Context: Imbalances in upper-extremity soft tissue stiffness may play a role in the development of shoulder and elbow musculoskeletal injuries in tennis players. Ultrasound shear wave elastography provides quantifiable and specific data regarding muscle stiffness. The purpose of this study was to compare tendon and muscle stiffness in healthy tennis players to nontennis players. Design: Cross-sectional study. Methods: The shear wave modulus, measured in kilopascals, was obtained for the dominant pectoralis major, pectoralis minor, and common wrist-extensor tendon using 2-dimensional shear wave elastography ultrasound imaging (GE Logiq S8, L9 linear transducer). Independent t test was run to compare age, body mass index, and the activity index score between both groups. Within-day intrarater reliability was assessed using a within-examiner intraclass correlation coefficients (ICC [3, 1]) with 95% confidence intervals. A multivariate general linear model was run to compare the mean differences between the tennis and nontennis players for each of the soft tissues. Results: Twenty-six individuals (13 tennis players and 13 nontennis players) were recruited. Within-day ICCs were very good (ICC > .78 for the pectoralis musculature) and excellent (ICC > .94 for the common wrist extensor). Common extensor tendon stiffness was significantly higher in tennis players compared to nontennis players (mean difference = 114.8 [61.8], confidence interval, −22.8 to 252.5 kPa for the dominant arm [P = .039]). Mean pectoralis major and minor stiffness differences were not significant (P > .214). Conclusions: Common wrist-extensor stiffness in healthy recreational tennis players is higher than those who do not play tennis. Therefore, clinicians may need to facilitate a greater soft tissue stiffness response with resistance training when rehabilitating recreational tennis players as compared to those not playing tennis. Additional normative data on a larger sample of recreational tennis players should be collected.
Common Wrist-Extensor Tendon and Pectoralis Muscle Stiffness in Healthy Recreational Tennis Players
Joseph M. Day and Harold Merriman
The Efficiency of Respiratory Exercises in Rehabilitation of Low Back Pain: A Systematic Review and Meta-Analysis
Haiting Zhai, Liqing Zhang, JiXiang Xia, and Cheng Li
Background: Low back pain (LBP) is a common musculoskeletal disorder, and respiratory exercise is considered a nonsurgical management method. Therefore, this systematic review and meta-analysis aims to estimate the results of randomized controlled trials on the effect of respiratory training in reducing LBP and its dose relationship. Methods: The present study was conducted from January 2020 to January 2022, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (2020). Relevant studies were searched in multiple databases including PubMed, Web of Science, the Cochrane Library, EBSCO, Scopus, ScienceDirect, Wan Fang and China Knowledge Network, ClinicalTrials.gov, and Google Scholar, using a combination of MeSH/Emtree terms and free-text words. The heterogeneity of the studies was assessed using the I 2 statistic. Results: A total of 14 publications were included in the meta-analysis, with a total sample size of 698 individuals, aged 60–80 years. Respiratory exercise was effective in relieving LBP (standardized mean difference = −0.87, P < .00001) and improving physical disability (standardized mean difference = −0.79, P < .00001). The type of breathing and the total duration of breathing exercises were found to be the source of heterogeneity in this study by subgroup analysis. Subgroup analysis revealed that the most significant effect sizes of breathing resistance exercise to reduce LBP and the most significant effect sizes of breathing relaxation techniques to alleviate physical disability were performed 3 to 5 times per week and period >4 weeks. Respiratory exercise reducing LBP and improving functional disability was most effective when the total duration of the intervention was >500 minutes. Funnel plots showed that the results of the 2 overall studies were reliable without publication bias. Conclusions: Respiratory exercise can effectively reduce LBP and improve physical disability. Therefore, these exercises can be regarded as a part of a LBP management plan. We recommend an exercise program with 30 to 50 minutes, 3 to 5 times per week, and >4 weeks of breathing resistance exercise program as the most effective for treating LBP.
