Be a Lighthouse for Your Medical Students: How to Help Them Navigate During Changing Times to a Successful Match.

The transition between medical school and residency is a complex, multifaceted process that is commonly a time of stress and uncertainty for medical students. Occupying most of a student's final year of medical school, the residency application includes a primary Electronic Residency Application Service application, a variable number of program-specific secondary applications, and interviews. The application process culminates with The Match. Orthopaedic surgery is among the more competitive specialties; thus, it is critical that all involved parties understand the complexity of the process and the numerous variables that play into such a critical decision point in the career trajectory of a future physician. It is important to provide a mentor with an overview of the residency application process, specifically with respect to orthopaedic surgery, so that they may be best prepared to guide their medical student mentee through the process and help them find success.

Nerve Compression Syndromes of the Upper Extremity.

Nerve compression syndromes of the upper extremity are among the most common pathologies encountered in orthopaedic surgery. Symptoms can be debilitating for patients-affecting their work, activity level, sleep patterns, and overall quality of life. The community orthopaedic specialist should be familiar with the anatomy, etiology, and presentation of upper extremity nerve entrapment. Furthermore, knowledge of current evidence surrounding the management of these common syndromes can prove valuable for treating clinicians. Treatment ranges from nonsurgical (including medication and splinting) to surgical (when symptoms are severe). Although the gold standard treatment for nerve compression syndromes of the upper extremity is typically surgical release, nonsurgical methods should also be reviewed and understood because these can play an important role for patients as well. Community orthopaedic specialists should be well aware of the risks and complications associated with surgical releases.

Building Blocks of Wellness: Where Do We Start When Our Tasks Have No End?

Surgeon wellness, and the means by which it may be realized, has recently come to the forefront as awareness of burnout among orthopaedic surgeons has increased. Individual surgeons face unique challenges toward finding their own path to thrive. It is important to incorporate varying perspectives regarding potential solutions to surgeons' stresses in both work and extracurricular life. Specifically, the goal is to initiate a discussion regarding wellness by providing insight into the challenges facing surgical residents, supplemented with the perspectives of women and minorities within the field. Peer coaching plays an essential role in optimizing mental health.

Hand size affects branching of the deep ulnar nerve and deep palmar arch.

PURPOSE: Understanding the anatomy of the deep neurovascular structures of the hand is essential in surgical planning. There is a lack of literature regarding hand size and its influence in branching variation and the distances between branches of various neurovascular structures. Our study quantifies the variation in branching distances of the deep ulnar nerve and deep palmar arch branches. METHODS: Twenty-five fresh-frozen cadaveric hands were dissected. Each branch of the deep ulnar nerve and deep palmar arch was identified. The distance from the most distal portion of the pisiform to the proximal aspect of the branch was measured. The relationship between the length of the third metacarpal and the distance of each branch from the pisiform was examined. RESULTS: There was no relationship between branching differences in the deep ulnar nerve and the length of the third metacarpal. There was a significant association between the length of the third metacarpal and the second, third, and fourth branches of the deep palmar arch (p < 0.05). CONCLUSIONS: Our study found a significant association between the branching distances of the second, third, and fourth branches of the deep palmar arch and hand size as measured by the length of the third metacarpal.

Nerve Compression Syndromes of the Shoulder.

Nerve compression syndromes of the shoulder contribute to pain, paresthesia, and weakness of the upper extremity. This review examines the recent literature regarding thoracic outlet syndrome, suprascapular neuropathy, long thoracic nerve palsy, and quadrilateral space syndrome. Overlapping features are common among shoulder pathologies, and thus, key anatomical features, pathophysiology, clinical manifestations, diagnostic techniques, and treatments are highlighted for all aforementioned conditions.

Evaluation of A2 and A4 Hand Pulley Repair Using Tendon Graft Rings.

