Pain in the Cancer Survivor.

Recent decades have demonstrated significant strides in cancer screening, diagnostics and therapeutics. As such there have been dramatic changes in survival following a diagnosis of cancer.

Neuromodulation techniques for cancer pain management.

PURPOSE OF REVIEW: Advanced pain management techniques may be indicated in 5-15% of cancer patients. Despite this, a recent review identified that, over the course of 1 year in England, only 458 patients received a procedure intended to provide analgesia and only 30 patients had intrathecal drug delivery (ITDD) devices implanted. This article describes the emerging evidence for ITDD in cancer pain and provides a narrative review of other neuromodulatory techniques (including spinal cord stimulation, peripheral nerve stimulation and acupuncture), approaches that might be employed to address this area of significant unmet clinical need. RECENT FINDINGS: Numerous studies have been published within the last year reporting positive outcomes associated with ITDD in cancer pain management. Neuromodulation represents an important strategy in the management of persistent pain. Whilst the nonmalignant pain evidence-base is rapidly growing, it remains sparse for cancer pain management. The growing cohort of cancer survivors may significantly benefit from neuromodulatory techniques. SUMMARY: ITDD and other neuromodulatory techniques for cancer pain management appear underutilised in the UK and offer the prospect of better treatment for cancer patients with refractory pain or intolerable side-effects from systemic analgesics.

Variability of radiological grading of blunt cerebrovascular injuries in trauma patients.

CONTEXT: Blunt cerebrovascular injury (BCVI) occurs in 1%-2% of all blunt trauma patients. Computed tomographic angiography of the neck (CTAn) is commonly used for the diagnosis and grading of BCVIs. Grade of injury dictates treatment, and there remains a lack in understanding the inter-reader reliability of these interpretations. AIMS: The aim of this study is to determine the extent of variability in BCVIs among specialized neuroradiologist interpretation of CTAn. SETTINGS AND DESIGN: Retrospective review of trauma patients admitted to a level one trauma center with a BCVI from January 2012 to December 2017. Patients were randomly assigned for CTAn re-evaluation by two of three blinded, neuroradiologists. STATISTICAL ANALYSIS USED: The variability in BCVI grades was measured using the coefficient of unalikeability (u), and inter-reader reliability was calculated using weighted Cohen's kappa (k). RESULTS: Two hundred and twenty-eight BCVIs were analyzed with initial grades of 71 (31%) grade one, 74 (32%) grade two, 26 (11%) grade three, 57 (25%) grade four, and 0 grade five. Variability was present in 93 (41%) of all BCVIs. Grade one injuries had the lowest occurrence of total agreement (31%) followed by grade three (61%), grade two (63%), and grade four (92%). Total variability of grade interpretations (u = 100) occurred most frequently with grade three BCVIs (21%). Weighted Cohen's k calculations had a mean of 0.07, indicating poor reader agreement. CONCLUSIONS: This novel study demonstrated the BCVI variability of radiological grade interpretation occurs in more than a third of patients. The reliability of CTAn interpretation of BCVI grades is not uniform, potentially leading to undertreatment and overtreatment.

Metabolic Fingerprinting Links Oncogenic PIK3CA with Enhanced Arachidonic Acid-Derived Eicosanoids.

Oncogenic transformation is associated with profound changes in cellular metabolism, but whether tracking these can improve disease stratification or influence therapy decision-making is largely unknown. Using the iKnife to sample the aerosol of cauterized specimens, we demonstrate a new mode of real-time diagnosis, coupling metabolic phenotype to mutant PIK3CA genotype. Oncogenic PIK3CA results in an increase in arachidonic acid and a concomitant overproduction of eicosanoids, acting to promote cell proliferation beyond a cell-autonomous manner. Mechanistically, mutant PIK3CA drives a multimodal signaling network involving mTORC2-PKCζ-mediated activation of the calcium-dependent phospholipase A2 (cPLA2). Notably, inhibiting cPLA2 synergizes with fatty acid-free diet to restore immunogenicity and selectively reduce mutant PIK3CA-induced tumorigenicity. Besides highlighting the potential for metabolic phenotyping in stratified medicine, this study reveals an important role for activated PI3K signaling in regulating arachidonic acid metabolism, uncovering a targetable metabolic vulnerability that largely depends on dietary fat restriction. VIDEO ABSTRACT.

