Effects of transcutaneous electrical nerve stimulation on pain, function, and descending inhibition in people with non-specific chronic low-back pain: a study protocol for a randomized crossover trial.

BACKGROUND: Low back pain (LBP) is a significant public health problem, is very prevalent, and is often characterized by the persistence of symptoms. Transcutaneous electrical nerve stimulation (TENS) may benefit people with chronic LBP because it can activate descending inhibitory pathways and inhibit central excitability. However, previous studies that have investigated the effects of TENS on pain in people with LBP have failed to use proper intensities of current, and the timing of the assessment of pain was not performed during the peak of the analgesic response or functional activities. Therefore, the present study aims to assess the effects of TENS on measures of pain, function, and descending inhibition using the maximal tolerable intensity of TENS in participants with LBP. METHODS/DESIGN: This study will be a randomized crossover trial. The participants for this study will be recruited from various places, including the University of Hartford, physical therapy clinics, and local businesses in the Hartford area, as well as online websites geared towards clinical trial recruitment. A total of 34 participants will receive all three treatments: active TENS, placebo TENS, and no treatment control. The treatment order will be randomized using a website-based randomization tool. For active TENS, a modulating frequency of 2-125 Hz will be applied with a variable pulse duration and maximal tolerable intensity for 30 min. The TENS will be left on for post-treatment testing to assess the effects during its maximally effective period for a total of 50 to 60 min. Furthermore, the intensity may be turned down if muscle twitching is present to ensure blinding of the evaluator. For placebo TENS, the unit will deliver current for 45 s, ramping to 0 in the last 15 s. The primary outcome will be pain intensity at rest and with movement, determined using the numerical pain rating scale. The secondary outcomes will be pressure pain threshold, heat pain threshold, temporal summation of pain, conditioned pain modulation, sit-to-stand test, and repeated trunk flexion. The assessments will be performed immediately before and after treatment. Statistical analysis of the data obtained will consider a significance level of p < 0.05. DISCUSSION: This study will provide evidence concerning the effects and mechanisms of TENS treatment in participants with chronic non-specific low back pain. The outcomes, including pain, function, and descending inhibition, will help us gain a greater understanding of how TENS can be used for these participants. TRIAL REGISTRATION: ClinicalTrials.gov NCT05812885. Registered on 24th May 2023.

Does manual therapy meaningfully change quantitative sensory testing and patient reported outcome measures in patients with musculoskeletal impairments related to the spine?: A 'trustworthy' systematic review and meta-analysis.

OBJECTIVES: To perform a 'trustworthy' systematic review (SR) with meta-analysis on the potential mechanisms of manual therapy used to treat spinal impairments. DESIGN: SR with meta-analysis. LITERATURE SEARCH: Articles published between January 2010 and October 2022 from CENTRAL, CINAHL, MEDLINE, PubMed, ProQuest, and PEDro. METHODS: This SR included English-language randomized clinical trials (RCTs) involving manual therapy to treat spinal impairments in adults. The primary outcome was pressure pain thresholds (PPTs). To synthesize RCTs with high confidence in estimated effects using the GRADE, RCTs with questionable prospective, external, and internal validity, and high risk of bias (RoB) were excluded. RESULTS: Following title and abstract screening, 89 full-text RCTs were reviewed. Twenty-two studies included the criteria of interest. Sixteen were not prospectively registered, two contained discussion/conclusions judged to be inconsistent with the registry, and one was rated as having a high RoB. Three studies met the inclusion criteria; heterogeneous interventions and locations for PPT testing prevented synthesis into practice recommendations. The two studies with high confidence in estimated effects had small effect sizes, and one study had confidence intervals that crossed zero for the outcome measures of interest. DISCUSSION: Standardized PPT testing, as a potential measure of centrally mediated pain, could provide clues regarding the mechanisms of manual therapy or help identify/refine research questions. CONCLUSION: High-quality RCTs could not be synthesized into strong conclusions secondary to the dissimilarity in research designs. Future research regarding quantitative sensory testing should develop RCTs with high confidence in estimated effects that can be translated into strong recommendations.

Heart rate variability in adults with chronic musculoskeletal pain: A systematic review.

