Barriers to Remote Burn Care Delivery: An Analysis of Burn Center Proximity and Access to Critical Telehealth Infrastructure.

ABSTRACT: Mounting evidence supports the use of telehealth to improve burn care access and efficiency. However, barriers to telehealth use remain throughout the United States and may disproportionately affect specific populations, such as rural and non-English-speaking patients. This study analyzes the association between physical proximity to burn care and determinants of telehealth access.The relationship between telehealth-associated measures and proximity to burn care was analyzed with linear regression analysis. County-level data was sourced from the Agency for Healthcare Research and Quality's Social Determinants of Health Database (2020) and the American Community Survey (2021). County-level distances to the nearest American Burn Association (ABA)-verified burn center were calculated based on verified centers listed in the ABA burn center directory (n = 59). A subsequent analysis was performed on income-stratified datasets available for subset counties.Distance was negatively correlated with access to a smartphone (P < 0.0001), broadband internet (P < 0.0001), and cellular data plan (P < 0.0001) and positively correlated with the percent of households with no computing device (P < 0.0001) and no internet access (P < 0.0001). Analysis of income-stratified data revealed similar results. The percent population not speaking English well (P < 0.0001) at all (P = 0.0009) and the proportion of limited English-speaking households (P = 0.0001) decreased as a function of distance.People living furthest from an ABA-verified burn center in the United States are less likely to have adequate access to critical telehealth infrastructure compared to their counterparts living closer to a burn center. However, income impacts overall access and the degree to which access changes with proximity. Conversely, language-associated barriers decrease as distance increases.

The multidirectional roles of the anterior oblique ligament and dorsoradial ligament of the thumb carpometacarpal joint.

The multidirectional biomechanics of the thumb carpometacarpal (CMC) joint underlie the remarkable power and precision of the thumb. Because of the unconfined nature of thumb CMC articulation, these biomechanics are largely dictated by ligaments, notably the anterior oblique ligament (AOL) and the dorsoradial ligament (DRL). However, the rotational and translational stabilizing roles of these ligaments remain unclear, as evidenced by the variety of interventions employed to treat altered pathological CMC biomechanics. The purpose of this study was to determine the effects of sectioning the AOL (n = 8) or DRL (n = 8) on thumb CMC joint biomechanics (rotational range-of-motion [ROM] and stiffness, translational ROM) in 26 rotational directions, including internal and external rotation, and in eight translational directions. Using a robotic musculoskeletal simulation system, the first metacarpal of each specimen (n = 16) was rotated and translated with respect to the trapezium to determine biomechanics before and after ligament sectioning. We observed the greatest increase in rotational ROM and decrease in rotational stiffness in flexion directions and internal rotation following DRL transection and in extension directions following AOL transection. The greatest increase in translational ROM was in dorsal and radial directions following DRL transection and in volar directions following AOL transection. These data suggest the AOL and DRL play complementary stabilizing roles, primarily restraining translations in the direction of and rotations away from the ligament insertion sites. These findings may inform future interventions or implant designs for pathological CMC joints.

An analysis of urodynamic parameters in diabetic and nondiabetic women.

OBJECTIVES: Diabetes is highly prevalent worldwide, with an estimated 536 million living with diabetes in 2021, and that number projected to increase to 783 million by 2045. Diabetic bladder dysfunction is thought to affect up to 60%-90% of individuals with diabetes and can significantly impact quality of life. Despite the prevalence of diabetic bladder dysfunction, the exact pathophysiological mechanism, and resulting clinical presentation, remains debated. Our objective was to compare urodynamic parameters between diabetic and nondiabetic women, assessing the impact of various markers of diabetes severity on bladder function. METHODS: A retrospective chart review was conducted on female patients aged 18 and above who underwent urodynamic studies at a single tertiary care university hospital system from 2014 to 2020. Patients were categorized based on diabetes status, and diabetes severity including duration of disease, hemoglobin A1c levels, insulin dependence, and markers of end-organ dysfunction. Urodynamic variables, including compliance, bladder voided efficiency, bladder contractility index, postvoid residual, maximum flow rate, capacity, voided volume, and detrusor overactivity, were assessed by two independent reviewers. Statistical analyses were performed to assess the impact of diabetes and diabetic severity on urodynamic parameters. RESULTS: A total of 652 female patients were included in the study, of which, 152 (23.3%) had diabetes, with an average duration of diagnosis of 82.3 months. Diabetic women were older and had higher body mass index compared to nondiabetic women. Diabetic retinopathy and neuropathy were present in 18% and 54.6% of diabetic patients, respectively. Significant differences in urodynamic parameters were observed between diabetic and nondiabetic women, with diabetic women showing higher rates of detrusor overactivity (p = 0.01), particularly associated with increasing BMI (p = 0.03). However, classic markers of diabetes severity including duration, as well as markers of end-organ damage, showed mixed associations with urodynamic changes. CONCLUSIONS: Despite the prevalence of diabetic bladder dysfunction and its impact on patient quality of life, the exact mechanisms and clinical presentation remain elusive. Our study highlights the significant differences in urodynamic parameters between diabetic and nondiabetic women, emphasizing the need for further research into the relationship between diabetes and diabetic bladder dysfunction.