Effectiveness of a Posterior Shoulder Stretching Program on University-Level Overhead Athletes: Randomized Controlled Trial.

OBJECTIVE: To determine whether a posterior shoulder stretch was effective in increasing internal rotation (IR) and horizontal adduction (HAd) range of motion (ROM) in overhead athletes identified as having reduced mobility. DESIGN: Randomized controlled trial (parallel design). SETTING: University-based sports medicine clinic. PARTICIPANTS: Thirty-seven university-level athletes in volleyball, swimming, and tennis, with IR ROM deficits ≥15°, were randomized into intervention or control groups. No subjects withdrew or were lost to follow-up. INTERVENTION: The intervention group performed the "sleeper stretch" daily for 8 weeks, whereas the control group performed usual activities. MAIN OUTCOME MEASURES: Independent t tests determined whether IR and HAd ROM differences between groups were significant at 8 weeks and 2-way repeated-measures analysis of variance tests measured the rate of shoulder ROM change. Subject-reported shoulder pain and function were obtained at each evaluation. RESULTS: Significant differences were found between the intervention and control groups' IR and HAd ROM at 8 weeks (P < 0.001 and P = 0.003, respectively) compared with baseline (zero weeks) (P = 0.19 and P = 0.82, respectively). Significant improvements in IR were detected in the intervention group at 4 weeks (P < 0.001), whereas HAd demonstrated significant changes only at 8 weeks (P = 0.003). Reported shoulder function (P = 0.002) was different between study groups at 8 weeks. CONCLUSION: Overhead, university-level athletes with an IR deficit ≥15° significantly increased their IR and HAd ROM after performing a posterior shoulder stretch for 8 weeks. CLINICAL RELEVANCE: Effective management of posterior shoulder tightness through stretching may reduce the incidence of shoulder pathology in overhead athletes.

Sustainability of outcomes after a randomized crossover trial of resistance exercise for shoulder dysfunction in survivors of head and neck cancer.

PURPOSE: Shoulder pain and dysfunction may occur after surgery for head and neck cancer (HNC) as a result of damage to or resection of the spinal accessory nerve. Previous research found that 12 weeks of upper extremity progressive resistance exercise training (PRET) improved shoulder outcomes in survivors of HNC; the purpose of this study was to determine whether benefits persisted over the longer term. METHODS: Survivors of HNC were assigned at random to PRET (n=27) or a standard therapeutic protocol (TP; n=25), with an opportunity for crossover in the TP group after 12 weeks. At 12-month follow-up, participants were mailed a questionnaire that assessed quality of life (QOL), shoulder outcomes, and exercise behaviour. RESULTS: Of the 52 participants enrolled in the study, 44 were eligible at 12-month follow-up, and 37 (71%) completed the questionnaires. Overall, self-reported outcomes were largely sustained over the follow-up period. After 12 months, regardless of original group allocation, participants who continued resistance exercise training during the follow-up period reported better neck dissection-related functioning (p=0.021) and better QOL (p=0.011) than those who did not. CONCLUSIONS: Benefits of PRET were sustained at 12-month follow-up. Ongoing participation in resistance exercise training may prove valuable as a supportive care intervention for survivors of HNC.