PURPOSE: To compare the mechanical characteristics of A2 and combined A2-A4 pulley repair in the intact and damaged flexor pulley system. METHODS: After control testing, we recorded tendon excursion and flexion of 11 cadaveric fingers after several interventions: (1) complete excision of A2 and A4, (2) repair of the A2 with one ring of tendon graft, (3) repair of the A2 with 2 rings of tendon graft, and (4) repair of the A2 with 2 rings combined with repair the A4 with one ring. RESULTS: At the proximal interphalangeal (PIP) joint, the maximum rotational angle decreased by an average of 30% after complete excision of the A2 and A4 pulleys. This angle was still decreased compared with the control by an average of 25% after one-ring repair at A2, 23% after 2-ring repair at A2, and 17% after 2-ring repair at A2 combined with one-ring repair at A4. At the metacarpophalangeal joint, the average maximum rotational angle decreased by an average of 17% after complete excision of the A2 and A4 pulleys. This angle was still decreased compared with the control by an average of 11% after one-ring repair at A2, 7% after 2-ring repair at A2, and 4% after 2-ring repair at A2 combined with one-ring repair at A4. Kinematic behavior at the PIP joint with an intact pulley system was most closely approximated by the 3-loop repair. The least similar behavior was with a 2-ring construct at A2. CONCLUSIONS: All repairs increased average flexion at the PIP and metacarpophalangeal joints compared with the unrepaired samples. The 3-ring configuration exhibited a higher recovery of PIP flexion compared with the other repairs. CLINICAL RELEVANCE: Although each repair restored flexion, clinical studies are necessary to evaluate the clinical relevance of the mechanical results of this study.

Preoperative Risk Factors for Postoperative Urinary Tract Infection After Primary Total Hip and Knee Arthroplasties.

BACKGROUND: Establishing clear risk factors for complications such as urinary tract infection (UTI) after arthroplasty procedures helps guide clinical practice and provides more information to both surgeons and patients. This study aims to assess selected preoperative patient characteristics as risk factors for postoperative UTI after primary total hip and knee arthroplasties (THA and TKA). METHODS: This was a retrospective analysis using current procedural terminology codes to investigate the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database for patients who underwent THA or TKA from 2010 to 2017. Patients were classified for UTI by NSQIP guidelines. Patient samples with all possible covariates were included for multivariate logistic regression analysis and assessed for independent associations. RESULTS: In a cohort of 983 identified patients (983 of 119,096; 0.83%): ages 57+ years, preoperative red blood cell (RBC) transfusion, perioperative RBC transfusion, bleeding disorders, operative time 110+ minutes, preoperative steroid use, diabetes, pulmonary comorbidities, body mass index 30+ kg/m2 were independent risk factors for postoperative UTI after THA. In a cohort of 1503 identified patients (1503 of 189,327; 0.8%): ages 60+ years, preoperative RBC transfusion, perioperative RBC transfusion, anemia, platelets less than 150k, preoperative steroid use, diabetes, and body mass index 30+ kg/m2 were independent risk factors for postoperative UTI after TKA. Male sex was associated with a decreased risk of UTI in both THA and TKA. CONCLUSION: This study provides novel evidence on risk factors associated with the development of UTI after THA or TKA. Clinicians should be aware of risk factors in the manifestation of postoperative UTI after primary THA or TKA procedures.

Abnormal Coagulation as a Risk Factor for Postoperative Complications After Primary and Revision Total Hip and Total Knee Arthroplasty.

BACKGROUND: Patients undergoing total joint arthroplasty (TJA) have an increased likelihood of having an abnormal coagulation profile compared with the general population. Coagulation abnormalities are often screened for before surgery and considered during perioperative planning. This study assesses a preoperative abnormal coagulation profile as a risk factor for postoperative complications after total hip arthroplasty (THA), revision THA (rTHA), total knee arthroplasty (TKA), and revision TKA (rTKA) and then examines specific coagulopathies to determine their influence on complication rates. METHODS: Patients who underwent THA, rTHA, TKA, or rTKA from 2011 to 2017 were identified in the American College of Surgeons National Surgical Quality Improvement Program database and then assessed for preoperative abnormal coagulation profiles. Various postoperative complications were analyzed for each cohort, and two separate multivariate regression analyses were used to assess the relationship between abnormal coagulation and postoperative complications. RESULTS: 403,566 THA, rTHA, TKA, or rTKA cases were identified, and 40,466 (10.0%) of patients were found to have an abnormal coagulation profile. Patients with preoperative coagulation abnormalities had higher likelihoods of postoperative complications after primary TJA than in revision TJA. An international normalized ratio>1.2 was associated with the most types of postoperative complications, followed by a bleeding disorder diagnosis. A partial thromboplastin time>35 seconds was associated with only one type of postoperative complication, while a platelet count <150,000 per µL was associated with postoperative complications only after TKA. CONCLUSION: TJA in patients with abnormal coagulation profiles may result in adverse outcomes. These patients may benefit from preoperative intervention. Prophylactic care needs to be personalized to the specific coagulation abnormalities present.

