Electrophysical Agents: Implications of their Availability and Use in Undergraduate Clinical Placements

Changes in availability and usage of electrophysical agents by physical therapists: a 5 year longitudinal follow-up study

[Purpose] There have been concerns that the availability and usage of electrophysical agents have decreased, based on data from cross-sectional surveys. The aim of this study was to conduct the first five-year follow-up longitudinal survey to determine the changes in the availability and usage of electrophysical agents in Nagano Prefecture, Japan. [Participants and Methods] This longitudinal observational study employed the same postal questionnaire survey of practicing clinicians in 2014 and 2019. A total of 22 modalities had been selected for inclusion in the questionnaire based on what is used in clinical facilities and hospitals. [Results] The response rate was 71% and 63% for 2014 and 2019, respectively. The modalities that were high in availability and usage for both 2014 and 2019 were hot packs, ultrasound, cryotherapy and low frequency. While most modalities demonstrated a decreased trend in usage, electrical stimulation devices increased from 2014 to 2019. The results also demonstrated that usage was affected by gender (males greater than females), years of experience (older greater than younger), qualifications (diplomas greater than degrees), and confidence (confident greater than non-confident). [Conclusion] Our results may assist educators with designing educational curricula that is consistent with the needs of clinicians.

Objective structured clinical examination (OSCE) to assess the clinical skills of physical therapy students when using physical agents

Introduction: The use of physical agents in physical therapy (PT) requires clinical reasoning, as well as knowledge of their risks and contraindications; however, deficiencies may be observed when used in clinical practice. Objective: To implement the Objective Structured Clinical Evaluation (OSCE) method for the assessment of clinical skills among physical therapy specialty students when using physical agents. Materials and methods: A pilot, non-experimental, cross-sectional study was conducted in 114 physical therapy students enrolled during the first semester of 2019 in a physical agents course offered at the Universidad Andres Bello, Santiago, Chile. The OSCE consisted of 7 peer-validated stations, in which various skills were implemented in simulated clinical scenarios to achieve learning outcomes associated with the use of physical agents, namely: S1: connective tissue flexibility; S2: muscle relaxation; S3: analgesia; S4: drainage; S5: muscle strengthening; S6: parameter interpretation; and S7: equipment installation. Observers at each station assessed students’ clinical skills and decision-making using a checklist. OSCE scores were described using medians and interquartile ranges, representing the data dispersion between the 25th and 75th percentile (P25-P75). Station scores by sex were compared using the Mann-Whitney U test. Results: Median scores were higher than the minimum passing score in stations S1 (66, IQR: 52-70), S2 (55, IQR: 45-60), S3 (60, IQR: 50-69), S4 (65, IQR: 55-73), and S7 (40, IQR: 33-45), but they were below the passing score in stations S5 (54, IQR:46-65) and S6 (10, IQR: 9-13). In addition, 101 (88.59%) students had a global passing score in the OSCE. Conclusion: The OSCE scores obtained by the participants show their attainment of clinical skills when using physical agents since most of them obtained a global passing score; however, reinforcing the clinical skills for parameter interpretation is necessary, considering that the lowest mean score was obtained in said station.

Electrophysical agents in clinical practice of orthopedic and sports physical therapists in Brazil

ABSTRACT Studies have described the use of electrophysical agents (EPA) by physical therapists worldwide. However, the use of EPA by Brazilian physical therapists remains undetermined. This study aims to describe the availability, use, and perception about EPA by orthopedic and sports physical therapists in Brazil. Professionals of the area were invited to answer an online questionnaire. Demographic data and information regarding the availability, use and perception about EPA in their current clinical practice were asked. Out of 376 physical therapists included in this study, 89% declared to use EPA in clinical practice. Sensory electrotherapy with pulsed current (TENS), therapeutic ultrasound, excitomotor electrotherapy with pulsed current (FES/NMES), and cryotherapy are available for more than 3/4 of interviewees. Scientific articles and clinical experience, respectively, are the most influential factors for the choice of EPA. Ultrasound is the most frequently used EPA, followed by TENS, cryotherapy, photobiomodulation, hot packs, and FES/NMES. The top-five most useful EPA in clinical practice chosen by physical therapists are: (1) ultrasound; (2) photobiomodulation; (3) TENS; (4) cryotherapy; and (5) FES/NMES. In conclusion, EPA are widely used by orthopedic and sports physical therapists in Brazil. Therapeutic ultrasound, TENS, FES/NMES, photobiomodulation, cryotherapy, and hot packs are the most used EPA in clinical practice of these physiotherapists.

