The Chemokine Receptor CX3CR1 Defines Three Antigen-Experienced CD8 T Cell Subsets with Distinct Roles in Immune Surveillance and Homeostasis.

Infections induce pathogen-specific T cell differentiation into diverse effectors (Teff) that give rise to memory (Tmem) subsets. The cell-fate decisions and lineage relationships that underlie these transitions are poorly understood. Here, we found that the chemokine receptor CX3CR1 identifies three distinct CD8+ Teff and Tmem subsets. Classical central (Tcm) and effector memory (Tem) cells and their corresponding Teff precursors were CX3CR1- and CX3CR1high, respectively. Viral infection also induced a numerically stable CX3CR1int subset that represented ∼15% of blood-borne Tmem cells. CX3CR1int Tmem cells underwent more frequent homeostatic divisions than other Tmem subsets and not only self-renewed, but also contributed to the expanding CX3CR1- Tcm pool. Both Tcm and CX3CR1int cells homed to lymph nodes, but CX3CR1int cells, and not Tem cells, predominantly surveyed peripheral tissues. As CX3CR1int Tmem cells present unique phenotypic, homeostatic, and migratory properties, we designate this subset peripheral memory (tpm) cells and propose that tpm cells are chiefly responsible for the global surveillance of non-lymphoid tissues.

Deep Learning-Based Spermatogenic Staging in Tissue Sections of Cynomolgus Macaque Testes.

The indirect assessment of adverse effects on fertility in cynomolgus monkeys requires that tissue sections of the testis be microscopically evaluated with awareness of the stage of spermatogenesis that a particular cross-section of a seminiferous tubule is in. This difficult and subjective task could very much benefit from automation. Using digital whole slide images (WSIs) from tissue sections of testis, we have developed a deep learning model that can annotate the stage of each tubule with high sensitivity, precision, and accuracy. The model was validated on six WSI using a six-stage spermatogenic classification system. Whole slide images contained an average number of 4938 seminiferous tubule cross-sections. On average, 78% of these tubules were staged with 29% in stage I-IV, 12% in stage V-VI, 4% in stage VII, 19% in stage VIII-IX, 18% in stage X-XI, and 17% in stage XII. The deep learning model supports pathologists in conducting a stage-aware evaluation of the testis. It also allows derivation of a stage-frequency map. The diagnostic value of this stage-frequency map is still unclear, as further data on its variability and relevance need to be generated for testes with spermatogenic disturbances.

COVID-19 disease in hospitalized young adults in India and China: Evaluation of risk factors predicting progression across two major ethnic groups.

Data pertaining to risk factor analysis in coronavirus disease 2019 (COVID-19) is confounded by the lack of data from an ethnically diverse population. In addition, there is a lack of data for young adults. This study was conducted to assess risk factors predicting COVID-19 severity and mortality in hospitalized young adults. A retrospective observational study was conducted at two centers from China and India on COVID-19 patients aged 20-50 years. Regression analysis to predict adverse outcomes was performed using parameters including age, sex, country of origin, hospitalization duration, comorbidities, lymphocyte count, and National Early Warning Score 2 (NEWS2) score at admission. A total of 420 patients (172 East Asians and 248 South Asians) were included. The predictive model for intensive care unit (ICU) admission with variables NEWS2 Category II and higher, diabetes mellitus, liver dysfunction, and low lymphocyte counts had an area under the curve (AUC) value of 0.930 with a sensitivity of 0.931 and a specificity of 0.784. The predictive model for mortality with NEWS2 Category III, cancer, and decreasing lymphocyte count had an AUC value of 0.883 with a sensitivity of 0.903 and a specificity of 0.701. A combined predictive model with bronchial asthma and low lymphocyte count, in contrast, had an AUC value of 0.768 with a sensitivity of 0.828 and a specificity of 0.719 for NEWS2 score (5 or above) at presentation. NEWS2 supplemented with comorbidity profile and lymphocyte count could help identify hospitalized young adults at risk of adverse COVID-19 outcomes.