Objet : Une douleur à l'épaule et une dysfonction peuvent faire leur apparition après une intervention chirurgicale pour un cancer de la tête et du cou (CTC) parce que le nerf spinal accessoire a été endommagé ou réséqué. Des recherches antérieures ont révélé que 12 semaines d'exercice contre résistance progressive (ERP) des membres supérieurs amélioraient le résultat pour l'épaule chez les survivants d'un CTC. Cette étude visait à déterminer si les bienfaits persistaient à long terme. Méthodes : Les survivants d'un CTC ont été répartis au hasard pour suivre un programme d'ERP (n=27) ou un protocole thérapeutique habituel (PT; n=25) et ont pu passer au groupe PT après 12 semaines. Au suivi à 12 mois, on a envoyé par la poste aux participants un questionnaire d'évaluation de la qualité de vie (QDV), des résultats pour l'épaule et du comportement lié à l'exercice. Résultats : Sur les 52 participants inscrits à l'étude, 44 étaient admissibles au suivi à 12 mois et 37 (71 %) ont répondu aux questionnaires. Dans l'ensemble, les résultats autodéclarés ont été maintenus en grande partie au cours de la période de suivi. Après 12 mois, sans égard à leur affectation au groupe original, les participants qui ont poursuivi leur entraînement par l'exercice à résistance au cours de la période de suivi ont signalé un meilleur fonctionnement lié à la dissection subie au cou (p=0,021) et une meilleure QDV (p=0,011) que ceux qui ne l'ont pas fait. Conclusions : Les bienfaits de l'ERP persistaient au suivi à 12 mois. La participation continue à un programme d'exercice contre résistance peut se révéler utile comme soins de soutien pour les survivants d'un CTC.

Enhanced therapeutic alliance modulates pain intensity and muscle pain sensitivity in patients with chronic low back pain: an experimental controlled study.

BACKGROUND: Physical therapy influences chronic pain by means of the specific ingredient of an intervention as well as contextual factors including the setting and therapeutic alliance (TA) between provider and patient. OBJECTIVE: The purpose of this study was to compare the effect of enhanced versus limited TA on pain intensity and muscle pain sensitivity in patients with chronic low back pain (CLBP) receiving either active or sham interferential current therapy (IFC). DESIGN: An experimental controlled study with repeated measures was conducted. Participants were randomly divided into 4 groups: (1) AL (n=30), which included the application of active IFC combined with a limited TA; (2) SL (n=29), which received sham IFC combined with a limited TA; (3) AE (n=29), which received active IFC combined with an enhanced TA; and (4) SE (n=29), which received sham IFC combined with an enhanced TA. METHODS: One hundred seventeen individuals with CLBP received a single session of active or sham IFC. Measurements included pain intensity as assessed with a numerical rating scale (PI-NRS) and muscle pain sensitivity as assessed via pressure pain threshold (PPT). RESULTS: Mean differences on the PI-NRS were 1.83 cm (95% CI=14.3-20.3), 1.03 cm (95% CI=6.6-12.7), 3.13 cm (95% CI=27.2-33.3), and 2.22 cm (95% CI=18.9-25.0) for the AL, SL, AE, and SE groups, respectively. Mean differences on PPTs were 1.2 kg (95% CI=0.7-1.6), 0.3 kg (95% CI=0.2-0.8), 2.0 kg (95% CI=1.6-2.5), and 1.7 kg (95% CI=1.3-2.1), for the AL, SL, AE, and SE groups, respectively. LIMITATIONS: The study protocol aimed to test the immediate effect of the TA within a clinical laboratory setting. CONCLUSIONS: The context in which physical therapy interventions are offered has the potential to dramatically improve therapeutic effects. Enhanced TA combined with active IFC appears to lead to clinically meaningful improvements in outcomes when treating patients with CLBP.

Predictors of adherence to an exercise program for shoulder pain and dysfunction in head and neck cancer survivors.

