Context: Impaired dorsiflexion range of motion (DFROM) has been established as a predictor of lower-extremity injury. Compression tissue flossing (CTF) may address tissue restrictions associated with impaired DFROM; however, a consensus is yet to support these effects. Objectives: To summarize the available literature regarding CTF on DFROM in physically active individuals. Evidence Acquisition: PubMed and EBSCOhost (CINAHL, MEDLINE, and SPORTDiscus) were searched from 1965 to July 2019 for related articles using combination terms related to CTF and DRFOM. Articles were included if they measured the immediate effects of CTF on DFROM. Methodological quality was assessed using the Physiotherapy Evidence Database scale. The level of evidence was assessed using the Strength of Recommendation Taxonomy. The magnitude of CTF effects from pre-CTF to post-CTF and compared with a control of range of motion activities only were examined using Hedges g effect sizes and 95% confidence intervals. Randomeffects meta-analysis was performed to synthesize DFROM changes. Evidence Synthesis: A total of 6 studies were included in the analysis. The average Physiotherapy Evidence Database score was 60% (range = 30%–80%) with 4 out of 6 studies considered high quality and 2 as low quality. Meta-analysis indicated no DFROM improvements for CTF compared with range of motion activities only (effect size = 0.124; 95% confidence interval, −0.137 to 0.384; P = .352) and moderate improvements from pre-CTF to post-CTF (effect size = 0.455; 95% confidence interval, 0.022 to 0.889; P = .040). Conclusions: There is grade B evidence to suggest CTF may have no effect on DFROM when compared with a control of range of motion activities only and results in moderate improvements from pre-CTF to post-CTF. This suggests that DFROM improvements were most likely due to exercises completed rather than the band application.
Devin S. Kielur and Cameron J. Powden
Kelly Cheever, Jeffrey T. Howard and Keisuke Kawata
Context: Increased injury rates following concussive injury have been attributed to decreased neuromuscular coordination frequently documented following a concussion. However, altered integration between the vestibular system and oculomotor pathways following impacts at subconcussive thresholds implicate all sports-related impacts not just those at a concussive threshold in future musculoskeletal injury. While, several studies have explored the utility of vestibular and oculomotor clinical testing to detect altered neuromuscular control and then correlated those alterations to future injury risk, no research has explored the use of cervical clinical tests in the same capacity. Outcome Measures: Cervical joint position error test, Neck Disability Index and head acceleration. Interventions: Soccer headers, fatigue protocol, soccer headers + fatigue. Objective: To explore the clinical utility of a novel clinical approach to measuring changes in cervical neuromuscular control following subconcussive impacts in a controlled lab environment. Participants: 40 current female colligate club soccer athletes were recruited. Inclusion criteria included between the age of 18 and 25 and a minimum of 4-year soccer heading experience. Setting: Laboratory. Design: A repeated-measures design with 4 groups was utilized to test the hypothesis. Results: A 65%, 54%, and 49% increased error was observed following the soccer heading, fatigue only, and soccer heading + fatigue interventions, respectively. Meanwhile, the controls saw a 6% decrease in neck position error. Concussion: While, cervical joint position error testing was sensitive to decreased neuromuscular coordination following soccer heading, it was not specific enough to rule out an exercise effect in the absence of subconcussive impacts. Further research is warranted to explore the clinical utility and specificity of cervical joint position error testing to measured alterations in supraspinal processing following subconcussive impacts, and how these alterations may lead to decreased coordination and movement of the body during sports-related task.