Study protocol of hypoalgesic effects of low frequency and burst-modulated alternating currents on healthy individuals

The aim of the study will be to compare different types of analgesic electrical currents in relation to the pressure pain threshold and sensory comfort in healthy individuals. A total of 100 individuals will be randomly assigned to four groups: transcutaneous electrical nerve stimulation, interferential current, Aussie current or placebo. The electrical stimulation will be administered with a strong level for 30 min and to the placebo group, the electrodes will be positioned while the equipment will remain switched off. The pressure pain threshold and sensory comfort will be measured with an algometer and the visual analogue scale, respectively. The level of significance will be p < 0.05. Study registration: NCT01950728 (clinical trials).

Availability, usage, and factors affecting usage of electrophysical agents by physical therapists: a regional cross-sectional survey

[Purpose] The aim of this study was to investigate the availability, usage, and factors affecting usage of electrophysical agents by physical therapists in Nagano Prefecture, Japan. [Subjects and Methods] Questionnaires were sent to all 1,571 physical therapists working in 245 institutions within Nagano Prefecture. A total of 1,110 questionnaires were returned, out of which 1,099 (70%) questionnaires containing valid responses were analyzed. Frequencies and percentages were calculated for 22 modalities with regards to availability, usage, rate of usage, and confidence level in usage. Factors affecting usage and the relationship between rate of usage and confidence level (Spearman’s rho) were also determined. [Results] The top three responses for the various outcome measures were as follows: (1) hot packs (88%), low frequency stimulators (76%), and ultrasound (68%) for availability; (2) hot packs (72%), ultrasound (61%), and cold packs (59%) for usage; (3) hot packs (75%), cold spray (49%), and ultrasound (44%) for confidence in usage; and (4) equipment availability (80%), past experience (79%), and research evidence (78%) for factors affecting usage. There was a significant positive relationship between confidence and usage for all modalities, except for ultraviolet radiation, iontophoresis, and magnetic field. [Conclusion] Usage was strongly correlated with confidence, with the top three used modalities also being the ones with the highest confidence in usage.

Sustained Acoustic Medicine: A Novel Long Duration Approach to Biomodulation Utilizing Low Intensity Therapeutic Ultrasound

Therapeutic ultrasound is an established technique for biomodulation used by physical therapists. Typically it is used to deliver energy locally for the purpose of altering tissue plasticity and increasing local circulation. Access to ultrasound therapy has been limited by equipment and logistic requirements, which has reduced the overall efficacy of the therapy. Ultrasound miniaturization allows for development of portable, wearable, self-applied ultrasound devices that sidestep these limitations. Additionally, research has shown that the timescale of acoustic stimulation matters, and directly affects the quality of result. This paper describes a novel, long duration approach to therapeutic ultrasound and reviews the current data available for a variety of musculoskeletal conditions.

Electrical stimulation for pain relief in knee osteoarthritis: systematic review and network meta-analysis

OBJECTIVE

To investigate the efficacy of different electrical stimulation (ES) therapies in pain relief of patients with knee osteoarthritis (OA).

METHOD

Electronic databases including MEDLINE, Embase and Cochrane Library were searched through for randomized controlled trials (RCTs) comparing any ES therapies with control interventions (sham or blank) or with each other. Bayesian network meta-analysis was used to combine both the direct and indirect evidence on treatment effectiveness.

RESULTS

27 trials and six kinds of ES therapies, including high-frequency transcutaneous electrical nerve stimulation (h-TENS), low-frequency transcutaneous electrical nerve stimulation (l-TENS), neuromuscular electrical stimulation (NMES), interferential current (IFC), pulsed electrical stimulation (PES), and noninvasive interactive neurostimulation (NIN), were included. IFC is the only significantly effective treatment in terms of both pain intensity and change pain score at last follow-up time point when compared with the control group. Meanwhile, IFC showed the greatest probability of being the best option among the six treatment methods in pain relief. These estimates barely changed in sensitivity analysis. However, the evidence of heterogeneity and the limitation in sample size of some studies could be a potential threat to the validity of results.

