Off-Label Use of an External Hand Fixator for Craniomaxillofacial Fractures-An Anatomical Feasibility Study.

BACKGROUND: The lack of resources limits the treatment of craniomaxillofacial fractures (CMF) in low-income countries (LIC). Therefore, Barton bandages and/or interdental wiring are considered in these regions. Fracture reduction is maintained by permanent occlusion for 6 weeks, which often leads to limited compliance and dissatisfying results. The aim of this cadaver-based study is to evaluate the feasibility of the use of an external face fixator (EFF) for the treatment of CMF, its biomechanical values and to define the optimal pin insertion points and angles. MATERIALS AND METHODS: An AO hand fixator was used. CMF of types Le Fort 1-3 with split fractures of the hard palate were treated with EFF on 13 anatomical specimens. Fractures were created using a chisel, and pins were placed in specific anatomical regions. The maximal pull-out force [N] of pins was analysed by a tensile force gauge, and Fmax of the mandibular pins was evaluated. Computer tomography scans were performed on the healthy, fractured and EFF-treated skulls. RESULTS: The pull-out forces for the single pins were mandibular pins (n = 15, median 488.0 N), supraorbital pins (n = 15, median 455.0 N), zygomatic pins (n = 14, median 269.1 N), medial hard palate pins (n = 12, median 208.4 N) and lateral hard palate pins (n = 8, median 49.6 N). CONCLUSIONS: The results indicate that the operation technique is feasible, and the stability of the EFF is sufficient for maintaining the reduction. The required pins can safely be inserted into the described areas with good reduction results. Using EFF offers a feasible alternative to the non-surgical treatment of CMF in LIC.

The Impact of Exercise Training and Supplemental Oxygen on Peripheral Muscles in Chronic Obstructive Pulmonary Disease: A Randomized Controlled Trial.

OBJECTIVE: Exercise training is a cornerstone of the treatment of chronic obstructive pulmonary disease, whereas the related interindividual heterogeneity in skeletal muscle dysfunction and adaptations are not yet fully understood. We set out to investigate the effects of exercise training and supplemental oxygen on functional and structural peripheral muscle adaptation. METHODS: In this prospective, randomized, controlled, double-blind study, 28 patients with nonhypoxemic chronic obstructive pulmonary disease (forced expiratory volume in 1 second, 45.92% ± 9.06%) performed 6 wk of combined endurance and strength training, three times a week while breathing either supplemental oxygen or medical air. The impact on exercise capacity, muscle strength, and quadriceps femoris muscle cross-sectional area (CSA) was assessed by maximal cardiopulmonary exercise testing, 10-repetition maximum strength test of knee extension, and magnetic resonance imaging, respectively. RESULTS: After exercise training, patients demonstrated a significant increase in functional capacity, aerobic capacity, exercise tolerance, quadriceps muscle strength, and bilateral CSA. Supplemental oxygen affected significantly the training impact on peak work rate when compared with medical air (+0.20 ± 0.03 vs +0.12 ± 0.03 W·kg -1 , P = 0.047); a significant increase in CSA (+3.9 ± 1.3 cm 2 , P = 0.013) was only observed in the training group using oxygen. Supplemental oxygen and exercise-induced peripheral desaturation were identified as significant opposing determinants of muscle gain during this exercise training intervention, which led to different adaptations of CSA between the respective subgroups. CONCLUSIONS: The heterogenous functional and structural muscle adaptations seem determined by supplemental oxygen and exercise-induced hypoxia. Indeed, supplemental oxygen may facilitate muscular training adaptations, particularly in limb muscle dysfunction, thereby contributing to the enhanced training responses on maximal aerobic and functional capacity.

Responsiveness of Subcutaneous Fat, Intermuscular Fat, and Muscle Anatomical Cross-Sectional Area of the Thigh to Longitudinal Body Weight Loss and Gain: Data from the Osteoarthritis Initiative (OAI).

