Knee extensor strength is associated with pressure pain thresholds in adults with fibromyalgia

Five-year follow-up of the OptiTrain trial on concurrent resistance and high-intensity interval training during chemotherapy for patients with breast cancer

The protocol predefined aim of this study is to assess sustained effects of the OptiTrain trial on several health outcomes, 5 years after the baseline assessment. The OptiTrain study was a prospective, randomised controlled trial with 240 patients with breast cancer undergoing adjuvant chemotherapy that compared the effects of 16 weeks of two exercise programs, RT-HIIT and AT-HIIT, with usual care (UC). After a 5-year follow-up, eligible participants were evaluated for the primary outcome of cancer-related fatigue (CRF) and secondary outcomes including quality of life, symptoms, muscle strength, cardiorespiratory fitness, body mass, physical activity, and sedentary behavior. Statistical analysis was conducted using linear mixed models adjusted for baseline values. Tumour profile and menopausal status were additionally adjusted for CRF. Mean differences (MD), 95% confidence intervals (CIs), and standardized effect sizes (ES) were reported. At the 5-year follow-up, there were no statistically significant differences in total CRF between the intervention groups and the UC group. RT-HIIT reported significantly reduced pain sensitivity at the gluteus MD = 79.00 (95% CI 10.17, 147.83, ES = 0.55) compared to UC. Clinically meaningful differences for an increase in cognitive CRF and cardiorespiratory fitness were observed for the AT-HIIT versus UC group, and for lower limb strength for the RT-HIIT versus UC group, albeit without statistical significance. Engaging in targeted exercise during adjuvant chemotherapy for breast cancer provides short-term benefits in reducing fatigue and maintaining physical function. However, our 5-year follow-up indicates that these effects are limited in the long term. This underscores the need to support breast cancer survivors maintain their PA levels throughout their survivorship journey.

Test-Retest Reliability of Isokinetic Strength in Lower Limbs under Single and Dual Task Conditions in Women with Fibromyalgia

Background: Previous research has established good test-retest reliability for isokinetic dynamometry in fibromyalgia. However, the reliability of this test under dual-task conditions has not been investigated in fibromyalgia. Methods: A total of 10 women with fibromyalgia participated in this study. Participants completed the concentric/concentric test. The dual-task condition involved subtracting two by two while performing the test. Results: Reliability analysis under the single condition showed "poor" to "excellent" values for maximum peak torque in knee extension and "moderate" to "excellent" values for average. "Poor" to "excellent" reliability values were found in knee flexion for the maximum and average. Dual-task condition in knee extension ranged from "moderate" to "excellent" for maximum and average values, and in knee flexion, it ranged from "poor" to "excellent" for maximum value and from "moderate" to "excellent" for average value. Conclusions: Isokinetic dynamometry demonstrated sufficient reliability for measuring strength in knee extension maximum and average during single-task and dual-task conditions, along with knee flexion dual-task average in fibromyalgia. For knee flexion single-task maximum and average and knee flexion dual-task maximum, we did not obtain sufficiently reliable measurements. Only the concentric/concentric test has been studied, and future studies with a larger sample size are needed in order to generalize the results.

An Investigation of Medial Tibial Component Overhang in Unicompartmental and Total Knee Replacements Using Ultrasound in the Outpatient Department

Tibial component overhang is known to be a contributor to worse outcomes in knee arthroplasty. The aim of this study is to investigate the presence of tibial component overhang, and whether overhang correlates to a higher local tenderness in both medial unicompartmental and total knee replacements. Also, to determine if a rotational projection phenomenon is presented with radiographs when investigating tibial component overhang. A prospective study, including 64 participants, was performed, where ultrasound measurements were compared with postoperative radiographs. Local tenderness was measured as a pressure pain threshold, determined at 3 months postoperatively using algometry. Sixty-two of sixty-four patients had an underdiagnosed medial overhang on radiographs, with a mean difference of 2.4 mm between radiographs and ultrasound (p < 0.001), presenting a rotational projection phenomenon. When comparing sites with ultrasound measured overhang to sites without overhang measured by ultrasound, a higher local tenderness was observed (p < 0.001). A positive linear correlation was found between patients' overhang and local tenderness (r = 0.2; p = 0.045). Subgroup analysis of medial overhang showed significantly higher tenderness than all other locations. No significant differences were seen for lateral overhang. An apparent rotational projection phenomenon of overhang on radiographs was seen, and a linear association between overhang and local tenderness was demonstrated. This study warrants the use of ultrasound when a surgeon is presented with a patient with postoperative medial tenderness, but no overhang can be seen on radiographs. It should also raise awareness of implant selection and positioning during surgery, especially avoiding the overhang to be localized directly medially.