Covid-19-associated rhino-orbito-cerebral mucormycosis (CAROM) in Delhi: Demographics and risk factors in a single-centre consecutive cohort of 200 inpatients.

Background There was a dramatic rise in the incidence of rhino-orbito-cerebral mucormycosis associated with the 2021 Covid-19 wave in India. We aim to document the demographic characteristics and risk factors of a consecutive cohort of inpatients with Covid-19-associated rhino-orbito-cerebral mucormycosis (CAROM) during the surge of April-June 2021. Methods We included all patients of CAROM treated at our tertiary referral facility from 1 April to 14 June 2021. We prospectively gathered details with regard to Covid-19 illness and treatment, CAROM presentation, comorbid conditions and risk factors. Results Our prospective cohort consisted of 200 consecutive patients, of which 146 (73%) patients tested positive on the Covid-19 RT-PCR test at presentation. CAROM occurred concurrent with the Covid-19 infection in 86%, and delayed CAROM after seeming recovery from Covid-19 was seen in 14%. Covid-19 was classified as mild, moderate and severe in 54%, 33% and 13%. The surge of CAROM followed the population peak of Covid-19 infections by about 3 weeks. Advanced disease at presentation was frequent with ocular involvement in 56.6% (111/196) and central nervous system involvement in 20% (40/199). One or more comorbid conditions were identified in 191/200 (95.5%) patients. The dominant associations were with diabetes (189/200; 94.5%) and uncontrolled hyper-glycaemia (122/133; 91.7%), recent steroid use (114/ 200; 57%), which was often considered as inappropriate in dosage or duration, lymphopenia (142/176; 80.7%), and increased ferritin levels (140/160; 87.5%). No evidence supported the role of previous oxygen therapy or previous nasal swab testing as risk factors for CAROM. Conclusion The inpatient volumes of CAROM were noted to parallel the Covid-19 incidence curve by about 3 weeks. Covid-19 infection may directly predispose to CAROM by way of lymphopenia and increased ferritin levels. Uncontrolled hyperglycaemia is identified as a near-invariable association. Recent steroid use is noted as very frequent and was often received in excess of treatment advisories.

Visual Servoing Approach to Autonomous UAV Landing on a Moving Vehicle.

Many aerial robotic applications require the ability to land on moving platforms, such as delivery trucks and marine research boats. We present a method to autonomously land an Unmanned Aerial Vehicle on a moving vehicle. A visual servoing controller approaches the ground vehicle using velocity commands calculated directly in image space. The control laws generate velocity commands in all three dimensions, eliminating the need for a separate height controller. The method has shown the ability to approach and land on the moving deck in simulation, indoor and outdoor environments, and compared to the other available methods, it has provided the fastest landing approach. Unlike many existing methods for landing on fast-moving platforms, this method does not rely on additional external setups, such as RTK, motion capture system, ground station, offboard processing, or communication with the vehicle, and it requires only the minimal set of hardware and localization sensors. The videos and source codes are also provided.

Deep Learning-Based Spermatogenic Staging Assessment for Hematoxylin and Eosin-Stained Sections of Rat Testes.

In preclinical toxicology studies, a "stage-aware" histopathological evaluation of testes is recognized as the most sensitive method to detect effects on spermatogenesis. A stage-aware evaluation requires the pathologist to be able to identify the different stages of the spermatogenic cycle. Classically, this evaluation has been performed using periodic acid-Schiff (PAS)-stained sections to visualize the morphology of the developing spermatid acrosome, but due to the complexity of the rat spermatogenic cycle and the subtlety of the criteria used to distinguish between the 14 stages of the cycle, staging of tubules is not only time consuming but also requires specialized training and practice to become competent. Using different criteria, based largely on the shape and movement of the elongating spermatids within the tubule and pooling some of the stages, it is possible to stage tubules using routine hematoxylin and eosin (H&E)-stained sections, thereby negating the need for a special PAS stain. These criteria have been used to develop an automated method to identify the stages of the rat spermatogenic cycle in digital images of H&E-stained Wistar rat testes. The algorithm identifies the spermatogenic stage of each tubule, thereby allowing the pathologist to quickly evaluate the testis in a stage-aware manner and rapidly calculate the stage frequencies.

