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This study evaluated the frequency, and effect of physiological 2-deoxy-2-[fluorine-18] fluoro-D-glucose (FDG) tracer injection and its association with the penetration rates of mobile devices. This retrospective analysis included 213 patients (mean age ± standard deviation, 66.2 ± 14.1 years; range 23–93 years; 125 men) who underwent FDG-positron emission tomography examination. Elevated FDG activity in the thenar eminence with maximum standardized uptake value (SUVmax) ≥ 2.5 was considered positive. Differences according to age, sex, laterality, and tracer injection side were evaluated using Fisher’s exact test. Associations were assessed using Pearson’s correlation coefficient. Twenty-three percent (49/213) of the patients had elevated FDG activity in the thenar eminence (mean SUVmax, 3.50 ± 1.04; range 2.5–6.3), including 18 with bilateral findings. No significant difference existed according to age (

Aim of the study: The purpose of this study was to investigate the effects of receptor density in the glabrous skin of the hand on the perception of the roughness of a textured surface.Materials and methods: This was done by having observers make magnitude estimates of the perceived roughness of raised-dot surfaces at the fingertip, with its high receptor density, and the thenar eminence, with its much lower receptor density.Results: Judgments of perceived roughness averaged over the inter-dot spacings (0.8-5.9 mm) employed in the study did not differ significantly between the two sites, which suggested that roughness perception is not exclusively dependent upon a neural code involving variation in the activity levels of the nerve fibers of spatially distributed receptors, as is the case in spatial discrimination tasks such as spatial-gap detection, grove-orientation discrimination and letter recognition. This hypothesis was further supported by the finding that the elimination of temporal cues by preventing movement of the skin over the raised-dot surface drastically impaired judgments of perceived roughness at the thenar but had little effect on judgments of perceived roughness at the fingertip.Conclusion: These findings suggested that the neural code for perceived roughness at the fingertip is mediated primarily by spatial variation in the activity levels of spatially distributed receptors whereas the neural code for perceived roughness at the thenar is mediated primarily by temporal variation in the activity levels of individual receptors.

Background: The purpose of this study was to investigate the effect of general anesthesia on microvascular reactivity and tissue oxygen saturation (StO2) using near-infrared spectroscopy in conjunction with vascular occlusion tests (VOT). Age-related changes of microvascular reactivity, that is, the capacity of capillary recruitment, were examined. Methods: This prospective observational study was performed on 60 patients without comorbidities who underwent elective surgery under general anesthesia. Baseline StO2 on thenar eminence, hemodynamics, and laboratory profile were monitored before (T0) and 30 min after general anesthesia (T1). During VOT, occlusion slope representing oxygen consumption of muscle and recovery slope representing microvascular reactivity were also collected at T0 and T1. Results: Baseline StO2 and minimum / maximum StO2 during VOT increased under general anesthesia. Occlusion slope decreased while the recovery slope increased under general anesthesia. To observe aging effect, Receiver operating characteristic analysis was performed and age less than 65 years old showed a fair performance in predicting the increase of microvascular reactivity after the induction of anesthesia (AUC 0.733, 95% CI 0.594-0.845, P= 0.003). For age-related analyses, 27 patients of younger group (< 65 years) and 26 patients of older group (≥ 65 years) were divided. Recovery slope significantly increased under general anesthesia in younger group (2.44 [1.91-2.81] % ∙ sec-1 at T0 and 3.59 [2.58-3.51] % ∙ sec-1 at T1, P

