Sensory profiles and their role in the persistence of central sensitization symptoms in low back pain. A prospective cohort study.

INTRODUCTION: Acute lower back pain can lead to neuroplastic changes in the central nervous system, and symptoms of central sensitization after 12 weeks. While sensory sensitivity has been shown to predict symptoms of central sensitization, trait sensory profiles may be prognostic in the persistence of central sensitization symptoms in low back pain over time. OBJECTIVE: To examine sensory profiles as prognostic symptoms of central sensitization in people with acute low back pain. METHODS: A longitudinal type 2 prognostic factor research study was performed according to the PROGRESS framework. Baseline and 12-week follow-up measures were taken using the Adolescent/Adult Sensory Profile and the Central Sensitization Inventory measures. Study participants were consecutively included from primary care physiotherapy practices. Univariable, and multivariable regression analyses were performed to adjust sensory profiles based on previous history of low back pain, baseline Central Sensitization Inventory scores, level of pain, disability, age, and duration of low back pain. RESULTS: After adjustment, the sensory profiles of Low Registration B = 0.44, 95%CI (0.18, 0.70), Sensation Seeking B = 0.38, 95%CI (0.19, 0.57), Sensory Sensitive B = 0.49, 95%CI (0.25, 0.74), Sensation Avoiding B = 0.40, 95% CI (0.15, 0.65) was significantly associated with the persistence of central sensitization symptoms (N = 103). CONCLUSION: Sensory profiles may predict symptoms of central sensitization after 12 weeks in people with acute low back pain.

Skeletal Muscle Echo Intensity Values Differ Significantly across Ultrasound Parameter Settings.

Echo intensity determined by muscle ultrasound has been proposed as an efficient method for the assessment of muscle quality. The influence of changing ultrasound parameter settings on echo intensity values was assessed using a standardized approach. In this repeated measures cross-sectional study, sixteen repeated scans of rectus femoris, gracilis, and rectus abdominis were taken in 21 middle-aged persons with a portable Mindray M7 premium ultrasound machine equipped with a linear 5.0-10.0 MHz transducer. The settings of three parameters were fixed: gain, depth, and frequency. The settings of the following adjustable parameters were changed over their entire range: dynamic range, gray map, line density, persistence, and IClear. Repeated measures analyses were performed to evaluate the effect of changing the settings on echo intensity values. In all three muscles, dynamic range, gray map, and IClear correlated significantly (rrm-values ranging between -0.86 and 0.45) with echo intensity. In all three muscles, the echo intensity values differed significantly across the dynamic range (p < 0.013), gray map (p < 0.003), and IClear (p < 0.003). In middle-aged subjects, echo intensity values of lower limb and trunk muscles are significantly related to ultrasound parameters and significantly differ across their respective setting range. For the assessment of muscle quality through ultrasound, it is suggested to fix parameter settings within their midrange in order to minimize the effect of setting-dependent factors on EI values.

Exploring reliable photogrammetry techniques for 3D modeling in anatomical research and education.

In anatomical research and education, three-dimensional visualization of anatomical structures is crucial for understanding spatial relationships in diagnostics, surgical planning, and teaching. While computed tomography (CT) and magnetic resonance imaging (MRI) offer valuable insights, they are often expensive and require specialized resources. This study explores photogrammetry as an affordable and accessible approach for 3D modeling in anatomical contexts. Two photogrammetry methods were compared: conventional open-source software (Colmap) and Apple's RealityKit Object Capture. Human C3 vertebrae were imaged with a 24 MP camera, with and without a cross-polarization filter. Reconstruction times, vertex distances, surface area, and volume measurements were compared to CT scans. Results revealed that the Object Capture method surpassed the conventional approach in reconstruction speed and user-friendliness. Both methods exhibited similar vertex distance from reference mesh and volume measurements, although the conventional approach produced larger surface areas compared to CT-based models. Cross-polarization filters eliminated the need for pre-processing and improved outcomes in challenging lighting conditions. This study demonstrates that photogrammetry, especially Object Capture, as a reliable and time-efficient tool for 3D modeling in anatomical research and education. It offers accessible alternatives to traditional techniques with advantages in texture mapping. While further validation of various anatomical structures is required, the accessibility and cost-effectiveness of photogrammetry make it a valuable asset for the field. In summary, photogrammetry would have the potential to revolutionize anatomical research and education by providing cost-effective, accessible, and accurate 3D modeling. The study underscores the promise of advancing anatomical research and education through the integration of photogrammetry with ongoing improvements in user-friendliness and accessibility.