Figen Govsa, Gkionoul Nteli Chatzioglou, Simin Hepguler, Yelda Pinar and Ozden Bedre
Objective: This study examines the effect of the lower limb misalignment and its possible compensatory effect on plantar pressure in a normal population. The aim of this paper is to present a structured method for the analysis of posture and its changes using a standardized digital photography technique and plantar pressure measuring device. Design: Cohort. Setting: Laboratory. Participants: A total of 200 adult volunteers between 18 and 22 years of age who had no current symptoms of pain and foot or ankle pathology participated in the study. Main Outcome Measures: The gold standard measure of lower limb alignment with weight-bearing status is the mechanical axis and their angles using Image J software. Structural and functional measurements of the same foot were taken using a plantar pressure measuring device. In this study, 5 alignment (thigh, knee, leg, ankle, and foot) characteristics were measured on the lower limb using the 2 techniques, and, additionally, the foot contact area, peak pressure, foot axis, rearfoot angle, and subtalar joint flexibility score were analyzed in 10 different regions of the foot. Results: This study has shown a reasonable correlation between digitalized measurements and plantar pressures values. Quadriceps angle affected midfoot impulse, foot axis angle, subtalar joint minimum angle, and rearfoot angle positively. Subtalar joint flexibility scores were analyzed in 10 different regions of the foot. There was a positive correlation between rearfoot angle and quadriceps angle (P = .009, r = .261). Results of both methods show that they endorse each other. Conclusions: The posture of the standing feet may have influence on lower limb alignment. Currently, there are no studies carried out by using digital photogrammetry and foot scan. The authors claim that patient-friendly digital photogrammetry would have a positive contribution to the monitoring of patients, even including new ones in the treatment programs, reducing any possible loss in the personal and national economy.
Taylor K. Dinyer, Pasquale J. Succi, M. Travis Byrd, Caleb C. Voskuil, Evangeline P. Soucie and Haley C. Bergstrom
This study determined the load- and limb-dependent neuromuscular responses to fatiguing, bilateral, leg extension exercise performed at a moderate (50% one-repetition maximum [1RM]) and high load (80% 1RM). Twelve subjects completed 1RM testing for the bilateral leg extension, followed by repetitions to failure at 50% and 80% 1RM, on separate days. During all visits, the electromyographic (EMG) and mechanomyographic (MMG), amplitude (AMP) and mean power frequency (MPF) signals were recorded from the vastus lateralis of both limbs. There were no limb-dependent responses for any of the neuromuscular signals and no load-dependent responses for EMG AMP, MMG AMP, or MMG MPF (p = .301–.757), but there were main effects for time that indicated increases in EMG and MMG AMP and decreases in MMG MPF. There was a load-dependent decrease in EMG MPF over time (p = .032) that suggested variability in the mechanism responsible for metabolite accumulation at moderate versus high loads. These findings suggested that common drive from the central nervous system was used to modulate force during bilateral leg extension performed at moderate and high loads.
Liana M. Tennant, Erika Nelson-Wong, Joshua Kuest, Gabriel Lawrence, Kristen Levesque, David Owens, Jeremy Prisby, Sarah Spivey, Stephanie R. Albin, Kristen Jagger, Jeff M. Barrett, James D. Wong and Jack P. Callaghan
Spinal stiffness and mobility assessments vary between clinical and research settings, potentially hindering the understanding and treatment of low back pain. A total of 71 healthy participants were evaluated using 2 clinical assessments (posteroanterior spring and passive intervertebral motion) and 2 quantitative measures: lumped mechanical stiffness of the lumbar spine and local tissue stiffness (lumbar erector spinae and supraspinous ligament) measured via myotonometry. The authors hypothesized that clinical, mechanical, and local tissue measures would be correlated, that clinical tests would not alter mechanical stiffness, and that males would demonstrate greater lumbar stiffness than females. Clinical, lumped mechanical, and tissue stiffness were not correlated; however, gradings from the posteroanterior spring and passive intervertebral motion tests were positively correlated with each other. Clinical assessments had no effect on lumped mechanical stiffness. The males had greater lumped mechanical and lumbar erector spinae stiffness compared with the females. The lack of correlation between clinical, tissue, and lumped mechanical measures of spinal stiffness indicates that the use of the term “stiffness” by clinicians may require reevaluation; clinicians should be confident that they are not altering mechanical stiffness of the spine through segmental mobility assessments; and greater resting lumbar erector stiffness in males suggests that sex should be considered in the assessment and treatment of the low back.