PURPOSE: Achieving acceptable levels of adherence to exercise may be a challenge with head and neck cancer (HNC) survivors given the high morbidity associated with treatment. The purpose of the present trial was to identify the key predictors of adherence during our shoulder exercise rehabilitation trial. METHODS: Fifty-two HNC survivors were randomly assigned to a 12-week progressive resistance exercise training protocol (n = 27) or a standardized therapeutic exercise protocol (n = 25) that was prescribed to address shoulder pain and dysfunction. Baseline data were collected on standard demographic, medical, behavioral, symptom, psychosocial, and motivational variables from the theory of planned behavior. RESULTS: The exercise adherence rate for the trial was 91%. In multivariate analysis, the independent predictors of reduced adherence were undergoing a more extensive neck dissection procedure (ß = -0.361; P = 0.007) and reporting daily alcohol consumption (ß = -0.298; P = 0.031). Higher exercise adherence was achieved by HNC participants who had undergone nerve sparing neck dissection procedures and who were not regular drinkers. CONCLUSION: Excellent adherence to exercise was achieved in the trial despite high morbidity associated with HNC treatment. The high adherence achieved was likely due to the select and highly motivated sample of HNC survivors as well as to factors associated with trial design such as the support offered to participants. The findings of this trial need to be further explored and confirmed in a larger study that includes a more diverse sample of HNC survivors.

Patients with temporomandibular disorders have increased fatigability of the cervical extensor muscles.

OBJECTIVES: To determine whether patients with myogenous and mixed temporomandibular disorders (TMD) have greater fatigability of the cervical extensor muscles while performing a neck extensor muscle endurance test (NEMET) when compared with healthy controls. METHODS: A total of 151 individuals participated in this study. Of these 47 were healthy controls, 57 patients had myogenous TMD, and 47 patients had mixed TMD. All patients performed the NEMET. The patients were instructed to maintain a prone lying position with the neck unsupported as long as possible, stopping at signs of fatigue or any discomfort. Electromyographic activity of the cervical extensor muscles during the NEMET and the holding time were collected for all patients and were compared across groups. A 1-way analysis of variance was used to evaluate the differences in holding time between patients with TMD and healthy controls. A mixed model analysis was used to evaluate the differences in normalized median frequency at different times (fatigue index) for the cervical extensor muscles while performing the NEMET between patients with TMD and controls. RESULTS: There were statistically significant differences (P<0.05) in the slopes of the normalized median frequency between patients with TMD and healthy controls at 10, 30, 40, 50, 60, 70, 80, 90, and 100 seconds of the NEMET. Holding time was significantly reduced in both patients with myogenous TMD and mixed TMD when compared with healthy controls (P<0.05). DISCUSSION: These results highlight the fact that alterations of endurance capacity of the extensor cervical muscles could be implicated in the neck-shoulder disturbances presented in patients with TMD.

A preliminary investigation into the effects of active interferential current therapy and placebo on pressure pain sensitivity: a random crossover placebo controlled study.

OBJECTIVE: (1) To determine the effect of active and placebo interferential current on muscle pain sensitivity using an experimental mechanically induced pain model. (2) To evaluate the predictive role of expectations, gender, baseline muscle pain sensitivity, and intervention order on placebo response. DESIGN: Randomized placebo controlled cross-over trial. SETTING: University research laboratory. PARTICIPANTS: Forty healthy volunteers (20 females, 20 males). INTERVENTIONS: Active interferential current, placebo (sham) interferential current, and no treatment/control were applied to the lumbar area on different days. MAIN OUTCOMES MEASURES: Pressure pain thresholds and placebo response. RESULTS: The two-way ANOVA with repeated measures analysis determined a significant interaction between condition and time (P=0.002). Pairwise comparisons found differences between active interferential and the control condition at 15 minutes into treatment (mean difference=0.890 kg/cm(2), 95% CI 0.023 to 1.757, P=0.043) and at 30 minutes into treatment (mean difference=0.910 kg/cm(2), 95% CI 0.078 to 1.742, P=0.028). The increase in pressure pain thresholds between the active interferential and the control condition (1.12 kg/cm(2)) was clinically meaningful. Logistic regression analysis showed that the condition sequence order was the only variable that predicted placebo response (odds ratio 9.7; P=0.028). If a subject started the sequence receiving placebo treatment first, the odds of responding to placebo would be approximately 10 times higher (i.e. 90% probability of being a placebo responder) than that of starting with an active treatment. CONCLUSIONS: Active interferential was more efficient than control condition in decreasing muscle pain sensitivity. Placebo interferential was not significantly different from control. Treatment sequence demonstrated a strong association with placebo response. These findings have implications for future research characterizing and identifying placebo responders in physiotherapy.