Thigh subcutaneous (SCF) and intermuscular (IMF) fat have been associated with joint health and function. Here, we explore the (sex-specific) responsiveness of SCF, IMF, and muscle during longitudinal weight loss and gain, as well as the change in questionnaire-based and physical performance-based knee function measures. This exploratory study included 103 Osteoarthritis Initiative (OAI) participants, who displayed a ≥10% weight loss or gain between baseline (BL) and 2-year (Y2) follow-up (and maintained half of that weight loss until year 4) and had axial 3T magnetic resonance images (MRI) for measuring SCF, IMF, and muscle cross sectional areas (CSAs). The standardized response mean (SRM = mean divided by the standard deviation of the change) was used as a measure of responsiveness. A total of 52 OAI participants (73% women) displayed ≥10% weight loss, and 51 (67% women) ≥10% weight gain. Both SCF and IMF CSAs showed a significant decrease (mean change) with weight loss (SCF: -22%, SRM = -1.2; IMF: -15%, SRM = -0.7) and a significant increase with weight gain (SCF: +27%, SRM = 1.1; IMF: +21%, SRM = 0.6). Muscle CSAs showed significant changes during weight loss (extensor: -8.3%, SRM = -1.1; flexor: -7.2%, SRM = -1.0), but not during weight gain. Knee function measures were not relevantly associated with bidirectional changes in body weight. SCF and IMF CSAs are highly responsive to bidirectional weight change, whereas muscle CSAs were only responsive to weight loss. These findings highlight that MRI represents a sensitive tool for monitoring changes in thigh adipose tissue composition that may be applied during specific diet and/or exercise interventions.

Local MRI-based measures of thigh adipose tissue derived from fully automated deep convolutional neural network-based segmentation show a comparable responsiveness to bidirectional change in body weight as from quality controlled manual segmentation.

BACKGROUND: Thigh intermuscular (IMF) and subcutaneous (SCF) fat are associated with joint function, inflammation and knee osteoarthritis. Fully automated segmentation from MRI is important to study the above relationship in larger cohorts. However, such algorithms are not clinically evaluated for longitudinal studies. Our aim was to evaluate a fully automated U-Net segmentation approach and its ability to detect longitudinal changes in thigh IMF and SCF during weight changes compared to manual segmentation. METHODS: 103 Osteoarthritis Initiative subjects, were studied, 52 with> 10% weight loss, and 51 with> 10% weight gain over 2-years. Longitudinal change in IMF and SCF were determined from baseline and year-2 axial thigh MRIs using U-Net segmentation. The standardised response mean (SRM) was used as measure of sensitivity to change. RESULTS: The U-Net took substantially less time (single-slice MRI:< 1 s) and IMF and SCF showed very similar sensitivity to change as manual segmentation: With an average weight gain of + 14%, we observed an + 12% /+ 26% increase in IMF / SCF (SRM=0.99 /1.03) using the U-Net, compared with + 21% /+ 27% (SRM=0.60 /1.07) for manual segmentation. During an average weight loss of - 18%, we observed an - 14% /- 22% reduction in IMF /SCF (SRM = - 1.04 /-1.20) using the U-Net, compared with - 16% /- 22% (SRM = - 0.70 /-1.23) for manual segmentation. CONCLUSION: U-Net segmentation replicates longitudinal changes of IMF and SCF associated with weight changes with a similar sensitivity to change as manual segmentation. This method is applicable to large databases for studying relationships between IMF and SCF and various disease conditions.

Is muscle strength in a painful limb affected by knee pain status of the contralateral limb? - Data from the Osteoarthritis Initiative.

Contralateral knee pain has been suggested to be associated with muscle weakness in a pain-free knee, potentially through a mechanism of central nervous inhibition. Whether contralateral knee pain also affects muscle strength in a painful knee, however, is unknown. Here we study the extent to which isometric muscle strength differs between matched painful limbs of people with unilateral knee pain vs. matched painful limbs people with bilateral knee pain. To that end, 163 participants with unilateral knee pain were identified from the Osteoarthritis Initiative. Unilaterally painful (UP) limbs were defined as having numerical rating scale (NRS) ≥4/10, infrequent/frequent pain in the painful limb, while contralateral pain-free limbs were defined by NRS=0-1, no/infrequent pain and Western Ontario and McMaster Universities Arthritis Index (WOMAC) ≤1. The comparator group were matched bilaterally painful (BP) limbs. Maximum isometric muscle strength (N) was compared between 1:1 matched BP and UP limbs. Extensor strength was found to be lower in BP limbs than in UP limbs, (-2.9%; p=0.39) but this difference was not statistically significant. Extensor strength was significantly lower in the UP vs. contralateral pain-free limbs (-6.2%; p<0.001). No differences were observed between BP and contralateral painful limbs (0.6%; p=0.87). In conclusion, the current results identify a slight reduction of maximum knee extensor strength in a painful limb, when the contralateral knee is also painful. In contrast to pain-free limbs, this effect did not reach statistical significance, but the overall findings support the concept of central nervous inhibition of muscle strength by contralateral knee pain.

Responsiveness of Infrapatellar Fat Pad Volume Change to Body Weight Loss or Gain: Data from the Osteoarthritis Initiative.