Introduction and Aims: The movements of the thumb are carried out by three muscles originating from the forearm viz., two extensors (a longus and a brevis) and an abductor. Anatomical variation has been observed in one out of every six cadavers. Among the muscles of the thumb the abductor is commonly known to show such variations. Aim of this report is to present the frequency of variations in local population. Materials and Methods: The data for the present study was collected by dissection of fifty hands (30 adult and 20fetal).Tendon slips of each of the three muscles were counted and their width was measured with a calliper. Observations: A single tendon slip of extensor pollicis longus was found in 43 (86%) hands, and in seven (14%) the tendon slip was duplicated. The extensor pollicis brevis tendon was found to have a single slip in 47 (94%) hands and in three (6%) the tendon slip was duplicated. The abductor pollicis longus tendon (APL) had a single slip in 38(76%) hands, double and triple together in 11(22%). The APL was absent in one (2%) hand. In one adult male the APL had three slips of origin; anterior slip formed a fusiform belly attached to the base of the proximal phalanx. On the left side of the same cadaver the muscle had two slips, the anterior slip divided into two, one of these ended in a fusiform belly within the thenar eminence. Conclusions: Knowledge of anatomical variations of the tendons of the thumb is essential during the surgical repair and in cases where tendon transfer is required. Multiple tendons are known to cause conditions like de Queverain's syndrome. Keywords: Thumb, Extensors, Forearm, Variations.

Highlights • Isolated Trapezium fracture is difficult to be detected causing 1st carpometacarpal joint degeneration and limitation of thumb motion. • In order not to miss trapezium fracture, a high index of suspicion is required. • Persistent pain in the anatomical snuffbox or thenar eminence following a trauma should alert the physician to consider trapezium fracture. • Open reduction and internal fixation even without graft seem to be a plausible choice for managing comminuted trapezium fracture., Introduction and importance Trapezium, as a carpal bone positioned at the distal row, is often associated with other wrist injuries such as distal radius fracture. Isolated trapezium fracture, especially in a comminuted form, rarely occurs. There are only six reports of isolated comminuted trapezium fractures in the literature to the best of our knowledge. Case presentation We present a case with an isolated comminuted trapezium fracture presenting pain in his thenar eminence and thumb motion limitation. He was treated by Open Reduction and Internal Fixation (ORIF) with the K wire pin. Clinical discussion We searched the published related studies and summarized the signs and symptoms of patients presented with trapezium fracture. The most common presentation of trapezial fracture include pain/tenderness at the base of the first metacarpal bone, pain/tenderness at the snuffbox area and 1st digit motion limitation. The treatment options described in the literature for isolated comminuted trapezium fracture are also presented. Open reduction and fixation with pin is the most common treatment mentioned in the literature. The priority is restoring the scaphotrapezial and trapeziometacarpal joint congruency to save the 1st digit range of motion. Conclusion Comminuted trapezial fracture may happen following either low energy (like our patient) or high energy trauma. This paper highlights the fact that even a comminuted trapezium fracture can be easily missed. Regardless of the trauma mechanism (high energy versus low energy trauma), a high index of suspicion and delicate work up would be necessary in order not to miss this type of fracture.

Background The diagnosis of temporomandibular disorders (TMD) is based on patient history and physical examination, and may require medical imaging. Masticatory muscle palpation is essential to make a diagnosis of TMD. However, the response of masticatory muscles to mechanical pressure stimuli depends on many physical and psychological factors. Objective This study aimed at determining the impact of somatosensory amplification (SSA)-an estimate of somatic awareness and bodily hypervigilance-on pressure pain thresholds (PPTs) measured at both trigeminal and extra-trigeminal locations in healthy individuals. Methods PPTs were measured at the right anterior temporalis and superficial masseter, and the thenar eminence of the right hand in one hundred healhty individuals (69F, 31M), divided in three groups based on their SSA scores: low (N = 32), intermediate (N = 34) and high (N = 34). General linear models were used to test between-group differences in PPTs including sex as a covariate. The level of significance was set at P Results Individuals with high SSA had lower PPTs at the anterior temporalis than individuals with low (P = .006) and intermediate (P = .001) SSA. No significant between-group differences were found in PPTs measured at the masseter (P = .372). PPTs measured at the thenar eminence were significantly lower in the high than the low SSA group (P = .009). Females had lower PPTs at the masseter than males (P = .021) but not at other muscle locations (all P > .05). Conclusion Increased somatosensory amplification is associated with decreased pressure pain thresholds at both trigeminal and extra-trigeminal locations in healthy individuals. SSA could be a potential confounder while diagnosing TMD and evaluating treatment outcomes.