A novel method for predicting superior gluteal nerve safe zones in the lateral approach to the hip.

INTRODUCTION: The superior gluteal nerve (SGN) is at risk for laceration during lateral approach total hip arthroplasty (THA). The purpose of this study is to assess the accuracy of the trochanter-to-iliac crest distance (TCD) and the nerve-to-trochanter distance (NTD) ratio in determining a reproducible safe zone around the SGN independent of height. MATERIALS AND METHODS: Eighteen hemipelvises were dissected and the SGNs were exposed. The distance (NTD) from greater trochanter (GT) to the most inferior branch of the SGN encountered in each of the three approaches (Bauer et al., 1979) was measured. A reference distance (TCD) was measured from the GT to the highest point on the iliac crest. The NTD was divided by the TCD to generate standardized ratios. Coefficient of variation CV = (SD/mean) × 100 was calculated for each distance and ratio to measure relative variability. RESULTS: The standardized ratios (and CV) were determined for the nerve branches in three different surgical approaches: Hardinge 0.464 (0.9%), Bauer 0.406 (1.7%), and Frndak 0.338 (4.1%). There was a strong correlation of the individual NTDs with the TCD: NTD for Hardinge (r = 0.996, p < .001), NTD for Bauer (r = 0.984, p < .001), and NTD for Frndak (r = 0.932, p < .001). CONCLUSION: By measuring the TCD preoperatively and using the respective standardized ratios, surgeons can accurately predict the NTD and how proximal to the GT each SGN branch can be expected to be encountered during lateral approach to the hip. This will allow surgeons to work with a more precise safe zone around the SGN and minimize the possibility for a nerve injury.

Histological Assessment of Wallerian Degeneration of the Rat Tibial Nerve Following Crush and Transection Injuries.

BACKGROUND: Wallerian degeneration (WD) following peripheral nerve injury (PNI) is an area of growing focus for pharmacological developments. Clinically, WD presents challenges in achieving full functional recovery following PNI, as prolonged denervation of distal tissues for an extended period of time can irreversibly destabilize sensory and motor targets with secondary tissue atrophy. Our objective is to improve upon histological assessments of WD. METHODS: Conventional methods utilize a qualitative system simply describing the presence or absence of WD in nerve fibers. We propose a three-category assessment that allows more quantification: A fibers appear normal, B fibers have moderate WD (altered axoplasm), and C fibers have extensive WD (myelin figures). Analysis was by light microscopy (LM) on semithin sections stained with toluidine blue in three rat tibial nerve lesion models (crush, partial transection, and complete transection) at 5 days postop and 5 mm distal to the injury site. The LM criteria were verified at the ultrastructural level. This early outcome measure was compared with the loss of extensor postural thrust and the absence of muscle atrophy. RESULTS: The results showed good to excellent internal consistency among counters, demonstrating a significant difference between the crush and transection lesion models. A significant decrease in fiber density in the injured nerves due to inflammation/edema was observed. The growth cones of regenerating axons were evident in the crush lesion group. CONCLUSION: The ABC method of histological assessment is a consistent and reliable method that will be useful to quantify the effects of different interventions on the WD process.

Readability Level of English and Spanish Orthopaedic Patient Education Materials English and Spanish Patient Education.