PURPOSE: The aim of this review was to compare the heart rate variability (HRV) responses at rest of adults with chronic musculoskeletal pain against healthy controls. METHODS: The PubMed, Scopus, Web of Science (Science and Social Science Citation Index), and CINAHL databases were searched, with no date restrictions. Two independent reviewers selected observational studies that characterized the HRV responses at rest in adults with chronic musculoskeletal pain compared with those of healthy controls. Methodological quality was assessed using the Downs and Black checklist. RESULTS: This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. HRV in adults with chronic musculoskeletal pain was evaluated systematically. Of the 4893 studies screened, 20 of poor-to-moderate quality met the inclusion criteria. Most studies used electrocardiography and at least one time and/or frequency domain index. Studies were found that investigated HRV in adults with temporomandibular disorders, neck pain, whiplash, low back pain, and fibromyalgia. The heterogeneity of the studies in relation to painful conditions, parameters or position for HRV analysis precluded a meta-analysis. In general, these studies seem to show increased sympathetic and decreased parasympathetic modulation in adults with musculoskeletal pain when compared to controls. CONCLUSIONS: Adults with musculoskeletal pain exhibited a decline in HRV compared to controls. However, definitive conclusions cannot be drawn since the evidence is heterogeneous and of moderate quality. Further high-quality research with standardized measurements is needed.

Effectiveness of interferential current in patients with chronic non-specific low back pain: a systematic review with meta-analysis.

BACKGROUND: There is no systematic review assessing the effectiveness of interferential current (IC) in patients with low back pain. OBJECTIVE: To investigate the effectiveness of IC in patients with chronic non-specific low back pain. METHODS: The databases PUBMED, EMBASE, PEDro, Cochrane Library, CINAHL, and SCIELO were searched. Randomized controlled trials reporting pain intensity and disability in patients with chronic non-specific low back pain, in which IC was applied were included. Methodological quality was assessed using the PEDro scale. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) was used to evaluate the quality of evidence. RESULTS: Thirteen RCTs were considered eligible for this systematic review (pooled n = 1367). Main results showed moderate-quality evidence and moderate effect sizes that IC probably reduces pain intensity and disability compared to placebo immediately post-treatment (Pain: MD = -1.57 points; 95% CI -2.17, -0.98; Disability: MD = -1.51 points; 95% CI -2.57, -0.46), but not at intermediate-term follow-up. Low-quality evidence with small effect size showed that IC may reduce pain intensity (SMD = -0.32; 95% CI -0.61, -0.03, p = 0.03) compared to TENS immediately post-treatment, but not for disability. There is very low-quality evidence that IC combined with other interventions (massage or exercises) may not further reduce pain intensity and disability compared to the other interventions provided in isolation immediately post-treatment. CONCLUSION: Moderate-quality evidence shows that IC is probably better than placebo for reducing pain intensity and disability immediately post-treatment in patients with chronic non-specific low back pain.

Features and methods to discriminate between mechanism-based categories of pain experienced in the musculoskeletal system: a Delphi expert consensus study.

ABSTRACT: Classification of musculoskeletal pain based on underlying pain mechanisms (nociceptive, neuropathic, and nociplastic pain) is challenging. In the absence of a gold standard, verification of features that could aid in discrimination between these mechanisms in clinical practice and research depends on expert consensus. This Delphi expert consensus study aimed to: (1) identify features and assessment findings that are unique to a pain mechanism category or shared between no more than 2 categories and (2) develop a ranked list of candidate features that could potentially discriminate between pain mechanisms. A group of international experts were recruited based on their expertise in the field of pain. The Delphi process involved 2 rounds: round 1 assessed expert opinion on features that are unique to a pain mechanism category or shared between 2 (based on a 40% agreement threshold); and round 2 reviewed features that failed to reach consensus, evaluated additional features, and considered wording changes. Forty-nine international experts representing a wide range of disciplines participated. Consensus was reached for 196 of 292 features presented to the panel (clinical examination-134 features, quantitative sensory testing-34, imaging and diagnostic testing-14, and pain-type questionnaires-14). From the 196 features, consensus was reached for 76 features as unique to nociceptive (17), neuropathic (37), or nociplastic (22) pain mechanisms and 120 features as shared between pairs of pain mechanism categories (78 for neuropathic and nociplastic pain). This consensus study generated a list of potential candidate features that are likely to aid in discrimination between types of musculoskeletal pain.