Background Neurogenic thoracic outlet syndrome treatments have high morbidity and recurrence rates. We present for the first time to our knowledge a minimally invasive spine surgery technique for complete resection of a cervical rib via a costotransversectomy approach. Case Description A patient with an 8-year history of progressive thoracic outlet syndrome presented with right C8 pain, weakness, and atrophy of her right forearm and thenar eminence. After neurogenic thoracic outlet syndrome was confirmed via electromyography and imaging revealed bilateral cervical ribs (right more than left), the patient underwent a minimally invasive spine surgery resection of the rib via a costotransversectomy and was discharged home the same day. The patient's pain and weakness gradually improved over a 2-year follow-up period. Conclusions Resection of a cervical rib via minimally invasive spine surgery costotransversectomy is safe and well tolerated compared with existing surgical treatments such as transaxillary, supraclavicular, and infraclavicular approaches.

Background Weaning from mechanical ventilation (MV) is a cardiovascular stress test. Monitoring the regional oxygenation status has shown promising results in predicting the tolerance to spontaneously breathe in the process of weaning from MV. Our aim was to determine whether changes in skeletal muscle oxygen saturation (StO2) measured by near-infrared spectroscopy (NIRS) on the thenar eminence during a vascular occlusion test (VOT) can be used to predict extubation failure from mechanical ventilation. Methods We prospectively studied 206 adult patients with acute respiratory failure receiving MV for at least 48 h from a 30-bed mixed ICU, who were deemed ready to wean by their physicians. Patients underwent a 30-min spontaneous breathing trial (SBT), and were extubated according to the local protocol. Continuous StO2 was measured non-invasively on the thenar eminence. A VOT was performed prior to and at 30 min of the SBT (SBT30). The rate of StO2 deoxygenation (DeO2), StO2 reoxygenation (ReO2) rate and StO2 hyperemic response to ischemia (HAUC) were calculated. Results Thirty-six of the 206 patients (17%) failed their SBT. The remainder 170 patients (83%) were extubated. Twenty-three of these patients (13.5%) needed reinstitution of MV within 24 h. Reintubated patients displayed a lower HAUC at baseline, and higher relative changes in their StO2 deoxygenation rate between baseline and SBT30 (DeO2 Ratio). A logistic regression-derived StO2 score, combining baseline StO2, HAUC and DeO2 ratio, showed an AUC of 0.84 (95% CI 0.74–0.91) for prediction of extubation failure. Conclusions Extubation failure was associated to baseline and dynamic StO2 alterations during the SBT. Monitoring StO2-derived parameters might be useful in predicting extubation outcome.

Manipulation of objects after grasping is an important research topic for robotic hands. In this research, we propose a grip method based on the thenar opposition, which is rarely handled in the fr...

Studies evaluating sensory function of the entire trigeminocervical region in patients with cluster headache (CH), migraine (MH), and tension-type headache (TH) are required. The purpose of the present study was to evaluate and compare sensory function in the trigeminocervical region in patients with CH, MH, and TH and healthy controls (HC).Quantitative sensory testing (QST), including pressure pain threshold (PPT), tactile detection threshold (TDT), prick detection threshold (PDT), and two-point detection threshold (2PDT), was evaluated in 139 patients with headache (CH = 16, MH = 52, TH = 71) and 30 HC. Test sites included bilaterally the first, second, and third divisions of trigeminal nerve (V1, V2, and V3), cervical spine, and thenar eminence.TH presented significantly lower PPT values compared with CH (p 0.015), MH (p 0.048), and HC (p 0.009), while MH demonstrated significantly lower values than HC (p = 0.001-0.023). When analyzing TDT, CH in the symptomatic side presented significantly higher values in V1 compared with MH (p = 0.001), TH (p 0.001), and HC (p 0.001) and in V2 compared with TH (p = 0.035). No statistically significant differences were found for PDT (p 0.005). With regard to 2PDT, CH-s presented significantly higher values in V1 with respect to HC (p = 0.016) but lower values in V2 compared with MH (p 0.001) and TH (p = 0.003).The results of the present study indicate specific and different altered mechanical sensory thresholds in CH, MH, and TH patients compared with HC subjects.