Head and cervical posture in patients with temporomandibular disorders.

AIM: To determine whether patients with myogenous or mixed (ie, myogeneous plus arthrogeneous) temporomandibular disorders (TMD) had different head and cervical posture measured through angles commonly used in clinical research settings when compared to healthy individuals. METHODS: One hundred fifty-four persons participated in this study. Of these, 50 subjects were healthy, 55 subjects had myogenous TMD, and 49 subjects had mixed TMD (ie, arthrogenous plus myogenous TMD). A lateral photograph was taken with the head in the self-balanced position. Four angles were measured in the photographs: (1) Eye-Tragus-Horizontal, (2) Tragus-C7-Horizontal, (3) Pogonion-Tragus-C7, and (4) Tragus-C7-Shoulder. Alcimagen software specially designed to measure angles was used in this study. All of the measurements were performed by a single trained rater, a dental specialist in orthodontics, blinded to each subject's group status. RESULTS: The only angle that reached statistical significance among groups was the Eye-Tragus-Horizontal (F = 3.03, P = .040). Pairwise comparisons determined that a mean difference of 3.3 degrees (95% confidence intervals [CI]: 0.15, 6.41) existed when comparing subjects with myogenous TMD and healthy subjects (P = .036). Postural angles were not significantly related to neck disability, jaw disability, or pain intensity. Intrarater and interrater reliability of the measurements were excellent, with intraclass correlation coefficient (ICC) values ranging between 0.996-0.998. CONCLUSION: The only statistically significant difference in craniocervical posture between patients with myogenous TMD and healthy subjects was for the Eye-Tragus-Horizontal angle, indicating a more extended position of the head. However, the difference was very small (3.3 degrees) and was judged not to be clinically significant.

Clinical relevance vs. statistical significance: Using neck outcomes in patients with temporomandibular disorders as an example.

Statistical significance has been used extensively to evaluate the results of research studies. Nevertheless, it offers only limited information to clinicians. The assessment of clinical relevance can facilitate the interpretation of the research results into clinical practice. The objective of this study was to explore different methods to evaluate the clinical relevance of the results using a cross-sectional study as an example comparing different neck outcomes between subjects with temporomandibular disorders and healthy controls. Subjects were compared for head and cervical posture, maximal cervical muscle strength, endurance of the cervical flexor and extensor muscles, and electromyographic activity of the cervical flexor muscles during the CranioCervical Flexion Test (CCFT). The evaluation of clinical relevance of the results was performed based on the effect size (ES), minimal important difference (MID), and clinical judgement. The results of this study show that it is possible to have statistical significance without having clinical relevance, to have both statistical significance and clinical relevance, to have clinical relevance without having statistical significance, or to have neither statistical significance nor clinical relevance. The evaluation of clinical relevance in clinical research is crucial to simplify the transfer of knowledge from research into practice. Clinical researchers should present the clinical relevance of their results.

Electromyographic activity of the cervical flexor muscles in patients with temporomandibular disorders while performing the craniocervical flexion test: a cross-sectional study.

