This study investigated the sensorimotor strategies for dynamic balance control in individuals with stroke by restricting sensory input that might influence task accomplishment. Sit-to-stand movements were performed with restricted vision by participants with hemiparesis and healthy controls. The authors evaluated the variability in the position of participants’ center of mass and velocity, and the center-of-pressure position, in each orthogonal direction at the lift-off point. When vision was restricted, the variability in the mediolateral center-of-pressure position decreased significantly in individuals with hemiparesis, but not in healthy controls. Participants with hemiparesis adopted strategies that explicitly differed from those used by healthy individuals. Variability may be decreased in the direction that most requires accuracy. Individuals with hemiparesis have been reported to have asymmetrical balance deficits, and that meant they had to prioritize mediolateral motion control to prevent falling. This study suggests that individuals with hemiparesis adopt strategies appropriate to their characteristics.
Yuko Kuramatsu, Yuji Yamamoto, and Shin-Ichi Izumi
Patrick O. McKeon and Jennifer M. Medina McKeon
Sergio Jiménez-Rubio, Archit Navandar, Jesús Rivilla-García, Víctor Paredes-Hernández, and Miguel-Ángel Gómez-Ruano
Context: Although there are multiple, validated return-to-play programs following hamstring strain injuries, no studies have evaluated their changes in match performance parameters. Objectives: The aim of this study was twofold as follows: (1) to determine the changes in match-based physical performance parameters in professional soccer players before and after sustaining a hamstring strain injury and undergoing a soccer-specific rehabilitation program and (2) to observe the progress of these performance parameters 6 to 10 weeks after the player returned from injury. Design: Prospective, quasi-experimental longitudinal study. Setting: Soccer playing and training grounds. Participants: Nineteen players suffering a hamstring strain injury from 2 male professional teams playing in the Spanish professional football league (La Liga) were followed during the 2015–2016, 2016–2017, and 2017–2018 seasons. Intervention: Participation in on-field training program following a hamstring injury. Main Outcome Measures: Match global positioning system data were collected in the following stages: prior to injury (PRE), after return to play (RTP), program, and 6 to 10 weeks following RTP (C2). Peak velocities and distances ran at sprint velocities showed most likely improvements in C2 versus PRE, and very likely improvements in RTP versus PRE. Results: The distances ran at high and very high intensities, the average velocity, and work-to-rest ratio showed very likely improvements in C2 versus RTP and likely improvements in RTP versus PRE. Likely improvements were observed for all variables in C2 versus RTP. The authors’ results showed an improvement of physical performance during competitive match after RTP, compared with PRE. There was a steady progression in the progress, and in 8 months following RTP, there was no injury reported in the players. Conclusions: The current findings may indicate that the hamstring muscle complex not only recovered completely from the injury but could also withstand a greater training and match load reducing the risk of reinjury.
Xin Fu, Patrick Shu-hang Yung, Chun Cheong Ma, and Hio Teng Leong
Context: Rotator cuff tendinopathy is one of the most frequently reported shoulder injuries in athletes of overhead sports. Abnormal scapular kinematics has been proposed as one of the contributing factors of rotator cuff tendinopathy in overhead athletes. Objectives: To review the literature on 3-dimensional scapular kinematics in overhead athletes with and without rotator cuff tendinopathy. Evidence Acquisition: Electronic databases (Cochrane Library, MEDLINE, Embase, and PubMed) were searched from inception to September 2017. In addition, the reference lists of the articles that met the inclusion criteria were also searched. We included studies that compared the changes in 3-dimensional scapular kinematics in athletes with and without rotator cuff tendinopathy. Two reviewers independently examined the quality of studies by using the modified Downs and Black checklist. Evidence Synthesis: A total of 9 studies (a total of 332 athletes, mean age 23.41 [2.62] y) were included in the final analysis. The methodological quality was low (modified Downs and Black checklist = 9/15). Our findings showed a consistent pattern of increased scapular anterior tilting and internal rotation in the dominant shoulders than the nondominant shoulders of athletes who participated in overhead sports. Athletes of overhead sports seem to demonstrate an increase in scapular upward rotation during arm elevation when compared with nonathlete individuals. However, there is no consensus on the scapular kinematics pattern in athletes with rotator cuff tendinopathy when compared with healthy controls. Conclusion: Findings demonstrated that changes in scapular kinematics were observed in overhead athletes. However, all the included studies were cross-sectional studies with small sample size and diverse sports participation, whether changes in scapular kinematics may contribute to rotator cuff tendinopathy in overhead athletes warrants more high-quality prospective studies.
