Weight loss interventions for adults with overweight/obesity and chronic musculoskeletal pain: a mixed methods systematic review.

Worldwide prevalence of adult overweight and obesity is a growing public health issue. Adults with overweight/obesity often have chronic musculoskeletal pain. Using a mixed-methods review, we aimed to quantify the effectiveness and explore the appropriateness of weight loss interventions for this population. Electronic databases were searched for studies published between 01/01/90 and 01/07/16. The review included 14 randomized controlled trials that reported weight and pain outcomes and three qualitative studies that explored perceptions of adults with co-existing overweight/obesity and chronic musculoskeletal pain. The random-effects pooled mean weight loss was 4.9 kg (95%CI:2.9,6.8) greater for intervention vs control. The pooled mean reduction in pain was 7.3/100 units (95%CI:4.1,10.5) greater for intervention vs control. Study heterogeneity was substantial for weight loss (I2  = 95%, tau = ±3.5 kg) and pain change (I2  = 67%, tau = ±4.1%). Meta-regression slopes for the predictors of study quality, mean age and baseline mean weight on mean study weight reduction were shallow and not statistically significant (P > 0.05). The meta-regression slope between mean pain reduction and mean weight lost was shallow, and not statistically significant, -0.09 kg per unit pain score change (95%CI:-0.21,0.40, P = 0.54). Meta-synthesis of qualitative findings resulted in two synthesized findings; the importance of healthcare professionals understanding the effects of pain on ability to control weight and developing management/education programmes that address comorbidity.

The effect of visual feedback of body parts on pain perception: A systematic review of clinical and experimental studies.

The aim of this systematic review was to evaluate the effect of visual feedback techniques on pain perception by analysing the effect of normal-sized, magnified or minified visual feedback of body parts on clinical and experimentally-induced pain. Databases searched: Medline, Embase, PsychInfo, PEDro, CINAHL, CENTRAL and OpenSIGLE. Studies investigating pain patients and pain-free participants exposed to experimentally-induced pain were analysed separately. Risk of bias was assessed and data were meta-analysed. Thirty four studies were included. A meta-analysis of clinical data favoured mirror visual feedback (six trials; mean difference = -13.06 mm; 95% CI = -23.97, -2.16). Subgroup analysis favoured mirror visual feedback when used as a course of treatment (three trials; mean difference = -12.76 mm; 95% CI = -24.11, -1.40) and when used for complex regional pain syndrome for complex regional pain syndrome (three trials; standard mean difference = -1.44; 95% CI = -1.88, -0.99). There is insufficient evidence to determine differences between normal-sized view and a size-distorted view of the limb. Mirror visual feedback was not superior to object view or direct view of the hand for reducing experimental pain in pain-free participants. There were inconsistencies in study findings comparing normal-sized reflection of a body part and a reflection of an object, or a magnified or minified reflection. There is tentative evidence that mirror visual feedback can alleviate pain when delivered as a course of treatment, and for patients with complex regional pain syndrome. It was not possible to determine whether normal-sized, magnified or minified visual feedback of body parts affects pain perception because of contradictory findings in primary studies. SIGNIFICANCE: It was not possible to determine whether normal-sized, magnified or minified visual feedback of body parts affected pain perception in clinical or experimental settings because of contradictory findings in primary studies. This emphasizes the need for higher quality studies.

Changing the size of a mirror-reflected hand does not affect pain perception: A repeated measures study on healthy human participants.

