Brady M. Smith, David O. Draper, Robert D. Hyldahl and Justin H. Rigby
Context: Low current intensity iontophoresis treatments have increased skin perfusion over 700% from baseline potentially altering drug clearance from or diffusion to the targeted area. Objective: To determine the effects of a preceding 10-minute ice massage on subcutaneous dexamethasone sodium phosphate (Dex-P) concentration and skin perfusion during and after a 4-mA iontophoresis treatment. Design: Controlled laboratory study. Setting: Research laboratory. Patients or Other Participants: Twenty-four participants (male = 12, female = 12; age = 25.6 [4.5] y, height = 173.9 [8.51] cm, mass = 76.11 [16.84] kg). Intervention(s): Participants were randomly assigned into 2 groups: (1) pretreatment 10-minute ice massage and (2) no pretreatment ice massage. Treatment consisted of an 80-mA·minute (4 mA, 20 min) Dex-P iontophoresis treatment. Microdialysis probes (3 mm deep in the forearm) were used to assess Dex-P, dexamethasone (Dex), and its metabolite (Dex-Met) concentrations. Skin perfusion was measured using laser Doppler flowmetry. Main Outcome Measure(s): Microdialysis samples were collected at baseline, at conclusion of treatment, and every 20 minutes posttreatment for 60 minutes. Samples were analyzed to determine Dex-Total (Dex-Total = Dex-P + Dex + Dex-Met). Skin perfusion was calculated as a percentage change from baseline. A mixed-design analysis of variance was used to determine Dex-Total and skin perfusion difference between groups overtime. Results: There was no difference between groups (P = .476), but [Dex-Total] significantly increased over the course of the iontophoresis and posttreatment time (P < .001). Dex-P was measured in 18 of 24 participants with a mean concentration of 0.67 (1.09) μg/mL. Skin perfusion was significantly greater in the no ice treatment group (P = .002). Peak skin perfusion reached 27.74% (47.49%) and 117.39% (103.45%) from baseline for the ice and no ice groups, respectively. Conclusions: Ice massage prior to iontophoresis does not alter the tissue [Dex-Total] even with less skin perfusion.
Fábio Carlos Lucas de Oliveira, Amanda L. Ager and Jean-Sébastien Roy
Context: Recreational overhead athletes are exposed to high overload, which increases the risk of shoulder injuries. Reduction of the acromiohumeral distance (AHD) is often associated with rotator cuff–related shoulder pain (RCRSP) among the general population. However, the AHD of symptomatic shoulders of recreational athletes has not yet been compared with their asymptomatic shoulders. Objective: To compare the AHD of a symptomatic to asymptomatic shoulder at rest (0°) and 60° abduction. To establish the relationship between AHD, pain, and functional limitations of recreational athletes with RCRSP. Design: Cross-sectional study. Setting: University laboratory. Participants: A total of 45 recreational overhead athletes with RCRSP were examined. Main Outcome Measures: The AHD was measured by ultrasonography at 0° and 60° abduction (angles). Shoulder pain was assessed using a numeric pain scale, whereas functional limitations were assessed using the The Disabilities of the Arm, Shoulder, and Hand questionnaire. Differences in the between-shoulders condition (symptomatic and asymptomatic) were determined using 2-way analysis of variance for repeated measures. A Pearson correlation established the relationship between AHD, pain, and functional limitations. Results: No angles × shoulder condition interactions (P = .776) nor shoulder condition effects (P = .087) were detected, suggesting no significant differences (P > .05) between asymptomatic and symptomatic shoulders in the AHD at 0° or 60°. The AHD at 60° reduced significantly compared with 0° (3.05 [1.36] mm [2.77–3.33], angle effects: P < .001). The AHD at 0° and 60° was not correlated with pain or functional limitations (−.205 ≤ r ≤ .210, .167 ≤ P ≤ .585). Conclusions: The AHD of recreational athletes is not decreased in symptomatic shoulders compared with asymptomatic shoulders. Reduction of the AHD in symptomatic shoulders is not associated with an increase in pain or functional limitations of recreational athletes with RCRSP.
Svend Erik Mathiassen
Devin S. Kielur and Cameron J. Powden
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.
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.
Guneet Chawla, Madelon Hoppe, Nina Browner and Michael D. Lewek
The purpose of this study was to determine the difference in spatiotemporal gait measures induced by stepping to the beat of a metronome and to music cues of various frequencies in individuals with Parkinson’s disease. Twenty-one participants with Parkinson’s disease were instructed to time their steps to a metronome and music cues (at 85%, 100%, and 115% of overground cadence). The authors calculated cadence, cadence accuracy, and step length during each cue condition and an uncued control condition. The music and metronome cues produced comparable results in cadence manipulation, with reduced cadence accuracy noted at slower intended frequencies. Nevertheless, the induced cadence elicited a concomitant alteration in step length. The music and metronome cues produced comparable changes to gait, but suggest that temporal control is more limited at slower frequencies, presumably by the challenge of increasing the step length.
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.