Aron T. Chacko

Anatomical Localization, Gene Expression Profiling, and Functional Characterization of Adult Human Neck Brown Fat

The imbalance between energy intake and expenditure is the underlying cause of the current obesity and diabetes pandemics. Central to these pathologies is the fat depot: white adipose tissue (WAT) stores excess calories, and brown adipose tissue (BAT) consumes fuel for thermogenesis using tissue-specific uncoupling protein 1 (UCP1). BAT was once thought to have a functional role in rodents and human infants only, but it has been recently shown that in response to mild cold exposure, adult human BAT consumes more glucose per gram than any other tissue. In addition to this nonshivering thermogenesis, human BAT may also combat weight gain by becoming more active in the setting of increased whole-body energy intake. This phenomenon of BAT-mediated diet-induced thermogenesis has been observed in rodents and suggests that activation of human BAT could be used as a safe treatment for obesity and metabolic dysregulation. In this study, we isolated anatomically defined neck fat from adult human volunteers and compared its gene expression, differentiation capacity and basal oxygen consumption to different mouse adipose depots. Although the properties of human neck fat vary substantially between individuals, some human samples share many similarities with classical, also called constitutive, rodent BAT.

Functional Outcomes for Unstable Distal Radial Fractures Treated with Open Reduction and Internal Fixation or Closed Reduction and Percutaneous Fixation: A Prospective Randomized Trial

BACKGROUND Despite the recent trend toward internal fixation of distal radial fractures, few randomized trials have examined whether volar plate fixation is superior to other stabilization techniques. The purpose of the present study was to compare (1) open reduction and internal fixation with use of a volar plate and early mobilization with (2) percutaneous fixation and casting or external fixation for the treatment of dorsally displaced unstable extra-articular and simple intra-articular fractures of the distal part of the radius, with a specific emphasis on early functional recovery. METHODS A prospective randomized study was performed at two institutions. Forty-five consecutive patients with a displaced, unstable fracture of the distal part of the radius were randomized to closed reduction and pin fixation (n = 22) or open reduction and internal fixation with a volar plate (n = 23). Clinical and radiographic assessments were conducted at six, nine, and twelve weeks after surgery and at one year. Outcome was measured on the basis of range of motion; grip and pinch strength; and Disabilities of the Arm, Shoulder and Hand scores. A questionnaire was used to determine patient satisfaction, and a detailed analysis of complications was performed. RESULTS Patients in the open reduction and internal fixation group had superior Disabilities of the Arm, Shoulder and Hand scores at six, nine, and twelve weeks. At six weeks, the average Disabilities of the Arm, Shoulder and Hand score was 27 in the open reduction and internal fixation group as compared with 53 in the closed reduction and pin fixation group (p < 0.01). At nine and twelve weeks, patients in the open reduction and internal fixation group continued to have lower scores (17 compared with 39 [p < 0.01] and 11 compared with 26 [p = 0.01], respectively). At one year, there was no significant difference between the two groups in terms of the Disabilities of the Arm, Shoulder and Hand scores. Patients in the open reduction and internal fixation group had greater range of motion and strength than patients in the closed reduction and pin fixation group at six and nine weeks, and more patients in the open reduction and internal fixation group were very satisfied with the overall wrist function and motion. Eight complications occurred, two in the open reduction and internal fixation group and six in the closed reduction and pin fixation group. CONCLUSIONS Both closed reduction with percutaneous pin fixation and open reduction with internal fixation with use of a volar plate are effective methods for the treatment of dorsally displaced, unstable, extra-articular or simple intra-articular fractures of the distal part of the radius. Better functional results can be expected in the early postoperative period in association with open reduction and internal fixation, and this form of treatment should be considered for patients requiring a faster return to function after the injury.

Predictive factors of distal femoral fracture nonunion after lateral locked plating: a retrospective multicenter case-control study of 283 fractures.