Effects of Blood Flow Restriction on Balance Performance During Dynamic Balance Exercises in Individuals With Chronic Ankle Instability
Krista Clark, Justin Trickett, Luke Donovan, Jordan Dawson, and John Goetschius
Context: Blood flow restriction (BFR) is a rehabilitation tool which may introduce a constraint, similar to muscle fatigue, that challenge patients’ sensorimotor system during balance exercises. The purpose of our study was to examine whether adding BFR to dynamic balance exercises produced a decrease in balance performance and an increase in ratings of perceived exertion and instability in individuals with chronic ankle instability (CAI) compared with dynamic balance exercises without BFR. Designs: Crossover design. Methods: Our sample included N = 25 young adults with a history of CAI. Participants completed 2 laboratory visits. At each visit, participants completed 4 sets (30×-15×-15×-15×) of dynamic balance exercises, performed similar to the modified star excursion balance test (SEBT), once with BFR and once with control (no BFR) conditions. We measured composite SEBT scores at baseline and during the final repetitions of each set of balance exercise (sets 1–4). We also measured ratings of perceived exertion and instability following each balance exercise set. Results: We observed no difference in composite SEBT scores between conditions at baseline; however, composite SEBT scores were significantly lower during all balance exercises sets 1 to 4 with the BFR condition compared with control. During the BFR condition, composite SEBT scores were significantly lower during all balance exercise sets compared with baseline. During the control condition, composite SEBT scores did not significantly change between baseline and each balance exercise set. Ratings of perceived exertion and instability scores were significantly greater in the BFR group compared with the control group during all balance exercise sets. Conclusions: Individuals with CAI demonstrated lower composite SEBT scores and greater perceived instability and exertion during dynamic balance exercise with BFR compared to without BFR. BFR introduced a novel muscle fatigue constraint during dynamic balance exercises in individuals with CAI. Additional research is needed to determine if adding BFR to balance training could improve clinical outcomes in CAI patients.
Relationship Between Knee Frontal Plane Projection Angle and Lower Limb Muscle Activity in Female Athletes
Luis Llurda-Almuzara, Max Canet-Vintró, Carlos López-de-Celis, Albert Perez-Bellmunt, Noé Labata-Lezaun, Ramón Aiguadé-Aiguadé, and Jacobo Rodriguez-Sanz
Context: Anterior cruciate ligament injuries are directly related to the control of dynamic knee valgus in the landing of a jump, and this is mainly due to the correct activation and neuromuscular function of the lower-extremity muscles. The aim of the study is to assess the relationship between lower limb muscle activity during a single-legged drop jump and knee frontal plane projection angle (FPPA). Design: A correlation study. Methods: Thirty healthy collegiate female athletes were included in the study. Main outcomes measures were peak knee FPPA and muscle activity (% of maximal voluntary isometric contraction). Peak knee FPPA during a single-legged drop jump test was identified using a 2-dimensional motion analysis system. Muscle activity was assessed using a surface electromyograph for gluteus maximus, gluteus medius, biceps femoris, semitendinosus, vastus medialis quadriceps, vastus lateralis quadriceps, medial gastrocnemius, and lateral gastrocnemius. All variables were assessed for both dominant and nondominant limbs. A correlation analysis between peak knee FPPA and muscle activity was performed. Statistical significance was set at P <.05. Results: A mean peak knee FPPA of 14.52° and 13.38° was identified for dominant and nondominant limb single-legged drop jump test, respectively. Muscle activity (% of maximal voluntary isometric contraction) for muscles assessed ranged from 43.97% to 195.71% during the single-legged drop jump test. The correlation analysis found no significant correlation between any of the muscles assessed and peak knee FPPA during the single-legged drop jump test (Pearson coefficient between −.3 and .1). Conclusions: There is no association between muscle activity from the lower limb muscles and the knee FPPA during a single-legged drop jump in female athletes. Thus, different muscle properties should be assessed in order to understand such an important movement as the knee FPPA during a jump.
The Influence of Race on Time to Symptom Resolution Following Sport Concussion in Collegiate Athletes
Angelina M. Domena, Daniel J. Rosenblum, Catherine C. Donahue, and Jacob E. Resch
Context: Race has been shown to influence computerized neurocognitive test scores, motor function test scores, and reported symptomology following sport-related concussion (SRC). However, the effect race may have on recovery time following SRC remains unknown. The objective of this study was to determine the influence of race on days until symptom free from SRC in NCAA Division 1 collegiate athletes. Design: Prospective cohort study. Methods: Participants were Black (n = 53 [28% female]) and White (n = 150 [43.3% female]) who were on average 19.0 (1.21) and 20.2 (1.3) years of age, respectively. Data were collected from the 2015–2016 to 2020–2021 collegiate sport seasons. Participants were evaluated before and after an SRC at empirically derived time points. The primary outcome measure was time until symptom free (days). Additional outcomes included baseline and postinjury Immediate Postconcussion Assessment and Cognitive Test and Sensory Organization Test (SOT) scores. A Mann–Whitney U test compared days to symptom free between groups. Immediate Postconcussion Assessment and Cognitive Test and SOT outcome scores were analyzed using a 2 (group) × 2 (time) analysis of variance. Results: White participants had a longer median recovery time (9 d) to symptom free compared with Black participants (6 d [P = .04]). Statistically significant differences were observed between Black 87.3 (9.84) and White 90.4 (8.30) groups for Immediate Postconcussion Assessment and Cognitive Test’s verbal memory composite score (P = .03). Postinjury, White participants scored significantly higher 44.5 (5.63) on visual motor speed compared with Black participants (42.4 (5.90) [P = .02]). Within-group SOT differences between baseline and postinjury testing were observed in both groups (all P < .001). Conclusions: Black collegiate athletes achieved symptom resolution sooner than White athletes. We did not explore underlying sociocultural factors such as socioeconomic status or previous concussion education, which may have influenced our results. Future studies should explore factors that may contextualize these findings.