Effects of neuromuscular electrical stimulation on torque and performance in recreational distance runners: A randomized controlled trial.

INTRODUCTION: Neuromuscular electrical stimulation (NMES) is used by athletes to improve muscle performance. However, evidence on the use of NMES in long distance runners is scarce. As such, this study aimed to evaluate the effects of NMES on the muscle torque and sports performance of long-distance recreational runners. METHODS: This was a blinded randomized controlled trial. Data from 30 volunteers were analyzed. Participants were randomly allocated to an experimental (n = 15) or control group (n = 15). The experimental group was submitted to running training (RT) and a strengthening protocol with NMES (1 kHz, modulated in 2 ms bursts, 50 Hz modulated burst frequency and 10% duty cycle, 15 min totaling 18 contractions per sessions) for 6 weeks, with 3 sessions per week, while controls were submitted to RT alone. The following variables were analyzed: peak isometric (ISO), concentric (CON), and eccentric (ECC) torque of the quadriceps muscle in voluntary contractions, ventilatory anaerobic thresholds (VATs), maximal oxygen uptake (VO2max), and oxygen cost of transport (OCT). RESULTS: The NMES group obtained higher values of ISO, 21.04% (p = 0.001), CON, 21.97% (p = 0.001) and ECC, 18.74% (p = 0.001) peak torque and VAT1, 9.56% (p = 0.001), as well as a statistically significant improvement in oxygen cost of transport at VAT1 when compared to controls (p = 0.001). CONCLUSION: NMES was effective in improving peak isometric, concentric and eccentric quadriceps muscle torque, in addition to being an interesting resource for enhancing sports performance in long-distance recreational runners and future clinical trials should be performed to compare the use of NMES to different forms of training over longer training periods.

Biopsychosocial Aspects in Individuals with Acute and Chronic Rotator Cuff Related Shoulder Pain: Classification Based on a Decision Tree Analysis.

Biopsychosocial aspects seem to influence the clinical condition of rotator cuff related shoulder pain (RCRSP). However, traditional bivariate and linear analyses may not be sufficiently robust to capture the complex relationships among these aspects. This study determined which biopsychosocial aspects would better classify individuals with acute and chronic RCRSP and described how these aspects interact to create biopsychosocial phenotypes in individuals with acute and chronic RCRSP. Individuals with acute (

Immediate Effects of the Combination of Interferential Therapy Parameters on Chronic Low Back Pain: A Randomized Controlled Trial.

OBJECTIVES: To compare the immediate analgesic effects of 2 kHz or 4 kHz interferential current (IFC) with different amplitude-modulated frequencies (AMFs) (2 Hz or 100 Hz) on chronic low back pain (CLBP). DESIGN: Three-arm double-blinded randomized controlled trial. SETTING: Primary care. PARTICIPANTS: 175 patients (19 to 60 years of age, 105 female) with CLBP. INTERVENTIONS: One session of IFC: Interferential group (GI): GI2 kHz/100 Hz, GI2 kHz/2 Hz, GI4  kHz/100 Hz, GI4 kHz/2 Hz, or placebo. MAIN OUTCOMES MEASURES: Pain intensity by numerical rating scale of pain (NRS), McGill Pain Questionnaire (MPQ), and algometry. RESULTS: There was a significant difference in NRS scores (P < 0.05) in the GI2 kHz/2 Hz, GI4 kHz/2 Hz, and GI4 kHz/100 Hz groups compared with those of the placebo group (PG), and a significant difference in MPQ scores in the GI4 kHz/2 Hz and GI4 kHz/100 Hz groups compared with those of the PG. In algometry, only the GI4 kHz/100 Hz group showed a significant difference (by 2 points in the lumbar region) compared with the PG. Of the carrier frequencies, an IFC of 4 kHz showed more effective results, although no significant difference was noted between the AMFs. CONCLUSION: An IFC with a carrier frequency of 4 kHz and an AMF of 100 Hz provide immediate analgesic effects in individuals with CLBP. CLINICAL TRIAL REGISTRATION NUMBER: RBR-59YGRB.

Does the use of interferential current prior to pilates exercises accelerate improvement of chronic nonspecific low back pain?