Obesity is a potent risk factor for knee osteoarthritis (OA) that is driven by mechanical and potentially endocrine mechanisms, and it affects women more frequently than men. The infrapatellar fat pat (IPFP) represents a potential link between obesity, intra-articular inflammation and structural pathology. Here we investigate whether the IPFP is responsive to body weight loss/gain in women and how its responsiveness to weight change compares to that of subcutaneous fat (SCF) of the thigh. All female participants of the Osteoarthritis Initiative (OAI) with ≥10% weight loss/gain between baseline and a 2-year follow-up were included. Within-subject changes in IPFP volume and SCF cross-sectional areas (CSA) were determined from 3-T magnetic resonance imaging. Linear regression was used to assess the association between change in weight, IPFP volume, and SCF CSA. In the 38 participants with ≥10% weight loss over 2 years (age 59.3 ± 9.1 years, mean loss = 15.9%), there was a significant reduction in IPFP volume (-2.2%, p = 0.02) as well as in SCF CSA (-22%, p < 0.001). In the 34 participants with ≥10% gain (age 61.5 ± 8.7 years, mean gain = 15.9%), there was a significant increase in SCF CSA (+26%, p < 0.001) but not in IPFP volume (0.2%, p = 0.87). Weight change was significantly associated with SCF CSA change (r = 0.76, p < 0.001) but not with IPFP volume change (r = 0.11, p = 0.37). In this first longitudinal, observational study investigating the responsiveness of IPFP and SCF to weight change, IPFP morphology was found responsive to weight loss but not to weight gain. Overall, the responsiveness of the IPFP was substantially less than that of the SCF.

Relationship Between Knee Pain and Infrapatellar Fat Pad Morphology: A Within- and Between-Person Analysis From the Osteoarthritis Initiative.

OBJECTIVE: Inflammation is known to be strongly associated with knee pain in osteoarthritis. The infrapatellar fat pad represents a potential source of proinflammatory cytokines. Yet the relationship between infrapatellar fat pad morphology and osteoarthritis symptoms is unclear. METHODS: Here we investigate quantitative imaging parameters of infrapatellar fat pad morphology between painful versus contralateral pain-free legs of subjects with unilateral knee pain and patients with chronic knee pain versus those of matched pain-free control subjects. A total of 46 subjects with strictly unilateral frequent knee pain and bilateral radiographic osteoarthritis (Kellgren/Lawrence grade 2/3) were drawn from the Osteoarthritis Initiative. Further, 43 subjects with chronic knee pain over 4 years and 43 matched pain-free controls without pain over this period were studied. Infrapatellar fat pad morphology (volume, surface area, and depth) was determined by manual segmentation of sagittal magnetic resonance images. RESULTS: No significant differences in infrapatellar fat pad morphology were observed between painful versus painless knees of persons with strictly unilateral knee pain (mean difference -0.7% (95% confidence interval [95% CI] -0.6, 0.9; P = 0.64) or between chronically painful knees versus matched painless controls (-2.1% [95% CI -2.2, 1.1]; P = 0.51). CONCLUSION: Independent of the ambiguous role of the infrapatellar fat pad in knee osteoarthritis (a potential source of proinflammatory cytokines or a mechanical shock absorber), the size of the infrapatellar fat pad does not appear to be related to knee pain.

Role of Breathing Conditions During Exercise Testing on Training Prescription in Chronic Obstructive Pulmonary Disease.

This study investigated whether different breathing conditions during exercise testing will influence measures of exercise capacity commonly used for training prescription in chronic obstructive pulmonary disease. Twenty-seven patients with chronic obstructive pulmonary disease (forced expiratory volume in 1 sec = 45.6 [9.4]%) performed three maximal exercise tests within 8 days, but at least 48 hrs apart. Subjects were thereby breathing either room air through a tightly fitting face mask like during any cardiopulmonary exercise test (MASK), room air without mask (No-MASK), or 10 l/min of oxygen via nasal cannula (No-MASK + O2). Cycling protocols were identical for all tests (start = 20 watts, increment = 10 males/5 females watts/min). Maximal work rate (90.4 [33.8], 100.3 [34.8], 107.4 [35.9] watts, P < 0.001) and blood lactate at exhaustion (4.3 [1.5], 5.2 [1.6], 5.0 [1.4] mmol/l, P < 0.001) were lowest for MASK when compared with No-MASK and No-MASK + O2, respectively, whereas maximal heart rate did not differ significantly. Submaximal exertion (Borg rating of perceived exertion = 12-14) was perceived at lower intensity (P = 0.008), but higher heart rate (P = 0.005) when MASK was compared with No-MASK and No-MASK + O2. Different breathing conditions during exercise testing resulted in an 18.8% difference in maximal work rate, likely causing underdosing or overdosing of exercise in chronic obstructive pulmonary disease. Face masks reduced whereas supplemental oxygen increased patients' exercise capacity. For accurate prescription of exercise in chronic obstructive pulmonary disease, breathing conditions during testing should closely match training conditions.

