 36 male rugby athletes (age = 24.0 ± 4.6 years, height = 180.0 ± 6.1 cm, mass = 90.5 ± 13.8 kg). MAIN OUTCOME MEASURE(S): We measured catastrophizing using the Pain Catastrophizing Scale and pain using a numeric pain rating scale. Cardiovascular measures were heart rate, systolic and diastolic blood pressure, and heart rate variability. RESULTS: During the CPT, participants experienced increases in pain (from 0 to 4.1 ± 2.2), systolic blood pressure (from 126.7 ± 16.5 to 149.7 ± 23.4 mm Hg), diastolic blood pressure (from 76.9 ± 8.3 to 91.9 ± 11.5 mm Hg), and heart rate variability (from 0.0164 ± 0.0121 to 0.0400 ± 0.0323 milliseconds; all P values < .001). In addition, we observed a decrease in heart rate after the CPT (P = .04). We found a correlation between athletes' pain catastrophizing and both pain intensity and change in heart rate during the CPT (P = .02 and P = .003, respectively). Linear regression indicated that pain and catastrophizing explained 29% of the variance in the change in heart rate (P = .003). CONCLUSIONS: Athletes who had catastrophizing thoughts were more likely to experience higher levels of pain and a greater cardiovascular response during a painful stimulus. The change in cardiovascular variables may be a good objective measure of pain in athletes in the future.

Pain catastrophizing in athletes correlates with pain and cardiovascular changes during a painful cold pressor test.

CONTEXT: Athletes are often exposed to pain due to injury and competition. There is preliminary evidence that cardiovascular measures could be an objective measure of pain, but the cardiovascular response can be influenced by psychological factors such as catastrophizing. OBJECTIVES: The purpose of our study was to use a painful cold pressor test to measure the relationship between catastrophizing, pain, and cardiovascular variables in athletes. DESIGN: Pre-post test. SETTING: We completed all measures in a laboratory setting. PARTICIPANTS: Thirty-six male rugby athletes participated in the study. MAIN OUTCOME MEASURES: We measured catastrophizing with the Pain Catastrophizing Scale and pain with a Numeric Pain Rating Scale. Cardiovascular measures included heart rate, systolic, and diastolic blood pressure, and heart rate variability. RESULTS: During the cold pressor test, participants experienced a significant increase in pain (0 to 4.1±2.2), systolic blood pressure (126.7±16.5mm Hg to 149.7±23.4mm Hg), diastolic blood pressure (76.9±8.3mm Hg to 91.9±11.5mm Hg) and heart rate variability (from 0.0164ms±0.0121 to 0.0400ms±0.0323) (all p<.001). In addition, there was a significant decrease in heart rate after the cold pressor test (p=0.04). There was a significant correlation between athlete's pain catastrophizing to both pain intensity and change in heart rate during the cold pressor test (p=.017 and p=.003 respectively). A significant linear regression indicated pain and catastrophizing explained 29% of the variance of the change in heart rate (p=.003). CONCLUSION: Athletes who have catastrophizing thoughts are more likely to experience higher levels of pain and a greater cardiovascular response during a painful stimulus. The change in cardiovascular variables may be a good alternative for an objective measure of pain in athletes in the future.

3D Printing of Viscoelastic Suspensions via Digital Light Synthesis for Tough Nanoparticle-Elastomer Composites.

The rheological parameters required to print viscoelastic nanoparticle suspensions toward tough elastomers via Digital Light Synthesis (DLS) (an inverted projection stereolithography system) are reported. With a model material of functionalized silica nanoparticles suspended in a poly(dimethylsiloxane) matrix, the rheological-parameters-guided DLS can print structures seven times tougher than those formed from the neat polymers. The large yield stress and high viscosity associated with these high concentration nanoparticle suspensions, however, may prevent pressure-driven flow, a mechanism essential to stereolithography-based printing. Thus, to better predict and evaluate the printability of high concentration nanoparticle suspensions, the boundary of rheological properties compatible with DLS is defined using a non-dimensional Peclet number (Pe). Based on the proposed analysis of rheological parameters, the border of printability at standard temperature and pressure (STP) is established by resin with a silica nanoparticle mass fraction (ϕsilica ) of 0.15. Above this concentration, nanoparticle suspensions have Pe > 1 and are not printable. Beyond STP, the printability can be further extended to ϕsilica = 0.20 via a heating module with lower shear rate to reduce the Pe < 1. The printed rubber possesses even higher toughness (Γ ≈ 155 kJ m-3 ), which is 40% higher over that of ϕsilica = 0.15.

Chronic Pain Patients' Kinesiophobia and Catastrophizing are Associated with Activity Intensity at Different Times of the Day.