INTRODUCTION Reported initial success rates after lateral locked plating (LLP) of distal femur fractures have led to more concerning outcomes with reported nonunion rates now ranging from 0 to 21%. Reported factors associated with nonunion include comorbidities such as obesity, age and diabetes. In this study, our goal was to identify patient comorbidities, injury and construct characteristics that are independent predictors of nonunion risk in LLP of distal femur fractures; and to develop a predictive algorithm of nonunion risk, irrespective of institutional criteria for clinical intervention variability. PATIENTS AND METHODS A retrospective review of 283 distal femoral fractures in 278 consecutive patients treated with LLP at three Level1 academic trauma centers. Nonunion was liberally defined as need for secondary procedure to manage poor healing based on unrestricted surgeon criteria. Patient demographics (age, gender), comorbidities (obesity, smoking, diabetes, chronic steroid use, dialysis), injury characteristics (AO type, periprosthetic fracture, open fracture, infection), and management factors (institution, reason for intervention, time to intervention, plate length, screw density, and plate material) were obtained for all participants. Multivariable analysis was performed using logistic regression to control for confounding in order to identify independent risk factors for nonunion. RESULTS 28 of the 283 fractures were treated for nonunion, 13 were referred to us from other institutions. Obesity (BMI>30), open fracture, occurrence of infection, and use of stainless steel plate were significant independent risk factors (P<0.01). A predictive algorithm demonstrates that when none of these variables are present (titanium instead of stainless steel) the risk of nonunion requiring intervention is 4%, but increases to 96% with all factors present. When a stainless plate is used, obesity alone carries a risk of 44% while infection alone a risk of 66%. While Chi-square testing suggested no institutional differences in nonunion rates, the time to intervention for nonunion varied inversely with nonunion rates between institutions, indicating varying trends in management approach. DISCUSSION Obesity, open fracture, occurrence of infection, and the use of stainless steel are prognostic risk factors of nonunion in distal femoral fractures treated with LLP independent of differing trends in how surgeons intervene in the management of nonunion.

Does late night hip surgery affect outcome

BACKGROUND There is a perception that after-hours hip surgery may result in increased complication rates. Surgeon fatigue, decreased availability of support staff, and other logistical factors may play an adverse role. However, there are little data supporting this perception in the hip fracture literature. We present a retrospective study comparing outcomes of hip fracture surgeries performed after hours versus regular daytime hours and outcomes before and after implementation of a dedicated orthopedic trauma room staffed by a fellowship trained traumatologist. METHODS A retrospective study of 767 consecutive patients with intertrochanteric, subtrochanteric, or femoral neck fractures was performed for the years 2000 to 2006. Surgeries were stratified by time of incision into two groups: day (07:00 AM-05:59 PM) and night (06:00 PM-06:59 PM). Each group was further divided into a period before the implementation of a trauma room and the period after (August 2004). Records were examined for procedure length, intraoperative blood loss, complications (nonunion, implant failure, infection, deep vein thrombosis, pulmonary embolus, and refracture), reoperation, and mortality. RESULTS Four hundred ninety-nine patients were included the day group and 268 in the night group. There were no differences in terms of age, ethnicity, American Society of Anesthesiologists status, total number of comorbidities, and fracture type between groups. There were significantly more females in the night group than the day group. Intertrochanteric fractures were 64% of all fractures, femoral neck fractures were 34%, and subtrochanteric fractures were 2%. Duration of surgery for Dynamic Hip System procedures was significantly longer in the night group and also before the trauma room became available. These differences in duration of surgery also correlate with blood loss differences between the groups. Intramedullary nails also took longer to do at night. Hemiarthroplasties demonstrated no significant differences. The 1-year and 2-year mortalities of hip fracture patients operated during daytime hours in a trauma room (13 and 15%, respectively) were significantly less than they were before the implementation of the trauma room (25 and 37%, respectively). When the effect of the trauma room was eliminated, there were no significant differences between overall daytime and nighttime mortalities at 1 month, 1 year, and 2 years. There were no significant differences in other complications noted between the different groups. CONCLUSIONS We recommend that nighttime surgery should not be dismissed in hip fracture patients that would otherwise benefit from an early operation. However, there seems to be a decreasing trend in mortality when hip fractures are operated in a dedicated daytime trauma room staffed by a dedicated traumatologist.