Reza Heydari Armaki, Keramatollah Abbasnia and Alireza Motealleh
Objective: Patellofemoral pain (PFP) is the most commonly reported musculoskeletal overuse injury in active individuals, such as athletes, and is a multifactorial problem with no definite cause identified to date. Some studies have shown a relationship between impaired core and trunk sensorimotor control and knee disorders, especially PFP. The aim of this study was to evaluate trunk flexion proprioception by comparing the repositioning error between healthy athletes and athletes with PFP. Design: Cross-sectional case–control study. Setting: Rehabilitation sciences research center. Participants: Twenty healthy athletes and 20 athletes with PFP. Main Outcome Measures: To examine proprioception of trunk flexors, the absolute active and passive repositioning error at 30° and 60° trunk flexion were evaluated with isokinetic dynamometry. The results were compared between the two groups. Results: In the PFP group, the active trunk repositioning error at 30° flexion was significantly greater than in the healthy individuals (P < .001). The mean absolute active repositioning error at 30° flexion was 3.04° (1.37°) in the PFP group and 1.50° (0.70°) in the control group. There was no significant difference between groups in the active trunk repositioning error at 60° flexion (P = .066). The mean absolute active repositioning error at 60° flexion was 2.96° (1.26°) in the PFP group and 2.18° (0.99°) in the control group. The passive trunk repositioning error at 30° and 60° flexion was significantly greater in the PFP group (P = .013 and P = .004, respectively). The mean absolute passive repositioning error at 30° and 60° flexion in the PFP group was 2.94° (0.80°) and 3.13° (1.19°), respectively, and was 2.08° (1.08°) and 1.96° (0.71°), respectively, in the control group. The calculated eta-squared value showed that joint repositioning errors had large effect sizes (0.15–0.32). Conclusion: Trunk proprioception in the flexion direction may be impaired in patients with PFP. This finding suggests that trunk proprioception training may be important in rehabilitation for athletes with PFP.
Robert J. Reyburn and Cameron J. Powden
Context: Ankle braces have been theorized to augment dynamic balance. Objectives: To complete a systematic review with meta-analysis of the available literature assessing the effect of ankle braces on dynamic balance in individuals with and without chronic ankle instability (CAI). Evidence Acquisition: Electronic databases (PubMed, MEDLINE, CINAHL, and SPORTDiscus) were searched from inception to October 2019 using combinations of keywords related to dynamic balance, ankle braces, Star Excursion Balance Test (SEBT), Y-Balance Test (YBT), and Time to Stabilization. Inclusion criteria required that studies examined the effects of ankle braces on dynamic balance. Studies were excluded if they evaluated other conditions besides CAI, did not access dynamic balance, or did not use an ankle brace. Methodological quality was assessed using the Physiotherapy Evidence Database scale. The level of evidence was assessed using the Strength of Recommendation Taxonomy. The magnitude of brace effects on dynamic balance was examined using Hedges g effect sizes (ESs) and 95% confidence intervals (CIs). Random-effects meta-analysis was performed to synthesize SEBT/YBT and Time to Stabilization data separately. Data Synthesis: Seven studies were included with a median Physiotherapy Evidence Database score of 60% (range 50%–60%), and 4 were classified as high quality. Overall meta-analysis indicated a weak to no effect of braces on SEBT/YBT (ES = 0.117; 95% CI, −0.080 to 0.433; P = .177) and Time to Stabilization (ES = −0.064; 95% CI, −0.211 to 0.083, P = .083). Subanalysis of SEBT/YBT measures indicated a weak negative effect in healthy participants (ES = −0.116; 95% CI, −0.209 to −0.022, P = .015) and a strong positive effect in individuals with CAI (ES = 0.777; 95% CI, 0.418 to 1.136; P < .001). Conclusion: The current literature supports a strong effect of ankle braces on the SEBT/YBT in those with CAI. However, little to no dynamic balance changes were noted in healthy participants. Future research should include consistent ankle brace types, pathologic populations, and the examination of dynamic balance changes contribution to injury risk reduction.