Long-term Renal Preservation and Complication Profile With Ileal Ureter Creation.

OBJECTIVE: To examine long-term ileal ureter replacement results at over 32 years at our institution. Long segment or proximal ureteral strictures pose a challenging reconstructive problem. Ureteroureterostomy, psoas hitch, Boari flap, buccal ureteroplasty, and autotransplantation are common reconstructive techniques. We show that ileal ureter remains a lasting option. METHODS: We performed a retrospective review of patients undergoing open ileal ureter creation from 1989-2021. Patient demographics, operative history, and complications were examined. All patients were followed for changes in renal function. Demographic data were analyzed and Cox proportional hazard models were performed. RESULTS: One hundred and fifty-eight patients were identified with median follow-up time of 40 months. Eighty-one percent had a unilateral ileal ureter creation. Fifty percent were female, median age was 53.3. Twenty-seven percent of patients had radiation-induced strictures. Preoperatively, 56.3% of patients were chronic kidney disease stage 1-2 and 43.7% were stage 3-5. Post-operatively, 54% were stage 1-2 and 46% were stage 3-5. Cox proportional hazard models demonstrated no significant correlation between worsening renal function and stricture cause, bilateral repair, complications, or sex (biologically male or female). Seventy-seven percent had no 30-day complications. Clavien complications included grade 1 (18), grade 2 (4), grade 3 (9), and grade 4 (5). Long-term complications included worsening renal function (3%), incisional hernia (8.2%), and small bowel obstruction (6.9%). Five (3.1%) patients ultimately required dialysis and 5 (3.1%) patients developed metabolic acidosis. CONCLUSION: Ileal ureteral reconstruction is often a last resort for patients with complex ureteral injuries. Clinicians can be reassured by our long-term data that ileal ureteral creation is a safe treatment with good preservation of renal function and low risk of hemodialysis and metabolic acidosis.

A review of wear debris in thumb base joint implants.

AIM: Polymers and metals, such as polyethylene (PE) and cobalt chrome (CoCr), are common materials used in thumb-based joint implants, also known as CMC (Carpometacarpal) arthroplasty. The purpose of this review was to investigate the reported failure modes related to wear debris from these type of materials in CMC implants. The impact of wear debris on clinical outcomes of CMC implants was also examined. Potential adverse wear conditions and inflammatory particle characteristics were also considered. METHOD: A literature search was performed using PRISMA guidelines and 55 studies were reviewed including 49 cohort studies and 6 case studies. Of the 55 studies, 38/55 (69%) focused on metal-on-polyethylene devices, followed by metal-on-metal (35%), and metal-on-bone (4%). RESULTS: The summarized data was used to determine the frequency of failure modes potentially related to wear debris from metals and/or polymers. The most commonly reported incidents potentially relating to debris were implant loosening (7.1%), osteolysis (1.2%) and metallosis (0.6%). Interestingly the reported mechanisms behind osteolysis and loosening greatly varied. Inflammatory reactions, while rare, were generally attributed to metallic debris from metal-on-metal devices. Mechanisms of adverse wear conditions included implant malpositioning, over-tensioning, high loading for active patients, third-body debris, and polyethylene wear-through. No specific examination of debris particle characterization was found, pointing to a gap in the literature. CONCLUSION: This review underscores the types of failure modes associated with wear debris in CMC implants. It was found that failure rates and adverse wear conditions of CMC implants of any design are low and the exact relationship between wear debris and implant incidences, such as osteolysis and loosening remains uncertain. The authors note that further research and specific characterization is required to understand the relationship between debris and implant failure.

Access to Certified Burn Centers in the United States: The Geospatial and Transport Cost of Transfer.