Impact of COVID-19 on Physical Activity, Fatigue, and Frailty in Community-Dwelling Older Adults: A Cross-Sectional Study.

This study aimed to describe the level of physical activity and its relation to fatigue and frailty during the COVID-19 pandemic in community-dwelling older adults aged 80 years and over. Three hundred and ninety-one older adults (aged 86.5 ± 3.00) completed a survey including physical activity, the Mobility Tiredness scale, and the FRAIL scale. Linear regression analysis was conducted to assess whether the variables age, sex, and physical activity (independent factors) were significantly related to fatigue and frailty. Respectively, 30.5% and 24.7% of the participants reported a decrease in walking and in energy-intensive activities; 25.4% reported increased sedentary behavior. A lower level of physical activity was associated with higher levels of fatigue and increased frailty risk (p < .05), independently from psychological symptoms. These results are important because participants with lower levels of physical activity and more sedentary behavior are more likely to feel fatigued and have higher risk to be frail.

Upper limb nerve variations may alter clinical diagnosis: a scoping review / Las variaciones nerviosas del miembros superior pueden alterar el diagnóstico clínico: una revisión de alcance

SUMMARY: Upper limb nerve variations may be related to the absence of a nerve, an interconnection between two nerves or a variant course. The purpose of this review is to screen the existing literature on upper limb nerve variations that may alter the neurologic diagnostic process. A scoping review was performed following PRISMA for Scoping Reviews guidelines. Initially, 1331 articles were identified by searching Pubmed and Web of Science until the 22nd of October 2022. After screening, reading, and additional searching 50 articles were included in this review. Variations were divided into two categories: 1) variations causing a different innervation pattern involving sensory, motor, or both types of fibers, and 2) variations causing or related to compression syndromes. Two-thirds of the included articles were cadaver studies. Nine articles were diagnostic studies on symptomatic or healthy individuals involving medical imaging and/or surgery. Nerve variations that may cause a different innervation pattern concern most frequently their interconnection. The connection between the median and musculocutaneous nerve in the upper limb and the connection between the median and ulnar nerve in the forearm (Martin-Gruber) or hand (Riche-Cannieu) may be present in half of the population. Injury to these connections may cause compound peripheral neuropathies a result of variant sensory and motor branching patterns. Muscular, vascular, or combined anomalies in the forearm were reported as causes of entrapment neuropathies. These nerve variations may mimic classical entrapment syndromes such as carpal tunnel syndrome or compression at ulnar canal (Guyon's canal). Knowledge of frequent nerve variations in the arm may be important during the diagnostic process and examination. Variant innervation patterns may explain non-classical clinical signs and/or symptoms during provocative tests. Classical nerve compression syndromes in the arm may warrant for differential diagnosis, especially in the case of persistent or recurrent symptoms.

Las variaciones nerviosas del miembro superior pueden estar relacionadas con la ausencia de un nervio, una interconexión entre dos nervios o un curso variante. El objetivo de esta revisión fue examinar la literatura existente sobre las variaciones de los nervios de los miembros superiores que pueden alterar el proceso de diagnóstico neurológico. Se realizó una revisión de alcance siguiendo las pautas de PRISMA para revisiones de alcance. Inicialmente, se identificaron 1331 artículos mediante la búsqueda en Pubmed y Web of Science hasta el 22 de octubre de 2022. Después de la selección, la lectura y la búsqueda adicional, se incluyeron 50 artículos en esta revisión. Las variaciones se dividieron en dos categorías: 1) variaciones que causan un patrón de inervación diferente que involucra fibras sensoriales, motoras o de ambos tipos, y 2) variaciones que causan o están relacionadas con síndromes de compresión. Dos tercios de los artículos incluidos eran estudios de cadáveres. Nueve artículos fueron estudios de diagnóstico en individuos sintomáticos o sanos que involucraron imágenes médicas y/o cirugía. Las variaciones nerviosas que pueden causar un patrón de inervación diferente se refieren con mayor frecuencia a su interconexión. La conexión entre el nervio mediano y musculocutáneo en el miembro superior y la conexión entre el nervio mediano y ulnar en el antebrazo (Martin-Gruber) o la mano (Riche-Cannieu) puede estar presente en la mitad de la población. La lesión de estas conexiones puede causar neuropatías periféricas compuestas como resultado de patrones de ramificación variantes sensitivos y motores. Se informaron anomalías musculares, vasculares o combinadas en el antebrazo como causas de neuropatías por atrapamiento. Estas variaciones nerviosas pueden imitar los síndromes de atrapamiento clásicos, como el síndrome del túnel carpiano o la compresión en el canal ulnar. El conocimiento de las variaciones nerviosas frecuentes en el brazo puede ser importante durante el proceso de diagnóstico y examen. Los patrones de inervación variantes pueden explicar los signos y/o síntomas clínicos no clásicos durante las pruebas de provocación. Los síndromes clásicos de compresión nerviosa en el brazo pueden justificar el diagnóstico diferencial, especialmente en el caso de síntomas persistentes o recurrentes.