CONCLUSION

IFC seems to be the most promising pain relief treatment for the management of knee OA. However, evidence was limited due to the heterogeneity and small number of included trials. Although the recommendation level of the other ES therapies is either uncertain (h-TENS) or not appropriate (l-TENS, NMES, PES and NIN) for pain relief, it is likely that none of the interventions is dangerous.

LEVEL OF EVIDENCE

LevelⅡ, systematic review and network meta-analysis of RCTs.

The efficacy, safety, effectiveness, and cost-effectiveness of ultrasound and shock wave therapies for low back pain: a systematic review

BACKGROUND CONTEXT

Shock wave and especially ultrasound are commonly used to treat low back pain (LBP) in routine practice.

PURPOSE

To assess the evidence on the efficacy, effectiveness, cost-effectiveness, and safety of ultrasound and shock wave to treat LBP.

STUDY DESIGN

Systematic review.

METHODS

An electronic search was performed in MEDLINE, EMBASE, and the Cochrane Library databases up to July 2009 to identify randomized controlled trials (RCTs) comparing vibrotherapy with placebo or with other treatments for LBP. No language restrictions were applied. Additional data were requested from the authors of the original studies. The risk of bias of each study was assessed following the criteria recommended by the Cochrane Back Review Group.

RESULTS

Thirteen studies were identified. The four RCTs complying with the inclusion criteria included 252 patients. Two of the three RCTs on ultrasound had a high risk of bias. For acute patients with LBP and leg pain attributed to disc herniation, ultrasound, traction, and low-power laser obtained similar results. For chronic LBP patients without leg pain, ultrasound was less effective than spinal manipulation, whereas a shock wave device and transcutaneous electrical nerve stimulation led to similar results. Results from the only study comparing ultrasound versus a sham procedure are unreliable because of the inappropriateness of the sham procedure, low sample size, and lack of adjustment for potential confounders. No study assessed cost-effectiveness. No adverse events were reported.

CONCLUSION

The available evidence does not support the effectiveness of ultrasound or shock wave for treating LBP. High-quality RCTs are needed to assess their efficacy versus appropriate sham procedures, and their effectiveness and cost-effectiveness versus other procedures shown to be effective for LBP. In the absence of such evidence, the clinical use of these forms of treatment is not justified and should be discouraged.

Penetration and spread of interferential current in cutaneous, subcutaneous and muscle tissues

OBJECTIVES

To investigate the penetration depth of interferential current (IFC) through soft tissue and the area over which it spreads during clinical application.

DESIGN

A laboratory-based study of healthy participants.

SETTING

A university research laboratory.

PARTICIPANTS

Twelve healthy subjects.

INTERVENTIONS

Premodulated IFC at 90 Hz and 'true' IFC at frequencies of 4, 40 and 90 Hz were applied via four electrodes, in a quadrant setting, to the distal medial thigh of each participant on separate occasions.

MAIN OUTCOME MEASURE

Voltage induced by tested currents was measured at three locations (middle of the four electrodes, in line with one circuit and outside the four electrodes) and three depths (skin, subcutaneous and muscle tissues) using three Teflon-coated needle electrodes connected to a Cambridge Electronic Design data acquisition system.

RESULTS

All voltages were greater at all depths and locations compared with baseline (P<0.001): premodulated IFC [mean difference 0.112, 95% confidence interval (CI) 0.065 to 0.160], 4 Hz (mean difference 0.168, 95% CI 0.106 to 0.229), 40 Hz (mean difference 0.165, 95% CI 0.107 to 0.223) and 90 Hz (mean difference 0.162, 95% CI 0.102 to 0.221). Voltages decreased with depth. Lower voltages of all currents were recorded in the middle of the four electrodes, with the highest voltage for 'true' IFC being recorded outside the four electrodes (mean difference 0.04, 95% CI 0.01 to 0.029; P=0.011). The premodulated IFC had the highest voltage in line with one circuit.

CONCLUSIONS

IFC passed through soft tissues, with the highest voltages recorded in superficial tissue and the lowest voltages recorded in muscle. For 'true' IFC, the current spread outside the electrodes at higher voltages compared with the intersection of the four electrodes. The premodulated IFC had the highest voltage in line with one circuit. In terms of higher recorded voltages, 'true' IFCs were more efficient than the premodulated IFC when targeting deeper tissues. However, further studies with larger samples are required to confirm the results of this study.