Specialized burn centers are critical to minimizing burn-associated morbidity and mortality. However, American Burn Association-verified burn centers are unequally distributed across the United States, and fewer centers are available for pediatric patients relative to adults. The economic burden of transporting patients to these centers contributes significantly to the high cost of burn care. This study quantifies inequitable burn care access in the contiguous United States due to age group and location as a function of physical proximity to a verified burn center and transportation cost. County-level distances to the nearest verified adult or pediatric burn center were determined and mapped. Distance calculations for each population were combined with transport cost data (2022 CMS Ambulance Fee Schedules) to estimate transportation costs for each population (adult vs pediatric, urban vs rural). Pediatric patients reside 30.5 miles further than adults from the nearest center, significantly increasing transportation costs. Ground and air transport costs also increased for rural versus urban patients. Notably, rural patients face almost double the cost of air transport. While physical proximity to burn care appears to differ only modestly across age and region, this marginal increase in distance is associated with significant economic impact. This study highlights physical and economic barriers to burn care access faced by rural and pediatric patients and underscores the critical need to improve equity in burn care access. Future studies should expand on this report's findings to more fully characterize the additional costs associated with inequitable burn care access.

Are Gluon Showers inside a Quark-Gluon Plasma Strongly Coupled? A Theorist's Test.

We study whether in-medium showers of high-energy gluons can be treated as a sequence of individual splitting processes g→gg, or whether there is significant quantum overlap between where one splitting ends and the next begins. Accounting for the Landau-Pomeranchuk-Migdal (LPM) effect, we calculate such overlap effects to leading order in high-energy α_{s}(µ) for the simplest theoretical situation. We investigate a measure of overlap effects that is independent of physics that can be absorbed into an effective value q[over ^]_{eff} of the jet-quenching parameter q[over ^].

Proximal Interphalangeal Joint Arthroplasty for Fracture.

Proximal interphalangeal joint arthroplasties can be performed in the setting of acute comminuted fracture, chronic fracture presentations, and posttraumatic arthritis. These surgeries provide excellent pain relief and patient satisfaction but patients should be cautioned not to expect an improvement in motion postoperatively. Despite high rates of minor complications and radiographic loosening, these implants have good rates of long-term survival with most revisions occurring in the early postoperative period. They provide viable alternatives to arthrodesis, osteotomy and amputation in the appropriate patient.

Surgical management of acquired buried penis and scrotal lymphedema: A retrospective review.

Acquired buried penis is a condition that can have detrimental physical and psychological consequences for patients. Factors such as elevated BMI, chronic scrotal lymphedema, hidradenitis suppurativa, and chronic inflammation can lead to the condition. Surgical intervention is the treatment of choice for advanced disease. Following IRB approval, a retrospective chart review was performed for patients with a diagnosis of acquired buried penis who required surgical intervention. Details of patient history, surgical management including intraoperative and post-operative photography, and complications were reviewed. Seven patient cases were reviewed. The average age at time of surgery was 44 with a mean weight of 344 pounds and an average BMI of 48. Severe scrotal lymphedema and hidradenitis were common concurrent comorbidities. Concurrent scrotoplasty and infraumbilical panniculectomy were standard parts of the operations. Native glans skin was salvageable in all but one case. Penile shaft skin was reconstructed with skin grafts or adjacent tissue transfer. 88% of the cases had some element of wound dehiscence post-operatively. Surgical management of an acquired buried penis can be challenging. The patient demographic with the disease is frequently complicated by morbid obesity, concurrent lymphedema, or hidradenitis. Post-operative complications are expected. The surgical techniques presented can aid in simplifying the management of this challenging surgical population.

Comparison of inferior gluteal artery perforator flaps versus vertical rectus abdominis musculocutaneous flaps in the reconstruction of perineal wounds.