Damla Karabay, Yusuf Emük, and Derya Özer Kaya
Context: Selective strengthening of scapular stabilizers is one of the emphases of the recent literature. Closed kinetic chain (CKC) exercises are used extensively in shoulder rehabilitation. However, a limited number of studies have reported scapular muscle ratios during CKC exercises. Objectives: To determine the CKC exercises producing the optimal ratios of the scapular stabilizer muscles in healthy shoulders. Evidence Acquisition: A systematic search within PubMed, Embase, CINAHL Plus, and SPORTDiscus with Full Text and ULAKBIM National Medical Database was performed up to January 2018. Studies were selected according to the predetermined criteria. If the pooled mean ratios (upper trapezius [UT]/middle trapezius [MT], UT/lower trapezius [LT], and UT/serratus anterior [SA]), which were calculated from the percentage of maximum voluntary contractions of muscles, were <0.60, these exercises were considered as ideal for higher activation of the MT, LT, and SA than the UT. Evidence Synthesis: The search identified 1284 studies, and 29 observational studies were included for review. Seventy-nine CKC exercises were determined. Four exercises for the MT, 9 for the LT, and 59 for the SA were identified from the articles as being optimal exercises to activate the specified muscle more than the UT. Conclusions: This review identified optimal CKC exercises that provide good ratios between the MT, LT, and SA with the UT. Most exercises have optimal UT/SA ratios, but some exercises performed on unstable surfaces may lead to excessive activation of the UT relative to the SA. For the UT/MT, the isometric low row, inferior glide, and half supine pull-up with slings are the ideal exercises. Isometric one-hand knee push-up variations seem to be the best choice for the UT/LT. The results suggest that many CKC exercises may be utilized to enhance scapular muscle balance when rehabilitating shoulder pathology.
Maja Zamoscinska, Irene R. Faber, and Dirk Büsch
Clinical Scenario: Reduced bone mineral density (BMD) is a serious condition in older adults. The mild form, osteopenia, is often a precursor of osteoporosis. Osteoporosis is a pathological condition and a global health problem as it is one of the most common diseases in developed countries. Finding solutions for prevention and therapy should be prioritized. Therefore, the critically appraised topic focuses on strength training as a treatment to counteract a further decline in BMD in older adults. Clinical Question: Is strength training beneficial in increasing BMD in older people with osteopenia or osteoporosis? Summary of Key Findings: Four of the 5 reviewed studies with the highest evidence showed a significant increase in lumbar spine BMD after strength training interventions in comparison with control groups. The fifth study confirmed the maintenance of lumbar spine density due to conducted exercises. Moreover, 3 reviewed studies revealed increasing BMD at the femoral neck after strength training when compared with controls, which appeared significant in 2 of them. Clinical Bottom Line: The findings indicate that strength training has a significant positive influence on BMD in older women (ie, postmenopausal) with osteoporosis or osteopenia. However, it is not recommended to only rely on strength training as the increase of BMD may not appear fast enough to reach the minimal desired values. A combination of strength training and supplements/medication seems most adequate. Generalization of the findings to older men with reduced BMD should be done with caution due to the lack of studies. Strength of Recommendation: There is grade B of recommendation to support the validity of strength training for older women in postmenopausal phase with reduced BMD.
