Purpose: The authors evaluated changes in intermuscular coherence (IMC) of orofacial and speech breathing muscles across phase of speech production in healthy younger and older adults. Method: Sixty adults (30 younger = M: 26.97 year; 30 older = M: 66.37 year) read aloud a list of 40 words. IMC was evaluated across phase: preparation (300 ms before speech onset), initiation (300 ms after onset), and total execution (entire word). Results: Orofacial IMC was lowest in the initiation, higher in preparation, and highest for the total execution phase. Chest wall IMC was lowest for the preparation and initiation and highest for the total execution phase. Despite age-related differences in accuracy, neuromuscular modulation for phase was similar between groups. Conclusion: These results expand our knowledge of speech motor control by demonstrating that IMC is sensitive to phase of speech planning and production.
Alesha Reed, Jacqueline Cummine, Neesha Bhat, Shivraj Jhala, Reyhaneh Bakhtiari, and Carol A. Boliek
Jeffrey B. Driban and Patrick O. McKeon
Jack P. Callaghan
Samuel C. Fischer, Darren Q. Calley, and John H. Hollman
Clinical Scenario : Low back pain is a common condition for the general population with 29% of adults having low back pain within the last 3 months. A deadlift is described as a free weight exercise in which a barbell is lifted from the floor in a continuous motion by extending the knees and hips. For those without low back pain, the deadlift was found to have the highest muscle activation of paraspinal musculature compared with other exercises. There are a limited number of studies that investigate the usefulness of incorporating deadlifts as part of a rehabilitation program for low back pain. Clinical Question: For those who live with low back pain, is an exercise routine that includes a deadlift a viable treatment option to improve pain and/or function? Summary of Key Findings: The literature search yielded 3 total studies meeting the inclusion and exclusion criteria: 1 randomized control trial, 1 secondary analysis of a randomized control trial, and 1 cohort study. Exercise programs that include deadlifts can yield improvements in both pain and function for those living with low back pain but were not found to be more beneficial than low load motor control exercises. Those with lower pain levels and higher baseline lumbar extension strength may be most appropriate to participate in an exercise program that includes deadlifts. Further research is needed to compare exercise programs that include deadlifts to other interventions for those living with low back pain. Clinical Bottom Line: There is minimal evidence that exercise programs that included deadlifts are a clinically effective option for the treatment of low back pain for both pain scores and functional outcome measures. Strength of Recommendation: Level B evidence exists that exercise programs that include deadlifts are a clinically effective option for the treatment of low back pain for both pain scores and functional outcome measures.
Scott Benson Street, Matthew Rawlins, and Jason Miller
Clinical Scenario: Ankle fractures are a frequent occurrence, and they carry the potential for syndesmosis injury. The syndesmosis is important to the structural integrity of the ankle joint by maintaining the proximity of the tibia, fibula, and talus. Presently, the gold standard for treating an ankle syndesmosis injury is to insert a metallic screw through the fibula and into the tibia. This technique requires a second intervention to remove the hardware, but also carries an inherent risk of breaking the screw during rehabilitation. Another fixation technique, the Tightrope™, has gained popularity in treating ankle syndesmosis injuries. The TightRope™ involves inserting Fiberwire® through the tibia and fibula, which allows for stabilization of the ankle mortise and normal range of motion. Clinical Question: In patients suffering from ankle syndesmosis injuries, is the Tightrope™ ankle syndesmosis fixation system more effective than conventional screw fixation at improving return to work, pain, and patient-reported outcome measures? Summary of Key Findings: Five studies were selected to be critically appraised. The PEDro checklist was used to score 2 randomized control trials, and the Downs & Black checklist was used to score the cohort study on methodology and consistency. Two systematic reviews were also appraised. All 5 articles demonstrated support for using the TightRope™ fixation. Clinical Bottom Line: There is moderate evidence to support the use of the TightRope™ syndesmosis fixation system, as it provides both clinician- and patient-reported outcomes that are similar to those using the conventional metallic screw, with a shortened time to recover and return to activity. Strength of Recommendation: Grade A evidence exists in support of using the TightRope™ fixation system in place of the metallic screw following ankle syndesmosis injury.