The correlation of muscle quantity and quality between all vertebra levels and level L3, measured with CT: An exploratory study.

Introduction: In patients with cancer, low muscle mass has been associated with a higher risk of fatigue, poorer treatment outcomes, and mortality. To determine body composition with computed tomography (CT), measuring the muscle quantity at the level of lumbar 3 (L3) is suggested. However, in patients with cancer, CT imaging of the L3 level is not always available. Thus far, little is known about the extent to which other vertebra levels could be useful for measuring muscle status. In this study, we aimed to assess the correlation of the muscle quantity and quality between any vertebra level and L3 level in patients with various tumor localizations. Methods: Two hundred-twenty Positron Emission Tomography (PET)-CT images of patients with four different tumor localizations were included: 1. head and neck (n = 34), 2. esophagus (n = 45), 3. lung (n = 54), and 4. melanoma (n = 87). From the whole body scan, 24 slices were used, i.e., one for each vertebra level. Two examiners contoured the muscles independently. After contouring, muscle quantity was estimated by calculating skeletal muscle area (SMA) and skeletal muscle index (SMI). Muscle quality was assessed by calculating muscle radiation attenuation (MRA). Pearson correlation coefficient was used to determine whether the other vertebra levels correlate with L3 level. Results: For SMA, strong correlations were found between C1-C3 and L3, and C7-L5 and L3 (r = 0.72-0.95). For SMI, strong correlations were found between the levels C1-C2, C7-T5, T7-L5, and L3 (r = 0.70-0.93), respectively. For MRA, strong correlations were found between T1-L5 and L3 (r = 0.71-0.95). Discussion: For muscle quantity, the correlations between the cervical, thoracic, and lumbar levels are good, except for the cervical levels in patients with esophageal cancer. For muscle quality, the correlations between the other levels and L3 are good, except for the cervical levels in patients with melanoma. If visualization of L3 on the CT scan is absent, the other thoracic and lumbar vertebra levels could serve as a proxy to measure muscle quantity and quality in patients with head and neck, esophageal, lung cancer, and melanoma, whereas the cervical levels may be less reliable as a proxy in some patient groups.

Reliability of Muscle Quantity and Quality Measured With Extended-Field-of-View Ultrasound at Nine Body Sites.

OBJECTIVE: Measuring muscle quantity and quality is very important because the loss of muscle quantity and quality is associated with several adverse effects specifically in older people. Ultrasound is a method widely used to measure muscle quantity and quality. One problem with ultrasound is its limited field of view, which makes it impossible to measure the muscle quantity and quality of certain muscles. In this study, we aimed to evaluate the intra- and inter-rater reliability of extended-field-of-view (EFOV) ultrasound for the measurement of muscle quantity and quality in nine muscles of the limbs and trunk. METHODS: Two examiners took two ultrasound EFOV images with a linear probe from each of the muscle sites. The intraclass correlation coefficient (ICC) was used, and the standard error of measurement and coefficient of variation were calculated. RESULTS: Intra-rater reliability was good to excellent (ICC = 0.2-1.00) for all muscle measurements. The inter-rater reliability for most of the muscle measurements was good to excellent (ICC = 0.82-0.98). Inter-rater reliability was moderate (0.58-0.72) for some muscle quantity measurements of the tibialis anterior, gastrocnemius, rectus femoris, biceps femoris and triceps brachii muscles. CONCLUSION: Muscle quantity and quality can be measured reliably using EFOV US.