BACKGROUND: Achieving a healed perineal wound following chemoradiotherapy and abdominoperineal resection (APR) is challenging for surgeons and patients. Prior studies have shown trunk-based flaps, including vertical rectus abdominis myocutaneous (VRAM) flaps, are superior to both primary closure and thigh-based flaps; however, there has been no direct comparison with gluteal fasciocutaneous flaps. This study evaluates postoperative complications after various methods of perineal flap closure of APR and pelvic exenteration defects. METHODS: Retrospective review of patients who underwent APR or pelvic exenteration from April 2008 through September 2020 was analyzed for postoperative complications. Flap closure techniques, including VRAM, unilateral (IGAP), and bilateral (BIGAP) inferior gluteal artery perforator fasciocutaneous flaps, were compared. RESULTS: Of 116 patients included, the majority underwent fasciocutaneous (BIGAP/IGAP) flap reconstruction (n = 69, 59.6%), followed by VRAM (n = 47, 40.5%). There were no significant differences between group patient demographics, comorbidities, body mass index, or cancer stage. There were no significant differences between BIGAP/IGAP and VRAM groups in minor complications (57% versus 49%, p = 0.426) or major complications (45% versus 36%, p = 0.351), including major/minor perineal wounds. CONCLUSIONS: Prior studies have shown flap closure is preferable to primary closure after APR and neoadjuvant radiation but lack consensus on which flap offers superior postoperative morbidity. This study comparing outcomes of perineal flap closure showed no significant difference in postoperative complications. Fasciocutaneous flaps are a viable choice for the reconstruction of these challenging defects.

Subdermal Plexus Density as It Relates to Obesity and Wound Complications in Patients Undergoing Reduction Mammaplasty.

Background: Reduction mammaplasty is one of the most common reconstructive procedures performed in plastic surgery. Multiple comorbidities play a role in postoperative wound healing complications; however, there are insufficient data on the subdermal plexus (SDP) as it relates to these comorbidities. The purpose of this study is to evaluate the relationship between body mass index (BMI) and SDP of the superficial breast tissues and examine the association between SDP and postoperative complications. Methods: After Institutional Review Board approval, screening, and informed consent, patients undergoing reduction mammaplasty were selected. Tissue to be discarded was sent to pathology for analysis of immunohistochemistry directed against endothelial cells to determine the density of the SDP. Patients with BMI <35 and ≥35 kg/m2 were compared. Statistical analysis, including 2-tailed t test and Pearson correlation, was conducted. Results: A significant difference in SDP density (standard deviation) was identified between patients with a BMI ≥35 versus <35 kg/m2 (2.65 capillaries/mm2 ± 1.8 vs 1.56 capillaries/mm2 ± 1.2; P = .033). Patients with no historical use of tobacco versus those who used tobacco showed a significantly increased SDP (2.11 capillaries/mm2 ± 1.6 vs 1.20 capillaries/mm2 ± 0.5; P = .009). A significant relationship between postoperative infection (1.00 capillaries/mm2 ± 1.1; P = .041) and hematoma/seroma (0.788 capillaries/mm2 ± 0.1; P = .003) was identified. No significant relationship was found between SDP and delayed wound healing, nipple-areolar complex complications, fat/flap necrosis, or symptomatic scar occurrence. Conclusions: There is a statistically significant increase in SDP seen with increasing BMI, which does not explain the higher rate of wound healing complications after reduction mammaplasty typically seen in the higher BMI patient population. The association between BMI and complications after reduction mammaplasty remains unclear.

Three-dimensional transesophageal echocardiographic evaluation of pulmonary vein anatomy prior to cryoablation: validation with cardiac CT scan.

BACKGROUND: Anatomical characteristics of the left atrium and the pulmonary veins (PVs) may be relevant to the success rate of cryoballoon (CB)-ablation for atrial fibrillation (AF). Cardiac computed tomography (CCT) is considered as the gold standard for preablation imaging. Recently, three-dimensional transesophageal echocardiography (3DTOE) has been proposed for preprocedural assessment of cardiac structures relevant to CB-ablation. The accuracy of 3DTOE has not been validated by other imaging modalities. OBJECTIVE: We prospectively evaluated the feasibility and the accuracy of 3DTOE imaging for the assessment of left atrial and PV structures prior to pulmonary vein isolation (PVI). In addition, CCT was used to validate the measurements obtained with 3DTOE. METHODS: PV anatomy of 67 patients (59.7% men, mean age 58.5 ± 10.5 years) was assessed using both 3DTOE and CCT scan prior to PVI with the Arctic Front CB. The following parameters were measured bilaterally: PV ostium area (OA), the major and minor axis diameters of the ostium (a > b) and the width of the carina between the superior and the inferior PVs. In addition, the width of the left lateral ridge (LLR) between the left atrial appendage and the left superior PV. Evaluation of inter-technique agreement was based on linear regression with Pearson correlation coefficient (PCC) and Bland-Altman analysis of biases and limits of agreement. RESULTS: Moderate positive correlation (PCC 0.5-0.7) was demonstrated between the two imaging methods for the right superior PV's OA and both axis diameters, the width of the LLR and left superior PV (LSPV) minor axis diameter (b) with limits of agreement ˂50% and no significant biases. Low positive or negligible correlation (PCC < 0.5) was found for both inferior PV parameters. CONCLUSIONS: Detailed assessment of the right superior PV parameters, LLR and LSPV b is feasible with 3DTOE prior to AF ablation. This 3DTOE measurements demonstrated a clinically acceptable inter-technique agreement with those obtained with CCT.