BACKGROUND: Studies suggest that observing magnified and minified body parts using mirrors, lenses and virtual reality may affect pain perception. However, the direction of effect varies between studies. The aim of the present study was to evaluate the effect of observing a normal-sized, magnified and minified reflection of a hand on perceptual embodiment and contact-heat stimuli. METHODS: Participants (n = 46) observed a normal-sized, magnified and minified reflection of the hand and a no-reflection condition while performing synchronized finger movements for 3 min (adaptive phase). Measurements of embodiment were taken before adaptive phase, pre- and post-contact-heat stimuli. RESULTS: There were no differences in pain threshold nor tolerance between reflection and no-reflection conditions. Altering the size of the reflection of the hand did not affect estimates of pain threshold nor tolerance. The temperature for warm detection threshold was lower when participants were observing the magnified reflection of the hand compared with the no-reflection condition. Perceptual embodiment of the reflection of the hand was stronger after an adaptive phase with visuo-motor feedback, and the painful stimuli did not weaken the perceptual experience. CONCLUSION: Observing a reflection of the hand in front of a mirror did not alter heat pain threshold nor tolerance when compared with a no-reflection condition, and altering the size of the reflection did not affect pain perception. Researchers and clinicians using visual feedback techniques may consider including an adaptive phase with visuo-motor feedback to facilitate embodiment of the viewed body part. SIGNIFICANCE: An adaptive phase with visuo-motor feedback enhances the perceptual experience of embodiment of a reflection of a hand and a painful stimulus does not weaken the experience. This should be considered when using visual feedback techniques for pain management.

Body mass index and distribution of body fat can influence sensory detection and pain sensitivity.

BACKGROUND: The aim of this study was to investigate the influence of body fat percentage and its distribution on sensory detection and pain sensitivity responses to experimentally induced noxious stimuli in otherwise pain-free individuals. METHODS: Seventy-two participants were divided into three equal groups according to their body mass index (BMI: normal, overweight and obese). Percentage body fat was estimated using a four-site skinfold method. Measurements of cold pressor pain threshold, tolerance and intensity; contact thermal sensory detection and heat pain threshold and tolerance (TSA-II - NeuroSensory Analyzer, Medoc); and blunt pressure pain threshold (algometer, Somedic SenseLab AB) were taken at the waist and thenar eminence. RESULTS: Mean ± SD pressure pain threshold of the obese group (620.72 ± 423.81 kPa) was significantly lower than normal (1154.70 ± 847.18 kPa) and overweight (1285.14 ± 998.89 kPa) groups. Repeated measures ANOVA found significant effects for site for cold detection threshold (F1,68  = 8.3, p = 0.005) and warm detection threshold (F1,68  = 38.69, p = 0.001) with waist having lower sensory detection thresholds than thenar eminence. For heat pain threshold, there were significant effects for site (F1,68  = 4.868, p = 0.031) which was lower for waist compared with thenar eminence (mean difference = 0.89 °C). CONCLUSION: Obese individuals were more sensitive than non-obese individuals to pressure pain but not to thermal pain. Body sites may vary in their response to different types and intensities of stimuli. The inconsistency of findings within and between research studies should catalyse further research in this field. SIGNIFICANCE: This study provided evidence that body mass index and distribution of body fat can influence sensory detection and pain sensitivity. Obese individuals were more sensitive than normal range body mass index individuals to pressure pain but not to thermal pain. Pain response varied according to subcutaneous body fat at different body sites. These findings strengthen arguments that weight loss should be a significant aspect of a pain management programme for obese pain patients.

Age-related changes in pain sensitivity in healthy humans: A systematic review with meta-analysis.

Literature suggests that pain perception diminishes in old age. The most recent review used search strategies conducted over a decade ago and concluded that study findings were equivocal. The aim of this systematic review, with meta-analysis, was to determine age-related changes in pain sensitivity in healthy pain-free adults, children and adolescents. A search of PubMed, Science Direct, and PsycINFO identified studies that compared pain sensitivity response to noxious stimuli at different time points in the lifespan of healthy individuals. Selected studies were assessed for methodological quality and data pooled and meta-analysed. Publication bias was tested using Funnel plots. Twelve studies were included in the review (study sample sizes 30-244 participants). Seven of nine studies found statistically significant differences in pain sensitivity response between old (mean ± SD 62.2 ± 3.4 to 79 ± 4 years) and younger adults (22 ± 1.5 to 39.1 ± 8.8 years), but the direction of change was inconsistent. Meta-analysis found that pressure pain threshold was lower in old adults compared with younger adults (p = 0.018, I2  = 60.970%). There were no differences in contact heat pain thresholds between old and younger adults (p = 0.0001, I2  = 90.23%). Three studies found that younger children (6-8.12 years) were more sensitive to noxious stimuli than older children (9-14 years). Methodological quality of studies was high, with a low risk of publication bias. There was substantial statistical and methodological heterogeneity. There is tentative evidence that pressure pain threshold was lower in old adults compared with younger adults, with no differences in heat pain thresholds. Further studies are needed. SIGNIFICANCE: There is tentative evidence that old adults may be more sensitive to mechanically-evoked pain but not heat-evoked pain than young adults. There is a need for further studies on age-related changes in pain perception.