Variance in infra-patellar fat pad volume: Does the body mass index matter?-Data from osteoarthritis initiative participants without symptoms or signs of knee disease.

The infra-patellar fat pad (IPFP) has been proposed to represent an endocrine link between obesity and knee osteoarthritis (OA). The purpose of the current study has been to explore the extent to which IPFP volume is related to body mass index (BMI). A total of 152 participants (age 56±7 years) without knee OA were studied. These consisted of 19 men and 19 women of normal weight (BMI 18.5-25), 19/19 pre-obese (BMI 25-30), 19/19 obese class I (BMI 30-35) and 19/19 obese class II (BMI 35-40), who were matched 1:1 for age and height. The IPFP volume was manually segmented from sagittal fat-suppressed magnetic resonance images (MRI). An ANOVA of repeated measures was used to assess whether IPFP volume was related to BMI. The IPFP volume differed significantly between the BMI strata (ANOVA: p=0.001): It was 27.1±6.7cm3 (mean±SD) in normal weight, 29.3±6.9cm3 in pre-obese, 31.0±6.9cm3 in obese class I, and 30.4±6.6cm3 in obese class II participants; the difference in IPFP volume (and body weight) relative to normal weight subjects was 10% (18%) in pre-obese, 17% (39%) in obese class I, and 15% (59%) in obese class II participants. Stratification by sex showed similar results. In conclusion, IPFP volume is shown to be related to BMI, albeit the relative increase (compared with normal weight) does not appear to be proportional to that in body weight. Nonetheless, these findings support the hypothesis that the IPFP may represent a potential endocrine link between obesity and OA, with more intra-articular adipose tissue potentially releasing greater amounts of adipokines.

Supplemental Oxygen During High-Intensity Exercise Training in Nonhypoxemic Chronic Obstructive Pulmonary Disease.

BACKGROUND: Physical exercise training is an evidence-based treatment in chronic obstructive pulmonary disease, and patients' peak work rate is associated with reduced chronic obstructive pulmonary disease mortality. We assessed whether supplemental oxygen during exercise training in nonhypoxemic patients with chronic obstructive pulmonary disease might lead to superior training outcomes, including improved peak work rate. METHODS: This was a randomized, double-blind, controlled, crossover trial. Twenty-nine patients with chronic obstructive pulmonary disease (aged 63.5 ± 5.9 years; forced expiratory volume in 1 second percent predicted, 46.4 ± 8.6) completed 2 consecutive 6-week periods of endurance and strength training with progressive intensity, which was performed 3 times per week with supplemental oxygen or compressed medical air (flow via nasal cannula: 10 L/min). Each session of electrocardiography-controlled interval cycling lasted 31 minutes and consisted of a warm-up, 7 cycles of 1-minute intervals at 70% to 80% of peak work rate alternating with 2 minutes of active recovery, and final cooldown. Thereafter, patients completed 8 strength-training exercises of 1 set each with 8 to 15 repetitions to failure. Change in peak work rate was the primary study end point. RESULTS: The increase in peak work rate was more than twice as high when patients exercised with supplemental oxygen compared with medical air (0.16 ± 0.02 W/kg vs 0.07 ± 0.02 W/kg; P < .001), which was consistent with all other secondary study end points related to exercise capacity. The impact of oxygen on peak work rate was 39.1% of the overall training effect, whereas it had no influence on strength gain (P > .1 for all exercises). CONCLUSIONS: We report that supplemental oxygen in nonhypoxemic chronic obstructive pulmonary disease doubled the effect of endurance training but had no effect on strength gain.

Effects of a 12-week alpine skiing intervention on endothelial progenitor cells, peripheral arterial tone and endothelial biomarkers in the elderly.