Gargle lavage & saliva: Feasible & cheaper alternatives to nasal & throat swabs for diagnosis of COVID-19.

Background & objectives: In the present scenario, the most common sample for diagnosis of COVID-19 by reverse transcription polymerase chain reaction (RT-PCR) is nasal and throat swab (NTS). Other sampling options such as gargle lavage have found limited application in clinical use mostly because of unavailability of an appropriate gargling liquid. This study was conducted to assess the stability of SARS-CoV-2 RNA in normal saline at 4°C that can serve as a gargling liquid as well as a transport medium. The study also looked at the agreement between NTS and gargle lavage/saliva for the detection of SARS-CoV-2. Methods: In 29 consecutive real-time RT-PCR (rRT-PCR) positive COVID-19 patients, paired NTS, gargle and saliva samples were taken. Samples were processed by rRT-PCR for the detection of SARS-CoV-2 RNA. To assess the SARS-CoV-2 RNA stability in normal saline, gargle lavage specimens were divided into two aliquots; one subset of the specimen was run within 4-6 h along with the routine samples (NTS and saliva) and the other subset was stored at 4°C and processed after 24-30 h. Agreement between cycle threshold (Ct) values from both the runs was compared using Bland-Altman (BA) analysis. Results: The positivity rates of rRT-PCR in NTS, saliva and gargle lavage samples were 82.7 (24/29), 79.3 (23/29) and 86.2 per cent (25/29), respectively. BA plot showed a good agreement between the Ct values of fresh and stored gargle samples, stipulating that there were no significant differences in the approximate viral load levels between the fresh and stored gargle lavage samples (bias: E gene -0.64, N gene -0.51, ORF gene -0.19). Interpretation & conclusions: Our study results show stability of SARS-CoV-2 RNA in the gargle samples collected using normal saline up to 24-30 h. Gargle lavage and saliva specimen collection are cost-effective and acceptable methods of sampling for the detection of SARS-CoV-2 RNA by rRT-PCR. These simplified, inexpensive and acceptable methods of specimen collection would reduce the cost and workload on healthcare workers for sample collection.

Delayed Referral for Adult Traumatic Brachial Plexus Injuries.

PURPOSE: The treatment of traumatic brachial plexus injury (BPI) is time-sensitive, and early nerve reconstruction is associated with superior nerve recovery. The objective of this study was to determine the rate of delayed referral to our centers for traumatic BPI, identifiable causes of delayed referral, and factors associated with delayed referral to a brachial plexus surgeon. METHODS: We identified 84 patients with traumatic BPI referred to and evaluated by brachial plexus surgeons at 2 tertiary care referral centers from 2015 to 2019. Delayed referral was defined as more than 3 months from the date of injury to the date of initial evaluation by a brachial plexus surgeon. Causes of delayed referral were identified by review of the medical record. Bivariate analysis and multivariable logistic regression were used to identify factors associated with delayed referral. RESULTS: Mean age of the 84 patients in the study was 45 years; 69% were male. The most common pattern of BPI was global palsy (39%), followed by upper-trunk palsy (23%) and infraclavicular palsy (15%). Median time from injury to surgical evaluation was 2 months (interquartile range, 2-4 months). Thirty-seven patients had a delayed referral (44%). Multivariable logistic regression analysis showed that the hospital to which the patient was referred, Medicare insurance, and motorcycle accident as the mechanism of injury were associated with a delayed referral. CONCLUSIONS: Nearly half of traumatic BPI patients evaluated at 2 tertiary referral centers in a large metropolitan area in the United States presented in a delayed time frame. Both modifiable and nonmodifiable associations with delayed referral were identified. Patients with Medicare insurance had increased odds of delayed referral. CLINICAL RELEVANCE: Establishment of multidisciplinary BPI specialty centers, outreach to local and regional hospitals, and development of referral algorithms and pathways may improve timeliness of referrals.