Ileal Ureter Utilization in Patients With Previous Urinary Diversions.

OBJECTIVE: To evaluate a subset of patients who develop strictures requiring Ileal Ureter (IU) in the setting of prior urinary diversion or augmentation (ileal conduits, neobladders, continent urinary diversions). To our knowledge, there are no prior studies on patients with IU substitution into established lower urinary tract reconstructions. METHODS: A retrospective review of patients (18 years) undergoing IU creation from 1989 to 2021 was performed. A total of 160 patients were identified. In total, 19 (12%) patients had IUs into diversions. We examined demographics, stricture cause, diversion type, renal function, and postoperative complications. RESULTS: Nineteen patients were identified. Sixteen were male. Mean age was 57.7(SD 17.0) years. Diversions included continent urinary reservoirs (4), neobladders (5), ileal conduits (7), and bladder augmentations with Monti channels (3). Fifteen had unilateral surgery, and 4 had bilateral "reverse 7" IU creation. Average length of stay was 7.6 days (SD 2.9). Average follow-up was 32.9 months (SD 27). Mean preoperative creatinine was 1.5 (SD 0.4); mean postoperative creatinine at most recent follow-up was 1.6 (SD 0.7). There was no significant difference between pre- and postoperative creatinine (P = .18). One patient had a ventriculoperitoneal Shunt infection resulting ventriculoperitoneal shunt externalization, 1 had Clostridium difficile infection potentially causing an entero-neobladder fistula, 2 with ileus, 1 urine leak, and 1 wound infection. None required renal replacement therapy. CONCLUSION: Patients with urinary diversions and prior bowel reconstructive surgeries with subsequent ureteral strictures are a challenging cohort of patients. In properly selected patients, ureteral reconstruction with ileum is feasible and preserves renal function with minimal long-term complications.

Dorsal Subluxation of the First Metacarpal During Thumb Flexion is an Indicator of Carpometacarpal Osteoarthritis Progression.