Neal R. Glaviano, Ashley N. Marshall, L. Colby Mangum, Joseph M. Hart, Jay Hertel, Shawn Russell, and Susan Saliba
Context: Patellofemoral pain (PFP) is a challenging condition, with altered kinematics and muscle activity as 2 common impairments. Single applications of patterned electrical neuromuscular stimulation (PENS) have improved both kinematics and muscle activity in females with PFP; however, the use of PENS in conjunction with a rehabilitation program has not been evaluated. Objective: To determine the effects of a 4-week rehabilitation program with PENS on lower-extremity biomechanics and electromyography (EMG) during a single-leg squat (SLS) and a step-down task (SDT) in individuals with PFP. Study Design: Double-blinded randomized controlled trial. Setting: Laboratory. Patients of Other Participants: Sixteen females with PFP (age 23.3 [4.9] y, mass 66.3 [13.5] kg, height 166.1 [5.9] cm). Intervention: Patients completed a 4-week supervised rehabilitation program with or without PENS. Main Outcome Measures: Curve analyses for lower-extremity kinematics and EMG activity (gluteus maximus, gluteus medius, vastus medialis oblique, vastus lateralis, biceps femoris, and adductor longus) were constructed by plotting group means and 90% confidence intervals throughout 100% of each task, before and after the rehabilitation program. Mean differences (MDs) and SDs were calculated where statistical differences were identified. Results: No differences at baseline in lower-extremity kinematics or EMG were found between groups. Following rehabilitation, the PENS group had significant reduction in hip adduction between 29% and 47% of the SLS (MD = 4.62° [3.85°]) and between 43% and 69% of the SDT (MD = 6.55° [0.77°]). Throughout the entire SDT, there was a decrease in trunk flexion in the PENS group (MD = 10.91° [1.73°]). A significant decrease in gluteus medius activity was seen during both the SLS (MD = 2.77 [3.58]) and SDT (MD = 4.36 [5.38]), and gluteus maximus during the SLS (MD = 1.49 [1.46]). No differences were seen in the Sham group lower-extremity kinematics for either task. Conclusion: Rehabilitation with PENS improved kinematics in both tasks and decreased EMG activity. This suggests that rehabilitation with PENS may improve muscle function during functional tasks.
Cody R. Butler, Kirsten Allen, Lindsay J. DiStefano, and Lindsey K. Lepley
Clinical Scenario: Anterior cruciate ligament (ACL) tear is a devastating knee injury with negative long-term consequences, such as early-onset knee osteoarthritis, biomechanical compensations, and reduced physical activity. Significant reduction in physical activity is a powerful indicator of cardiovascular (CV) disease; therefore, those with a history of ACL injury may be at increased risk for CV disease compared with noninjured individuals. Focused Clinical Question: Do individuals with a history of ACL injury demonstrate negative CV changes compared with those without a history of ACL injury? Summary of Key Findings: Three articles met the inclusion criteria and investigated CV changes after ACL injury. Both cross-sectional studies compared participants with ACL injury with matched controls. Bell et al compared time spent in moderate to vigorous physical activity and step count, whereas Almeida et al compared maximum rate of oxygen consumption, ventilatory thresholds, isokinetic quadriceps strength, and body composition. Collectively, both quantitative studies found that individuals with a history of ACL injury had less efficient CV systems compared with matched controls and/or preoperative data. Finally, a qualitative study of 3506 retired National Football League athletes showed an increased rate of arthritis and knee replacement surgery after an ACL injury when compared with other retired National Football League members, in addition to a >50% increased rate of myocardial infarction. Clinical Bottom Line: A history of ACL injury is a source of impaired physical activity. Preliminary data indicate that these physical activity limitations negatively impair the CV system, and individuals with a history of ACL injury demonstrate lower maximum oxygen consumption, self-reported disability, and daily step count compared with noninjured peers. These complications support the need for greater emphasis on CV wellness. Strength of Recommendation: Consistent findings from 2 cross-sectional studies and 1 survey study suggest level IIB evidence to support that ACL injury is associated with negative CV health.
Marcie Fyock, Nelson Cortes, Alex Hulse, and Joel Martin
Clinical Scenario: Patellofemoral pain (PFP) is a common knee injury in recreational adult runners, possibly caused by faulty mechanics. One possible approach to reduce this pain is to retrain the runner’s gait. Current research suggests that no definitive gold standard treatment for PFP exists. Gait retraining utilizing visual feedback may reduce PFP in both the short and long term. Clinical Question: In adult runners diagnosed with PFP, does gait retraining with real-time visual feedback lead to a decrease in pain? Summary of Key Findings: A literature search was performed; 3 relevant studies utilizing gait retraining with visual feedback, pain level as an outcome measure, and follow-up measures of at least 1 month after the intervention were included. All the included studies reported a decrease in short- and long-term pain for participants following visual feedback gait retraining. In addition, biomechanical measures related to PFP, including peak hip adduction angle and the angle of contralateral pelvic drop, improved after the completion of the intervention. Clinical Bottom Line: There is level 2 evidence supporting the implementation of 8 sessions over 2 weeks of visual feedback gait retraining as a means of treating patients diagnosed with PFP. Based on current available evidence, clinicians should identify faulty mechanics of patients and implement a protocol of increasing real-time visual feedback over the first 4 sessions and decreasing visual feedback over the final 4 sessions. Strength of Recommendation: Level 2.