PURPOSE: To examine the relationship between baseline kinesiophobia and baseline pain catastrophizing with the 4-day average activity intensity at different times of the day while accounting for different wake and sleep-onset times in chronic pain patients. METHODS: Twenty-one participants suffering from idiopathic chronic pain completed baseline questionnaires about kinesiophobia, catastrophizing, disability, depression, and pain. We measured the participants' activity using accelerometers and calculated activity intensity in the morning, afternoon, and evening. We performed a 2-way repeated measures ANOVA to compare activity levels at different times of the day, and multiple linear regressions. RESULTS: Baseline kinesiophobia was significantly associated with 4-day average evening light activity and sedentary activity at all time periods while baseline catastrophizing was significantly associated with increased 4-day average light activity in the evening and more moderate to vigorous activity in the morning. Our participants engaged in more light activity on average than sedentary activity, and very little moderate-vigorous activity. Participants were most active in the afternoon. CONCLUSION: Baseline kinesiophobia and baseline catastrophizing were not associated with the 4-day average total daily activity; however, they were associated with 4-day average activity intensities at different times throughout the day. Segmenting daily activity into morning, afternoon, evening may influence the relationship between daily activity, and kinesiophobia and pain catastrophizing. Individuals with chronic pain are less sedentary than previously thought which may affect future interventions.

Low Back Pain Treatment by Athletic Trainers and Athletic Therapists: Biomedical or Biopsychosocial Orientation?

CONTEXT: Low back pain (LBP) remains a societal burden due to consistently high rates of recurrence and chronicity. Recent evidence suggested that a provider's treatment orientation influences patient beliefs, the clinical approach, and subsequently, rehabilitation outcomes. OBJECTIVE: To characterize American athletic trainer (AT) and Canadian athletic therapist (C-AT) treatment orientations toward LBP. DESIGN: Cross-sectional study. SETTING: Online survey. PATIENTS OR OTHER PARTICIPANTS: A total of 273 ATs (response rate = 13.3%) and 382 C-ATs (response rate = 15.3%). MAIN OUTCOME MEASURE(S): Participants completed demographic questions and the Pain Attitudes and Beliefs Scale (PABS) for ATs/C-ATs. The PABS measures the biomedical and biopsychosocial treatment orientation of health care providers and is scored on a 6-point Likert scale. Descriptive statistics characterized the participants; t tests and 1-way analyses of variance identified differences between group means; and Spearman correlations assessed relationships between the biomedical and biopsychosocial scores and age, number of LBP patients per year, and years of experience. RESULTS: Athletic trainers treating 9 to 15 LBP patients per year had higher biomedical scores (35.0 ± 5.7) than ATs treating 16 to 34 (31.9 ± 5.5, P = .039) or >34 (31.7 ± 8.6, P = .018) LBP patients per year. The C-ATs treating 16 to 34 (31.8 ± 6.3, P = .038) and >34 (31.0 ± 6.7, P < .001) LBP patients per year had lower biomedical scores than those treating ≤8 LBP patients per year (34.8 ± 5.9). The C-ATs with ≤5 years of experience had higher biomedical scores than those with 10 to 15 (31.0 ± 6.7, P = .011) and 16 to 24 (29.8 ± 7.5, P < .001) years of experience. Canadian athletic therapists treating the general public had higher (31.7 ± 4.0) biopsychosocial scores than ATs treating athletes (31.3 ± 3.5, P = .006). The C-ATs ≤35.6 years of age had higher biomedical scores (33.1 ± 5.9) than those >35.6 years of age (30.5 ± 7.0, P < .001). CONCLUSIONS: Athletic trainers and C-ATs who treated more LBP patients per year were more likely to score low on a biomedical treatment orientation subscale. Because this orientation has predicted poor outcomes in other health care providers, further research is needed to determine the effects of ATs' and C-ATs' biomedical orientations on rehabilitation outcomes.

Prolonged Reduction in Shoulder Strength after Transcutaneous Electrical Nerve Stimulation Treatment of Exercise-Induced Acute Muscle Pain.

OBJECTIVES: Transcutaneous electrical nerve stimulation (TENS) is commonly used for reducing musculoskeletal pain to improve function. However, peripheral nerve stimulation using TENS can alter muscle motor output. Few studies examine motor outcomes following TENS in a human pain model. Therefore, this study investigated the influence of TENS sensory stimulation primarily on motor output (strength) and secondarily on pain and disability following exercise-induced delayed-onset muscle soreness (DOMS). METHODS: Thirty-six participants were randomized to a TENS treatment, TENS placebo, or control group after completing a standardized DOMS protocol. Measures included shoulder strength, pain, mechanical pain sensitivity, and disability. TENS treatment and TENS placebo groups received 90 minutes of active or sham treatment 24, 48, and 72 hours post-DOMS. All participants were assessed daily. RESULTS: A repeated measures analysis of variance and post-hoc analysis indicated that, compared to the control group, strength remained reduced in the TENS treatment group (48 hours post-DOMS, P < 0.05) and TENS placebo group (48 hours post-DOMS, P < 0.05; 72 hours post-DOMS, P < 0.05). A mixed-linear modeling analysis was conducted to examine the strength (motor) change. Randomization group explained 5.6% of between-subject strength variance (P < 0.05). Independent of randomization group, pain explained 8.9% of within-subject strength variance and disability explained 3.3% of between-subject strength variance (both P < 0.05). DISCUSSION: While active and placebo TENS resulted in prolonged strength inhibition, the results were nonsignificant for pain. Results indicated that higher pain and higher disability were independently related to decreased strength. Regardless of the impact on pain, TENS, or even the perception of TENS, may act as a nocebo for motor output.