Diulian Muniz Medeiros, César Marchiori and Bruno Manfredini Baroni
Context: Nordic hamstring exercise (NHE) has been widely employed to prevent hamstring strain injuries. However, it is still not clear which adaptations are responsible for the NHE preventive effects. Objectives: The aim of this study was to investigate the effects of NHE on knee flexors eccentric strength and fascicle length. Evidence Acquisition: The search strategy included MEDLINE, PEDro, and Cochrane CENTRAL from inception to April 2020. Randomized clinical trials that have analyzed the effects of NHE training on hamstring eccentric strength and/or fascicle length were included. Evidence Synthesis: From the 1932 studies identified, 12 were included in the systematic review, and 9 studies presented suitable data for the meta-analysis. All studies demonstrated strength increments in response to NHE training (10%–15% and 16%–26% in tests performed on the isokinetic dynamometer and on the NHE device, respectively), as well as significant enhancement of biceps femoris long head fascicle length (12%–22%). Meta-analysis showed NHE training was effective to increase knee flexors eccentric strength assessed with both isokinetic tests (0.68; 95% confidence interval, 0.29 to 1.06) and NHE tests (1.11; 95% confidence interval, 0.62 to 1.61). NHE training was also effective to increase fascicle length (0.97; 95% confidence interval, 0.46 to 1.48). Conclusions: NHE training has the potential of increasing both knee flexors eccentric strength and biceps femoris long head fascicle length.
Chee Vang and Alexander Niznik
Clinical Scenario: Patellar tendinopathy is a common musculoskeletal disorder affecting the lower-extremities and a difficult condition to manage for athletes that are in season. To facilitate improvement in function and to decrease pain, initial treatment for patellar tendinopathy is typically conservative. Traditional interventions may include eccentric training, cryotherapy, patellar counterforce straps, oral anti-inflammatories, injectable agents, phonophoresis, iontophoresis, orthotics, therapeutic ultrasound, and extracorporeal shockwave. In addition, recent literature suggests that implementing isometric and isotonic contractions may be effective in reducing patellar tendon pain. Focused Clinical Question: How effective are isometric contractions compared with isotonic contractions in reducing pain for in-season athletes with patellar tendinopathy? Summary of Key Findings: Implementation of isometric and isotonic exercises statistically reduced pain levels in the short term of 4 weeks for in-season athletes; however, isometric contractions provided statistically greater pain relief immediately for up to 45 minutes postintervention compared with isotonic contractions. Clinical Bottom Line: Current evidence supports the use of isometric and isotonic contractions to reduce pain for in-season athletes with patellar tendinopathy. Based on the reviewed literature, clinicians should consider utilizing heavy loaded isometrics or progressive heavy loaded isotonic exercises, which showed reduction in pain levels immediately after intervention and at 4-week follow-up for both intervention groups. Isometric contractions appear to provide greater pain relief immediately after intervention. Strength of Recommendation: There is Grade B evidence from 2 level 2 randomized controlled trials and 1 level 3 randomized crossover study supporting the use of isometric and isotonic contractions to reduce patellar tendon pain for in-season athletes.
Behnam Gholami-Borujeni, Ali Yalfani and Leila Ahmadnezhad
This study was conducted to evaluate the effects of 8-week inspiratory muscle training on activity in the ankle muscles of athletes with chronic low-back pain. A randomized controlled trial involving 45 men and women with chronic low-back pain was carried out. Electromyography activity in the tibialis anterior, peroneus longus, gastrocnemius medialis, and gastrocnemius lateralis muscles of the dominant leg was recorded. Secondary outcomes included biopsychosocial indices, such as pain, disability, anxiety and depression, fear-avoidance beliefs, and fear of (re)injury. Static and dynamic overhead squat tests showed that inspiratory muscle training decreased activity in the tibialis anterior, peroneus longus, and gastrocnemius medialis muscles. In the static single-leg squat test and the descending phase of the dynamic equivalent, such a decrease was observed in all the 4 muscles. Inspiratory muscle training significantly reduced pain severity and activity in the tibialis anterior, peroneus longus, and gastrocnemius medialis muscles during the ascending phase of the dynamic single-leg squat test. On the basis of the findings, 8 weeks of inspiratory muscle training may constitute useful rehabilitation for reducing excessive activity in ankle joint muscles and aiding chronic low-back pain recovery.