Context: This study aimed to examine the differences in electromyographic (EMG) activity of the biceps femoris long head (BFlh) and semitendinosus (ST) muscles, break-point angle (BPA), and the angle at peak BFlh EMG activity between bilateral and unilateral Nordic hamstring exercise (NHE) on a sloped platform. Design: This study was designed as a case-control study. Methods: Fourteen men participated in the study. The participants initially performed maximum voluntary isometric contraction (MVIC) on the prone leg curl to normalize the peak hamstring EMG amplitude as the %MVIC. Then, participants were randomized to perform the following 3 variations of NHE: bilateral (N40) or unilateral (N40U) NHE with a platform angle of 40°, and unilateral NHE with a platform angle of 50° (N50U). The EMG activities of the BFlh and ST and the knee flexion angle during the NHE variations were recorded to calculate the EMG activity of the BFlh and ST in terms of the %MVIC, the angle at peak BFlh EMG, and BPA. Results: The BFlh %MVIC was significantly higher in N40U (P < .05) and N50U (P < .05) than in N40. A significant difference in BFlh %MVIC and ST %MVIC was observed between N40U (P < .05) and N50U (P < .05). The mean values of BPA and the angle at peak BFlh EMG were <30° for all NHE variations. Conclusions: In the late swing phase of high-speed running, BFlh showed higher EMG activity; thus, unilateral NHE may be a specific hamstring exercise for hamstring injury prevention.
Toshiaki Soga, Taspol Keerasomboon, Kei Akiyama, and Norikazu Hirose
Eugene Tee, Jack Melbourne, Larissa Sattler, and Wayne Hing
Context: Acute lateral ankle sprain (LAS) is a common injury in athletes and is often associated with decreased athletic performance and, if treated poorly, can result in chronic ankle issues, such as instability. Physical performance demands, such as cutting, hopping, and landing, involved with certain sport participation suggests that the rehabilitation needs of an athlete after LAS may differ from those of the general population. Objective: To review the literature to determine the most effective rehabilitation interventions reported for athletes returning to sport after acute LAS. Evidence Acquisition: Data Sources: Databases PubMed, Embase, CINAHL, SPORTDiscus, and PEDro were searched to July 2020. Study Selection: A scoping review protocol was developed and followed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Extension for Scoping Reviews guidelines and registered (https://osf.io/bgek3/). Study selection included published articles on rehabilitation for ankle sprain in an athletic population. Data Extraction: Parameters included athlete and sport type, age, sex, intervention investigated, outcome measures, measurement tool, and follow-up period. Data Synthesis: A qualitative synthesis for all articles was undertaken, and a quantitative subanalysis of randomized controlled trials and critical methodological appraisal was also conducted. Evidence Synthesis: A total of 37 articles were included in this review consisting of 5 systematic and 20 narrative reviews, 7 randomized controlled trials, a single-case series, case report, position statement, critically appraised topic, and descriptive study. Randomized controlled trial interventions included early dynamic training, electrotherapy, and hydrotherapy. Conclusions: Early dynamic training after acute LAS in athletes results in a shorter time to return to sport, increased functional performance, and decreased self-reported reinjury. The results of this scoping review support an early functional and dynamic rehabilitation approach when compared to passive interventions for athletes returning to sport after LAS. Despite existing research on rehabilitation of LAS in the general population, a lack of evidence exists related to athletes seeking to return to sport.
Stephanie Wise and Jordan Bettleyon
Clinical Scenario: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy of the upper-extremity. Due to the involvement of the median nerve, long-term compression of this nerve can lead to hand dysfunction and disability that can impact work and daily life. As such, early treatment is warranted to prevent any long-term damage to the median nerve. Conservative management is utilized in those with mild to moderate CTS. Neural mobilizations can aid in the reduction of neural edema, neural mobility, and neural adhesion while improving nerve conduction. Clinical Question: Is neurodynamics effective in reducing pain and reported symptoms in those with CTS? Summary of Key Findings: Four studies were included, with 2 studies utilizing passive neural mobilizations, one study using active techniques, and one study using active neural mobilizations with splinting. All studies showed large effect size for pain, symptom severity, and physical function. Clinical Bottom Line: Neurodynamics is an effective treatment for CTS. Splinting is only effective when combined with neurodynamics. Strength of Recommendation: Level B evidence to support the use of neurodynamics for the treatment of CTS.
Masahiro Kuniki, Yoshitaka Iwamoto, Daiki Yamagiwa, and Nobuhiro Kito
Context: Core stability is important for preventing injury and improving performance. Although various tests for evaluating core stability have been reported to date, information on their relationship and the effect of gender differences is limited. This study aimed to (1) identify correlations among the 3 core stability tests and to examine the validity of each test and (2) identify gender differences in the test relationship and determine whether gender influenced test selection. Design: Cross-sectional study. Methods: Fifty-one healthy volunteers (27 men and 24 women) participated in the study. The participants underwent the following 3 tests: Sahrmann Core Stability Test (SCST), the lumbar spine motor control tests battery (MCBT), and Y Balance Test (YBT). Each parameter was analyzed according to all parameters and gender using the Spearman rank correlation coefficient. Results: Overall, there was a strong positive correlation between SCST and MCBT and moderate positive correlations between SCST and YBT and between MCBT and YBT. Conversely, gender-specific analyses revealed no significant correlations between YBT and SCST and between YBT and MCBT in women, although significantly strong correlations were found among all tests in men. Conclusion: Although these 3 tests evaluated interrelated functions and may be valid as core stability tests, the results should be carefully interpreted when performing YBT in women.