There are 16 million Hispanic people in the United States who rely on Spanish as their only effective method of communication. However, there is a scarcity of literature evaluating if patient education resources in Spanish meet the average American reading level or National Institute of Health (NIH) and American Medical Association (AMA) grade-level recommendations, especially in the field of orthopaedics. Representative orthopaedic search terms were input into Google and ten articles pertaining to patient education were selected. Videos, scientific journals, and surgical technique guides were excluded. Articles were then digitally analyzed and compared. Mean United States grade level equivalent was 11.26 ± 2.23 for English articles and 10.55 ± 1.45 for Spanish articles. English orthopaedic materials featured a significantly more difficult grade level (p < 0.01) than equivalent Spanish works. Spanish orthopaedic materials generated in the United States featured significantly lower (p < 0.01) readability scores than those written outside the United States. Our study demonstrated both English and Spanish materials were written at a high school level. Spanish materials were written at more appropriate grade-levels than their English counterparts. (Journal of Surgical Orthopaedic Advances 30(2):096-100, 2021).

Role of Depression in Total Knee Arthroplasty: A Retrospective Analysis of Perioperative Outcomes in Patients in the United States.

We evaluate the patient demographics, perioperative outcomes, in-hospital complications, and assess recent national trends in clinically depressed and non-depressed patients undergoing primary total knee arthroplasty (TKA). Using the National Hospital Discharge Survey from 2001 and 2010, patients undergoing primary TKA in the United States were identified based upon the diagnosis of depression. Differences in gender, patient-demographics, comorbidities, complications, length of stay, and discharge disposition were analyzed. A total of 32,761 TKA patients were identified, consisting of 1,880 patients with a diagnosis of depression and 30,881 patients without. The depression group had an average age significantly younger than the non-depression cohort (p < 0.01). The depression group contained a significantly greater percentage of females when compared to the non-depression group. The non-depression group had a significantly greater percentage of African-Americans (p < 0.01), and a significantly smaller percentage of Caucasians (p < 0.01). Our findings contribute to the literature on the role of depression on perioperative outcomes of TKA. (Journal of Surgical Orthopaedic Advances 30(1):007-009, 2021).

Does Virtual Reality Improve Procedural Completion and Accuracy in an Intramedullary Tibial Nail Procedure? A Randomized Control Trial.

BACKGROUND: Artificial reality technologies are currently being explored as potential options to improve surgical education. Previous studies have primarily examined the efficacy of artificial reality in laparoscopic procedures, but to our knowledge, none have been performed in orthopaedically relevant procedures such as intramedullary tibial nailing, which calls for more versatile large-scale movements. QUESTIONS/PURPOSES: Does a virtual reality simulator with or without a standard technique guide result in (1) a higher proportion of participants who completed the insertion of an intramedullary tibial nail in a synthetic bones model and (2) greater procedural accuracy than does training with a technique guide alone? METHODS: Twenty-five first- and second-year medical students without prior exposure to intramedullary tibial nail insertion were recruited. Participants were randomly assigned to the technique guide control group (n = 8), the virtual reality group (n = 8), or the virtual reality and technique guide group (n = 9). The technique guide was adapted from a commercially available technique guide, which participants in the assigned groups could use to prepare as much as desired. The virtual reality simulation was based on the same procedure, and we used a commercially available virtual reality simulator that we purchased for this task. Participants in the virtual reality experimental groups completed the simulation on three separate sessions, at a set interval of 3 to 4 days apart. After 10 to 14 days of preparation, all participants attempted to insert an intramedullary nail into an intact, compact bone-model tibia that lacked surrounding soft tissue. Participants were given written hints if requested, but no other assistance was given. A procedure was considered complete if the nail and screw were properly placed. Procedural accuracy was defined as the number of incorrect steps normalized out of the 16 possible performed. After the procedure, one orthopaedic surgeon assessed a blinded video of the participant performing it so the assessor could not recognize the individual or that individual's gender. Additionally, the assessor was unaware of which group each participant had been randomized to during the evaluation. RESULTS: A higher proportion of participants in the virtual reality group (6 of 8) and the virtual reality and technique guide group (7 of 9) completed the intramedullary nail than did participants in the technique guide group (2 of 8; p = 0.01). There was no difference in completion between the virtual reality groups (p = 0.89). Participants in the virtual reality and virtual reality and technique guide had fewer normalized incorrect steps than did participants in the technique guide group (3.2 ± 0.1 of 16 and 3.1 ± 0.1 of 16 versus 5.7 ± 0.2 of 16, respectively; p = 0.02 for comparisons of virtual reality groups to technique guide, p = 0.63 between the virtual reality group). CONCLUSIONS: Virtual reality increased both procedural accuracy and the completion proportion compared with a technique guide in medical students. Based on our findings, virtual reality may help residents learn the procedural workflow and movements required to perform surgical procedures. Future studies should examine how and when exactly the technology can be applied to residencies and its impact on residents. LEVEL OF EVIDENCE: Level I, therapeutic study.