Functioning of People with Lipoedema According to All Domains of the International Classification of Functioning, Disability and Health: A Scoping Review.

Lipoedema is a painful non-pitting diffuse "fatty" swelling, usually confined to the legs, that occurs mainly in women. This scoping review aimed to provide an overview of the available research on the functioning of people with lipoedema, according to the International Classification of Functioning, Disability and Health (ICF) framework. Relevant publications and gray literature were retrieved until October 2022. The results sections of each publication were organized using a thematic framework approach. All included studies reported at least one outcome fitting within the domains of body functions and body structures, with most studies focusing on the categories of "sensation of pain", "immunological system functions", and "weight maintenance functions". The ICF domains of activities and participation and environmental factors were mentioned in a small number of the included studies (17 and 13%, respectively), while the domain of personal factors was studied in half of the included studies. In conclusion, the emphasis of lipoedema research is on its description from a disorder-oriented point of view in the form of body functions and body structures, with a lack of information about the other domains of functioning.

Muscle Endurance and Self-Perceived Fatigue Predict Decline in Gait Speed and Activities of Daily Living After 1-Year Follow-Up: Results From the BUTTERFLY Study.

BACKGROUND: Fatigue might influence the losses in activities of daily living (ADL). When fatigue parameters are present before the experience of losses in ADL and gait speed, they can be used as early warning signals. This study aimed to explore the predictive value of muscle endurance and fatigue on changes in ADL and gait speed in community-dwelling older adults aged 80 and older. METHODS: Three hundred twenty four community-dwelling older adults aged 80 and older of the BUTTERFLY study were assessed after 1 year for muscle endurance, self-perceived fatigue, ADL, and gait speed. Exploratory factor analysis (EFA) was performed to explore, whether there is an underlying arrangement of the fatigue parameters. Mediating logistic regression analyses were used to investigate whether muscle endurance mediated by self-perceived fatigue predicts the decline in gait speed and ADL after 1-year follow-up. RESULTS: EFA indicated a 2-factor model (muscle endurance factor and self-perceived fatigue factor) and had a moderate fit (X2: 374.81, df: 2, comparative fit index; 0.710, Tucker-Lewis index (TLI): 0.961, root mean square error of approximation [90%]: 0.048 [0.00-0.90]). Muscle endurance mediated by self-perceived fatigue had an indirect effect on the prediction of decline in Basal-ADL (-0.27), Instrumental-ADL (-0.25), and gait speed (-0.28) after 1-year follow-up. CONCLUSION: This study showed that low muscle endurance combined with high self-perceived fatigue can predict changes in ADL after 1-year follow-up. These parameters might be very suitable for use in evaluating intrinsic capacity and can help to reduce the limitations in clinical usage of the vitality domain in the framework of intrinsic capacity.

The Temporal Modulation of Nocebo Hyperalgesia in a Model of Sustained Pain.

Background: The direction and the magnitude of verbal suggestions have been shown to be strong modulators of nocebo hyperalgesia, while little attention has been given to the role of their temporal content. Here, we investigate whether temporal suggestions modulate the timing of nocebo hyperalgesia in an experimental model of sustained pain. Methods: Fifty-one healthy participants were allocated to one of three groups. Participants received an inert cream and were instructed that the agent had either hyperalgesic properties setting in after 5 (Nocebo 5, N5) or 30 (Nocebo 30, N30) minutes from cream application, or hydrating properties (No Expectation Group, NE). Pain was induced by the Cold Pressure Test (CPT) which was repeated before cream application (baseline) and after 10 (Test10) and 35 (Test35) minutes. Changes in pain tolerance and in HR at each test point in respect to baseline were compared between the three groups. Results: Tolerance change at Test 10 (Δ10) was greater in N5 (MED = -36.8; IQR = 20.9) compared to NE (MED = -5.3; IQR = 22.4; p < 0.001) and N30 (MED = 0.0; IQR = 23.1; p < 0.001), showing that hyperalgesia was only present in the group that expected the effect of the cream to set in early. Tolerance change at Test 35 (Δ35) was greater in N5 (MED = -36.3; IQR = 35.3; p = 0.002) and in N30 (MED = -33.3; IQR = 34.8; p = 0.009) compared to NE, indicating delayed onset of hyperalgesia in N30, and sustained hyperalgesia in N5. No group differences were found for HR. Conclusions: Our study demonstrated that temporal expectations shift nocebo response onset in a model of sustained pain.