AIM: To evaluate whether active interferential current (AIC) before pilates exercises improves pain faster than placebo interferential current (PIC) in patients with chronic nonspecific low back pain (CNLBP). METHODS: A total of 142 patients with CNLBP were treated with AIC or PIC before pilates exercises. Pain intensity was measured daily before and after treatment by Pain Numerical Rating Scale. Statistical analysis was performed using survival analysis for Kaplan-Meier method. RESULTS: The AIC group presented 30% reduction of pain one session, 50% reduction of pain two sessions and 100% reduction of pain three sessions faster than the PIC group and these improvements were statistically significant (p < 0.05). CONCLUSION: The AIC before pilates exercises can reduce pain faster than PIC in patients with CNLBP.

Low-level laser therapy and interferential current in patients with knee osteoarthritis: a randomized controlled trial protocol.

The aim of this study is to investigate the effects of low-level laser therapy and interferential current (IFC) on pain intensity, central sensitization, muscle strength and functional capacity in patients with knee osteoarthritis. Participants will be patients aged between 50 and 80 years, with knee osteoarthritis, pain intensity ranging from 3 to 8 points (0-10 scale), Lequesne Algofunctional Index ranging from 5 to 15 points, and Kellgren & Lawrence grade ≥2. A total of 168 patients will be randomly allocated into four groups as follows: active IFC + laser sham (G1), IFC sham + active laser (G2), active IFC + laser (G3) and IFC + laser sham (G4). Evaluators will be blinded to group allocation. Primary outcomes will be pain at rest and during movement measured with the visual analog pain scale. Clinical Trials Registry (NCT02898025. Registered on 20 April 2016).

Effects of transcutaneous electrical nerve stimulation on pain intensity during application of carboxytherapy in patients with cellulite: A randomized placebo-controlled trial.

BACKGROUND: Carboxytherapy may generate local pain that is considered the main limiting factor in clinical practice. Transcutaneous electric nerve stimulation (TENS) is widely used in the control of acute pain; however, the effect of TENS on pain relief during carboxytherapy has not been studied to date. AIMS: To assess the effect of TENS on pain intensity during carboxytherapy in patients with cellulite in the gluteal region. PATIENTS/METHODS: This randomized clinical trial was conducted with 84 patients, 18-44 years of age, who had moderate cellulite in the gluteal region, according to Cellulite Severity Scale, but never received carboxytherapy. Patients were randomized into 3 groups: active TENS, placebo TENS, and control group. For the intervention, skin depressions with cellulite were outlined, and the gluteal area to be treated was defined. The subcutaneous injection of CO2 was performed using 0.30 × 13 mm-needles at a 45° angle, with a controlled flow rate of 100 mL/min maintained for 1 minute at each puncture site. The parameters for TENS were as follows: frequency of 100 Hz and pulse duration of 200 µs; TENS intensity was adjusted until the patient reported strong paresthesia. The visual numeric pain rating scale was used to assess pain intensity after each puncture. RESULTS: The active TENS group reported lower pain intensity compared to the placebo TENS (P < .0001) and control (P < .0001) groups. CONCLUSIONS: Transcutaneous electric nerve stimulation (TENS) was effective in reducing pain intensity during carboxytherapy in patients with cellulite in the gluteal region.

High voltage pulsed current in collagen realignment, synthesis, and angiogenesis after Achilles tendon partial rupture.

OBJECTIVE: To verify the efficacy of high voltage pulsed current in collagen realignment and synthesis and in angiogenesis after the partial rupturing of the Achilles tendon in rats. METHOD: Forty male Wistar rats were randomized into four groups of 10 animals each: sham, cathodic stimulation, anodic stimulation, and alternating stimulation. Their Achilles tendons were submitted to direct trauma by a free-falling metal bar. Then, the treatment was administered for six consecutive days after the injury. In the simulation group, the electrodes were positioned on the animal, but the device remained off for 30 minutes. The other groups used a frequency of 120 pps, sensory threshold, and the corresponding polarity. On the seventh day, the tendons were removed and sent for histological slide preparation for birefringence and Picrosirius Red analysis and for blood vessel quantification. RESULTS: No significant difference was observed among the groups regarding collagen realignment (types I or III collagen) or quantity of blood vessels. CONCLUSION: High voltage pulsed current for six consecutive days was not effective in collagen realignment, synthesis, or angiogenesis after the partial rupturing of the Achilles tendon in rats.