Preventing Suicide and Promoting Mental Health Among Student-Athletes From Diverse Backgrounds
Karrie L. Hamstra-Wright, John E. Coumbe-Lilley, and Eduardo E. Bustamante
Suicide and contributing mental health conditions in athletes are shared concerns within health care and society at large. This commentary focuses on suicide risk among athletes and the role of sports medicine professionals in preventing suicide and promoting mental health. In this commentary, we draw on the scientific literature and our clinical experiences to pose and answer these questions: Does suicide risk among athletes vary by sociodemographic factors (eg, sex, gender, race/ethnicity, family income, sexual orientation) or if injured? Do sociodemographic differences influence access to and benefits from services among athletes? How do I know my athletes are at risk for suicide? What do I do if one of my athletes shares with me that they have considered suicide? Within our commentary, we review the current literature and clinical practices regarding these questions and close with actionable suggestions and recommendations for future directions.
Volume 33 (2024): Issue 2 (Feb 2024)
Automated Versus Traditional Scoring Agreeability During the Balance Error Scoring System
Amelia S. Bruce Leicht, James T. Patrie, Mark A. Sutherlin, Madeline Smart, and Joe M. Hart
Context: The Balance Error Scoring System (BESS) is a commonly used clinical tool to evaluate postural control that is traditionally performed through visual assessment and subjective evaluation of balance errors. The purpose of this study was to evaluate an automated computer-based scoring system using an instrumented pressure mat compared to the traditional human-based manual assessment. Design: A descriptive cross-sectional study design was used to evaluate the performance of the automated versus human BESS scoring methodology in healthy individuals. Methods: Fifty-one healthy active participants performed BESS trials following standard BESS procedures on an instrumented pressure mat (MobileMat, Tekscan Inc). Trained evaluators manually scored balance errors from frontal and sagittal plane video recordings for comparison to errors scored using center of force measurements and an automated scoring software (SportsAT, version 2.0.2, Tekscan Inc). A linear mixed model was used to determine measurement discrepancies across the 2 methods. Bland–Altman analyses were conducted to determine limit of agreement for the automated and manual scoring methods. Results: Significant differences between the automated and manual errors scored were observed across all conditions (P < .05), excluding bilateral firm stance. The greatest discrepancy between scoring methods was during the tandem foam stance, while the smallest discrepancy was during the tandem firm stance. Conclusion: The 2 methods of BESS scoring are different with wide limits of agreement. The benefits and risks of each approach to error scoring should be considered when selecting the most appropriate metric for clinical use or research studies.
The Effect of Active Release Technique on Hamstring Extensibility: A Critically Appraised Topic
Mikala Palermo, Sierra Reich, and Mika Rives
Clinical Scenario: Hamstring extensibility plays a significant role in maintaining postural alignment essential for a functional musculoskeletal system. When hamstring extensibility is lacking, individuals are placed at a higher risk for developing various lumbar spine, pelvis, knee, and foot dysfunctions. Limited hamstring extensibility is common, occurring in as much as 40% of college students and 86% of the adult population. Therefore, it is essential to maintain hamstring extensibility, which can be aided by understanding intervention effectiveness for improving flexibility. Purpose: To critically appraise the literature on the effectiveness of Active Release Technique (ART) for the treatment of hamstring extensibility deficits. Clinical Question: What is the effect of ART in a healthy population with or without hamstring extensibility deficits? Summary of Key Findings: Three studies were included for critical appraisal. Two studies concluded a single treatment session of ART that individuals possessing limited straight leg raise range of motion experienced improved active knee extension, popliteal angle, and sit-and-reach test measures. In the third study, a single session of ART was effective at improving hamstring extensibility in males without hamstring extensibility dysfunction. Clinical Bottom Line: Based on the current level 1 and level 3 evidence, ART may be an effective treatment to produce acute increases in hamstring extensibility. Future research is still needed. Strength of Recommendation: Level B evidence exists to support the use of ART to improve hamstring extensibility in the healthy population.