Purpose When performing endoscopic thoracic sympathectomy (ETS) in palmar hyperhidrosis patients, a device can be used to measure sweat volume pre- and postoperatively in order to assess indications and treatment effects. In this study, we measured changes in the dynamics of sweating in hyperhidrosis patients pre- and postoperatively and compared the values with those in healthy subjects without hyperhidrosis. Methods The patient group comprised 25 persons with palmar hyperhidrosis who were scheduled for ETS. The dynamics of sweating was measured at 1 day prior to surgery and at 2 days postoperatively, in 18 patients at > 1 year postoperatively in another palmar hyperhidrosis group, and in 20 healthy subjects without hyperhidrosis. A device for measuring local sweat volume was applied at the thenar eminence of both palms. Indicators established were basal sweat rate (BSR; mg/min/cm2), peak sweat rate (PSR; mg/min/cm2) during mental stress (sympathetic sweating response), sweat volume (SV), and sweat time (ST; s). Results After surgery, all of the indicators were significantly reduced in hyperhidrosis patients and there was very little response to mental stress. The subgroup of these patients assessed at > 1 year after ETS showed a trend of increased BSR similar to that of healthy subjects. These changes did not correlate with the extent of the removal surgery. Preoperatively, hyperhidrosis patients had significantly greater BSR, PSR, and SV and longer ST than healthy subjects. Conclusion All of the sweating parameters were increased in palmar hyperhidrosis patients prior to surgery. Immediately after ETS, all these parameters were significantly reduced. At > 1 year after ETS, the BSR had increased to a level similar to that of the healthy volunteers, although PSR did not respond to mental stress.

Background Temporal summation (TS) refers to the increased perception of pain with repetitive noxious stimuli. While thermal TS is generally considered a behavioral correlate of spinal windup, noxious heat pulses also trigger additional sensory processes which were modeled in this study. Methods Nineteen healthy volunteers (9 females, mean age 29.2, SD 10.5) underwent two identical TS experiments, spaced a week apart. The TS paradigm consisted of 10 identical heat pulses with individualized temperatures at the thenar eminence (0.5Hz). We extracted 3 features from continuous TS response curves: Lag, time to first feel pain; Slope, the rate of pain increase between the first and most painful heat pulse; and Delta, the maximum drop in pain after peak pain is reached. We then examined the within-individual stability of these features, followed by the Pearson's correlations among these features and between the features and negative affect. Results All 3 features were stable over 1 week. Lag and Delta were negatively correlated (r = -0.5, p = 0.042). Slope did not correlate with Lag or Delta, but strongly correlated with a traditional TS measure, first pulse pain and peak pain difference (r = 0.91, p < 0.0001). Negative affects such as trait and state anxiety were negatively correlated with baseline (r = -0.49, p = 0.031) and peak stimulating temperature (r = -0.48, p = 0.039), respectively, suggesting an association between anxiety and greater pain sensitivity. Conclusion We were able to decouple spinal windup from other perceptual processes generated by phasic thermal TS paradigms and demonstrate temporal stability of these curve features. These curve features may help better characterize the complex sensory response to noxious heat pulses and serve as biomarkers to profile patients with chronic pain.

BACKGROUND Within the thenar eminence, the median nerve innervates three muscles: abductor pollicis brevis (APB), flexor pollicis brevis (FPB), and opponens pollicis (OP). Of these muscles, APB was often considered as the sole contributor to the thenar compound muscle action potential (CMAP). OBJECTIVE To evaluate subcomponents of the thenar CMAP from the median nerve innervated muscles. METHODS Surface and needle CMAPs were recorded in normal human subjects from three recording sites: proximal (site-I), middle (site-II), and distal (site-III) aspects of the thenar eminence when the median nerve was activated at the wrist. RESULTS In the site-I and -II, both the surface and needle CMAPs shared many similar characteristics although the needle CMAPs were larger (∼ 5 folds) and briefer (∼ 60%, needle/surface duration). In addition, on the surface recording, the CMAP was larger (by ∼ 1.9 mV) when recorded from the site-I comparing to that of the site-II. In the site-III, the surface recordings registered a delayed (by ∼ 3.8 ms) CMAP. The muscle fiber action potential (MFAP) study suggested a predominant FPB contribution in the site-III. CONCLUSION The optimal recording site for APB derived thenar CMAP is the site-I and for FPB is the site-III. The CMAPs registered by the needle recordings are more robust than the surface ones.