BACKGROUND: Measurable changes in patients with progression of thumb carpometacarpal (CMC) osteoarthritis (OA) include joint space narrowing, osteophyte formation, subluxation, and adjacent-tissue changes. Subluxation, an indication of mechanical instability, is postulated as an early biomechanical indicator of progressing CMC OA. Various radiographic views and hand postures have been proposed to best assess CMC subluxation, but 3D measurements derived from CT images serve as the optimal metric. However, we do not know which thumb pose yields subluxation that most indicates OA progression. QUESTIONS/PURPOSES: Using osteophyte volume as a quantitative measure of OA progression, we asked: (1) Does dorsal subluxation vary by thumb pose, time, and disease severity in patients with thumb CMC OA? (2) In which thumb pose(s) does dorsal subluxation most differentiate patients with stable CMC OA from those with progressing CMC OA? (3) In those poses, what values of dorsal subluxation indicate a high likelihood of CMC OA progression? METHODS: Between 2011 and 2014, 743 patients were seen at our institutions for trapeziometacarpal pain. We considered individuals who were between the ages of 45 and 75 years, had tenderness to palpation or a positive grind test result, and had modified Eaton Stage 0 or 1 radiographic thumb CMC OA as potentially eligible for enrollment. Based on these criteria, 109 patients were eligible. Of the eligible patients, 19 were excluded because of a lack of interest in study participation, and another four were lost before the minimum study follow-up or had incomplete datasets, leaving 86 (43 female patients with a mean age of 53 ± 6 years and 43 male patients with a mean age of 60 ± 7 years) patients for analysis. Twenty-five asymptomatic participants (controls) aged 45 to 75 years were also prospectively recruited to participate in this study. Inclusion criteria for controls included an absence of thumb pain and no evidence of CMC OA during clinical examination. Of the 25 recruited controls, three were lost to follow-up, leaving 22 for analysis (13 female patients with a mean age of 55 ± 7 years and nine male patients with a mean age of 58 ± 9 years). Over the 6-year study period, CT images were acquired of patients and controls in 11 thumb poses: neutral, adduction, abduction, flexion, extension, grasp, jar, pinch, grasp loaded, jar loaded, and pinch loaded. CT images were acquired at enrollment (Year 0) and Years 1.5, 3, 4.5, and 6 for patients and at Years 0 and 6 for controls. From the CT images, bone models of the first metacarpal (MC1) and trapezium were segmented, and coordinate systems were calculated from their CMC articular surfaces. The volar-dorsal location of the MC1 relative to the trapezium was computed and normalized for bone size. Patients were categorized into stable OA and progressing OA subgroups based on trapezial osteophyte volume. MC1 volar-dorsal location was analyzed by thumb pose, time, and disease severity using linear mixed-effects models. Data are reported as the mean and 95% confidence interval. Differences in volar-dorsal location at enrollment and rate of migration during the study were analyzed for each thumb pose by group (control, stable OA, and progressing OA). A receiver operating characteristic curve analysis of MC1 location was used to identify thumb poses that differentiated patients whose OA was stable from those whose OA was progressing. The Youden J statistic was used to determine optimized cutoff values of subluxation from those poses to be tested as indicators of OA progression. Sensitivity, specificity, negative predictive values, and positive predictive values were calculated to assess the performance of pose-specific cutoff values of MC1 locations as indicators of progressing OA. RESULTS: In flexion, the MC1 locations were volar to the joint center in patients with stable OA (mean -6.2% [95% CI -8.8% to -3.6%]) and controls (mean -6.1% [95% CI -8.9% to -3.2%]), while patients with progressing OA exhibited dorsal subluxation (mean 5.0% [95% CI 1.3% to 8.6%]; p < 0.001). The pose associated with the most rapid MC1 dorsal subluxation in the progressing OA group was thumb flexion (mean 3.2% [95% CI 2.5% to 3.9%] increase per year). In contrast, the MC1 migrated dorsally much slower in the stable OA group (p < 0.001), at only a mean of 0.1% (95% CI -0.4% to 0.6%) per year. A cutoff value of 1.5% for the volar MC1 position during flexion at enrollment (C-statistic: 0.70) was a moderate indicator of OA progression, with a high positive predictive value (0.80) but low negative predictive value (0.54). Positive and negative predictive values of subluxation rate in flexion (2.1% per year) were high (0.81 and 0.81, respectively). The metric that most indicated a high likelihood of OA progression (sensitivity 0.96, negative predictive value 0.89) was a dual cutoff that combined the subluxation rate in flexion (2.1% per year) with that of loaded pinch (1.2% per year). CONCLUSION: In the thumb flexion pose, only the progressing OA group exhibited MC1 dorsal subluxation. The MC1 location cutoff value for progression in flexion was 1.5% volar to the trapezium , which suggests that dorsal subluxation of any amount in this pose indicates a high likelihood of thumb CMC OA progression. However, volar MC1 location in flexion alone was not sufficient to rule out progression. The availability of longitudinal data improved our ability to identify patients whose disease will likely remain stable. In patients whose MC1 location during flexion changed < 2.1% per year and whose MC1 location during pinch loading changed < 1.2% per year, the confidence that their disease would remain stable throughout the 6-year study period was very high. These cutoff rates were a lower limit, and any patients whose dorsal subluxation advanced faster than 2% to 1% per year in their respective hand poses, were highly likely to experience progressive disease. CLINICAL RELEVANCE: Our findings suggest that in patients with early signs of CMC OA, nonoperative interventions aimed to reduce further dorsal subluxation or operative treatments that spare the trapezium and limit subluxation may be effective. It remains to be determined whether our subluxation metrics can be rigorously computed from more widely available technologies, such as plain radiography or ultrasound.

Drug Candidate BGP-15 Prevents Isoproterenol-Induced Arrhythmias and Alters Heart Rate Variability (HRV) in Telemetry-Implanted Rats.