Effectiveness of interferential current therapy in the management of musculoskeletal pain: a systematic review and meta-analysis

BACKGROUND

Interferential current (IFC) is a common electrotherapeutic modality used to treat pain. Although IFC is widely used, the available information regarding its clinical efficacy is debatable.

PURPOSE

The aim of this systematic review and meta-analysis was to analyze the available information regarding the efficacy of IFC in the management of musculoskeletal pain.

DATA SOURCES

Randomized controlled trials were obtained through a computerized search of bibliographic databases (ie, CINAHL, Cochrane Library, EMBASE, MEDLINE, PEDro, Scopus, and Web of Science) from 1950 to February 8, 2010.

DATA EXTRACTION

Two independent reviewers screened the abstracts found in the databases. Methodological quality was assessed using a compilation of items included in different scales related to rehabilitation research. The mean difference, with 95% confidence interval, was used to quantify the pooled effect. A chi-square test for heterogeneity was performed.

DATA SYNTHESIS

A total of 2,235 articles were found. Twenty studies fulfilled the inclusion criteria. Seven articles assessed the use of IFC on joint pain; 9 articles evaluated the use of IFC on muscle pain; 3 articles evaluated its use on soft tissue shoulder pain; and 1 article examined its use on postoperative pain. Three of the 20 studies were considered to be of high methodological quality, 14 studies were considered to be of moderate methodological quality, and 3 studies were considered to be of poor methodological quality. Fourteen studies were included in the meta-analysis.

CONCLUSION

Interferential current as a supplement to another intervention seems to be more effective for reducing pain than a control treatment at discharge and more effective than a placebo treatment at the 3-month follow-up. However, it is unknown whether the analgesic effect of IFC is superior to that of the concomitant interventions. Interferential current alone was not significantly better than placebo or other therapy at discharge or follow-up. Results must be considered with caution due to the low number of studies that used IFC alone. In addition, the heterogeneity across studies and methodological limitations prevent conclusive statements regarding analgesic efficacy.

Eccentric calf muscle training compared with therapeutic ultrasound for chronic Achilles tendon pain--a pilot study

A number of studies have indicated that eccentric calf muscle training has beneficial effects in the management of Achilles tendon pain for recreational athletes. The purpose of this prospective randomised single blind pilot study was to investigate their potential effectiveness compared with therapeutic ultrasound in subjects with relatively sedentary lifestyles in an NHS hospital setting. Eleven men and five women (mean age 53+/-21 years) with Achilles tendon pain of minimum duration 4 months were randomised to one of two treatment groups; either eccentric loading or ultrasound. Administration of ultrasound and regular supervision of exercises occurred over a period of 6 weeks, with unsupervised exercises continuing for another 6 weeks. Outcome measurements were taken prior to and after 2, 4, 6 and 12 weeks after commencing treatment. They included: pain on a visual analogue scale, functional index of the leg and lower limb, and the five question EuroQol generalised health questionnaire. The difference in mean score was calculated together with 95% confidence intervals assuming a normal distribution. There were no statistically significant differences between groups or clear trends over time. In addition there was considerable overlap between the confidence intervals. This is not unexpected given the small sample size. Both interventions proved acceptable to the patients with no adverse effects. On this basis we intend conducting a full multi-centred study.

Therapeutic ultrasound: the effects upon cutaneous blood flow in humans

The premise of the current crossover, randomised, double-blinded and controlled study was to ascertain the physiologic effects of pulsed and continuous ultrasound (US) upon cutaneous blood flow in humans as measured by laser Doppler flowmetry. Ten healthy volunteers (5 male, 5 female; aged 18 to 36 y) were assigned to undergo four experimental conditions in a predetermined random order: (i) control, (ii) placebo, (iii) pulsed US and (iv) continuous US. US was applied at a frequency of 3 MHz at an intensity of 1 W/cm(2) for a total of 6 min over the lateral aspect of the forearm. Ambient and skin temperatures were measured concomitantly. Statistical analysis indicated that there were significant differences in blood perfusion units between pulsed US and continuous application of US compared with the control condition for cutaneous blood flow at 2 min (p < or = 0.05), 4 min (p < or = 0.03) and 6 min (p < or = 0.05). Additionally, the placebo group was found only significantly to be different from the control condition at 6 min (p = 0.02), indicating that the movement of the transducer head can produce an additional massage effect. There were no significant differences found for ambient or skin temperature recordings. These findings suggest that active US produces significant increases in cutaneous blood flow.