Aims Nurses' hand temperature may affect patient comfort but has not been investigated. This study aimed to determine female hospital nurses' hand skin temperature and clarify the effects of measurement site, time, nursing procedures, and environment. Design An observational study. Methods The middle finger, thenar eminence, hypothenar eminence, and medial forearm skin temperature of 29 female hospital nurses was measured at four time points during a day shift and before and after nursing procedures (hand disinfection, hand washing, taking vital signs, hygiene care, and positioning). Results Mean hand skin temperature was in the range of 29-32°C with interpersonal variations. Mean skin temperature at the medial forearm was 31.94-32.35°C (SD 0.87-1.52°C) and at the middle finger, 29.73-31.07°C (SD > 3°C). Time-dependent skin temperature fluctuations were confirmed on the middle finger (p = .022), and thenar (p = .005) and hypothenar eminence (p = .001). There were weak correlations between skin temperature and environmental factors, including ambient temperature (ρ = .194-.266), humidity (ρ = -.309 to -.319), and hospital room wind speed (ρ = .253-.314). The skin temperature dropped significantly after hand disinfection and handwashing at all measurement sites (middle finger: -1.30 and -3.56°C, respectively; thenar eminence: -1.19 and -3.32°C; hypothenar eminence: -0.80 and -3.39°C; medial forearm: -0.21 and -1.60°C). Conclusion These findings may raise nurses' awareness of their skin temperature. Moreover, our study highlights the need to develop countermeasures to ensure optimal nurses' skin temperature and patient comfort.

We report the case of a thenar eminence arteriovenous malformation presenting with continuous growth and pain that was treated with surgical excision after embolization. Extracapsular resection compromised thenar muscles which function was reconstructed with extensor indicis proprius transfer for opposition and abduction, and neurotized free gracilis muscle flap for opposition and adduction, as well as thenar eminence reconstruction.

Background Bowen's disease (BD) is a persistent, progressive intraepidermal carcinoma. BD usually occurs in areas exposed to sunlight. Involvement of the dorsum of the hand is not rare, but that of the palmar aspect is very unusual. Only a few cases have been reported in the literature. Case summary Here, we report the case of a 48-year-old male patient who presented with a history of persistent local erythema lasting for 2 years on the thenar eminence of the left palm. Initially diagnosed as hand eczema, the condition did not improve with intermittent treatment with anti-allergy medications or topical glucocorticoid ointments, among other approaches. Then, the area of erythema gradually enlarged and was accompanied by mild itching. For a definite diagnosis and treatment, the patient came to our hospital. Dermoscopic examination revealed BD, and histopathological examination confirmed the diagnosis. We performed partial resection of the skin lesion followed by photodynamic therapy. No recurrence was observed at the 6-mo follow-up. Conclusion For all atypical palmar lesions, early dermoscopy and/or skin biopsy are needed to avoid missed diagnosis or misdiagnosis.

Background/Objectives: The allocation of attention can alter the perception of magnitude. When performing line bisections, young adults deviate leftward (pseudoneglect), a bias thought to be induced by right hemisphere dominance for allocating spatial attention. However, when performing body bisections young adults deviate rightward, suggesting left hemisphere dominance for allocating body-centered attention. With aging, there is a reduction of pseudoneglect thought to result from either an age-related decrease in right hemispheric functions (right hemi-aging) or from hemispheric asymmetry reduction in older adults (HAROLD). The goal of this study was to learn if there are tactile body-centered perceptual-attentional right-left asymmetries in that change with aging. Methods: The participants were younger and older healthy adults. Semmes-Weinstein Monofilaments were used to test for differences in the perceived magnitude of pressure differences between a reference stimulus and test stimuli applied to the right and left palmar thenar eminence. Results: Young adults perceived the magnitude of difference in the lightest pressure stimuli applied to the right hand as being greater than the older adults. Young adults perceived the magnitude of difference between the lightest pressure and reference applied to the right hand to be greater than the left hand, but older adults perceived a lighter stimulus greater on the left compared to the right. Conclusions: Whereas the right hemisphere appears to be dominant in mediating spatial attention, the left hemisphere may play a dominant role in the allocation of body-centered attention. Like the aging-related reduction of the visual perception of the magnitude (length) of the left side of a line, this tactile reduction in magnitude (pressure) perception in older adults suggests that with aging, there is a reduction of left-hemispheric mediated allocation of tactile attention, and this result is not fully consistent with either the HAROLD or hemi-aging models.