Impact of COVID-19 pandemic on bariatric surgery in India: An obesity and metabolic surgery society of India survey of 1307 patients.

BACKGROUND: Although safe practice guidelines were issued by the Obesity and Metabolic Surgery Society of India (OSSI) in the end of May 2020, surgeons have been in a dilemma about risk of subjecting patients to hospitalisation and bariatric surgery. This survey was conducted with the objective to evaluate the risk of coronavirus disease-19 (COVID-19) infection in peri- and post-operative period after bariatric and metabolic surgery (BMS). METHODS: A survey with OSSI members was conducted from 20 July 2020 to 31 August 2020 in accordance with EQUATOR guidelines. Google Form was circulated to all surgeon members through E-mail and WhatsAppTM. In the second phase, clinical details were captured from surgeons who reported positive cases. RESULTS: One thousand three hundred and seven BMS were reported from 1 January 2020 to 15 July 2020. Seventy-eight per cent were performed prior to 31 March 2020 and 276 were performed after 1 April 2020. Of these, 13 (0.99%) patients were reported positive for COVID-19 in the post-operative period. All suffered from a mild disease and there was no mortality. Eighty-seven positive cases were reported from patients who underwent BMS prior to 31 December 2019. Of these, 82.7% of patients had mild disease, 13.7% of patients had moderate symptoms and four patients succumbed to COVID-19. CONCLUSION: BMS may be considered as a safe treatment option for patients suffering from clinically severe obesity during the COVID-19 pandemic. Due care must be taken to protect patients and healthcare workers and all procedures must be conducted in line with the safe practice guidelines.

What Factors Are Associated With Response Rates for Long-term Follow-up Questionnaire Studies in Hand Surgery?

BACKGROUND: Long-term follow-up studies are an important tool in the evaluation of orthopaedic illness and its treatment options. However, a patient's participation in a follow-up study may be affected by several factors, leading to variability in response rates and the risk of selection bias. QUESTIONS/PURPOSES: (1) What is the average response rate in hand surgery questionnaire studies? (2) What factors are associated with higher and lower response rates to research questionnaires? (3) What factors are associated with higher and lower contact, initial participation, and completion rates? METHODS: We included 798 adult patients who were enrolled in one of 12 questionnaire follow-up studies in the hand and upper extremity service of our institution. All included studies evaluated patient-reported outcomes for the surgical treatment of upper extremity conditions using questionnaires and all used the same enrollment design. Patients were invited by letter to ask if they would be willing to participate, and we informed them that they would be contacted by telephone at least three times if they did not respond to the letter. Patients were contacted at a median of 6.6 years (interquartile range [IQR] 3.7 to 11) after surgery. The successful response rate was 49% (390 of 798 patients). We manually reviewed records to collect data on patient characteristics, and we performed bivariate analysis and multivariable logistic regression analysis to identify factors associated with the contact rate (percentage of patients reached by either mail, phone, or email), initial response rate (percentage of reached patients who initiated participation), completion rate (percentage of patients who initiated participation and completed the entire follow-up questionnaire), and our primary outcome successful response rate (percentage of patients who were contacted and who completed the entire questionnaire). RESULTS: The average response rate in hand surgery questionnaire studies was 49% (390 of 798 patients). In the multivariable analysis, enrollment of women (odds ratio 1.43 [95% confidence interval 1.03 to 1.97]; p = 0.031) was independently associated with higher response rates. On the contrary, a longer follow-up time from surgery (OR 0.95; 95% CI 0.92 to 0.99]; p = 0.015) and multiple researchers contacting patients (OR 0.51 [95% CI 0.37 to 0.71]; p < 0.001) were independently associated with lower response rates. The contact rate was higher for women (OR 1.46 [95% CI 1.03 to 2.06]; p = 0.034) and patients with higher income (OR 1.000007 [95% CI 1.000001 to 1.000013]; p = 0.019). The contact rate was lower in patients with a longer follow-up time from surgery (OR 0.93 [95% CI 0.90 to 0.97]; p = 0.001). The initial participation rate was lower when patients were contacted by multiple researchers (OR: 0.34 [95% CI 0.23 to 0.52]; p < 0.001). Studies with a lower number of questions (36; IQR 22 to 46) were completed more frequently than studies with a higher number of questions (51; IQR 39 to 67; p = 0.044). CONCLUSIONS: Studies assessing long-term outcomes that have a large proportion of men and longer follow-up time tend to have lower response rates. When performing a follow-up study, it seems beneficial to have one researcher contact the patients and use a shorter questionnaire. Results of this study can help clarify the response rates in hand surgery follow-up questionnaire studies and help with the planning of future follow-up studies. LEVEL OF EVIDENCE: Level II, prognostic study.