Non-linear Associations Between Visceral Adipose Tissue Distribution and Anthropometry-Based Estimates of Visceral Adiposity.

Background: Recent evidence suggests that excess visceral adipose tissue (VAT) is associated with future loss of subcutaneous adipose tissue (SAT) and skeletal muscle (SM) with aging. In clinical settings (abdominal) circumferences are commonly used to estimate body composition (BC). We aimed to study the linearity of VAT distribution ratios (i.e., VAT/SAT ratio and VAT/SM ratio), waist-to-hip ratio (WHR) and waist circumference (WC) with age and the relationship of VAT distribution ratios with anthropometry (i.e., WHR and WC). Materials and Methods: BC was determined using whole body magnetic resonance imaging in a large multi-ethnic group of 419 adults (42% white, 30% black, 15% Hispanic, 13% Asian, 1% other) with a BMI ranging from 15.9 to 40.8kg/m2. Linear and non-linear regression analysis was used to examine the linearity of VAT distribution ratios and anthropometry from 18 to 88 years. The relation between VAT distribution ratios and anthropometry was assessed separately. Results: In both sexes non-linear relationships were found between BC estimates and age, and between BC measures mutually. The ratios of VAT/SAT and VAT/SM showed quadratic relationships with age. VAT distribution ratios showed exponential or quadratic relationships with anthropometry with coefficients of determination ranging between 18 and 55%. Conclusion: In both sexes, VAT distribution ratios showed curvilinear relationships with age and with anthropometry. Given the sex differences in VAT distribution ratios, WHR and WC represent different BC proportions in men and women. These results emphasize the challenge when interpreting changes in BC based upon linear extrapolations in clinical practice.

The validity of ultrasound-derived equation models to predict whole-body muscle mass: A systematic review.

BACKGROUND & AIMS: Sarcopenia is defined as the age-related loss in muscle quantity and quality which is associated with physical disability. The assessment of muscle quantity plays a role in the diagnosis of sarcopenia. However, the methods used for this assessment have many disadvantages in daily practice and research, like high costs, exposure to radiation, not being portable, or doubtful reliability. Ultrasound has been suggested for the estimation of muscle quantity by estimating muscle mass, using a prediction equation based on muscle thickness. In this systematic review, we aimed to summarize the available evidence on existing prediction equations to estimate muscle mass and to assess whether these are applicable in various adult populations. METHODS: The databases PubMed, PsycINFO, and Web of Science were used to search for studies predicting total or appendicular muscle mass using ultrasound. The methodological quality of the included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies, version 2 (QUADAS-2) and the quality assessment checklist (QA) designed by Pretorius and Keating (2008). RESULTS: Twelve studies were included in this systematic review. The participants were between 18 and 79 years old. Magnetic Resonance Imaging and dual-energy X-ray absorptiometry were used as reference methods. The studies generally had low risk of bias and there were low concerns regarding the applicability (QUADAS-2). Nine out of eleven studies reached high quality on the QA. All equations were developed in healthy adults. CONCLUSIONS: The ultrasound-derived equations in the included articles are valid and applicable in a healthy population. For a Caucasian population we recommend to use the equation of Abe et al., 2015. While for an Asian population, we recommend to use the equation of Abe et al., 2018, for the South American population, the use of the equation of Barbosa-Silva et al., 2021 is the most appropriate.

MR of tendons about the hip: A study in asymptomatic volunteers.