Physical agents used in the management of chronic pain by physical therapists

Evidence supporting the use of specific physical agents in the management of chronic pain conditions is not definitive; it is largely incomplete and sometimes contradictory. However, the use of agents in chronic pain management programs is common. Within the broad use of physical agents, they are rarely the sole modality of treatment. A 1995 American Physical Therapy Association position statement asserts that "Without documentation which justifies the necessity of the exclusive use of physical agents/modalities, the use of physical agents/modalities, in the absence of other skilled therapeutic or educational intervention, should not be considered physical therapy". Physical agents may serve as useful adjunctive modalities of pain relief or to enhance the effectiveness of other elements in therapy geared toward resolution of movement impairments and restoration of physical function. Given that a conclusive aggregate of findings is unlikely to exist for all permutations of patient conditions, combined with interacting therapeutic modalities, an evidence-based approach to pain management is not always possible or beneficial to the patient. In the face of inconclusive evidence, a theory-based approach may help determine if the therapeutic effect ofa given physical agent has the possibility of being a useful clinical tool in the context of treating a particular patient's mechanism of pain generation. Until controlled efficacy findings are definitive, careful individual patient response monitoring of thoughtful theoretical application of adjunctive physical agents may be a prudent approach to the management of chronic pain.

The effect of heat on tissue extensibility: A comparison of deep and superficial heating

OBJECTIVE

To compare the effects of deep heating (shortwave diathermy [SWD]) and superficial heating (hydrocollator packs) on tissue extensibility.

DESIGN

A double-blind, repeated-measures study. Possible effects of sex and intervention order were controlled.

SETTING

A clinical laboratory.

PARTICIPANTS

Twenty-four subjects with no neurologic or musculoskeletal pathologies affecting their lower limbs.

INTERVENTIONS

Three intervention conditions: deep heating (SWD), superficial heating (hot packs), and no heating were applied in preallocated order to each subject at least 36 hours apart.

MAIN OUTCOME MEASURES

Ankle dorsiflexion in weight bearing was measured by using an inclinometer to ascertain changes in the extensibility of the calf muscles and associated soft tissues.

RESULTS

Deep heating increased the range of ankle dorsiflexion by 1.8 degrees +/-1.9 degrees . The change in ankle dorsiflexion after superficial and no heating was 0.7 degrees +/-1.5 degrees and -0.1 degrees +/-1.0 degrees , respectively.

CONCLUSIONS

Deep heating, in the absence of stretching, increases tissue extensibility more than superficial heating or no heating. Superficial heating is more effective than no heating, but the difference was not statistically significant.

An evaluation of safety guidelines to restrict exposure to stray radiofrequency radiation from short-wave diathermy units

Short-wave diathermy (SWD), a form of radiofrequency radiation used therapeutically by physiotherapists, may be applied in continuous (CSWD) or pulsed (PSWD) mode using either capacitive or inductive methods. Stray radiation emitted by these units may exceed exposure guidelines close to the equipment. Discrepant guidelines exist on a safe distance from an operating unit for operators and other personnel. Stray electric (E-field) and magnetic (H-field) field strengths from 10 SWD units in six departments were examined using a PMM 8053 meter and two isotropic probes (EP-330, HP-032). A 5 l saline phantom completed the patient circuit. Measurements were recorded in eight directions between 0.5 m and 2 m at hip and eye levels while the units operated at maximum output and data compared to current guidelines. Results found stray fields from capacitive CSWD fell below operator limits at 2 m (E-field 4.8-39.8 V/m; H-field 0.015-0.072 A/m) and at 1 m for inductive CSWD (E-field 0-36 V/m; H-field 0.01-0.065 A/m). Capacitive PSWD fields fell below the limits at 1.5 m (E-field 1.2-19.9 V/m; H-field 0.002-0.045 A/m) and at 1m for inductive PSWD (E-field 0.74.0 V/m; H-field 0.009-0.03 A/m). An extra 0.5 m was required before fields fell below the guidelines for other personnel. These results demonstrate, under a worst case scenario, emissions from SWD exceed the guidelines for operators at distances currently recommended as safe. Future guidelines should include recommendations for personnel other than physiotherapists.

Contraindications for superficial heat and therapeutic ultrasound: do sources agree?11No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the author(s) or on any organization with which the author(s) is/are associated

OBJECTIVES

To determine the amount of agreement among general rehabilitation sources for both superficial heating and therapeutic ultrasound contraindications.