Effects of ethnicity and gender role expectations of pain on experimental pain: a cross-cultural study.

BACKGROUND: Gender role expectations of pain (GREP) have been shown to mediate sex differences in experimental pain. Few studies have investigated the role of ethnicity in shaping GREP. The aim of this study was to examine interactions between ethnicity and GREP on experimentally induced pressure and ischaemic pain in Libyan and white British students in their respective countries. METHODS: Libyan (n = 124) and white British (n = 51) students completed a GREP questionnaire and their response to experimental pain was measured. Blunt pressure pain threshold (PPT) was measured over the 1st interosseous muscle using algometry. Pain intensity and pain unpleasantness (100 mm visual analogue scale) were measured at 1-min intervals during a submaximal effort tourniquet test on the forearm. RESULTS: Multivariate analysis of variance detected significant effects for Sex and Ethnicity on pain measurements. Men had higher PPTs than women (p < 0.001). Libyans had higher PPTs than white British participants (p < 0.001). There were significant effects for Sex and Ethnicity for pain intensity ratings (p < 0.01) but no significant differences between the sexes in pain unpleasantness (p > 0.05). Libyan participants had higher pain intensity (p < 0.01) and pain unpleasantness (p < 0.05) ratings compared with white British participants. There were effects for Sex and Ethnicity for all GREP dimensions. Libyan participants exhibited stronger stereotypical views in GREP than white British participants (p < 0.001). CONCLUSIONS: GREP was the mediator of sex but not ethnic differences in pain report, suggesting that gender stereotypical attitudes to pain account for differences in pain expression between men and women.

Gender role affects experimental pain responses: a systematic review with meta-analysis.

Gender role refers to the culturally and socially constructed meanings that describe how women and men should behave in certain situations according to feminine and masculine roles learned throughout life. The aim of this meta-analysis was to evaluate the relationship between gender role and experimental pain responses in healthy human participants. We searched computerized databases for studies published between January 1950 and May 2011 that had measured gender role in healthy human adults and pain response to noxious stimuli. Studies were entered into a meta-analysis if they calculated a correlation coefficient (r) for gender role and experimental pain. Searches yielded 4465 'hits' and 13 studies were eligible for review. Sample sizes were 67-235 participants and the proportion of female participants was 45-67%. Eight types of gender role instrument were used. Meta-analysis of six studies (406 men and 539 women) found a significant positive correlation between masculine and feminine personality traits and pain threshold and tolerance, with a small effect size (r = 0.17, p = 0.01). Meta-analysis of four studies (263 men and 297 women) found a significant negative correlation between gender stereotypes specific to pain and pain threshold and tolerance, with a moderate effect size (r = -0.41, p < 0.001). In conclusion, individuals who considered themselves more masculine and less sensitive to pain than the typical man showed higher pain thresholds and tolerances. Gender stereotypes specific to pain scales showed stronger associations with sex differences in pain sensitivity response than masculine and feminine personality trait scales.

Gender role expectations of pain mediate sex differences in cold pain responses in healthy Libyans.