Driving after musculoskeletal injury. Addressing patient and surgeon concerns in an urban orthopaedic practice

Patient and public safety concerns make the timing of return to driving after musculoskeletal injury or orthopaedic surgery an important decision that is made by orthopaedic surgeons on a daily basis. Neither the American Academy of Orthopaedic Surgeons nor any other orthopaedic specialty society has endorsed recommendations, policies, or practice guidelines that address when a patient is able to return to driving after a musculoskeletal injury. To our knowledge, there are no specific guidelines available on how the decision should be made, who should be involved, or to what extent retesting of driving abilities after an injury should be required. The only and most recent guidelines available were developed in 2003 by the National Highway Traffic Safety Administration (NHTSA) in cooperation with the American Medical Association specifically to assess the ability to return to driving in older patients1. While these guidelines address to a limited degree musculoskeletal disability in older individuals, they are not specific to musculoskeletal injury or orthopaedic surgery and they are not entirely applicable to younger age groups. They also fail to incorporate a substantial part of the already limited orthopaedic literature on the topic2-10. The American Occupational Therapy Association (AOTA) is the only organization that has addressed the issue and actually offers Driving and Community Mobility Specialty Certification for occupational therapists who seek the training (www.aota.org). Comprehensive evaluation of driving abilities, as recommended by the AOTA, involves both an office evaluation and a behind-the-wheel assessment administered in a properly equipped test vehicle. Unfortunately, such specialized programs are not standard in conventional occupational therapy practices and are not always geographically or financially accessible to all patients recovering from musculoskeletal injury or orthopaedic surgery. To address the issue of return to driving in our practice, we formulated a return-to-driving policy that takes …

Social Networking Among Upper Extremity Patients

PURPOSE Despite their rising popularity, the health care profession has been slow to embrace social networking sites. These are Web-based initiatives, designed to bring people with common interests or activities under a common umbrella. The purpose of this study is to evaluate social networking patterns among upper extremity patients. METHODS A total of 742 anonymous questionnaires were distributed among upper extremity outpatients, with a 62% response rate (462 were completed). Demographic characteristics (gender, age, level of education, employment, type of health insurance, and income stratification) were defined, and data on computer ownership and frequency of social networking use were collected. Social network users and nonusers were compared according to their demographic and socioeconomic characteristics. RESULTS Our patient cohort consisted of 450 patients. Of those 450 patients, 418 had a high school education or higher, and 293 reported a college or graduate degree. The majority of patients (282) were employed at the time of the survey, and income was evenly distributed among U.S. Census Bureau quintiles. A total of 349 patients reported computer ownership, and 170 reported using social networking sites. When compared to nonusers, social networking users were younger (p<.001), more educated (p<.001), and more likely to be employed (p = .013). Users also had higher income levels (p=0.028) and had high rates of computer ownership (p<.001). Multivariate regression revealed that younger age (p<.001), computer ownership (p<.001), and higher education (p<.001) were independent predictors of social networking use. Most users (n = 114) regularly visit a single site. Facebook was the most popular site visited (n=142), followed by MySpace (n=28) and Twitter (n=16). CONCLUSIONS Of the 450 upper extremity patients in our sample, 170 use social networking sites. Younger age, higher level of education, and computer ownership were associated with social networking use. Physicians should consider expanding their use of social networking sites to reach their online patient populations.

A novel methodology for the study of injury mechanism: ankle fracture analysis using injury videos posted on YouTube.com

Purpose: An inherent deficiency in the understanding of the biomechanics of fractures is the reliance on cadaveric or other nonphysiological injury models resulting from the prohibitive ethical and practical considerations of conducting injury studies in live participants. We describe a novel methodology for studying injury mechanisms using in vivo injury videos obtained from Youtube.com demonstrating injuries as they occur in real time and correlating them with the resulting injury radiographs. Methods: Over 1000 video clips of potential ankle fractures were assessed for clear visualization of the mechanism of injury, including the foot position and deforming force. Candidate videos were selected if the mechanism of injury was classifiable by those described by Lauge-Hansen and there appeared to be a significant mechanism to likely cause fracture. X-rays were then requested from the individuals posting the video clips. Videos and x-rays were reviewed and classified using the Lauge-Hansen system in a blinded manner. The deforming mechanism in the video clips was classified as supination external rotation, supination adduction (SAD), pronation external rotation (PER), or pronation abduction. X-ray fracture patterns were similarly classified. Results: Two hundred forty videos were selected and individuals posting the videos were contacted. Of 96 initial positive responses, we collected 15 videos with their corresponding radiographs. Eight had SAD-deforming trauma and seven had PER-deforming trauma as appreciated in the videos. There were 12 true ankle fractures. All five fractures judged by video to be SAD injuries resulted in a corresponding SAD pattern radiographic ankle fractures. Of the seven fractures judged by video to be PER injuries, only two resulted in PER pattern radiographic ankle fractures. Five PER injuries resulted in supination external rotation ankle fracture patterns. Conclusion: Our series shows that when in vivo injury videos are matched to their corresponding x-rays, the Lauge-Hansen system is only 58% overall accurate in predicting fracture patterns from deforming injury mechanism as pertaining to SAD and PER injury mechanisms. All SAD injuries correlated but only 29% of PER injuries resulted in a PER fracture pattern. This study illustrates the ethical and practical difficulties of using public access Internet YouTube videos for the study of injury dynamics. The current case series illustrates the methods potential and may lead to future research analyzing the validity of the Lauge-Hansen classification system as applied to in vivo injuries.