Multi-target drug candidate BGP-15 has shown cardioprotective and antiarrhythmic actions in diseased models. Here, we investigated the effects of BGP-15 on ECG and echocardiographic parameters, heart rate variability (HRV), and arrhythmia incidence in telemetry-implanted rats, under beta-adrenergic stimulation by isoproterenol (ISO). In total, 40 rats were implanted with radiotelemetry transmitters. First, dose escalation studies (40-160 mg/kg BGP-15), ECG parameters, and 24 h HRV parameters were assessed. After, rats were divided into Control, Control+BGP-15, ISO, and ISO+BGP-15 subgroups for 2 weeks. ECG recordings were obtained from conscious rats, arrhythmias and HRV parameters were assessed, and echocardiography was carried out. ISO-BGP-15 interaction was also evaluated on an isolated canine cardiomyocyte model. BGP-15 had no observable effects on the ECG waveforms; however, it decreased heart rate. HRV monitoring showed that BGP-15 increased RMSSD, SD1, and HF% parameters. BGP-15 failed to counteract 1 mg/kg ISO-induced tachycardia, but diminished the ECG of ischemia and suppressed ventricular arrhythmia incidence. Under echocardiography, after low-dose ISO injection, BGP-15 administration lowered HR and atrial velocities, and increased end-diastolic volume and ventricle relaxation, but did not counteract the positive inotropic effects of ISO. Two weeks of BGP-15 treatment also improved diastolic function in ISO-treated rats. In isolated cardiomyocytes, BGP-15 prevented 100 nM ISO-induced aftercontractions. Here, we show that BGP-15 increases vagally mediated HRV, reduces arrhythmogenesis, enhances left ventricle relaxation, and suppresses the aftercontractions of cardiomyocytes. As the drug is well tolerated, it may have a clinical value in preventing fatal arrhythmias.

The JAY (Joint Active Yoke) orthosis for a complex pip fracture-dislocation with failed volar plate repair: A case report.

INTRODUCTION: This case report details the postsurgical rehabilitation and outcome of a 57-year old neurosurgeon who underwent hemi-hamate arthroplasty and volar plate repair for a complex ring finger proximal interphalangeal (PIP) fracture-dislocation sustained after a fall while snowboarding. Following re-rupture and repair of his volar plate, the patient was fitted for a "yoke" relative motion flexor orthosis, termed a JAY (Joint Active Yoke) orthosis, in a manner reverse to that which is commonly used for extensor-related injuries. STUDY DESIGN/METHODS: A 57 yo right hand-dominant male who suffered a complex PIP fracture-dislocation with failed volar plate repair undwent hemi-hamate arthroplasty and early active motion following using a custom-fabricated joint active yoke orthosis. PURPOSE OF THE STUDY: The purpose of this study is to illustrate the benefits of this orthosis design in allowing for active controlled flexion of the repaired PIP joint with assist from the adjacent fingers, while also reducing joint torque and dorsal displacement forces. RESULTS: A satisfactory active motion outcome was achieved with maintenance of PIP joint congruity allowing the patient to return to work as a neurosurgeon at 2-months post-operatively. DISCUSSION: There is little published literature on the use of relative motion flexion orthoses following PIP injuries. Most current studies are isolated case reports on boutonniere deformity, flexor tendon repair, and closed reduction of PIP fractures. The following therapeutic intervention was considered an important contributor to a favorable functional outcome, as it minimized unwanted joint reaction forces in a complex PIP fracture-dislocation and unstable volar plate. CONCLUSION: Future research with greater level of evidence is required to establish the various applications of relative motion flexion orthoses, as well as determine the appropriate time at which to place the patient in a relative motion orthosis following operative repair to prevent long-term stiffness and poor motion.

Omecamtiv mecarbil augments cardiomyocyte contractile activity both at resting and systolic Ca2+ levels.