Previous studies found a relationship between response to experimentally-induced pain and scores for the gender role expectations of pain (GREP) questionnaire. Findings were similar in individuals from America, Portugal and Israel suggesting that gender role expectations may be universal. The aim of this study was to translate and validate Arabic GREP using Factor Analysis and to investigate if sex differences to cold-pressor pain in healthy Libyan men and women are mediated through stereotypical social constructs of gender role expectations and/or pain-related anxiety. One hundred fourteen university students (58 women) underwent two cycles of cold pressor pain test to measure pain threshold, tolerance, intensity, and unpleasantness. Participants also completed the Arabic GREP questionnaire and the Pain Anxiety Symptom Scale-Short form (PASS-20). It was found that Libyan men had higher pain thresholds and tolerances than women (mean difference, 95% CI: threshold = 4.69 (s), -0.72 to 10.1, p = 0.005; tolerance = 13.46 (s), 0.5-26.4, p = 0.018). There were significant differences between sexes in 6 out of 12 GREP items (p < 0.004 after Bonferonni adjustment). The results of mediational analysis showed that GREP factors were the mediators of the effects of sex on pain threshold (z = -2.452, p = 0.014 for Self Sensitivity); (z = -2.563, p = 0.01, for Self Endurance) and on pain tolerance (z = -2.538, p = 0.01 for Self Endurance). In conclusion, sex differences in response to pain were mediated by gender role expectations of pain but not pain-related anxiety.

Accuracy of the revised 2010 TNM classification in predicting the prognosis of patients treated for renal cell cancer in the north east of England.

BACKGROUND: The TNM classification for renal cell cancer (RCC) should accurately predict and assign prognostic information for patients. In this study the recent 2010 revision to the TNM classification was compared with the previous 2002 classification with regard to survival outcomes. METHODS: All patients having radical nephrectomy for RCC in the 5-year period 2004-8 at a tertiary referral centre were included. Pathological and radiological records were reviewed to identify TNM stage (2002 and 2010 classification) and survival data were captured. RESULTS: 345 patients with RCC were identified. Based on the 2002 TNM staging system and using outcomes in T1 staged tumours as a baseline, statistically significant differences in disease-specific survival were noted between patients with T1 and T3b tumours (log rank p<0.001) but not between those with T1 and T3a tumours (p=0.33). However, when tumour stage was reassigned according to the 2010 classification, patients with T3a tumours were also found to do statistically worse than T1 staged disease (p<0.001). CONCLUSION: In our cohort, the new 2010 TNM reclassification of T3 tumours showed better correlation with predicting worsening outcomes compared with localised disease.

Stellate ganglion blockade (SGB) for refractory index finger pain - a case report.

OBJECTIVE: To identify through case study the presentation and possible pathophysiological cause of complex regional pain syndrome and its preferential response to stellate ganglion blockade. SETTING: Complex regional pain syndrome can occur in an extremity after minor injury, fracture, surgery, peripheral nerve insult or spontaneously and is characterised by spontaneous pain, changes in skin temperature and colour, oedema, and motor disturbances. Pathophysiology is likely to involve peripheral and central components and neurological and inflammatory elements. There is no consistent approach to treatment with a wide variety of specialists involved. Diagnosis can be difficult, with over-diagnosis resulting from undue emphasis placed upon pain disproportionate to an inciting event despite the absence of other symptoms or under-diagnosed when subtle symptoms are not recognised. The International Association for the Study of Pain supports the use of sympathetic blocks to reduce sympathetic nervous system overactivity and relieve complex regional pain symptoms. Educational reviews promote stellate ganglion blockade as beneficial. Three blocks were given at 8, 10 and 13 months after the initial injury under local anaesthesia and sterile conditions. Physiotherapeutic input was delivered under block conditions to maximise joint and tissue mobility and facilitate restoration of function. CONCLUSION: This case demonstrates the need for practitioners from all disciplines to be able to identify the clinical characteristics of complex regional pain syndrome to instigate immediate treatment and supports the notion that stellate ganglion blockade is preferable to upper limb intravenous regional anaesthetic block for refractory index finger pain associated with complex regional pain syndrome.

The use of transcutaneous electrical nerve stimulation (TENS) to aid perceptual embodiment of prosthetic limbs.

Integration of prosthetic limb awareness into body schema is likely to aid manual control of the prosthesis. Physiotherapists and prosthetists use techniques to generate mechanical, visual and/or auditory feedback related to stimulation of the stump and proximal residual limb to improve prosthetic limb awareness. Electrical stimulation of afferent nerves using implanted electrodes can generate sensations of touch, joint movement, and position, in the missing, phantom limbs of amputees. We report here a novel hypothesis that non-invasive transcutaneous electrical nerve stimulation (TENS) could be used to facilitate the process of perceptual embodiment of a prosthesis into the body schema of amputees. Using a modified version of the rubber hand illusion (RHI), we have found that TENS paraesthesiae can be made to feel like it is emanating from a prosthetic hand in healthy participants with intact limbs. In addition, participants reported perceptual embodiment of the prosthetic hand into their body schema, i.e. it felt as if it is part of their body. We predict that projecting TENS paraesthesiae into the prosthetic limb(s) of amputees will provide sufficient sensory input to facilitate perceptual embodiment. This could prove to be a simple and inexpensive training aid to improve ambulation and prosthesis success.