Expectancy Reduces Symptoms but not Functional Impairment Following Exercise-induced Musculoskeletal Injury.

OBJECTIVES: To quantify the extent to which the participant-provider interaction influences the response to sham treatment following exercised-induced acute musculoskeletal pain. MATERIALS AND METHODS: In total, 40 participants between the ages of 18 and 35 volunteered for the study. Participants came to the laboratory for 3 test sessions 48-hour apart (day 1, 3, and 5). During the initial session, baseline measures were assessed and participants underwent a fatigue protocol for the biceps brachii. Participants were then assigned to a positive expectation or a no-expectation condition before receiving a sham laser therapy treatment. The positive expectation group received symptom improvement priming before their sham treatment. Participants allocated to the no-expectation condition received no feedback before the sham treatment. Maximum voluntary isometric contraction; relaxed elbow angle; visual analog scale; and the QuickDash questionnaire were used as outcome measures. RESULTS: The positive expectation group had a significant reduction in perceived pain compared with the no-expectation group at day 3 follow-up, with the mean scores being 34.65 mm (SE=4.44) compared with 49.4 mm (SE=5.79), respectively. There were no between-group differences with respect to maximum voluntary isometric contraction, QuickDash, or relaxed elbow angle outcomes. In addition, there were no significant between-group differences observed with expected pain on follow-up visits, the effect sizes were d=0.26 on day 1 for day 3 and d=0.51 on day for day 5. DISCUSSION: Positive expectations before a sham treatment enhanced reduction in pain intensity but did not improve functional impairments following exercise-induced acute musculoskeletal injury.

Development and Validation of the Athlete Fear Avoidance Questionnaire.

CONTEXT: The fear-avoidance model was developed in an attempt to explain the process by which "pain experience" and "pain behavior" become dissociated from the actual pain sensation in individuals who manifest the phenomenon of exaggerated pain perception. High levels of fear avoidance can lead to chronic pain and disability and have successfully predicted rehabilitation time in the work-related-injury population. Existing fear-avoidance questionnaires have all been developed for the general population, but these questionnaires may not be specific enough to fully assess fear avoidance in an athletic population that copes with pain differently than the general population. OBJECTIVE: To develop and validate the Athlete Fear Avoidance Questionnaire (AFAQ). DESIGN: Qualitative research to develop the AFAQ and a cross-sectional study to validate the scale. PATIENTS OR OTHER PARTICIPANTS: For questionnaire development, a total of 8 experts in the fields of athletic therapy, sport psychology, and fear avoidance were called upon to generate and rate items for the AFAQ. For determining concurrent validity, 99 varsity athletes from various sports participated. DATA COLLECTION AND ANALYSIS: A total of 99 varsity athletes completed the AFAQ, the Fear-Avoidance Beliefs Questionnaire, and the Pain Catastrophizing Scale. We used Pearson correlations to establish concurrent validity. RESULTS: Concurrent validity was established with significant correlations between the AFAQ and the Fear Avoidance Beliefs Questionnaire-Physical Activity (r = 0.352, P > .001) as well as with the Pain Catastrophizing Scale (r = 0.587, P > .001). High internal consistency of our questionnaire was established with a Cronbach α coefficient of 0.805. The final version of the questionnaire includes 10 items with good internal validity (P < .05). CONCLUSIONS: We developed a questionnaire with good internal and external validity. The AFAQ is a scale that measures sport-injury-related fear avoidance in athletes and could be used to identify potential psychological barriers to rehabilitation.

Unilateral eccentric exercise of the knee flexors affects muscle activation during gait.

Uni-lateral muscle soreness is common yet the effects on gait or electromyographic (EMG) activity are unknown. The purpose of our study was to induce delayed onset muscle soreness (DOMS) in the knee flexor group and measure the resultant change in EMG activity and knee motion during gait. Nine healthy subjects participated in the study. Measures of function, evoked tenderness of the biceps femoris, as well as knee angle, and EMG activity during gait were assessed prior and 48 h after an eccentric exercise protocol. DOMS was induced unilaterally in the knee flexors using an isokinetic dynamometer and subjects exercised until they could not generate 50% of their maximal voluntary isometric contraction (MVIC). There was a significant decrease in biceps femoris activity after DOMS during the last phase of gait. Moreover, there was a day × phase interaction for gastrocnemius activity with the last two phases displaying an increase in activity. There was no significant change in knee angle during gait. The decrease in biceps femoris activity as well as the increase in gastrocnemius activity could be evidence of a protective mechanism designed to decrease activity of the sore muscle while increasing the activity of a synergistic muscle.