Background: Knee disorders prevalence is estimated at more than 50% in a lifetime. There are over 250,000 anterior cruciate ligament (ACL) injuries per year in the United States. There are over 175,000 ACL reconstructions annually. This study was a double-blinded design to establish the reliability and validity of a new orthopedic device to measure linear translation of the tibia on the femur (ACL testing). Methods: A Zeiss Smartzoom microscope was used as the gold standard to assess the ability of the Mobil-Aider™ to measure linear translation. Sixty blinded measures were taken with each of 6 different devices. Results: Both the intraclass correlation and the Pearson correlation were .986. The Cronbach alpha reliability analysis was 0.992. Independent 1-sample t tests were performed on the differences between the Mobil-Aider™ and Zeiss values, and were not found to be significant (P = .42); that is, they were the same. Bland–Altman plot and a linear regression revealed no propositional bias. Finally, with 360 measures over 6 devices, the power of this study was calculated to be 100%. Discussion: This data are the first step in establishing reliability and concurrent validity of a new device. As a result of the current data, the Mobil-Aider™ device is deemed a promising orthopedic tool for use in assessing the laxity of the ACL. Additional testing needs to be performed on both healthy and injured knees. Conclusions: There is potential for the Mobil-Aider™ to contribute to the assessment of ACL injuries, but additional human testing is needed.
Salman Nazary-Moghadam, Mahyar Salavati, Ali Esteki, Behnam Akhbari, Sohrab Keyhani, and Afsaneh Zeinalzadeh
Objectives: The current study assessed the intrasession and intersession reliability of the knee flexion–extension Lyapunov exponent in patients with anterior cruciate ligament deficiency and healthy individuals. Study Design: University research laboratory. Methods: Kinematic data were collected in 14 patients with anterior cruciate ligament deficiency and 14 healthy individuals walked on a treadmill at a self-selected, low, and high speed, with and without cognitive load. The intraclass correlation coefficient, standard error of measurement, minimal metrically detectable change, and percentage of coefficient of variation were calculated to assess the reliability. Results: The knee flexion–extension Lyapunov exponent had high intrasession reliability, with intraclass correlation coefficients ranging from .83 to .98. In addition, the intersession intraclass correlation coefficient values of these measurements ranged from .35 to .85 regardless of group, gait speed, and dual tasking. In general, relative and absolute reliability were higher in the patients with anterior cruciate ligament deficiency than in the healthy individuals. Conclusions: Although knee flexion–extension Lyapunov exponent demonstrates good intrasession reliability, its low intersession reliability indicates that changes of these measurements between different days should be interpreted with caution.
Kenji Kanazawa, Yoshihiro Hagiwara, Takuya Sekiguchi, Ryo Fujita, Kazuaki Suzuki, Masashi Koide, Akira Ando, and Yutaka Yabe
Context: Range of motion (ROM) in the glenohumeral joint decreases with age in healthy subjects; however, the underlying mechanism remains unclear. The process of aging of the joint capsule, including the coracohumeral ligament (CHL), could affect ROM limitation. Objective: This study investigated correlations between elasticity of the CHL, evaluated by means of shear-wave elastography, and age, side dominance, and ROM in healthy individuals. Design: Experimental study. Setting: Laboratory. Subjects: Eighty-four healthy volunteers (39 men and 45 women, mean age: 42.6 y) were included. Main Outcome Measures: Subjects were divided into 3 age groups: younger (20–39 y), middle (40–59 y), and older (≥60 y) age groups. With participants in the supine position, CHL elasticity in both shoulders was evaluated in both neutral and 30° external rotation, with arms at the sides. ROM, including forward flexion, lateral elevation, external rotation, 90° abduction with external rotation, and hand behind the back were measured with participants in the standing position. Results: The CHL elastic modulus was higher in the older group than in the younger group in the neutral (78.4 kPa [SD: 37.1] and 56.6 kPa [SD: 31.7], respectively) and 30° external rotation positions (135.5 kPa [SD: 63.5] and 71.4 kPa [SD: 32.2], respectively). Negative correlations were found between the CHL elastic modulus and ROM in terms of 30° external rotation and both external rotation (R = −.59, P = .02) and 90° abduction with external rotation (R = −.71, P = .003) in the older group, with correlation coefficients increasing with age. Conclusions: Significant correlations were identified between CHL elasticity and ROM in both external rotation and 90° abduction with external rotation with increasing age. Decreased CHL elasticity was strongly associated with decreased shoulder ROM in middle-aged and older individuals.
Tobias Lundgren, Gustaf Reinebo, Markus Näslund, and Thomas Parling
Despite the growing popularity of mindfulness and acceptance-based performance enhancement methods in applied sport psychology, evidence for their efficacy is scarce. The purpose of the current study is to test the feasibility and effect of a psychological training program based on Acceptance and Commitment Training (ACT) developed for ice hockey players. A controlled group feasibility designed study was conducted and included 21 elite male ice hockey players. The ACT program consisted of four, once a week, sessions with homework assignments between sessions. The results showed significant increase in psychological flexibility for the players in the training group. The outcome was positive for all feasibility measures. Participants found the psychological training program important to them as ice hockey players and helpful in their ice hockey development. Desirably, future studies should include objective performance data as outcome measure to foster more valid evidence for performance enhancement methods in applied sport psychology.