An exercise programme for the management of lateral elbow tendinopathy.

BACKGROUND: Home exercise programmes and exercise programmes carried out in a clinical setting are commonly advocated for the treatment of lateral elbow tendinopathy (LET), a very common lesion of the arm with a well-defined clinical presentation. The aim of this study is to describe the use and effects of strengthening and stretching exercise programmes in the treatment of LET. ECCENTRIC EXERCISES: Slow progressive eccentric exercises for LET should be performed with the elbow in extension, forearm in pronation, and wrist in extended position (as high as possible). However, it is unclear how the injured tendon, which is loaded eccentrically, returns to the starting position without experiencing concentric loading and how the "slowness" of eccentric exercises should be defined. Nor has the treatment regimen of the eccentric exercises of a supervised exercise programme been defined. STRETCHING EXERCISES: Static stretching is defined as passively stretching a given muscle-tendon unit by slowly placing and maintaining it in a maximal position of stretch. We recommend the position should be held for 30-45 s, three times before and three times after eccentric exercises during each treatment session with a 30 s rest interval between each procedure. The treatment region of static stretching exercises when a supervised exercise programme is performed is unknown. DISCUSSION: A well designed trial is needed to study the effectiveness of a supervised exercise programme for LET consisting of eccentric and static stretching exercises. The issues relating to the supervised exercise programme should be defined so that therapists can replicate the programme.

Treatment of carpal tunnel syndrome with polarized polychromatic noncoherent light (Bioptron light): a preliminary, prospective, open clinical trial.

OBJECTIVE: Our aim was to assess the efficacy of polarized polychromatic noncoherent light (Bioptron light) in the treatment of idiopathic carpal tunnel syndrome. BACKGROUND: Carpal tunnel syndrome is the most common compression neuropathy, but no satisfactory conservative treatment is available at present. METHOD: An uncontrolled experimental study was conducted in patients who visited our clinic from mid-2001 to mid-2002. A total of 25 patients (22 women and three men) with unilateral idiopathic carpal tunnel syndrome, mild to moderate nocturnal pain, and paraesthesia lasting >3 months participated in the study. The average age of the patients was 47.4 years and the average duration of patients' symptoms was 5.2 months. Polarized polychromatic noncoherent light (Bioptron light) was administered perpendicular to the carpal tunnel area. The irradiation time for each session was 6 min at an operating distance of 5-10 cm from the carpal tunnel area, three times weekly for 4 weeks. Outcome measures used were the participants' global assessments of nocturnal pain and paraesthesia, respectively, at 4 weeks and 6 months. RESULTS: At 4 weeks, two patients (8%) had no change in nocturnal pain, six (24%) were in slightly less nocturnal pain, 12 (48%) were much better in regard to nocturnal pain and five (20%) were pain-free. At 6 months, three patients (12%) were slightly better in regard to nocturnal pain, 13 (52%) were much better regarding nocturnal pain, and nine patients (36%) were pain-free. At 4 weeks, four patients (16%) had no change in paraesthesia, five (20%) were slightly better, 13 patients (52%) were much better, and three patients (12%) were without paraesthesia. At 6 months, two patients (8%) had no change in paraesthesia, two (8%) were slightly better, 14 (56%) were much better, and seven (28%) were without paraesthesia. CONCLUSIONS: Nocturnal pain and paraesthesia associated with idiopathic carpal tunnel syndrome improved during polarized polychromatic noncoherent light (Bioptron light) treatment. Controlled clinical trials are needed to establish the absolute and relative effectiveness of this intervention.