Factors Associated With Reoperation and Conversion to Wrist Fusion After Proximal Row Carpectomy or 4-Corner Arthrodesis.

PURPOSE: Proximal row carpectomy (PRC) and 4-corner arthrodesis (FCA) are common salvage procedures for the treatment of scapholunate advanced collapse and scaphoid nonunion advanced collapse. This study aimed to assess rates of reoperation and conversion to wrist fusion and to assess the factors associated with reoperation and conversion to wrist fusion for patients treated with PRC and FCA. METHODS: A retrospective chart review was performed evaluating 266 adult patients undergoing PRC or FCA at a single institutional system from 2002 to 2016. Demographic data, patient- and injury-specific data, reoperation and conversion rates, and complications were collected. Potential factors associated with reoperation or wrist fusion were evaluated using a bivariate, followed by a multivariable, analysis. RESULTS: Reoperation was more commonly performed in FCA (34%) than in PRC (11%) (odds ratio [OR], 3.4; 95% confidence interval [95% CI], 1.7-6.8) and occurred at a shorter postoperative interval. In a multivariable analysis for reoperation, manual labor was associated with reoperation in patients undergoing FCA (OR, 5.4; 95% CI, 1.5-19.1). In those undergoing PRC, anterior interosseous nerve (AIN) and/or posterior interosseous nerve (PIN) neurectomy was associated with a lower rate of reoperation (OR, 0.18; 95% CI, 0.06-0.57). In a multivariable analysis for conversion to wrist arthrodesis, intraoperative AIN and/or PIN neurectomy (OR, 0.18; 95% CI, 0.06-0.57) was associated with a lower rate of conversion to wrist fusion, and smoking (OR, 4.9; 95% CI, 1.8-13.5) was associated with a higher rate of conversion to wrist fusion. In the subanalysis of patients who underwent PRC, only AIN and/or PIN neurectomy was associated with lower rates of conversion to wrist arthrodesis (OR, 0.15; 95% CI, 0.04-0.56). CONCLUSIONS: In our cohort, we observed that AIN and/or PIN neurectomy reduced the risk of reoperation and conversion to wrist arthrodesis after PRC. Smoking increased the odds of conversion to wrist arthrodesis in the combined PRC/FCA cohort; however, it is unclear whether this was due to smoking itself or whether the indications for PRC or FCA were affected, leading to this result. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.

Spontaneous Bilateral Subdural Hematoma in a Patient with Falciparum Malaria.

A 70-year old female presented with complaints of fever with chills, headache for 15 days and altered sensorium for 7 days. Peripheral blood smear showed ring form of P. falciparum and CT brain revealed bilateral subdural hematoma. Patient received Artesunate based combination therapy and recovered completely without surgical intervention within 8 days of admission.

Upper Extremity Tendon Transfers: A Brief Review of History, Common Applications, and Technical Tips.