The Rheumatoid Thumb

Rheumatoid arthritis of the thumb is a common source of disability. Obtaining an understanding of the underlying biologic and physical manifestations of rheumatoid arthritis is essential in the choice of treatment of the disease. In the early stages of the disease, conservative and less invasive measures can be used. In the more advanced stages, arthrodesis and arthroplasty are often used. Isolated interphalangeal involvement is best managed with arthrodesis. Metacarpophalangeal involvement in low-demand patients can be treated with arthroplasty, whereas arthrodesis can be used in more active patients. Patients who have carpometacarpal joint damage are best treated with trapezium resection arthroplasty.

Effect of surgeon training, fracture, and patient variables on calcaneal fracture management.

Background: There appears to be a general lack of consensus in treating calcaneus fractures. Many different patient-based variables such as smoking, diabetes, or occupation, may influence treatment decisions possibly more so than the nature of the injury itself. Indications for operative versus nonop-erative treatment are often unclear. The goals of this study were to determine if lack of consensus exists, determine which factors most influence orthopaedic surgeons in choosing operative versus nonoperative treatment and determine if there are differences in treatment based on fellowship training and exposure to these injuries. Materials and Methods: Practicing orthopaedic surgeons of various backgrounds and training were administered an electronic survey. The survey consisted of clinical vignettes and questions regarding fellowship training, demographics and exposure to calcaneus fractures. Orthopaedic surgeons were asked to weigh the importance of patient-based variables in determining operative versus nonoperative treatment. Results: For patients with an uncomplicated medical history, there was a general consensus on treatment as guided by the Sanders classification. For those with a complex medical history, there was less consensus on management despite fracture pattern. Foot & ankle fellowship-trained surgeons (F&AT) ranked calcaneal deformity as more important than trauma fellowship-trained surgeons (NFT), and ranked peripheral vascular disease (PVD)/diabetes mellitus (DM) more important than did both trauma fellowship-trained surgeons (TFT) and NFT surgeons. There was no significant difference in choosing operative versus nonoperative treatment for surgeons treating more calcaneus fractures (more than four per month) versus those who treated fewer (less than one a month). Conclusion: There was general agreement among surgeons regarding the most important variables for determining management of calcaneus fractures. How this information is utilized varies according to practitioner and leads to varying consensus. There was generalized consensus regarding management in cases of anatomic deformity at either end of the spectrum of severity and non-complex medical histories. When additional confounders were added, the agreement between surgeons declined.

Financial implications of nonoperative fracture care at an academic trauma center.

Objective: To determine if nonoperative fracture Current Procedural Technology codes generate a significant portion of annual revenues in an academic practice. Design: Retrospective review of an orthopaedic trauma practice billings during fiscal year 2008. Setting: An urban level-1 trauma center. Patients: Outpatient clinic, and all consults, to the orthopaedic trauma service in the emergency room and hospital wards staffed by an attending traumatologist. Main Outcome Measurements: An analysis was made of relative value units (RVUs) generated by operative and nonoperative care, separating the later into clinic, consults, and closed (nonoperative) fracture treatment. Results: A total of 19,815 RVUs were generated by the trauma service during the 2008 fiscal year. Emergency department and ward consults generated 2176 (11%) of RVUs, whereas outpatient clinic generated an additional 1313 (7%) of RVUs. Nonoperative (closed) fracture care generated 2725 (14%) RVUs, whereas surgical procedures were responsible for the remaining 13,490 (68%) of RVUs. In terms of overall financial reimbursement, nonoperative management, consults, and office visits generated 31% of income for the trauma service. Conclusions: Although the largest financial contribution to a busy surgical practice is operative procedures, 1 must not overlook the important impact of nonoperative fracture care and consults. In our academic center, nearly one-third of all income was generated from nonsurgical procedures. In the current medical/financial climate, 1 must be diligent in optimizing the finances of trauma care to sustain an economically viable practice. Level of Evidence: Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.