Isokinetic evaluation of the trunk muscle strength in housewives with fibromyalgia: a cross-sectional study

BACKGROUND

It is known that physical activity and muscular performance are reduced in fibromyalgia (FM) syndrome. This study aims to compare the performance of trunk muscles in women with FM and healthy controls and evaluate the correlation between trunk muscle strength and FM severity.

METHODS

Forty-six patients with FM and 42 age- and body mass index-matched healthy housewives without FM were included in the FM and control groups, respectively. The Fibromyalgia Impact Questionnaire (FIQ) was used for the assessment of FM severity. The pain intensity was evaluated using the visual analogical scale (VAS). An isokinetic dynamometer was used to measure the isokinetic trunk muscle strength. The peak torque (PT) values were recorded. The psychological status of the patients was evaluated using the Beck Depression Inventory.

RESULTS

There was no statistically significant difference in terms of age, BMI, and BDI scores in two groups (p > 0.05, for all). The isokinetic trunk extensor PT values were significantly lower in the FM group (p = 0.002 for 60°/s, and p < 0.001 for 90°/s and 120°/s) than control group. There was a statistically significant negative correlation between FIQ score and isokinetic extensor muscle parameters.

CONCLUSION

The results indicate that trunk extensor muscles were significantly weaker in FM patients. Trunk extensor muscle strength decreased as FM severity increased in FM patients.

Evidence-Based Optimal Cutoff Values with the Validation of Criterion-Referenced Standards for Sarcopenic Elderly Fitness Improvement

This study provides a newly updated perspective of information on severely screened 21 previous studies of the various measurement methods for improving physical fitness and providing determined cutoff values from our reserved elderly human database. We aimed to provide scientific evidence-based information regarding physical fitness standards for developing useful prognostics, promoting and maintaining health programs for sarcopenic elderly. 21 previous studies emphasizing criterion referenced standards and receiver operator characteristic (ROC) curve analyses for improving physical fitness were screened. For predicting the prevalence of sarcopenia, the t-test, logistic regression, linear regression, ROC curve analyses, and voluntary categorizations such as the twentieth or sixtieth percentile classification were used. Based on these scientific evidences, we determined cutoff values from our reserved DB and realized that 75 years for men and 70 years for women are the transitional period during which there are large declines in muscle and fat mass (p<0.01), which reflects physical function tests (p<0.01) in both genders. Using the six factors with ideal cutoff thresholds, an individual exercise program can be designed for alleviating symptoms of frailty caused by sarcopenia for the elderly.

Evidence-Based Optimal Cutoff Values with the Validation of Criterion-Referenced Standards for Sarcopenic Elderly Fitness Improvement

This study provides a newly updated perspective of information on severely screened 21 previous studies of the various measurement methods for improving physical fitness and providing determined cutoff values from our reserved elderly human database. We aimed to provide scientific evidence-based information regarding physical fitness standards for developing useful prognostics, promoting and maintaining health programs for sarcopenic elderly. 21 previous studies emphasizing criterion referenced standards and receiver operator characteristic (ROC) curve analyses for improving physical fitness were screened. For predicting the prevalence of sarcopenia, the t-test, logistic regression, linear regression, ROC curve analyses, and voluntary categorizations such as the twentieth or sixtieth percentile classification were used. Based on these scientific evidences, we determined cutoff values from our reserved DB and realized that 75 years for men and 70 years for women are the transitional period during which there are large declines in muscle and fat mass (p < 0.01), which reflects physical function tests (p < 0.01) in both genders. Using the six factors with ideal cutoff thresholds, an individual exercise program can be designed for alleviating symptoms of frailty caused by sarcopenia for the elderly.

Increased postural stiffness during challenging postural tasks in patients with knee osteoarthritis with high pain sensitization

BACKGROUND

Postural stability is affected in knee osteoarthritis patients who present with pain but the link to pain sensitization is unclear.