DATA SOURCES

English-language textbook and peer-reviewed journal sources, from January 1992 to July 2002. Searches of computerized databases (HealthSTAR, CINAHL, MEDLINE, Embase) as well as Library of Congress Online Catalogs, Books in Print, and AcqWeb's Directory of Publishers and Venders.

DATA SELECTION

Sources were excluded if they (1) were published before 1992, (2) failed to address general rehabilitation audiences, or (3) were identified as a researcher's related publication with similar information on the topic.

DATA EXTRACTION

Type and number of contraindications, type of audience, year of publication, number of references, rationales, and alternative treatment strategies.

DATA SYNTHESIS

Eighteen superficial heat and 20 ultrasound sources identified anywhere from 5 to 22 and 9 to 36 contraindications/precautions, respectively. Agreement among sources was generally high but ranged from 11% to 95%, with lower agreement noted for pregnancy, metal implants, edema, skin integrity, and cognitive/communicative concerns. Seventy-two percent of superficial heat sources and 25% of ultrasound sources failed to reference at least 1 contraindication claim.

CONCLUSIONS

Agreement among contraindication sources was generally good for both superficial heat and therapeutic ultrasound. Sources varied with regard to the number of contraindications, references, and rationales cited. Greater reliance on objective data and standardized classification systems may serve to develop more uniform guidelines for superficial heat and therapeutic ultrasound.

A comparison of true and premodulated interferential currents

OBJECTIVE

To compare true and premodulated interferential currents (IFCs) in terms of sensory, motor, and pain thresholds; maximum electrically induced torque (MEIT); and comfort.

DESIGN

Repeated-measures design.

SETTING

Laboratory setting.

PARTICIPANTS

University student and staff volunteers.

INTERVENTIONS

Participants were exposed to 4 different conditions, chosen to evaluate 2 fundamental differences between true and premodulated IFCs. The conditions were different combinations of (1) premodulated or constant-amplitude currents applied at the skin and (2) crossed or parallel current paths.

MAIN OUTCOME MEASURES

Sensory, motor, and pain thresholds; MEIT; and subjective reports of relative discomfort were recorded for each of the 4 conditions. Motor to sensory threshold ratios were subsequently calculated to assess depth efficiency of stimulation.

RESULTS

The major findings were that crossed currents (true IFC) had no advantage over parallel currents (premodulated IFC) in terms of motor to sensory threshold ratio, MEIT, or comfort, and that premodulated currents produced higher torque values and less discomfort than constant-amplitude currents (true IFC). These results contradict the claimed superiority of true IFC.

CONCLUSIONS

The findings indicate that premodulated IFC, delivered via 2 large electrodes, may be clinically more effective than the traditional true IFC arrangement in terms of depth efficiency, torque production, and patient comfort.

Effects of electric stimulation on C and A delta fiber-mediated thermal perception thresholds 11No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors(s) or upon any organization with which the author(s) is/are associated

OBJECTIVE

To determine if interferential current (IFC) or transcutaneous electric nerve stimulation (TENS) alters C and A delta fiber-mediated thermal perception thresholds.

DESIGN

Single-blind, randomized controlled trial.

SETTING

Laboratory.

PARTICIPANTS

One hundred forty healthy women volunteers (mean age +/- standard deviation, 20.6+/-2.7 y).

INTERVENTIONS

Subjects were randomly and exclusively assigned to 1 of 7 groups (n=20 in each): 0, 5, and 100 Hz of IFC; 5 and 100 Hz of TENS; placebo and control stimulation. Stimulation was applied through 2 electrodes placed over the median nerve. Warm sensation, cold sensation, hot pain, and cold pain perception thresholds were measured from the thenar eminence by using a quantitative sensory testing device and a method of limits algorithm.

MAIN OUTCOME MEASURES

Warm sensation, cold sensation, hot pain, and cold pain thresholds (degrees C) before, during, and after stimulation.

RESULTS

There was a statistically significant effect of time for all 4 thermal perception thresholds (separate 2-way analyses of variance with repeated measures, all P<.001). There were no statistically significant differences between experimental groups, nor any interaction effects (all P>.05).

CONCLUSIONS

Neither IFC nor TENS altered C and A delta fiber-mediated thermal perception thresholds. The results suggest that any analgesic mechanisms with these modalities are likely to be complex.