Yasuki Sekiguchi, Erica M. Filep, Courteney L. Benjamin, Douglas J. Casa, and Lindsay J. DiStefano
Clinical Scenario: Exercise in the heat can lead to performance decrements and increase the risk of heat illness. Heat acclimation refers to the systematic and gradual increase in exercise in a controlled, laboratory environment. Increased duration and intensity of exercise in the heat positively affects physiological responses, such as higher sweat rate, plasma volume expansion, decreased heart rate, and lower internal body temperature. Many heat acclimation studies have examined the hydration status of the subjects exercising in the heat. Some of the physiological responses that are desired to elicit heat acclimation (ie, higher heart rate and internal body temperature) are exacerbated in a dehydrated state. Thus, euhydration (optimal hydration) and dehydration trials during heat acclimation induction have been conducted to determine if there are additional benefits to dehydrated exercise trials on physiological adaptations. However, there is still much debate over hydration status and its effect on heat acclimation. Clinical Question: Does dehydration affect the adaptations of plasma volume, heart rate, internal body temperature, skin temperature, and sweat rate during the induction phase of heat acclimation? Summary of Findings: There were no observed differences in plasma volume, internal body temperature, and skin temperature following heat acclimation in this critically appraised topic. One study found an increase in sweat rate and another study indicated greater changes in heart rate following heat acclimation with dehydration. Aside from these findings, all 4 trials did not observe statistically significant differences in euhydrated and dehydrated heat acclimation trials. Clinical Bottom Line: There is minimal evidence to suggest that hydration status affects heat acclimation induction. In the studies that met the inclusion criteria, there were no differences in plasma volume concentrations, internal body temperature, and skin temperature. Strength of Recommendation: Based on the Oxford Centre for Evidence-Based Medicine Scale, Level 2 evidence exists.
Ui-Jae Hwang, Sung-Hoon Jung, Hyun-A Kim, Jun-Hee Kim, and Oh-Yun Kwon
Context: Electrical muscle stimulation (EMS) was designed for artificial muscle activation or superimposed training. Objectives: To compare the effects of 8 weeks of superimposed technique (ST; application of electrical stimulation during a voluntary muscle action) and EMS on the cross-sectional area of the rectus abdominis, lateral abdominal wall, and on lumbopelvic control. Setting: University research laboratory. Design: Randomized controlled trial. Participants: Fifty healthy subjects were recruited and randomly assigned to either the ST or EMS group. Intervention: The participants engaged with the electrical stimulation techniques (ST or EMS) for 8 weeks. Main Outcome Measures: In all participants, the cross-sectional area of the rectus abdominis and lateral abdominal wall was measured by magnetic resonance imaging and lumbopelvic control, quantified using the single-leg and double-leg lowering tests. Results: There were no significant differences in the cross-sectional area of the rectus abdominis (right: P = .70, left: P = .99) or lateral abdominal wall (right: P = .07, left: P = .69) between groups. There was a significant difference between groups in the double-leg lowering test (P = .03), but not in the single-leg lowering test (P = .88). There were significant differences between the preintervention and postintervention in the single-leg (P < .001) and double-leg lowering tests (P < .001). Conclusions: ST could improve lumbopelvic control in the context of athletic training and fitness.
Bridget M. Walsh, Katherine A. Bain, Phillip A. Gribble, and Matthew C. Hoch
Clinical Scenario: Patients with chronic ankle instability (CAI) commonly display lower levels of self-reported function and health-related quality of life. Several rehabilitation interventions, including manual therapy, have been investigated to help CAI patients overcome these deficits. However, it is unclear if the addition of manual therapy to exercise-based rehabilitation is more effective than exercise-based rehabilitation alone. Clinical Question: Does incorporating manual therapy with exercise-based rehabilitation improve patient-reported outcomes when compared with exercise-based rehabilitation alone? Summary of Key Findings: The literature was searched for articles that examined the difference in outcomes for patients with CAI between manual therapy with exercise-based rehabilitation and exercise-based rehabilitation alone. A total of 3 peer-reviewed randomized controlled trials were identified. Two articles demonstrated improved patient-reported outcome scores following the incorporation of manual therapy with exercise-based rehabilitation, whereas one study found no statistically significant differences between interventions. Clinical Bottom Line: The current evidence suggests that incorporating manual therapy in addition to exercised-based rehabilitation may improve patient-reported outcome scores in patients with CAI. Strength of Recommendation: In accordance with the Strength of Recommendation Taxonomy, the grade of A is recommended due to consistent evidence from high-quality studies.