METHODS

Patients with knee osteoarthritis completed the Knee Injury and Osteoarthritis Outcome Score and pressure pain thresholds were assessed bilaterally at the knee, lower leg and forearm prior to standing quietly (1 min) on a force platform in four conditions: Firm surface with open eyes, firm surface with closed eyes, soft surface with open eyes, and soft surface with closed eyes. Pain intensity during standing was assessed via numerical rating scale. Postural stability was assessed by the range, velocity, and standard deviation of the Center of Pressure (CoP) extracted from the force platform. The means of three repeated measures per standing condition were analysed. High-sensitization and low-sensitization groups were defined based on bilateral pressure pain thresholds from leg and arm.

FINDINGS

Fifty-six patients were included. Compared with the low-sensitization group, the high-sensitization group demonstrated 1) smaller pressure pain thresholds at the knee (P < 0.05) although the Knee Injury and Osteoarthritis Outcome Score and pain intensity were not significantly different between groups, and 2) smaller range of the CoP in the anterior-posterior direction during the soft surface with closed eyes condition (P < 0.05).

INTERPRETATION

Smaller CoP range suggest that patients with more widespread pain sensitivity have increased postural stiffness compared with the low-sensitization group. The greater stiffness found in high-sensitization patients under sensory restrictions (closed eyes and reduced proprioception) might relate to restricted integration of sensory information due to widespread pain sensitization.

Generalized Hyperalgesia in Children and Adults Diagnosed With Hypermobility Syndrome and Ehlers-Danlos Syndrome Hypermobility Type: A Discriminative Analysis

OBJECTIVE

Lowered pressure-pain thresholds have been demonstrated in adults with Ehlers-Danlos syndrome hypermobility type (EDS-HT), but whether these findings are also present in children is unclear. Therefore, the objectives of the study were to determine whether generalized hyperalgesia is present in children with hypermobility syndrome (HMS)/EDS-HT, explore potential differences in pressure-pain thresholds between children and adults with HMS/EDS-HT, and determine the discriminative value of generalized hyperalgesia.

METHODS

Patients were classified in 1 of 3 groups: HMS/EDS-HT, hypermobile (Beighton score ≥4 of 9), and healthy controls. Descriptive data of age, sex, body mass index, Beighton score, skin laxity, and medication usage were collected. Generalized hyperalgesia was quantified by the average pressure-pain thresholds collected from 12 locations. Confounders collected were pain locations/intensity, fatigue, and psychological distress. Comparisons between children with HMS/EDS-HT and normative values, between children and adults with HMS/EDS-HT, and corrected confounders were analyzed with multivariate analysis of covariance. The discriminative value of generalized hyperalgesia employed to differentiate between HMS/EDS-HT, hypermobility, and controls was quantified with logistic regression.

RESULTS

Significantly lower pressure-pain thresholds were found in children with HMS/EDS-HT compared to normative values (range -22.0% to -59.0%; P ≤ 0.05). When applying a threshold of 30.8 N/cm² for males and 29.0 N/cm² for females, the presence of generalized hyperalgesia discriminated between individuals with HMS/EDS-HT, hypermobility, and healthy controls (odds ratio 6.0).

CONCLUSION

Children and adults with HMS/EDS-HT are characterized by hypermobility, chronic pain, and generalized hyperalgesia. The presence of generalized hyperalgesia may indicate involvement of the central nervous system in the development of chronic pain.

Comparative assessment of knee extensor and flexor muscle strength measured using a hand-held vs. isokinetic dynamometer

[Purpose] To compare measurements of knee extensor and flexor muscle strength performed using a hand-held dynamometer and an isokinetic dynamometer in apparently healthy subjects. [Subjects and Methods] Thirty adult volunteers underwent knee muscle strength evaluation using an isokinetic or a hand-held dynamometer. [Results] Strong positive correlations were found between the 2 methods, with correlation coefficients r ranging from 0.72 (95% confidence interval [CI], 0.48-0.86) to 0.87 (95% CI, 0.75-0.94), depending on the muscle group and the isokinetic evaluation mode. The reproducibility of the hand-held dynamometer findings was good, judged by a coefficient of variation of 3.2-4.2%. However, the correlation between the 2 methods for the assessment of flexor/extensor ratios ranged from -0.04 to 0.46. [Conclusion] Knee extensor and flexor muscle strength recorded with a hand-held dynamometer is reproducible and significantly correlated with the isokinetic values, indicating that this method may in some cases be a useful replacement for isokinetic strength measurement. However, for strength ratio assessment, and when judged against the isokinetic standard, a hand-held dynamometer is not a valid option.