High voltage pulsed current in collagen realignment, synthesis, and angiogenesis after Achilles tendon partial rupture

ABSTRACT Objective To verify the efficacy of high voltage pulsed current in collagen realignment and synthesis and in angiogenesis after the partial rupturing of the Achilles tendon in rats. Method Forty male Wistar rats were randomized into four groups of 10 animals each: sham, cathodic stimulation, anodic stimulation, and alternating stimulation. Their Achilles tendons were submitted to direct trauma by a free-falling metal bar. Then, the treatment was administered for six consecutive days after the injury. In the simulation group, the electrodes were positioned on the animal, but the device remained off for 30 minutes. The other groups used a frequency of 120 pps, sensory threshold, and the corresponding polarity. On the seventh day, the tendons were removed and sent for histological slide preparation for birefringence and Picrosirius Red analysis and for blood vessel quantification. Results No significant difference was observed among the groups regarding collagen realignment (types I or III collagen) or quantity of blood vessels. Conclusion High voltage pulsed current for six consecutive days was not effective in collagen realignment, synthesis, or angiogenesis after the partial rupturing of the Achilles tendon in rats.

Effect of High- and Low-Frequency Transcutaneous Electrical Nerve Stimulation on Angiogenesis and Myofibroblast Proliferation in Acute Excisional Wounds in Rat Skin.

OBJECTIVE: This study evaluated the effects of high- (HF) and low-frequency (LF) transcutaneous electrical nerve stimulation on angiogenesis and myofibroblast proliferation in acute excisional wounds in rat skin. DESIGN: This was an experimental controlled and randomized study. PARTICIPANTS: An excisional wound was made on the back of 90 adult male EPM1-Wistar rats using an 8-mm punch. INTERVENTIONS: The animals were randomly assigned to the HF group (80 Hz), LF group (5 Hz), or control group. Transcutaneous electrical nerve stimulation (pulse duration, 200 microseconds; current amplitude, 15 mA) was delivered (session length, 60 minutes) on 3 consecutive days. MEAN OUTCOME MEASURE: Immunohistochemistry was performed on postoperative days 3, 7, and 14 for counting blood vessels and myofibroblasts. MEAN OUTCOME RESULTS: The LF group had significantly more blood vessels than the HF group on day 3 (P = .004). The HF group had significantly less blood vessels than did the control group on days 7 (P = .002) and 14 (P = .034) and less myofibroblasts than did both the LF and control groups on day 3 (P = .004) and less than did the control group on day 7 (P = .001). CONCLUSION: There seems to be a benefit to the use of LF transcutaneous electrical nerve stimulation in the healing of acute excisional wounds, but further studies are warranted.

Can transcutaneous electrical nerve stimulation improve achilles tendon healing in rats?

BACKGROUND: Tendon injury is one of the most frequent injuries in sports activities. TENS is a physical agent used in the treatment of pain but its influence on the tendon's healing process is unclear. OBJECTIVE: To evaluate the influence of TENS on the healing of partial rupture of the Achilles tendon in rats. METHOD: Sixty Wistar rats were submitted to a partial rupture of the Achilles tendon by direct trauma and randomized into six groups (TENS or Sham stimulation) and the time of evaluation (7, 14, and 21 days post-injury). Burst TENS was applied for 30 minutes, 6 days, 100 Hz frequency, 2 Hz burst frequency, 200 µs pulse duration, and 300 ms pulse train duration. Microscopic analyses were performed to quantify the blood vessels and mast cells, birefringence to quantify collagen fiber alignment, and immunohistochemistry to quantify types I and III collagen fibers. RESULTS: A significant interaction was observed for collagen type I (p=0.020) where the TENS group presented lower percentage in 14 days after the lesion (p=0.33). The main group effect showed that the TENS group presented worse collagen fiber alignment (p=0.001) and lower percentage of collagen III (p=0.001) and the main time effect (p=0.001) showed decreased percentage of collagen III at 7 days (p=0.001) and 14 days (p=0.001) after lesion when compared to 21 days. CONCLUSIONS: Burst TENS inhibited collagen I and III production and impaired its alignment during healing of partial rupture of the Achilles tendon in rats.