Background Tendon transfer in the upper extremity represents a powerful tool in the armamentarium of a reconstructive surgeon in the setting of irreparable nerve injury or the anatomic loss of key portions of the muscle-tendon unit. The concept uses the redundancy/expendability of tendons by utilizing a nonessential tendon to restore the function of a lost or nonfunctional muscle-tendon unit of the upper extremity. This article does not aim to perform a comprehensive review of tendon transfers. Instead it is meant to familiarize the reader with salient historical features, common applications in the upper limb, and provide the reader with some technical tips, which may facilitate a successful tendon transfer. Learning Objectives (1) Familiarize the reader with some aspects of tendon transfer history. (2) Identify principles of tendon transfers. (3) Identify important preoperative considerations. (4) Understand the physiology of the muscle-tendon unit and the Blix curve. (5) Identify strategies for setting tension during a tendon transfer and rehabilitation strategies. Design This study was designed to review the relevant current literature and provide an expert opinion. Conclusions Tendon transfers have evolved from polio to tetraplegia to war and represent an extremely powerful technique to correct neurologic and musculotendinous deficits in a variety of patients affected by trauma, peripheral nerve palsies, cerebral palsy, stroke, and inflammatory arthritis. In the contemporary setting, these very same principles have also been very successfully applied to vascularized composite allotransplantation in the upper limb.

Prevalence of substance use disorders in Punjab: Findings from National Mental Health Survey.

Background & objectives: Substance use disorders are a major public health concern in Punjab. However, reliable estimates of prevalence of substance use disorders are not available for the State. The present study reports estimates of prevalence of substance use disorders in Punjab, conducted as part of National Mental Health Survey, India. Methods: Using multistage stratified random cluster sampling, 2895 individuals from 719 households of 60 clusters (from 4 districts of Punjab) were interviewed. Mini International Neuropsychiatric Interview and Fagerstrom nicotine dependence scale were used to assess substance use disorders. Results: The sample comprised almost equal numbers of males and females. Nearly 80 per cent had less than or equal to high school education, and 70 per cent were married. The weighted prevalence of alcohol and other substance use disorders was 7.9 and 2.48 per cent, respectively. The prevalence of tobacco dependence was 5.5 per cent; 35 per cent households had one person with substance use disorder. The prevalence was highest in the productive age group (30-39 yr), urban metro and less educated persons. The prevalence of alcohol and other substance use disorders was much higher in Punjab as compared to other States where survey was done. Tobacco dependence was lowest in Punjab. Majority (87%) of the persons with substance use disorders did not suffer from any other mental disorder. Treatment gap was 80 per cent. Interpretation & conclusions: Punjab has a high burden of substance use disorders. The estimates will help clinicians and policymakers to plan the strategies against the menace of substance use disorders effectively.

Development of Targeted Muscle Reinnervation Model in Hind Limb Amputated Rats.

BACKGROUND: Targeted muscle reinnervation (TMR) is a novel approach to postamputation neuroma pain; however, this has not been explicitly studied. The purpose of this study was to develop a TMR model in hind limb amputated rats. METHODS: Ten hind limbs from 5 Sprague Dawley cadaver rats were used. Sciatic nerve, main branches of the sciatic nerve (common peroneal, tibial, sural), motor branches from the sciatic nerve to the biceps femoris and cauda femoris, gluteal nerve and its motor branches to the semimembranosus, and biceps femoris and femoral nerve were dissected to look for consistent nerve anatomy that can be used for TMR in the rat hind limb amputation model. Transfemoral amputation was performed and two types of coaptations were made: common peroneal nerve to motor branch to biceps femoris and tibial nerve to motor branch to semimembranosus. RESULTS: The total surgical time for the dissection, amputation, and coaptation of nerves was ∼90 minutes. A total of 100 nerves were dissected in 10 rat hind limbs. Anatomical dissections were straightforward to perform. Anatomy of the dissected nerves was consistent. Hind limb amputations were performed without damaging the target muscles and nerves. Nerve lengths were sufficient for coaptation without any tension. CONCLUSIONS: To the best of our knowledge, this is the first report on TMR model in hind limb amputated rats. This model will allow for mechanical, electromyography (EMG), and histological analysis for future assessment of neuroma prevention.

A systematic review of outcomes reporting for brachial plexus reconstruction.