PURPOSE: Tendon pathology around the hip is a common entity. The aim of this study was to detect tendon abnormalities around the hip in a population of asymptomatic volunteers. MATERIALS AND METHODS: Fifty volunteers (100 hips) referred for non-musculoskeletal conditions were evaluated with an additional coronal STIR-weighted MRI imaging on a 1.5 MR unit. This group was composed of 27 women and 23 men with a mean age of 52 (19-91 years). The images were interpreted independently by 2 musculoskeletal radiologists. All tendons around the hip were given a score from 0 to 4, with a score 0 corresponding to no abnormality, score 1 to signal alteration around the tendon, score 2 to minimal signal abnormality in the tendon, score 3 partial tear and score 4 complete rupture. The trochanteric bursa was also evaluated and its size was measured. It was also given a score from 0 to 3 (0: no abnormality, 1: slight hypersignal, 2: bursitis < 10 mm, 3: bursitis ≥ 10 mm). RESULTS: High intratendinous signal was commonly found at the joined insertion of biceps femoris and semitendinosus (18% L, 20% R), the semimembranosus (24% L, 20% R), gluteus minimus (6% L, 11% R) and rectus femoris (9% L, 3% R). A small trochanteric bursa was seen in 33% of the volunteers on the left side and 32% on the right side. The interobserver correlation was very good with an intraclass correlation coefficient of 0.79 (CI: 0.74-0.85). CONCLUSION: Slight signal alterations might be found in the insertions of the rectus femoris, hamstrings and gluteus minimus tendons. A small to moderate trochanteric bursitis might also be seen. This suggests that care should be taken when interpreting MR scans to attribute symptoms to these findings.

Electrochemical Skin Conductance Alterations during Spinal Cord Stimulation: An Experimental Study.

Despite the well-known clinical effects of spinal cord stimulation (SCS), the mechanisms of action have not yet been fully unraveled. The primary aim of this study was to measure whether electrochemical skin conductance, as a measure of peripheral sympathetic autonomic function, is altered by SCS. A second aim was to compare skin conductance levels of patients with failed back surgery syndrome (FBSS) with age- and sex-matched healthy controls. Twenty-three patients with FBSS treated with SCS participated in this study. Sudomotor function was measured with the SudoscanTM instrument on the hands and feet during SCS on and off states. Difference scores in skin conductance between patients and age- and sex-matched healthy controls were calculated. Normal sudomotor function at the painful lower limb was revealed for 61% of the patients when SCS was activated. Skin conductance levels were not altered between on and off states of SCS. Differences in scores between patients and healthy controls were significantly different from zero. This study showed that SCS does not influencing the sympathetic nervous system in patients with FBSS, as measured by skin conductance levels. Moreover, it suggested that there is no normalization of the functioning of the sympathetic nervous system, despite the effectiveness of SCS to reduce pain intensity.

Throwing performance after high-velocity low-amplitude thrust manipulation at the cervicothoracic and thoracolumbar junction in elite female water polo players: a randomized blind cross-over study.

BACKGROUND: The effect of high-velocity low-amplitude (HVLA) thrust manipulation at the cervicothoracic and thoracolumbar junction in healthy elite female water polo players on throwing performance is unknown. METHODS: Ten healthy members of the Dutch National female water polo team participated in this randomized blind cross-over study. All received a HVLA manipulation and a sham manipulation at the cervicothoracic and thoracolumbar junction. Hereafter maximum throwing speed, range of motion and isometric strength were measured at 1 hour, 48 hours and 4 weeks follow-up. RESULTS: No significant differences in maximum throwing speed was found between HVLA and sham manipulation. In the non-dominant shoulder external rotation increased significantly (5.3±6.7°) 48 hours after sham manipulation, this effect was not considered clinically significant and diminished after four weeks. CONCLUSIONS: Our results suggest that HVLA and sham manipulation had no effect on shot velocity or shoulder mobility and the same effect on shoulder strength in healthy elite female water polo players. The common use of cervicothoracic and thoracolumbar HVLA manipulation for improving performance in this specific group of athletes is therefore questionable.

The interrelationship between grip work, self-perceived fatigue and pre-frailty in community-dwelling octogenarians.