Urinary Tract Infection after Total Hip Arthroplasty: A Retrospective Cohort Study.

Perioperative urinary tract infections (UTI) are a relatively common occurrence after total hip arthroplasty (THA). The purpose of this study was to assess demographics, outcomes and trends in the development of UTI's after THA using the National Hospital Discharge Survey (NHDS). All patients undergoing THA were divided based on whether or not they developed a UTI, and data regarding demographics, outcome and complications were gathered and analyzed. No significant trend in rate of UTI after THA was found. Patients who developed a UTI were more likely to be female, have more comorbidities and receive a transfusion. They had a longer hospitalization, lower rate of discharge directly home and an increased rate of discharge to a rehabilitation facility. Orthopaedists should identify those patients at increased risk who according to this study appear to be older, female patients with multiple co-morbidities who received a blood transfusion. (Journal of Surgical Orthopaedic Advances 29(3):162-164, 2020).

In Hospital Outcomes of Total Hip Arthroplasty in the Medicaid Population.

Total hip arthroplasty (THA) is one of the most common orthopaedic procedures. This study's purpose was to evaluate national trends, patient demographics and hospital outcomes for Medicaid patients who underwent a primary THA. The National Hospital Discharge Survey (NHDS) database was queried for patients undergoing THA from 2001-2010. Patients were stratified into two groups based on insurance. We found from 2001-2005, Medicaid accounted for 2.38% of all THA performed, increasing insignificantly to 2.61% between 2006-2010. The Medicaid group was younger (50.3 vs. 65.6 years, p < 0.01). Length of stay was longer for the Medicaid group (4.6 vs. 4.0 days, p < 0.01). Medicaid patients were more likely to be discharged home (53.7% vs. 47.2%, p < 0.01) and less likely to be discharged to rehabilitation facilities (24.4% vs. 29.0%, p < 0.05). In conclusion, we discovered that the rate of Medicaid insurance in patients undergoing primary THA was stable through 2010, prior to the Affordable Care Act. We found Medicaid THA patients had longer length of stay, despite being a mean 15 years younger than the non-Medicaid cohort. Medicaid insurance status should be factored into risk adjustment models to avoid creating additional disincentive to treat the Medicaid population. (Journal of Surgical Orthopaedic Advances 28(4):281-284, 2019).

Biomechanics of the Acute Boutonniere Deformity.

PURPOSE: To demonstrate which structures of the extensor mechanism create a boutonniere deformity, when damaged, in a cadaver model. An analysis of how damage to these anatomical structures affects the biomechanical performance of the extensor mechanism was also performed. METHODS: We secured 18 fresh cadaveric hands onto an apparatus consisting of a computer-controlled motor and tensiometer attached in series to the extensor communis tendon of the ring and middle digits. The central slip, transverse, and oblique fibers of the interosseous hood and the triangular ligament were sequentially divided. After each structure was divided, the motors were activated to provide a constant tendon displacement force. The angular displacement at the proximal interphalangeal (PIP) and distal interphalangeal joints was recorded. RESULTS: In all digits, detachment of the central slip from the middle phalanx produced a decrease in extension of the PIP joint. When the transverse and oblique fibers of the interosseous hood were also divided, extension at the PIP joint was further decreased. A boutonniere deformity occurred only when all 3 structures were damaged. CONCLUSIONS: The boutonniere deformity requires subluxation of the lateral bands volar to the axis of rotation of the PIP joint. This study demonstrates that damage to the central slip alone does not cause the deformity. Combined injury of the central slip, triangular ligament, and transverse and oblique fibers of the interosseous hood causes a boutonniere deformity. CLINICAL RELEVANCE: Division of the central slip leads to loss of extension at the PIP joint. A more substantial loss of extension after injury or development of a boutonniere deformity should alert clinicians that other structures of the extensor mechanism are also damaged.