An investigation into the analgesic effects of different frequencies of the amplitude-modulated wave of interferential current therapy on cold-induced pain in normal subjects 11No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the authors or any organization with which the authors are associated

OBJECTIVE

To investigate the analgesic effects of different amplitude-modulated frequencies of interferential current therapy (IFT) on cold-induced pain in healthy subjects.

DESIGN

Single-blind parallel group methodology was used. Subjects completed 6 cycles of the cold-induced pain test (2 pretreatment, 2 during treatment, 2 posttreatment). During each cycle, subjects plunged their hand into iced water and the time taken to reach pain threshold was recorded. The hand remained immersed in the iced water for a further 30 seconds, after which the self-reports of pain intensity and pain unpleasantness were recorded.

SETTING

Laboratory in the United Kingdom.

PARTICIPANTS

Sixty unpaid, pain-free volunteers without a known pathology that could cause pain.

INTERVENTIONS

IFT delivered on the nondominant arm at a "strong but comfortable" intensity without visible muscle twitches, using a quadripolar application technique at 1 of 6 possible amplitude modulated "beat" frequencies (20, 60, 100, 140, 180, 220Hz).

MAIN OUTCOME MEASURES

The percentage change in pain threshold, pain intensity, and pain unpleasantness from the pretreatment baseline.

RESULTS

Two-way repeated-measures analyses of variance found no effects for groups for pain threshold (P=.11) or pain ratings (P>.05). There were no effects for cycle for any of the outcome measures. Effects for group by cycle interaction were noted for pain intensity and unpleasantness ratings (P<.05), although post hoc analysis failed to determine the nature of this interaction.

CONCLUSIONS

Experimentally induced cold pain was not influenced by IFT frequencies.

Short-wave diathermy: current clinical and safety practices

BACKGROUND AND PURPOSE

Short-wave diathermy (SWD) is widely available, yet a comprehensive examination of current clinical practice remains absent from the literature. The present paper aims to assess clinical and safety issues in continuous (CSWD) and pulsed (PSWD) short-wave diathermy application and subsequently indicate areas for future research.

METHOD

A postal survey was carried out among 116 senior physiotherapists in 41 Irish hospital-based physiotherapy departments.

RESULTS

The response rate to the study was 75%. Analysis found that PSWD was the preferred mode of treatment with 27% of respondents using it more than once daily. Respondents considered both modes of treatment indicated for a variety of conditions. CSWD was rated as an effective treatment for chronic osteoarthritis, polyarthritis, non-specific arthrosis and haematomas. PSWD was reported an effective modality for acute soft tissue injury, haematomas, acute osteoarthritis, sinusitis and rheumatoid arthritis. Dose selection varied greatly but tended to be based on the type, nature and duration of the condition. Analysis of safety practices uncovered concerning findings. Although a high level of agreement was found on measures for patient safety, 30% of respondents reported that no measures for operator safety were taken and only five respondents stated they remained a specified distance from SWD equipment. Measures to ensure the safety of other personnel in the physiotherapy department were also lacking.

CONCLUSIONS

Given the availability of SWD equipment and its apparent efficacy in certain conditions, future research should aim to establish this by means of controlled clinical trials. The findings on safety practices underline the urgent need for comprehensive guidelines to ensure the safety of operators, patients and the general public during SWD application.

Occupational health in physiotherapy: general health and reproductive outcomes

Physiotherapists are exposed to many risk factors in their work environment. Their general health status is largely unknown, and conflicting studies suggest possible adverse reproductive effects of electromagnetic radiation to which they may be exposed. As part of a larger study, a systematic sample of one in four physiotherapists on a state register (N = 824) was surveyed. Each subject completed an eight page questionnaire, answering questions about musculoskeletal and general health, exposure to risk factors, exposure to electrophysical agents and reproductive outcomes. The response rate was 67.8%. The incidence of congenital malformations and miscarriage among physiotherapists was lower than that in the general community. However, physiotherapists who performed hydrotherapy were more likely to report dermatitis, rashes and fungal skin infections. The prevalence of these conditions increased with the number of hours spent doing hydrotherapy. These findings suggest that physiotherapists are unlikely to have an increased risk of negative reproductive outcomes because of their exposure to electrophysical agents. Physiotherapists who perform hydrotherapy, however, have an increased risk of skin complaints.