INTRODUCTION: Low grip work and high feelings of self-perceived fatigue could be an early characteristic of decline in reserve capacity, which comes to full expression as physical frailty in a later stage. When grip work and self-perceived fatigue can be identified as characteristics differentiating between robustness and pre-frailty it might allow to identify pre-frailty earlier. Therefore, this study aimed to investigate whether the combination of grip work and self-perceived fatigue is related to pre-frailty in well-functioning older adults aged 80 and over. METHODS: Four-hundred and five community-dwelling older adults aged 80 and over (214 robust and 191 pre-frail) were assessed for muscle endurance (grip Work corrected for body weight (GW_bw)), self-perceived fatigue (MFI-20) and frailty state (Fried Frailty Index, FFI). A Capacity to Perceived Vitality ratio (CPV) was calculated by dividing GW_bw by the MFI-20 scores. ANCOVA analysis (corrected for age and gender) was used to compare robust and pre-frail older adults, and binary logistic regressions were applied to analyze the relationship between CPV and pre-frailty status. RESULTS: Pre-frail older adults who scored negative on the exhaustion item of the FFI still showed significantly lower GW (p < 0.001), CPV ratios (p < 0.001) and higher self-perceived fatigue (p < 0.05) compared to the robust ones. The likelihood for pre-frailty related significantly to higher age, being men and lower CPV ratios. In women, every unit increase in CPV ratio decreased the likelihood for pre-frailty by 78% (OR 0.22; 95% CI: 0.11-0.44), for men this effect was less strong (34%, OR 0.66; 95% CI: 0.47-0.93). CONCLUSIONS: Pre-frail community-dwelling persons aged 80 years and over without clinical signs of exhaustion on the FFI still experience significantly higher fatigue levels (lower Grip Work, higher self-perceived fatigue and lower CPV levels) compared to robust ones. CPV ratio could therefore be a good tool to identify subclinical fatigue in the context of physical (pre-)frailty.

Effectiveness of local exercise therapy versus spinal manual therapy in patients with patellofemoral pain syndrome: medium term follow-up results of a randomized controlled trial.

BACKGROUND: Increasing evidence has shown benefits of spinal manipulations in patients with patellofemoral pain syndrome (PFPS). There is scarcity regarding medium term effects of spinal manual therapy on outcome measures in PFPS patients. Therefore, the aim of the present study was to compare the effectiveness of local exercise therapy and spinal manual therapy for knee pain, function and maximum voluntary peak force (MVPF) velocity of the quadriceps in PFPS patients. METHODS: Forty-three patients with PFPS were randomly assigned to a local exercise or spinal manual therapy group. The local exercise group received six sessions (one session per week) of supervised training of the knee-and hip muscles with mobilization of the patellofemoral joint. The spinal manual therapy group received six interventions (one intervention per week) of high velocity low thrust manipulations at the thoracolumbar region, sacroiliac joint, and/or hip. All patients were also asked to do home exercises. Maximum, minimum and current pain were measured using the visual analogue scale. Function was assessed with the anterior knee pain scale (AKPS) and MPFV was recorded using a Biodex System 3 dynamometer. Patients were assessed before intervention, after 6 weeks of intervention and after 6 weeks of follow-up. Between-group differences at assessments were analysed by way of analysis of covariance with Bonferroni correction. RESULTS: Pain and functionality improved more following spinal manipulative therapy than local exercise therapy. After 6 weeks of intervention the between-group difference (local versus spinal) for maximal pain was 23.4 mm [95% CI: 9.3, 37.6; effect size (ES): 1.04] and - 12.4 [95% CI: - 20.2, - 4.7; ES: 1.00] for the AKPS. At 6 weeks of follow-up the between-group difference for maximal pain was 18.7 mm [95% CI: 1.4, 36.0; ES: 0.68] and - 11.5 [95% CI: - 19.9, - 3.3; ES: - 0.87] for the AKPS. CONCLUSIONS: This study suggests that spinal manual therapy is more effective than local exercise therapy in improving pain and function in patients with PFPS in the medium term. We suggest for future research to investigate whether combining local exercise therapy and spinal manual therapy is more effective than either single intervention on its own. This clinical trial study was approved by the Medical Ethics Committee METC Z under registration number NL57207.096. and registered retrospectively in ClinicalTrials.gov PRS with registration ID number NCT04748692 on the 10th of February 2021.

'External timing' of placebo analgesia in an experimental model of sustained pain.