PURPOSE: To better understand the manner in which outcomes are reported after brachial plexus reconstruction, we conducted a systematic review of the scientific literature. METHODS: We included English-language articles describing treatment of brachial plexus injuries to restore motor function of the shoulder, elbow, forearm, and/or wrist with nerve repair, nerve graft, and/or nerve transfer. We recorded the anatomical location of injury, the treatment used, and the manner in which motor function, active and passive range of motion, pain, quality of life, function or disability, patient satisfaction, and psychosocial health was reported. RESULTS: In reviewing 88 papers with outcomes for 5,189 patients, 83 (94%) of the papers reported postoperative motor function. Of these, 49 (59%) did not include any other measures of patient outcome. Active range of motion was reported in 24 (27%) studies, pain was reported in 15 (17%) studies, quality of life was reported in 4 (5%) studies, function or disability was reported in 5 (6%) studies, patient satisfaction in 3 (3%) studies, and psychosocial health in 1 study. CONCLUSIONS: To date, outcome reporting for brachial plexus surgery has largely centered on motor recovery and typically has not included measures of function or nonmusculoskeletal recovery. Incorporating currently used measures of physical recovery with patient-derived outcomes measures such as quality of life, function, pain, and satisfaction will likely help provide a more comprehensive understanding of the effect of brachial plexus reconstruction surgery. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic III.

Surgical Treatments for Scapholunate Advanced Collapse Wrist: Kinematics and Functional Performance.

PURPOSE: The purpose of this investigation was to compare kinematic motion and functional performance during 2 tasks in patients following 4-corner fusion (4CF) or proximal row carpectomy (PRC) and to compare these data with those from healthy asymptomatic individuals. METHODS: Twenty men (10 4CFs and 10 PRCs, ages, 43-82 y) were recruited for 3-dimensional wrist motion analysis testing. Kinematic coupling (the ratio of wrist flexion/extension to radial-ulnar deviation), kinematic path length (a measure of total angle distance), clinical measures, and performance measures were collected during 2 tasks: dart throwing and hammering. For each outcome, between-group comparisons employed a 1-way analysis of variance with post hoc analysis using the Fisher least significant difference test. RESULTS: All clinical measures (flexion-extension, radial-ulnar deviation, and grip strength) were decreased for 4CF and PRC patients compared with healthy subjects. Coupling, kinematic path length, and performance were all significantly reduced in 4CF and PRC patients compared with healthy subjects during both tasks. Reduced coupling and a shorter kinematic path length are indicative of less global and combined wrist motion. There were no differences identified in coupling patterns or performance between the surgical groups for the dart-throwing task. However, in hammering, the kinematic path length and performance (time and total strikes) were worse in 4CF than in PRC. CONCLUSIONS: Differences in wrist kinematics and performance were identified between the groups. PRC subjects performed better on kinematic and performance variables. As expected, both groups demonstrated decreased wrist kinematic motion and functional performance compared with individuals with normal wrists. These results require confirmation and while they cannot be used to determine the benefits of one procedure over the other, they are an important step in quantifying differences in motion and function between procedures. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic II.

The effect of topical anesthetic hydration on the depth of thermal injury from the plasma skin regeneration device.

BACKGROUND AND OBJECTIVES: The plasma skin regeneration (PSR) device delivers thermal energy to the skin by converting nitrogen gas to plasma. Prior to treatment, hydration of the skin is recommended as it is thought to limit the zone of thermal damage. However, there is limited data on optimal hydration time. This pilot study aims to determine the effect of topical anesthetic application time on the depth of thermal injury from a PSR device using histology. STUDY DESIGN/MATERIALS AND METHODS: PSR (1.8 and 3.5 J) was performed after 0, 30, or 60 minutes of topical anesthetic application. Rhytidectomy was then performed and skin was fixed for histologic analysis. Four patients (two control and four treatment sites per patient) undergoing rhytidectomy were recruited for the study. Each patient served as his/her own control (no hydration). A scoring system for tissue injury was developed. Epidermal injury, the presence of vacuolization, blistering, damage to adnexal structures, and depth of dermal collagen changes were evaluated in over 1,400 high-power microscopy fields. RESULTS: There was a significant difference in the average thermal injury score, depth of thermal damage, and epidermal injury when comparing controls to 30 minutes of hydration (P = 0.012, 0.012, 0.017, respectively). There was no statistical difference between controls and 60 minutes of hydration or between 30 and 60 minutes of hydration. Epidermal vacuolization at low energy and patchy distribution of thermal injury was also observed. CONCLUSION: Topical hydration influences the amount of thermal damage when applied to skin for 30 minutes prior to treatment with the PSR device. There was a trend toward decreasing thermal damage at 60 minutes, and there was no difference between treatment for 30 or 60 minutes. The data suggest that application of topical anesthetic for a short period of time prior to treatment with the PSR device is cost-effective, safe, and may be clinically beneficial.