BACKGROUND: Most patients with temporomandibular disorders (TMD) have been shown to have cervical spine dysfunction. However, this cervical dysfunction has been evaluated only qualitatively through a general clinical examination of the cervical spine. PURPOSE: The purpose of this study was to determine whether patients with TMD had increased activity of the superficial cervical muscles when performing the craniocervical flexion test (CCFT) compared with a control group of individuals who were healthy. DESIGN: A cross-sectional study was conducted. METHODS: One hundred fifty individuals participated in this study: 47 were healthy, 54 had myogenous TMD, and 49 had mixed TMD. All participants performed the CCFT. Data for electromyographic activity of the sternocleidomastoid (SCM) and anterior scalene (AS) muscles were collected during the CCFT for all participants. A 3-way mixed-design analysis of variance for repeated measures was used to evaluate the differences in EMG activity for selected muscles while performing the CCFT under 5 incremental levels. Effect size values were calculated to evaluate the clinical relevance of the results. RESULTS: Although there were no statistically significant differences in electromyographic activity in the SCM or AS muscles during the CCFT in patients with mixed and myogenous TMD compared with the control group, those with TMD tended to have increased activity of the superficial cervical muscles. LIMITATIONS: The results obtained in this research are applicable for the group of individuals who participated in this study under the protocols used. They could potentially be applied to people with TMD having characteristics similar to those of the participants of this study. CONCLUSION: This information may give clinicians insight into the importance of evaluation and possible treatment of the deep neck flexors in patients with TMD. However, future research should test the effectiveness of this type of program through a randomized controlled trial in people with TMD in order to determine the real value of treating this type of impairment in this population.

Effects of exercise therapy on endogenous pain-relieving peptides in musculoskeletal pain: a systematic review.

OBJECTIVE: To review the literature regarding the effects of exercise in patients with musculoskeletal pain on modifying: (1) the plasma or cerebral spinal fluid concentrations of pain-relieving peptides and (2) changing the cerebral activity of areas linked with pain processing and modulation systematically. METHODS: An extensive search of bibliographic databases including MEDLINE, EMBASE, EBM Reviews-Cochrane Central Register of Controlled Trials, ISI Web of Science, Scopus, PeDro, AMED, and CINAHL was made. Two independent investigators screened the titles of publications and completed quality assessment of the selected studies. RESULTS: The search of the literature resulted in a total of 1819 published studies. Of these only 1 study of low methodological quality was considered to be relevant. The agreement between reviewers to select the articles was κ=1. The agreement for the methodological quality evaluation was κ=0.9. DISCUSSION: Given the small number of studies identified and the low quality of research, no firm conclusions could be reached about the impact of therapeutic exercise on modifying concentrations of pain-relieving peptides or its effect on changing the cerebral activity of areas linked with pain processing in patients with musculoskeletal pain. There is a clear need for well-designed trials examining exercise therapy interventions and their effect on both pain-relieving peptides and cerebral activity in patients with musculoskeletal pain.

Reduced endurance of the cervical flexor muscles in patients with concurrent temporomandibular disorders and neck disability.

Subjects with temporomandibular disorders (TMDs) have been found to have clinical signs and symptoms of cervical dysfunction. Although many studies have investigated the relationship between the cervical spine and TMD, no study has evaluated the endurance capacity of the cervical muscles in patients with TMD. Thus the objective of this study was to determine whether patients with TMD had a reduced endurance of the cervical flexor muscles at any level of muscular contraction when compared with healthy subjects. One hundred and forty-nine participants provided data for this study (49 subjects were healthy, 54 had myogenous TMD, and 46 had mixed TMD). There was a significant difference in holding time at 25% MVC between subjects with mixed TMD when compared to subjects with myogenous TMD and healthy subjects. This implies that subjects with mixed TMD had less endurance capacity at a lower level of contraction (25% MVC) than healthy subjects and subjects with myogenous TMD. No significant associations between neck disability, jaw disability, clinical variables and neck flexor endurance test were found.

Is maximal strength of the cervical flexor muscles reduced in patients with temporomandibular disorders?