BACKGROUND: Research on placebo analgesia commonly focuses on the impact of information about direction (i.e., increase or decrease of pain) and magnitude of the expected analgesic effect, whereas temporal aspects of expectations have received little attention so far. In a recent study, using short-lasting, low-intensity stimuli, we demonstrated that placebo analgesia onset is influenced by temporal information. Here, we investigate whether the same effect of temporal suggestions can be found in longer lasting, high-intensity pain in a Cold Pressor Test (CPT). METHODS: Fifty-three healthy volunteers were allocated to one of three groups. Participants were informed that the application of an (inert-)cream would reduce pain after 5 min (P5) or 30 min (P30). The third group was informed that the cream only had hydrating properties (NE). All participants completed the CPT at baseline and 10 (Test 10) and 35 min (Test 35) following cream application. Percentage change in exposure time (pain tolerance) from baseline to Test 10 (Δ10) and to Test 35 (Δ35) and changes in heart rate (HR) during CPT were compared between the three groups. RESULTS: Δ10 was greater in P5 than in NE and P30, indicating that analgesia was only present in the group that was expecting an early onset of analgesia. Δ35 was greater in P5 and P30 compared to NE, reflecting a delayed onset of analgesia in P30 and maintained analgesia in P5. HR differences between groups were not significant. CONCLUSIONS: Our data suggest that 'externally timing' of placebo analgesia may be possible for prolonged types of pain. SIGNIFICANCE: Research on placebo effects mainly focuses on the influence of information about direction (i.e., increase or decrease of pain) and magnitude (i.e., strong or weak) of the expected effect but ignores temporal aspects of expectations. In our study in healthy volunteers, the reported onset of placebo analgesia followed the temporal information provided. Such 'external timing' effects could not only aid the clinical use of placebo treatment (e.g., in open-label placebos) but also support the efficacy of active drugs.

Application of ultrasound for muscle assessment in sarcopenia: 2020 SARCUS update.

PURPOSE: In 2018, the SARCUS working group published a first article on the standardization of the use of ultrasound to assess muscle. Recommendations were made for patient positioning, system settings and components to be measured. Also, shortcomings in knowledge were mentioned. An important issue that still required standardization was the definition of anatomical landmarks for many muscles. METHODS: A systematic search was performed in Medline, SCOPUS and Web of Sciences looking for all articles describing the use of ultrasound in the assessment of muscle not described in the first recommendations, published from 01/01/2018 until 31/01/2020. All relevant terms used for older people, ultrasound and muscles were used. RESULTS: For 39 muscles, different approaches for ultrasound assessment were found that likely impact the values measured. Standardized anatomical landmarks and measuring points were proposed for all muscles/muscle groups. Besides the five already known muscle parameters (muscle thickness, cross-section area, pennation angle, fascicle length and echo-intensity), four new parameters are discussed (muscle volume, stiffness, contraction potential and microcirculation). The former SARCUS article recommendations are updated with this new information that includes new muscle groups. CONCLUSIONS: The emerging field of ultrasound assessment of muscle mass only highlights the need for a standardization of measurement technique. In this article, guidelines are updated and broadened to provide standardization instructions for a large number of muscles.

Equation models developed with bioelectric impedance analysis tools to assess muscle mass: A systematic review.

BACKGROUND & AIMS: This systematic review aims to systematically assess and summarize the equation models developed to estimate muscle mass with bioelectric impedance analysis (BIA) instruments against a reference instrument (DXA, MRI, CT-scan, Ultrasonography), in order to help researchers and clinicians choose the most adapted equation, depending on the device and the population in question. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement was followed. Medline (via Ovid) and Scopus were searched in January 2019 for observational (transversal, longitudinal, retrospective) studies developing an equation prediction model to validate BIA against another reference method for the assessment of muscle mass. Study selection and data extraction was performed independently by two researchers. Methodological quality of the included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. RESULTS: 25 studies matched the inclusion criteria and were included in the present systematic review. Among them, 10 studies proposed an equation for subjects aged 65 years and older, 9 for adults, 4 for infants and 2 did not report the age of the population. A large heterogeneity was observed regarding the brand and type of BIA as well as the administration protocol (mode, frequency, number of electrodes, administration position and empty bladder/stomach or not). Most of the studies used DXA as the reference instrument, except 4 that used MRI. In each of the included papers authors provided, through simple or multiple regression, a predictive equation for muscle mass. BIA resistance index, sex, weight, age, BIA reactance and height were most frequently included as predictive variables. The majority of the equations developed explained more than 80% of the variance between both instruments. Out of the 25 equations available, only 9 were also validated in another population within the same paper. CONCLUSION: This systematic review of the literature offers clinicians and researchers the opportunity to verify the existence of a prediction equation when using a BIA device for estimating muscle mass. This will help them to obtain a valid estimation of muscle mass in a specific population and with a specific instrument. If the equation exists and has been validated by a study free of high risk of bias, it's use is recommended because the development of a new equation in the same context seems redundant and undesirable. If a validation has not been carried out for a specific brand of BIA, reference method or population, we recommend the development and cross-validation of a new equation.