Chronic Pain and Mental Health Disorders: Shared Neural Mechanisms, Epidemiology, and Treatment

Chronic pain and mental health disorders are common in the general population, and epidemiological studies suggest that a bidirectional relationship exists between these 2 conditions. The observations from functional imaging studies suggest that this bidirectional relationship is due in part to shared neural mechanisms. In addition to depression, anxiety, and substance use disorders, individuals with chronic pain are at risk of other mental health problems including suicide and cigarette smoking and many have sustained sexual violence. Within the broader biopsychosocial model of pain, the fear-avoidance model explains how behavioral factors affect the temporal course of chronic pain and provides the framework for an array of efficacious behavioral interventions including cognitive-behavioral therapy, acceptance-based therapies, and multidisciplinary pain rehabilitation. Concomitant pain and mental health disorders often complicate pharmacological management, but several drug classes, including serotonin-norepinephrine reuptake inhibitors, tricyclic antidepressants, and anticonvulsants, have efficacy for both conditions and should be considered first-line treatment agents.

Tolerance of exercise-induced pain at a fixed rating of perceived exertion predicts time trial cycling performance

To compare the predictive capacity of experimental pain and exercised-induced pain (EIP) on exercise performance. Thirty-two recreationally active male (n = 23) and female (n = 9) participants were recruited. Participants completed measures of pain tolerance by cold pressor test (CPT), pain pressure threshold via algometry (PPT), and EIP tolerance using an RPE clamp trial. A VO_2max test provided traditional predictors of performance [VO_2max , gas-exchange threshold‎ (GET), peak power output (PPO)]. Finally, participants completed a 16.1-km cycling time trial (TT). No correlation was found between experimental pain measures (CPT, PPT) and TT performance. However, there was a significant correlation between EIP tolerance and TT performance (R = -0.83, P < 0.01). Regression analysis for pain and physiological predictor variables (mean pain in CPT, PPT, EIP tolerance, VO_2max , PPO, GET) revealed that a significant model (P < 0.01) emerged when only PPO (Adjusted R²  = 0.739) and EIP tolerance (ΔR²  = 0.075) were used to predict TT performance. These findings suggest that EIP tolerance is an important factor in endurance performance. However, PPT and CPT have limited ability to assess this relationship, and so their use in EIP research should be treated with caution.

Measuring mechanical pain: the refinement and standardization of pressure pain threshold measurements

Pain thresholds are widely used in behavioral research, but unlike other pain modalities, a standardized assessment of pressure pain remains a challenge. In this research, we describe the application of an automatic pressure algometer with a linear increase in force. Ergonomically designed fixation devices were developed to increase the accuracy and to shorten the time of each measurement. Ten healthy volunteers were included in a pilot study to test the algometry method. Pressure pain thresholds (PPTs) were investigated over 2 experimental days in three nonconsecutive runs at 29 measurement sites. During the experiment, subjects reported their subjective sleepiness, level of state-anxiety, psychological status and the perceived pain intensity of each measurement. Pain intensity ratings indicate that instructions were followed. State-anxiety and subjective sleepiness levels were low throughout the experiment. The method has proven to be suitable for standardized PPT measurements across the body in an ergonomic, safe, and user-friendly fashion.

Association of cardiorespiratory fitness with pressure pain sensitivity and clinical pain in women with fibromyalgia