Karin Weman Josefsson
Sweden has adopted a somewhat different approach to handle the corona pandemic, which has been widely debated both on national and international levels. The Swedish model involves more individual responsibility and reliance on voluntary civic liability than law enforcement, while common measures in other countries are based on more controlling strategies, such as restrictive lockdowns, quarantines, closed borders, and mandatory behavior constraints. This commentary aims to give a brief overview of the foundations of the Swedish model as well as a discussion on how and why it has been adopted in the Swedish society based on Swedish legislations, culture, and traditions. Finally, perspectives on how the Swedish model could be connected to the tenets of self-determination theory will be discussed.
Manuel J. Escalona, Daniel Bourbonnais, Michel Goyette, Damien Le Flem, Cyril Duclos, and Dany H. Gagnon
The effects of walking speeds on lower-extremity muscle synergies (MSs) were investigated among 20 adults who walked 20 m at SLOW (0.6 ± 0.2 m/s), natural (NAT; 1.4 ± 0.1 m/s), and FAST (1.9 ± 0.1 m/s) speeds. Surface electromyography of eight lower-extremity muscles was recorded before extracting MSs using a nonnegative matrix factorization algorithm. Increasing walking speed tended to merge MSs associated with weight acceptance and limb deceleration, whereas reducing walking speed does not change the number and composition of MSs. Varying gait speed, particularly decreasing speed, may represent a gait training strategy needing additional attention given its effects on MSs.
Daniella M. DiGuglielmo, Mireille E. Kelley, Mark A. Espeland, Zachary A. Gregory, Tanner D. Payne, Derek A. Jones, Tanner M. Filben, Alexander K. Powers, Joel D. Stitzel, and Jillian E. Urban
To reduce head impact exposure (HIE) in youth football, further understanding of the context in which head impacts occur and the associated biomechanics is needed. The objective of this study was to evaluate the effect of contact characteristics on HIE during player versus player contact scenarios in youth football. Head impact data and time-synchronized video were collected from 4 youth football games over 2 seasons in which opposing teams were instrumented with the Head Impact Telemetry (HIT) System. Coded contact characteristics included the player’s role in the contact, player speed and body position, contact height, type, and direction, and head contact surface. Head accelerations were compared among the contact characteristics using mixed-effects models. Among 72 instrumented athletes, 446 contact scenarios (n = 557 impacts) with visible opposing instrumented players were identified. When at least one player had a recorded impact, players who were struck tended to have higher rotational acceleration than players in striking positions. When both players had a recorded impact, lighter players and taller players experienced higher mean head accelerations compared with heavier players and shorter players. Understanding the factors influencing HIE during contact events in football may help inform methods to reduce head injury risk.
Bin Chen, Lifen Liu, Lincoln Bin Chen, Xianxin Cao, Peng Han, Chenhao Wang, and Qi Qi
Context: Measuring isometric shoulder rotational strength is clinically important for evaluating motor disability in athletes with shoulder injuries. Recent evidence suggests that handheld dynamometry may provide a low-cost and portable method for the clinical assessment of isometric shoulder strength. Objective: To investigate the concurrent validity and the intrarater and interrater reliability of handheld dynamometry for measuring isometric shoulder rotational strength. Design: Cross-sectional study. Setting: Biomechanics laboratory. Participants: Thirty-nine young, healthy participants. Main Outcome Measures: The peak isometric strength of the internal rotators and external rotators, measured by handheld dynamometry (in newton) and isokinetic dynamometry (in newton meter). Interventions: Maximal isometric shoulder rotational strength was measured as participants lay supine with 90° shoulder abduction, neutral rotation, 90° elbow flexion, and forearm pronation. Measurements were performed independently by 2 different physiotherapists and in 3 different sessions to evaluate interrater and intrarater reliability. The data obtained by handheld dynamometry were compared with those obtained by isokinetic testing to evaluate concurrent validity. Results: The intraclass correlation coefficients for interrater reliability in measuring maximum isometric shoulder external and internal rotation strength were .914 (95% confidence interval [CI], .842–.954) and .842 (95% CI, .720–.914), respectively. The intrarater reliability values of the method for measuring maximal shoulder external and internal rotation strength were 0.865 (95% CI, 0.757–0.927) and 0.901 (95% CI, 0.820–0.947), respectively. The Pearson correlation coefficients between the handheld and isokinetic dynamometer measurements were .792 (95% CI, .575–.905) for external rotation strength and .664 (95% CI, .419–.839) for internal rotation strength. Conclusions: The handheld dynamometer showed good to excellent reliability and moderate to good validity in measuring maximum isometric shoulder rotational strength. Therefore, handheld dynamometry could be acceptable for health and sports professionals in field situations to evaluate maximum isometric shoulder rotational strength.