Blood Transfusion After Primary Total Hip Arthroplasty: National Trends and Perioperative Outcomes.

The purpose of this study was to quantify the changes in transfusion rates, both allogeneic blood transfusion (ALBT) and autogenic blood transfusion (ATBT) on a national scale, and determine patient factors associated with transfusions. The National Hospital Discharge Survey was evaluated between 2001 and 2010 for primary total hip arthroplasty (THA) patients and categorized on the basis of transfusion necessity, type, and comorbidity burden. A logistic regression comparison of ALBT, ATBT, and nontransfused patients was performed with respect to patient demographics and in-hospital complications. The proportion of patients requiring any transfusion decreased from an average rate of 22.8% between 2001 and 2005 to 21.2% between 2006 and 2010 (p = .01). ATBT rates decreased (r = -.99) from 11.0% in 2001 to 2.8% in 2010. ALBT rates increased (r = .66) from 14% in 2001 to 16.6% in 2010. The number of patients requiring a blood transfusion after THA decreased in the United States with a trend shifting from ATBT to ALBT. (Journal of Surgical Orthopaedic Advances 26(4):216-222, 2017).

Surgical Risks and Costs of Care are Greater in Patients Who Are Super Obese and Undergoing THA.

BACKGROUND: Patients with morbid obesity, defined as a BMI greater than 40 kg/m2, and super obesity, defined as a BMI greater than 50 kg/m2, increasingly present for total hip replacement. There is disagreement in the literature whether these individuals have greater surgical risks and costs for the episode of care, and the magnitude of those risks and costs. There also is no established threshold for obesity as defined by BMI in identifying increased complications, risks, and costs of care. Until recently, analysis of higher BMI data was limited to small cohorts from hospital-based data banks, based on BMI or height and weight only, often as part of a multivariate analysis. On October 1, 2010 the Centers for Medicare & Medicaid Services added a fifth digit to the BMI data, V85.xx, in the Medicare data bank, which allowed data mining of cases of patients with higher BMI. To our knowledge, our study is the first large retrospective Medicare data mining study, which allows us to examine BMI levels greater than 40 and 50 kg/m2 to delineate risks, complications, and costs for these patients. QUESTIONS/PURPOSES: We sought to quantify (1) the surgical risk, and (2) the costs associated with complications after THA in patients who were morbidly obesity (BMI ≥ 40 kg/m2) or super obese (BMI ≥ 50 kg/m2). METHODS: This is a retrospective study of patients, using Medicare hospital claims data, who underwent THA. The ICD-9 Clinical Modification (CM) diagnosis code V85.4x was used to identify patients with morbid obesity and with super obesity from October 1, 2010 through December 31, 2014. Patients without any BMI-related diagnosis codes were used as the control group. Twelve complications occurring during the 90 days after THA were analyzed using multivariate Cox models adjusting for patient demographic, comorbidities, and institutional factors. In addition, hospital charges and payments were compared from primary surgery through the subsequent 90 days. RESULTS: Patients with morbid obesity had increased postoperative complications including prosthetic joint infection (hazard ratio [HR], 3.71; 95% CI, 3.2-4.31; p < 0.001), revision (HR, 1.91; 95% CI, 1.69-2.16; p < 0.001), and wound dehiscence (HR, 3.91; 95% CI, 3.14-4.86; p < 0.001). In addition, patients with morbid obesity had increased risk of deep vein thrombosis (HR, 1.43; 95% CI, 1.14-1.79; p < 0.002), pulmonary embolism (HR, 1.57; 95% CI, 1.25-1.99; p < 0.001), implant failure (HR, 1.48; 95% CI, 1.3-1.68; p < 0.001), acute renal failure (HR, 1.68; 95% CI, 1.56-1.80; p < 0.001), and all-cause readmission (HR, 1.48; 95% CI, 1.40-1.56; p < 0.001). However, death (HR, 0.94 95% CI, 0.73-1.19 p < 0.592), acute myocardial infarction (HR, 0.94; 95% CI, 0.74-1.2 p < 0.631), and dislocation (HR 1.07; 95% CI, 0.85-1.34; p < 0.585) were not different between patients in the control and morbidly obese groups. Super obese patients had an increased risk of infection (HR, 6.48; 95% CI, 4.54-9.25; p < 0.001), wound dehiscence (HR, 9.81; 95% CI, 6.31-15.24; p < 0.001), and readmission (HR, 2.16; 95% CI, 1.84-2.54; p < 0.001) compared with patients with normal BMI. Controlling for patient and institutional factors, each THA had mean total hospital charges of USD 88,419 among patients who were super obese compared with USD 73,827 for the control group, a difference of USD 14,591. Medicare payment for the patients who were super obese also was higher, but only by USD 3631. CONCLUSIONS: Patients who are super obese are at increased risk for serious complications compared with patients with morbid obesity, whose risks are elevated relative to patients whose BMI is less than 40 kg/m2. Costs of care for patients who were super obese, likewise, were increased. We present BMI outcomes to allow an objective basis for patient counseling, risk stratification, maintaining access to orthopaedic surgical care, and maintaining hospital operating margins. LEVEL OF EVIDENCE: Level III, therapeutic study.