Leila Ahmadnezhad, Ali Yalfani, and Behnam Gholami Borujeni
Context: People with chronic low back pain (CLBP) suffer from weaknesses in their core muscle activity and dysfunctional breathing. Inspiratory muscle training (IMT) was recently developed to treat this condition. Objectives: The present study was conducted to investigate the effect of IMT on core muscle activity, pulmonary parameters, and pain intensity in athletes with CLBP. Design: This study was designed as a single-blind, randomized, controlled trial. Setting: Clinical rehabilitation laboratory. Participants: A total of 23 male and 24 female athletes with CLBP were randomly divided into the experimental and control groups. Main Outcome Measures: The experimental group performed IMT for 8 weeks, 7 days per week and twice daily, using POWERbreathe KH1, beginning at 50% of maximum inspiratory pressure with a progressively increasing training load. The surface electromyography muscle activity of the erector spinae, multifidus, transverse abdominis and rectus abdominis, respiratory function and Visual Analogue Scale score were also measured before and after the intervention in both groups. The repeated-measures analysis of variance and 1-way analysis of covariance were further used to compare the intragroup and intergroup results following the intervention. Results: The findings of the study revealed that multifidus and transverse abdominis activity, as well as respiratory function, increased significantly in the IMT group (P < .05). Moreover, a descending trend was observed in the Visual Analogue Scale score in the experimental group (P < .05). Conclusion: The results showed that IMT can improve respiratory function, increase core muscle activity, and, consequently, reduce pain intensity in athletes with CLBP.
Wyatt D. Ihmels, Kayla D. Seymore, and Tyler N. Brown
Context: Conventional ankle prophylactics restrict harmful ankle inversion motions that lead to injury. But these existing prophylactics also limit other ankle motions, potentially leading to detriments in functional joint capacity. The ankle roll guard (ARG) may alleviate the prevailing issues of existing ankle prophylactics and prevent harmful ankle inversion, while allowing other joint motions. Objective: This technical report sought to compare the ARG’s ability to prevent ankle inversion, but not restrict other ankle motions with existing prophylactics. Design: Repeated-measures study. Setting: Motion capture laboratory. Participants: Thirty participants. Intervention: Each participant had dominant limb ankle kinematics recorded during 5 successful trials of a sudden inversion event and 30-cm drop landing task with each of 4 conditions (ARG, ASO ankle stabilizer [brace], closed-basket weave athletic tape [tape], and unbraced [control]). Main Outcome Measures: Peak ankle inversion angle, range of inversion motion (ROM), and time to peak inversion during the sudden inversion event, and ankle plantar- and dorsiflexion ROM during the drop landing were submitted to a 1-way repeated-measures analysis of variance to test the main effect of prophylaxis. Results: Participants exhibited greater inversion ROM with control compared with tape (P = .001), and greater plantar- and dorsiflexion ROM with ARG and control compared with brace (P = .02, P = .001) and tape (P = .02, P < .001). It took significantly longer to reach peak ankle inversion with brace and tape compared with ARG (P < .001, P = .001) and control (P = .01, P = .01). No significant difference in peak ankle inversion was observed between any condition (P > .05). Conclusion: The ARG may prevent ankle inversion angles where injury is thought to occur (reportedly >41°), but is less restrictive than existing prophylactics. The less restrictive ARG may make its use ideal during rehabilitation as it allows ankle plantar- and dorsiflexion motions, while preventing inversion related to injury.
Kenneth Färnqvist, Stephen Pearson, and Peter Malliaras
Context: Exercise is seen as the most evidence-based treatment for managing tendinopathy and although the type of exercise used to manage tendinopathy may induce adaptation in healthy tendons, it is not clear whether these adaptations occur in tendinopathy and if so whether they are associated with improved clinical outcomes. Objective: The aim of the study was to synthesize available evidence for adaptation of the Achilles tendon to eccentric exercise and the relationship between adaptation (change in tendon thickness) and clinical outcomes among people with Achilles tendinopathy. Evidence Acquisition: The search was performed in September 2018 in several databases. Studies investigating the response (clinical outcome and imaging on ultrasound/magnetic resonance imaging) of pathological tendons (tendinopathy, tendinosis, and partial rupture) to at least 12 weeks of eccentric exercise were included. Multiple studies that investigated the same interventions and outcome were pooled and presented in effect size estimates, mean difference, and 95% confidence intervals if measurement scales were the same, or standard mean difference and 95% confidence intervals if measurements scales were different. Where data could not be pooled the studies were qualitatively synthesized based on van Tulder et al. Evidence Synthesis: Eight studies met the inclusion and exclusion criteria and were included in the review. There was strong evidence that Achilles tendon thickness does not decrease in parallel with improved clinical outcomes. Conclusions: Whether a longer time to follow-up is more important than the intervention (ie, just the time per se) for a change in tendon thickness remains unknown. Future studies should investigate whether exercise (or other treatments) can be tailored to optimize tendon adaptation and function, and whether this relates to clinical outcomes.