AIMS: Heart failure with reduced ejection fraction (HFrEF) is a disease with high mortality and morbidity. Recent positive inotropic drug developments focused on cardiac myofilaments, that is, direct activators of the myosin molecule and Ca2+ sensitizers for patients with advanced HFrEF. Omecamtiv mecarbil (OM) is the first direct myosin activator with promising results in clinical studies. Here, we aimed to elucidate the cellular mechanisms of the positive inotropic effect of OM in a comparative in vitro investigation where Ca2+ -sensitizing positive inotropic agents with distinct mechanisms of action [EMD 53998 (EMD), which also docks on the myosin molecule, and levosimendan (Levo), which binds to troponin C] were included. METHODS: Enzymatically isolated canine cardiomyocytes with intact cell membranes were loaded with Fura-2AM, a Ca2+ -sensitive, ratiometric, fluorescent dye. Changes in sarcomere length (SL) and intracellular Ca2+ concentration were recorded in parallel at room temperature, whereas cardiomyocyte contractions were evoked by field stimulation at 0.1 Hz in the presence of different OM, EMD, or Levo concentrations. RESULTS: SL was reduced by about 23% or 9% in the presence of 1 µM OM or 1 µM EMD in the absence of electrical stimulation, whereas 1 µM Levo had no effect on resting SL. Fractional sarcomere shortening was increased by 1 µM EMD or 1 µM Levo to about 152%, but only to about 128% in the presence of 0.03 µM OM. At higher OM concentrations, no significant increase in fractional sarcomere shortening could be recorded. Contraction durations largely increased, whereas the kinetics of contractions and relaxations decreased with increasing OM concentrations. One-micromole EMD or 1 µM Levo had no effects on contraction durations. One-micromole Levo, but not 1 µM EMD, accelerated the kinetics of cardiomyocyte contractions and relaxations. Ca2+ transient amplitudes were unaffected by all treatments. CONCLUSIONS: Our data revealed major distinctions between the cellular effects of myofilament targeted agents (OM, EMD, or Levo) depending on their target proteins and binding sites, although they were compatible with the involvement of Ca2+ -sensitizing mechanisms for all three drugs. Significant part of the cardiotonic effect of OM relates to the prolongation of systolic contraction in combination with its Ca2+ -sensitizing effect.

Characterization of Trapezial Pommel in Relation to Radiographic and Wear Patterns in Carpometacarpal Osteoarthritis.

BACKGROUND: Trapezial pommel, or ulnar osteophyte positioned at the vertex of the saddle-shaped facet, is a consistent structural appearance in osteoarthritis (OA) of the first carpometacarpal. This study investigates its relation to radiographic measures (modified Eaton staging and thumb OA [ThOA] index) and wear patterns (trapezial surface morphology and cartilaginous eburnation). METHODS: In all, 137 whole trapezia were explanted from 116 patients and evaluated for Eaton staging, morphology (saddle, cirque, or dish), and eburnation (degree of cartilaginous effacement) of the articular surface of the trapezium. In total, 131 Robert's views and 126 stress views were reviewed by 2 blinded senior surgeons for ThOA index and pommel size. Statistical analyses included Spearman correlation and linear regression. RESULTS: Standardized pommel size achieved good intrarater reliability (correlation coefficient: 0.80-0.98) and moderate interrater reliability (correlation coefficient: 0.60-0.67). The ThOA index and pommel size were significantly correlated across Robert's (rs = 0.51) and stress views (rs = 0.64). The ThOA index better distinguished between stages compared with pommel size. All the radiographic measures inversely correlated with preserved cartilage and varied across morphologies. Pommel size differed significantly between dish and saddle, and the ThOA index was significantly different between all morphologies when using stress views. CONCLUSIONS: We reliably quantified the pommel feature and demonstrated significant correlations with other radiographic and topologic measures of arthritic disease. If future studies can demonstrate that the pommel is a pathogenic process in ThOA and its correction can curb disease progression, the identification of the pommel feature may help guide targeted intervention.

Targeted muscle reinnervation: a brief history of a promising procedure for effective management of amputation pain.

Each year, 27.5% of the 150 000 people in the United States who require lower extremity amputation experience significant postoperative complications, including pain, infection, and need for reoperation. Postamputation pain, including RLP and PLP, is debilitating. While the causes of such pain remain unknown, neuroma formation following sensory nerve transection is believed to be a major contributor. Various techniques exist for management of a symptomatic neuroma, but few data exist on which technique is superior. Furthermore, there are few data on primary prevention of neuroma formation following injury or intentional transection. The TMR technique shows promise for both management of PLP and RLP and prevention of neuroma formation. Following amputation, transected sensory nerves are coapted to nearby motor nerve supplying remaining extremity musculature. Not only does this procedure generate increased myoelectric signals for improved prosthesis control, TMR appears to neurophysiologically alter sensory nerves, preventing formation of painful sensory neuromas. The sole RCT to date evaluating the efficacy of TMR showed statistically significant reduction in PLP. TMR is not limited to use in the setting of major limb amputation. It has also been used in the setting of post-mastectomy pain, abdominal wall neuromas, digital amputations, and headache surgeries. This article reviews the origin of TMR and provides a brief description of histologic changes following the procedure, as well as current data regarding the efficacy of TMR with regard to postoperative pain relief. It also seeks to provide a concise, comprehensive resource for providers to facilitate better discussions with patients about treatment options.