Validating a Modified Circle Theorem Method for the Measurement of Acetabular Cup Anteversion on Plain Radiography with Intra-Operative Data from Robotic Assisted Total Hip Arthroplasty.

This study aims to validate a modified circle theorem method for the calculation of true version of the acetabular component on anteroposterior x-rays with intra-operative version data derived from robotic assisted total hip arthroplasty (THA). Planar anteversion measurements recorded intraoperatively in 80 THAs were correlated to measurements on anteroposterior radiographs. The mean anteversion of the cohort measured by the robotic system and on plain radiography was 21.2° ± 2.0° and 19.9° ± 3.4° respectively and 97.5% of cases were in a 30% relative error. The correlation between the true and planar measurements of anteversion on plain radiographs was strong (Pearson correlation coefficient of 0.9422). We conclude that the circle theorem method can be validated with data from robotic guided THA.

Risk and Cost of 90-Day Complications in Morbidly and Superobese Patients After Total Knee Arthroplasty.

BACKGROUND: This study investigated the risk and cost of postoperative complications associated with morbid and super obesity after total knee arthroplasty (TKA). METHODS: A retrospective cohort study was conducted of patients who underwent TKA using Medicare hospital claims data. The International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code V85.4x was used to identify morbidly obese patients (body mass index [BMI] ≥40 kg/m(2)) and superobese patients (BMI ≥50 kg/m(2)) in 2011-2013. Patients without any BMI-related diagnosis codes were used as controls. Twelve complications occurred in the 90-day period after TKA were analyzed using multivariate Cox models, adjusting for patient demographic, morbidity, and institutional factors. In addition, hospital charges and payments were compared from primary surgery through subsequent 90 days. RESULTS: Morbidly obese patients showed a significantly elevated risk in most complications examined, with a 2-fold or higher risk in dislocation and wound dehiscence. In addition, death, periprosthetic joint infection, acute renal failure, and knee revision had significant hazard ratios between 1.5 and 2.0. However, risk of deep vein thrombosis and acute myocardial infarction did not increase for the morbidly obese patients. Superobese patients had significant increase in risk of infection, wound dehiscence, acute renal failures, revisions, death, and readmission compared with patients with BMI 40-49 kg/m(2). Significant dose-response trend was found between the level of BMI and risk for death, dislocation, implant failure, infection, readmission, revision, wound dehiscence, and acute renal failure. Controlling for patient and institutional factors, each TKA had an average total hospital charges of $75,884 among superobese patients, compared to $65,118 for the control group, a difference of $10,767. Medicare payment for the superobese patients was also higher, but only by $2703. CONCLUSION: Morbidly obese patients pose a significantly higher risk profile than normal-weight patients in a broad range of complications after TKA. Superobese patients add another layer of risk compared with less obese patients and are considerably more expensive to treat by health care systems. Technical difficulties and the high demand on resources present a severe challenge for providing treatment for such patients.