Seong-won Han, Andrew Sawatsky, and Walter Herzog
The purpose of this study was to quantify the contribution of the individual quadriceps muscles to patellar tracking. The individual and/or combined quadriceps muscles were activated in rabbits (n = 6) during computer-controlled flexion/extension of the knee. Three-dimensional patellar tracking was measured for the vastus lateralis, vastus medialis, and rectus femoris when activated alone and when activated simultaneously at different frequencies, producing a range of knee extensor torques. Patellar tracking changed substantially as a function of knee extensor torque and differed between muscles. Specifically, when all quadriceps muscles were activated simultaneously, the patella shifted more medially and proximally and rotated and tilted more medially compared with when vastus lateralis and rectus femoris were activated alone (P < .05), whereas vastus medialis activation alone produced a similar tracking pattern to that observed when all quadriceps muscles were activated simultaneously. Furthermore, patellar tracking for a given muscle condition shifted more medially and proximally and rotated and tilted more medially with increasing knee extensor torques across the entire range of knee joint angles. The authors conclude that patellar tracking depends crucially on knee extensor force/torque and that vastus medialis affects patellar tracking in a distinctly different way than vastus lateralis and rectus femoris, which produce similar tracking patterns.
Mojtaba Jahanshahi, Mohammad Hossein Nasermelli, Robert L. Baker, Pouya Rabiei, Maarten Moen, and Michael Fredericson
Context: Iliotibial band syndrome (ITBS) is a common overuse injury in runners with parallels to our findings of overuse in Greco Roman wrestlers. Despite research indicating coordination and movement-based factors about the hip, no studies were found using functional motor control (FMC) in runners or wrestlers with ITBS. Thus, we compared FMC exercises and therapeutic exercises (TEs) on pain, function, muscle strength, and range of motion (ROM) in national-level Greco Roman wrestlers with ITBS. Design: Controlled laboratory study. Methods: Sixty national-level Greco Roman wrestlers diagnosed with ITBS were randomly assigned to 8 weeks of FMC exercises, TE, and a control group (20 individuals for each group). Pain (visual analog scale), function (triple hop test for distance, single-leg vertical jump test, and agility T test), muscle strength (handheld dynamometer), and ROM (goniometer) were measured at baseline and 8 weeks after intervention as posttest. Results: Although both interventions significantly reduced pain (P < .001, η 2 = .87), improved function (triple hop test P = .004, η 2 = .94; single-leg vertical jump P = .002, η 2 = .93; and T test P < .001, η 2 = .93) and strength (hip abduction (P < .001, η 2 = .52), hip external rotation (P = .02, η 2 = .95), knee flexion (P ≤ .001, η 2 = .94), and knee extension (P < .001, η 2 = .91) compared with the control group, FMC showed more significant improvements in comparison with TE. Significant differences (P = .001) were observed between FMC and TE compared with the control group in ROM outcome. However, TE was more effective than FMC in improving ROM hip abduction (P < .001, η 2 = .93), hip adduction (P = .000, η 2 = .92), hip internal rotation (P < .001, η 2 = .92), and hip external rotation (P < .001, η 2 = .93). Conclusion: FMC exercises were superior to TE in terms of pain, function, and muscle strength, whereas TE was more effective for improving ROM. FMC exercise is suggested as an effective intervention for improvement of the outcomes related to ITBS in national-level Greco Roman wrestlers.
Abbis Jaffri, John J. Fraser, Rachel M. Koldenhoven, and Jay Hertel
Context: To investigate the effects of midfoot joint mobilization and a 1-week home exercise program, compared with a sham intervention, and home exercise program on pain, patient-reported outcomes, ankle–foot joint mobility, and neuromotor function in young adults with chronic ankle instability. Design: Crossover clinical trial. Methods: Twenty participants with chronic ankle instability were instructed in a stretching, strengthening, and balance home exercise program and were randomized a priori to receive either midfoot joint mobilizations (forefoot supination, cuboid glide, and plantar first tarsometatarsal) or a sham laying of hands on the initial visit. Changes in foot morphology, joint mobility, strength, dynamic balance, and patient-reported outcomes assessing pain, physical, and psychological function were assessed pre to post treatment and 1 week following post treatment. Participants crossed over to receive the alternate treatment and were assessed pre to post treatment and 1 week following. Linear modeling was used to assess changes in outcomes. Results: Participants demonstrated significantly greater perceived improvement immediately following midfoot mobilization in the single assessment numeric evaluation (sham: 5.0% [10.2%]; mobilization: 43.9% [26.2%]; β: 6.8; P < .001; adj R 2: .17; Hedge g: 2.09), and global rating of change (sham: −0.1 [1.1]; mobilization: 1.1 [3.0]; β: 1.8; P = .01; adj R 2: .12; Hedge g: 0.54), and greater improved 1-week outcomes in rearfoot inversion mobility (sham: 4.4° [8.4°]; mobilization: −1.6° [6.1°]; β: −6.37; P = .01; adj R 2: .19; Hedge g: 0.81), plantar flexion mobility (sham: 2.7° [6.4°]; mobilization: −1.7° [4.3°]; β: −4.36; P = .02; adj R 2: .07; Hedge g: 0.80), and posteromedial dynamic balance (sham: 2.4% [5.9%]; mobilization: 6.0% [5.4%]; β: 3.88; P = .04; adj R 2: .10; Hedge g: 0.59) compared to the sham intervention. Conclusion: Greater perceived improvement and physical signs were observed following midfoot joint mobilization.