Heart failure (HF) is associated with microcirculatory changes secondary to neuro-humoral imbalance, vascular stiffness and increased sympathetic tone. Near Infra-Red Spectroscopy (NIRS) derived Thenar muscle tissue oxygenation levels (StO(2)) can provide an estimate of the functional status of microcirculation. There is a paucity of literature regarding evaluation of microcirculation in pediatric subjects with HF. We hypothesized that microcirculation and oxygen saturation dynamics as assessed by Thenar StO(2) levels using vascular occlusion test (VOT) would be altered in HF subjects and that these changes may correlate with the severity of heart failure. We prospectively enrolled 60 pediatric subjects (29 healthy control, 31 HF). Baseline StO(2) levels were measured using InSpectra™ StO(2) probe placed over the Thenar eminence of right hand, followed by a VOT for 3 min, during which the changes in StO(2) levels during the occlusion phase and post occlusion phase were recorded. Baseline Thenar StO(2) levels (72 ± 8 vs 76 ± 5, p = 0.02) and time to baseline StO(2) in seconds (150 ± 70 vs 200 ± 70, p = 0.007) were significantly lower in HF group compared to healthy control (HC). In addition, HF patients had a significantly lower trough StO(2) (37 ± 9 vs 42 ± 11%, p = 0.04) and peak StO(2) compared to HC (87 ± 8 vs 91 ± 5%, p = 0.01). However, there was no difference in the rate of desaturation, rate of resaturation or time to peak StO(2) levels in between the 2 groups. Significant correlation was present between baseline Thenar StO(2) levels and NYU Pediatric Heart Failure Index Score (NYU-PHFI) (p = 0.003). This study is the first to report an objective assessment of microcirculation and Thenar tissue oxygen dynamics in pediatric subjects with HF in comparison with HC. Our study suggests altered microcirculation and oxygenation patterns in these subjects as well as correlation with a validated pediatric heart failure clinical score. Large-scale prospective studies are needed to further study the utility of this novel technology in HF subjects.

Objectives Systemic sclerosis (SSc) causes functional and structural microcirculatory dysfunction, affecting also distal extremities. Optical Near-InfraRed Spectroscopy (NIRS) of blood HbO2 saturation (stO2) is able to evaluate O2 delivery/consumption balance in the explored tissue. The NIRS-sensitive camera non-invasively detects stO2 values in superficial tissues, automatically generating 2D-imaging maps in real time. We aimed at testing whether NIRS hand imaging may evaluate peripheral microcirculatory dysfunction and its spatial heterogeneity in SSc patients compared to controls. Methods Forty SSc patients (aged 55.1 ± 15.6 years) and twenty-one healthy controls (aged 54.3 ± 14.5years, p = 0.89) were studied by palmar hand NIRS-2D imaging. A blood pressure cuff was applied to the forearm and 3 min ischemia was induced. Images were acquired at basal conditions and every 10 seconds during 3 minutes of ischemia and 5 minutes of reperfusion. Five regions of interest were positioned on each fingertip, from the second to the fifth finger and one on the thenar eminence. Results A significant difference was found between controls and SSc patients in basal stO2 (84.3 ± 7.5 vs. 75.4 ± 10.9%, p Conclusion NIRS-2D imaging is a simple, automated tool to non-invasively detect regional microcirculatory impairment in SSc, which seems to add significant functional information to the morphological picture of nailfold-videocapillaroscopy.