OBJECTIVE: Endothelial dysfunction occurs early during atherogenesis and it can be normalized by exercise training. Unfortunately, patients' compliance with exercise prescription remains low, often because the given choices do not appeal to them. In Alpine regions, skiing is a popular mode of exercise, and therefore we set out to assess whether it can induce antiatherogenic effects. METHODS: We randomized 42 subjects into a group of 12weeks of guided skiing (intervention group, IG, n=22; 12 males/10 females; age: 66.6±2.1years) or a control group (CG, n=20; 10 males/10 females; age: 67.3±4.4years). Early (CD3-CD34+CD45+) and late endothelial progenitor cells (EPCs; CD45dimCD34+KDR+ peripheral blood mononuclear cells, PBMCs), peripheral arterial tonometry and endothelial biomarkers were assessed at the beginning and end of the study. RESULTS: In the IG, participants completed 28.5±2.6 skiing days at an average heart rate of 72.7±8.5% of their maximum heart rate. Changes in early (IG: +0.001±0.001% PBMC; CG: -0.001±0.001% PBMC; IG vs. CG: p<0.001) but not late EPCs differed significantly. Changes in peripheral arterial tone differed significantly between IG (Reactive Hyperemia Index: +0.18±0.76) and CG (-0.39±0.85; p=0.045), as did homocysteine (IG: -1.3±1.3µmol/l; CG: -0.4±1.4µmol/l; p=0.037) while other endothelial biomarkers remained essentially unchanged. CONCLUSIONS: This study shows that skiing induces several beneficial effects on markers of atherogenesis including EPCs, peripheral arterial tone and homocysteine. Our findings suggest that recreational alpine skiing may serve as a further mode of preventive exercise training, which might result in improved compliance with current recommendations.

Does exercise training impact clock genes in patients with coronary artery disease and type 2 diabetes mellitus?

BACKGROUND: Recent findings revealed negative effects of deregulated molecular circadian rhythm in coronary artery disease (CAD) and type 2 diabetes mellitus (T2DM). Physical exercise training (ET) has been shown to promote anti-diabetic and anti-atherogenic responses in skeletal muscle of these patients, but the role of the circadian clock-machinery remains unknown. This study investigated whether mRNA expression of clock genes in skeletal muscle of CAD and T2DM patients is influenced by physical ET intervention. METHODS: Nineteen patients with CAD and T2DM (age 64 ± 5 years) were randomised to either six months of ET (four weeks of in-hospital ET followed by a five-month ambulatory programme) or usual care. At the beginning of the study, after four weeks and after six months parameters of metabolic and cardiovascular risk factors, and physical exercise capacity were assessed. Gene expression was measured in skeletal muscle biopsies by quantitative real-time polymerase chain reaction (PCR). RESULTS: A selection of clock genes and associated components (circadian locomoter output cycle kaput protein (CLOCK), period (PER) 1, cryptochrome (CRY) 2 and aminolevulinate-deltA-synthase-1 (ALAS1)) was reliably measured and used for further analysis. A time-dependent effect in gene expression was observed in CLOCK (p = 0.013) and a significant interaction between time and intervention was observed for ALAS1 (p = 0.032; p = 0.014) as a result of ET. CONCLUSION: This is the first study to analyse clock gene expression in skeletal muscles of patients with CAD and T2DM participating in a long-lasting exercise intervention. ET, as one of the cornerstones in prevention and rehabilitation of CAD and T2DM, exerts no effects on CLOCK genes but meaningful effects on the clock-associated gene ALAS1.

Is Pain in One Knee Associated with Isometric Muscle Strength in the Contralateral Limb?: Data From the Osteoarthritis Initiative.

OBJECTIVE: Knee pain and muscle weakness confer risk for knee osteoarthritis incidence and progression. The purpose of this study was to determine whether unilateral knee pain influences contralateral thigh muscle strength. DESIGN: Of 4796 Osteoarthritis Initiative participants, 224 (mean ± SD age, 63.9 ± 8.9 yrs) cases could be matched to a control. Cases were defined as having unilateral knee pain (numerical rating scale, ≥ 4/10; ≥infrequent pain) and one pain-free knee (numerical rating scale, 0-1; ≤infrequent pain; Western Ontario and McMaster Universities Arthritis Index, ≤ 1). Controls were defined as having bilaterally pain-free knees (numerical rating scale, 0-1; ≤infrequent pain; Western Ontario and McMaster Universities Arthritis Index, ≤ 1). Maximal isometric muscle strength (N) was compared between limbs in participants with unilateral pain (cases) as well as between pain-free limbs of cases and controls. RESULTS: Knee extensor/flexor strength in pain-free limbs of the cases was lower than that in bilaterally pain-free controls (-5.5%/-8.4%; P = 0.043/P = 0.022). Within the cases, maximum extensor/flexor strength was significantly lower in the painful limb than in the pain-free limb (-6.3%/4.1%; P < 0.0001/P = 0.015). CONCLUSIONS: These results suggest that strength in limbs without knee pain is associated with the pain status of the contralateral knee. The strength difference between unilateral pain-free cases and matched bilateral pain-free controls was similar to that between limbs in persons with unilateral knee pain. Lower strength caused by contralateral knee pain might be centrally mediated.