Effectiveness of extracorporeal shock wave therapy for tennis elbow (lateral epicondylitis).

Randomised controlled trials were reviewed to evaluate the evidence of the effectiveness of extracorporeal shock wave therapy in the management of tennis elbow. Seven relevant trials were found, which had satisfactory methodology but conflicting results. Further research with well designed randomised control trials is needed to establish the absolute and relative effectiveness of this intervention for tennis elbow.

Cyriax physiotherapy for tennis elbow/lateral epicondylitis.

Tennis elbow or lateral epicondylitis is one of the most common lesions of the arm with a well defined clinical presentation, which significantly impacts on the community. Many treatment approaches have been proposed to manage this condition. One is Cyriax physiotherapy. The effectiveness and reported effects of this intervention are reviewed.

Peroxisome proliferator-activated receptor alpha is an androgen-responsive gene in human prostate and is highly expressed in prostatic adenocarcinoma.

Peroxisome proliferator-activated receptor (PPAR) alpha is a member of the nuclear receptor superfamily of ligand-activated transcription factors. PPARalpha is activated by peroxisome proliferators and fatty acids and has been shown to be involved in the transcriptional regulation of genes involved in fatty acid metabolism. In rodents, the PPARalpha-mediated change in such genes results in peroxisome proliferation and can lead to the induction of hepatocarcinogenesis. Using the mRNA differential display technique and Northern blot analysis, we have shown that chronic exposure of the prostate cancer epithelial cell line LNCaP to the synthetic androgen mibolerone results in the down-regulation of PPARalpha mRNA. Levels of PPARalpha mRNA are reduced to approximately 40% of control levels in LNCaP cells exposed to 10 nM mibolerone for 96 h. PPARalpha-responsive reporter plasmids derived from human ApoA-II and muscle carnitine palmitoyl-transferase I genes were stimulated by the PPARalpha-activating ligand Wy-14,643 in LNCaP cells. In situ hybridization and immunohistochemical analyses showed that PPARalpha expression in prostate is confined to epithelial cells. In benign prostatic tissue, PPARalpha mRNA was either absent or only weakly expressed in the basal epithelial cells. In 11 of 18 (61%) poorly differentiated (Gleason score, 8-10) prostatic carcinoma specimens, there was strong expression of PPARalpha compared with 4 of 12 Gleason score 7 tumors and 2 of 11 Gleason score 3-6 tumors (P < 0.01). These results suggest that PPARalpha is found and functional in human prostate and is down-regulated by androgens. The role of PPARalpha may be to integrate dietary fatty acid and steroid hormone signaling pathways, and its overexpression in advanced prostate cancer may indicate a role in tumor progression with the potential involvement of dietary factors.

Bone morphogenetic protein 6 in skeletal metastases from prostate cancer and other common human malignancies.

Prostatic adenocarcinoma commonly metastasizes to bone. Unlike most other bony secondaries, the majority of skeletal prostatic metastases are osteoblastic rather than osteolytic in nature. Several growth factors which are known to stimulate bone formation are expressed in benign and malignant prostate cells, but none has been specifically linked to osteosclerotic metastases. Bone morphogenetic proteins (BMPs) induce ectopic bone formation in vivo. We have reported previously that BMP-6 mRNA and protein are expressed in the majority of primary prostatic carcinomas with established skeletal metastases but rarely in clinically organ-confined tumours. This study examines the expression of BMP-6 mRNA in matched prostatic primary and secondary bony lesions and in isolated skeletal metastases from prostatic adenocarcinomas, as well as other common human malignancies, by in situ hybridization. BMP-6 mRNA was detected in 11 out of 13 bone metastases from prostate carcinoma and in three paired samples of primary prostate carcinoma and matching skeletal metastasis. Weak signals for BMP-6 were also present in 5 out of 17 skeletal deposits from non-prostatic malignancies. BMP-6 mRNA appears to be strongly expressed in prostatic adenocarcinomas, both in the primary tumour and in bone metastases. It is also expressed, though less frequently, in skeletal metastases from other human carcinomas. Our findings suggest that BMP-6 may hold potential as an attractive marker and possible mediator of skeletal metastases, particularly in prostate carcinoma.