The aim of the present study was to assess the association of cardiorespiratory fitness (CRF) with pressure pain sensitivity and clinical pain in women with fibromyalgia (FM). Thirty-one women with FM were included in the study. Pressure pain sensitivity was assessed with an electronic pressure dolorimeter. The average pressure pain threshold (PPT) from the 18 FM-related tender points and the tender points count (TPC) were recorded. Clinical pain was assessed on a 10-cm visual analog scale (VAS; from the FM impact questionnaire). The patients performed an incremental treadmill test, which consisted in six increasing workloads. Gas exchange was continuously monitored, and peak oxygen uptake (as measure of CRF) was recorded. Pairwise correlation and multiple linear regression were used to examine the association of CRF with PPT and VAS, and binary logistic regression assessed the odds of having <18 positive tender points as a function of CRF. The correlations of CRF with the average PPT and VAS were 0.355, (P < 0.001) and 0.058 (P > 0.05), respectively. Regression analyses revealed that CRF was associated with the PPT (B = 0.093; 95 % CI 0.064-0.122; P < 0.001; R (2) = 0.306) and TPC (OR 1.51; 95 % CI 1.30-1.75; P < 0.001) but not with VAS (B = 0.068; 95 % CI -0.061-0.197; P > 0.05). The findings of this study suggest that CRF is associated with pressure pain sensitivity but not with clinical pain in women with FM. Further longitudinal and intervention studies are needed to determine whether CRF could be involved in some mechanisms of pain processing.

Pain severity is associated with muscle strength and peak oxygen uptake in adults with fibromyalgia

Background

The associations between pain, lower extremity strength, and aerobic conditioning have not been widely investigated in adults with fibromyalgia (FM). The principle objective of this study was to investigate the relationship between pain severity and knee strength in patients seeking treatment for FM. A secondary objective was to investigate the relationship between pain scores and aerobic conditioning.

Methods

Three measures of knee strength (isokinetic extensor, isokinetic flexor, isometric extensor) were quantified in the dominant leg of 69 adults with FM using a dynamometer at speeds of 60 degrees per second (60°/s) and 180°/s. Peak oxygen uptake (VO₂) was assessed using a cycle ergometer, and pain was assessed using the pain severity subscale of the Multidimensional Pain Inventory.

Results

In univariable linear regression analyses using pain severity as the dependent variable, lesser values of isokinetic knee extensor strength at 60°/s (P=0.041) and 180°/s (P=0.010), isokinetic knee flexor strength at 60°/s (P=0.028) and 180°/s (P=0.003), and peak VO₂ uptake (P=0.031) were predictive of greater pain severity scores. In multiple variable linear regression models adjusted for age, sex, body mass index, and opioid use, the following associations retained statistical significance; isokinetic knee extensor strength at 60°/s (P=0.020) and 180°/s (P=0.003), isokinetic knee flexor strength at 60°/s (P=0.015) and 180°/s (P=0.001), and peak VO₂ uptake (P=0.014). However, no significant associations were found between pain severity and isometric knee extensor strength.

Conclusion

The main findings from this study were that lesser values of isokinetic knee strength and peak VO₂ uptake were predictive of greater pain severity scores. These results build on the findings of previous investigations, but ongoing research is needed to further characterize the effects of strength and peak VO₂ uptake on the pathophysiology of FM.

Chronic pain in patients with the hypermobility type of Ehlers-Danlos syndrome: evidence for generalized hyperalgesia

Chronic widespread pain is highly present in patients with the Ehlers-Danlos syndrome hypermobility type (EDS-HT), but up to now, evidence for generalized hyperalgesia is lacking. The aim of this study is to investigate whether pressure pain thresholds (PPTs) at both symptomatic and asymptomatic body areas differ in EDS-HT patients compared to healthy subjects. Twenty-three women with EDS-HT and 23 gender- and age-matched healthy controls participated. All subjects marked on Margolis Pain Diagram where they felt pain lasting longer than 24 h in the past 4 weeks. Then, they completed several questionnaires assessing pain cognitions, fatigue, disability, and general health status, in order to take the possible influence of these factors on PPTs into account. Patients also completed a form concerning the type of pain they experienced. Thereupon, a blinded researcher assessed PPTs at 14 body locations on the trunk and extremities. PPTs were compared for the two complete groups. In addition, PPTs of patients and controls who did not report pain in a respective zone were compared. PPTs of the patients were significantly lower compared to those of the control group, also when pain-free samples per zone were compared. The mean (SD) PPT was 2.9 (1.62) kg/cm(2) in the EDS-HT patients and 5.2 (1.88) kg/cm(2) in the controls (P < 0.001). No confounding factors responsible for the observed differences could be revealed. In half of the patient group, a predominantly neuropathic pain component was likely present. This study provides evidence for the existence of hyperalgesia even in asymptomatic areas (generalized secondary hyperalgesia). The generalized hyperalgesia may represent the involvement of a sensitized central nervous system, which inquires an adapted pain management for this patient group.