Nasopharyngeal acid reflux and Eustachian tube dysfunction in adults.

OBJECTIVE: This study aimed to evaluate the relationship between nasopharyngeal pH and Eustachian tube dysfunction (ETD) in adults. STUDY DESIGN: Unmatched case-control study. METHODS: Forty-one subjects, 20 adults with a diagnosis of ETD and 21 healthy adults as controls, were enrolled from an outpatient clinic. All subjects had a Dx-pH probe placed near the torus tubarius in the posterior nasopharynx for 24 hours. The pH values were recorded every 0.5 second. Decreases in pH were considered as reflux events if the pH dropped below 5.5. RESULTS: The average nasopharyngeal pH value was 6.90 (range, 5.33-7.73) in the subjects with ETD and 7.07 (range, 5.99-7.94) in the controls. The difference between the 2 groups was not statistically significant (P = .30). The ETD group, on average, had a higher number of nasopharyngeal reflux events (2.3 +/- 1.6 vs 0.8 +/- 1.2, respectively; P = .002) and higher reflux finding score (3.6 +/- 2.7 vs 0.4 +/- 1.4, respectively; P < .00 I) than the control group. CONCLUSION: By using a novel pH probe that allows detection of acidity in a nonliquid environment, a comparison of nasopharyngeal pH between control patients and those with ETD was performed. Eustachian tube dysfunction was more likely to be associated with a higher number of nasopharyngeal reflux events and higher reflux finding score. Nasopharyngeal reflux may have a role in the pathogenesis of ETD.

Wrist kinematic coupling and performance during functional tasks: effects of constrained motion.

PURPOSE: To quantify the coupled motion of the wrist during selected functional tasks and to determine the effects of constraining this coupled motion using a radial-ulnar deviation blocking splint on performance of these tasks. METHODS: Ten healthy, right-handed men performed 15 trials during selected functional tasks with and without a splint, blocking radial and ulnar deviation. The following tasks were performed: dart throwing, hammering, basketball free-throw, overhand baseball and football throwing, clubbing, and pouring. Kinematic coupling parameters (coupling, kinematic path length, flexion-extension range of motion, radial-ulnar deviation range of motion, flexion-extension offset, and radial-ulnar deviation offset) and performance were determined for each functional task. A generalized estimation equation model was used to determine whether each kinematic coupling parameter was significantly different across tasks. A repeated-measures generalized estimation equation model was used to test for differences in performance and kinematic coupling parameters between the free and splinted conditions. RESULTS: Wrist motion exhibited linear coupling between flexion-extension and radial-ulnar deviation, demonstrated by R(2) values from 0.70 to 0.99. Average wrist coupling and kinematic path lengths were significantly different among tasks. Coupling means and kinematic path lengths were different between free and splinted conditions across all tasks other than pouring. Performance was different between wrist conditions for dart throwing, hammering, basketball shooting, and pouring. CONCLUSIONS: Wrist kinematic coupling parameters are task specific in healthy individuals. Functional performance is decreased when wrist coupling is constrained by an external splint. CLINICAL RELEVANCE: Surgical procedures that restrict wrist coupling may have a detrimental effect on functional performance as defined in the study. Patients may benefit from surgical reconstructive procedures and wrist rehabilitation protocols designed to restore kinematic coupling.