Can transcutaneous electrical nerve stimulation improve achilles tendon healing in rats?

BACKGROUND: Tendon injury is one of the most frequent injuries in sports activities. TENS is a physical agent used in the treatment of pain but its influence on the tendon's healing process is unclear. OBJECTIVE: To evaluate the influence of TENS on the healing of partial rupture of the Achilles tendon in rats. METHOD: Sixty Wistar rats were submitted to a partial rupture of the Achilles tendon by direct trauma and randomized into six groups (TENS or Sham stimulation) and the time of evaluation (7, 14, and 21 days post-injury). Burst TENS was applied for 30 minutes, 6 days, 100 Hz frequency, 2 Hz burst frequency, 200 µs pulse duration, and 300 ms pulse train duration. Microscopic analyses were performed to quantify the blood vessels and mast cells, birefringence to quantify collagen fiber alignment, and immunohistochemistry to quantify types I and III collagen fibers. RESULTS: A significant interaction was observed for collagen type I (p=0.020) where the TENS group presented lower percentage in 14 days after the lesion (p=0.33). The main group effect showed that the TENS group presented worse collagen fiber alignment (p=0.001) and lower percentage of collagen III (p=0.001) and the main time effect (p=0.001) showed decreased percentage of collagen III at 7 days (p=0.001) and 14 days (p=0.001) after lesion when compared to 21 days. CONCLUSIONS: Burst TENS inhibited collagen I and III production and impaired its alignment during healing of partial rupture of the Achilles tendon in rats.

Inhibitory effects of low-level laser therapy on skin-flap survival in a rat model.

BACKGROUND: Although several studies have demonstrated the effects of low-level laser therapy (LLLT) on skin flap viability, the role of higher doses has been poorly investigated. OBJECTIVE: To investigate the inhibitory effect of the LLLT (λ=670 nm) on the viability of random skin flaps in a rat model using an irradiation energy of 2.79 J at each point. METHODS: Sixteen Wistar rats were randomly assigned into two groups: sham laser irradiation (n=8); and active laser irradiation (n=8). Animals in the active laser irradiation group were irradiated with a 670 nm diode laser with an energy of 2.79 J/point, a power output 30 mW, a beam area of 0.028 cm(2), an energy density of 100 J/cm(2), an irradiance of 1.07 W/cm(2) for 93 s/point. Irradiation was performed in 12 points in the cranial skin flap portion. The total energy irradiated on the tissue was 33.48 J. The necrotic area was evaluated on postoperative day 7. RESULTS: The sham laser irradiation group presented a mean (± SD) necrotic area of 47.96±3.81%, whereas the active laser irradiation group presented 62.24±7.28%. There was a significant difference in skin-flap necrosis areas between groups (P=0.0002). CONCLUSION: LLLT (λ=670 nm) increased the necrotic area of random skin flaps in rats when irradiated with an energy of 2.79 J (100 J/cm(2)).

HISTORIQUE: Plusieurs études ont démontré les effets de la thérapie laser de faible intensité (TLFI) sur la viabilité des lambeaux cutanés, mais le rôle de plus fortes doses a été peu évalué. OBJECTIF: Examiner l'effet inhibiteur de la TLFI (λ=670 nm) sur la viabilité de lambeaux cutanés aléatoires d'un modèle murin au moyen d'une énergie d'irradiation de 2,79 J à chaque point. MÉTHODOLOGIE: Les chercheurs ont réparti 16 rats Wistar en deux groupes aléatoires : irradiation laser factice (n=8) et irradiation laser active (n=8). Les animaux du groupe d'irradiation laser active ont été irradiés à l'aide d'une diode laser de 670 nm à une énergie de 2,79 J/point, une puissance de 30 mW, un faisceau de 0,028 cm2, une densité énergétique de 100 J/cm2 et une radiation de 1,07 W/cm2 pendant 93 s/point. Douze points ont été irradiés sur la portion du lambeau cutané crânien. L'énergie totale irradiée sur les tissus s'élevait à 33,48 J. Les chercheurs ont évalué la zone nécrosée le septième jour après l'opération. RÉSULTATS: Le groupe d'irradiation laser factice présentait une zone nécrosée moyenne de (± ÉT) 47,96±3,81 %, tandis que le groupe d'irradiation laser active présentait une zone de 62,24±7,28 %. On constatait une différence importante entre les zones nécrosées des lambeaux cutanés des deux groupes (P=0,0002). CONCLUSION: La TLFI (λ=670 nm) accroissait la zone nécrosée des lambeaux cutanés murins aléatoires lorsqu'ils étaient irradiés par une énergie de 2,79 J (100 J/cm2).