OBJECTIVE: To determine whether there was a difference in maximal cervical flexor muscle strength in subjects with temporomandibular disorders (mixed and myogenous) compared with healthy subjects. DESIGN: Cross-sectional study. SETTING: Orthopedics/sports laboratory at the University of Alberta. PARTICIPANTS: Subjects (N=149) of whom 50 were healthy, 54 had myogenous temporomandibular disorders (TMD), and 45 had mixed TMD. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Maximal cervical flexor strength, pain. RESULTS: There was no statistically significant difference in maximal cervical flexor strength among groups (P>.05). Subjects' body weight was significantly associated with strength. No significant association between jaw disability with maximal cervical flexor strength was found. A significant but weak association between neck disability and maximal cervical flexors strength was found. CONCLUSIONS: These results indicated that strength evaluation is one of several assessment factors that need to be addressed when evaluating musculoskeletal painful conditions such as TMD and neck disorders, but strength evaluation cannot be considered as a direct measure of disability. Future studies should explore evaluation of strength in other muscular groups such as cervical extensors, rotators, and lateral flexors, and also under different conditions such as rapid movements, and in patients with more severe jaw disability.

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.

Does amplitude-modulated frequency have a role in the hypoalgesic response of interferential current on pressure pain sensitivity in healthy subjects? A randomised crossover study.

OBJECTIVE: To investigate the hypoalgesic effect of amplitude-modulated frequency during interferential current therapy using an experimentally induced mechanical pain model in normal subjects. This study examined pain pressure sensitivities achieved when the amplitude-modulated frequency parameter was present (100Hz) and absent (0Hz). DESIGN: Randomised controlled crossover trial with repeated measures. SETTING: University research laboratory. PARTICIPANTS: Forty-six healthy volunteers (23 males, 23 females). INTERVENTIONS: Two interferential therapy protocols (with and without amplitude-modulated frequencies) were applied to the lumbar area on two different days. MAIN OUTCOME MEASURES: Pressure pain thresholds over the lumbar area were measured before, during and after application of the interferential therapy protocols. RESULTS: A three-way analysis of variance with repeated measures failed to show any statistically significant difference between the two protocols in modifying pressure pain threshold values (mean difference 0.017kg/cm(2), 95% confidence interval -0.384 to 0.350, P=0.93). Statistically significant differences were identified (P<0.001) between measurements, indicating a comparable decrease in pain sensitivity in both groups. However, the increase in pressure pain thresholds (0.76kg/cm(2)) failed to reach a level of clinical importance. CONCLUSIONS: The addition of an amplitude-modulated frequency parameter to interferential therapy did not influence mechanical pain sensitivity in healthy subjects. Amplitude-modulated frequency is therefore unlikely to have a physiological hypoalgesic effect.

Reliability of scapular positioning measurement procedure using the palpation meter (PALM).

BACKGROUND AND OBJECTIVES: Observation and measurement of the static position of the scapula is important for investigating both shoulder and neck pathology. Measurement of scapular position is complex and lacks a clinically useful instrument. The objective of this study was to investigate the reliability of the Palpation Meter (PALM) for measuring scapular position when the glenohumeral joint is held in various positions. METHODS: Thirty normal subjects were recruited for a test-retest reliability study. Three raters conducted measurements on two different occasions to estimate intra- and inter-rater reliability. The scapular positions evaluated in this study were: (1) the horizontal distance between the scapula and the spine in the scapular resting position and during elevation of the arm in the scapular plane; and (2) the vertical distance between C(7) and the acromion (C(7)-A). Intraclass correlation coefficient (ICC), standard error of measurement (SEM) and Bland and Altman limits of agreement were calculated. RESULTS: Reliability values for measurements of the horizontal distance between the scapula and the spine were generally good for both intra-rater (ICC 0.81 to 0.89; SEM 0.56 to 1.17cm) and inter-rater (ICC 0.67 to 0.89; SEM 0.59 to 0.98cm) evaluation. Reliability values of measurement of depression of the acromion were also good for both intra-rater (ICC 0.72 to 0.78; SEM 0.66 to 0.79) and inter-rater (ICC 0.76; SEM 0.64) evaluation. No systematic bias was observed with Bland and Altman analysis. CONCLUSIONS: The PALM is a reliable tool for the measurement of scapular positioning in a healthy sample. Future studies should be conducted to further investigate the clinometric properties of the PALM in patient populations before its clinical usefulness for measuring scapular position can be established.