Anthropometry of the breast region: how to measure?

BACKGROUND: Breast region measurements are important for research, but they may also become significant in the legal field as a quantitative tool for preoperative and postoperative evaluation. Direct anthropometric measurements can be taken in clinical practice. The aim of this study was to compare direct breast anthropometric measurements taken with a tape measure and a compass. METHODS: Forty women, aged 18-60 years, were evaluated. They had 14 anatomical landmarks marked on the breast region and arms. The union of these points formed eight linear segments and one angle for each side of the body. The volunteers were evaluated by direct anthropometry in a standardized way, using a tape measure and a compass. RESULTS: Differences were found between the tape measure and the compass measurements for all segments analyzed (p>0.05). CONCLUSION: Measurements obtained by tape measure and compass are not identical. Therefore, once the measurement tool is chosen, it should be used for the pre- and postoperative measurements in a standardized way. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Low-level laser therapy and light-emitting diode effects in the secretion of neuropeptides SP and CGRP in rat skin.

The phototherapy effects in the skin are related to biomodulation, usually to accelerate wound healing. However, there is no direct proof of the interrelation between the effects of low-level laser therapy (LLLT) and light-emitting diode (LED) in neuropeptide secretion, these substances being prematurely involved in the neurogenic inflammation phase of wound healing. This study therefore focused on investigating LLLT and LED in Calcitonin gene-related peptide (CGRP) and substance P (SP) secretion in healthy rat skin. Forty rats were randomly distributed into five groups with eight rats each: Control Group, Blue LED Group (470 nm, 350 mW power), Red LED Group (660 nm, 350 mW power), Red Laser Group (660 nm, 100 mW power), and Infrared Laser Group (808 nm, 100 mW power) (DMC® Equipamentos Ltda., São Carlos, São Paulo, Brazil). The skin of the animals in the experimental groups was irradiated using the punctual contact technique, with a total energy of 40 J, single dose, standardized at one point in the dorsal region. After 14 min of irradiation, the skin samples were collected for CGRP and SP quantification using western blot analysis. SP was released in Infrared Laser Group (p = 0.01); there was no difference in the CGRP secretion among groups. Infrared (808 nm) LLLT enhances neuropeptide SP secretion in healthy rat skin.

The influence of stimulus phase duration on discomfort and electrically induced torque of quadriceps femoris

BACKGROUND: Although a number of studies have compared the influence of different electrical pulse parameters on maximum electrically induced torque (MEIT) and discomfort, the role of phase duration has been poorly investigated. OBJECTIVE: To examine the variation in muscle torque and discomfort produced when electrically stimulating quadriceps femoris using pulsed current with three different phase durations in order to establish whether there are any advantages or disadvantages in varying the phase duration over the range examined. METHOD: This is a two repeated-measures, within-subject study conducted in a research laboratory. The study was divided into 2 parts with 19 healthy young adults in each part.In part 1, MEIT was determined for each phase duration (400, 700, and 1000 µs), using a biphasic pulsed current at a frequency of 50 Hz. In part 2, stimulus amplitude was increased until the contractions reached 40% of maximum voluntary isometric contraction (MVIC) and the associated discomfort produced by each phase duration was measured. RESULTS: In part 1 of the study, we found that the average MEITs generated with each phase duration (400, 700, and 1000 µs) were 55.0, 56.3, and 58.0% of MVIC respectively, but the differences were not statistically significant (p=.45). In part 2, we found a statistically significant increase in discomfort over the same range of phase durations. The results indicate that, for a given level of torque production, discomfort increases with increasing phase duration (p=.008). CONCLUSIONS: Greater muscle torque cannot be produced by increasing the stimulus phase duration over the range examined. Greater discomfort is produced by increasing the stimulus phase duration. .