The Center for Medicare and Medicaid Services (CMS) is faced with a challenge of decreasing the cost of care for total knee arthroplasty (TKA), but must make efforts to prevent patient selection bias in the process. Currently, no appropriate modifier codes exist for primary TKA based on case complexity. We sought to determine differences in perioperative parameters for patients with “complex” primary TKA with the hypothesis that they would require increased cost of care, prolonged care times, and have worse postoperative outcome metrics. We performed a single center retrospective review from 2015 to 2018 of all primary TKA. Patient demographics, medial proximal tibial angle (mPTA), lateral distal femoral angle (lDFA), flexion contracture, cost of care, and early postoperative outcomes were collected. ‘Complex’ patients were defined as those requiring stems or augments, and multivariable logistic regression analysis and propensity score matching were performed to evaluate perioperative outcomes.Introduction
Methods
Diagnosing fracture related infections (FRI) based on clinical symptoms alone can be challenging and additional diagnostic tools such as serum inflammatory markers are often utilized. The aims of this study were 1) to determine the individual diagnostic performance of three commonly used serum inflammatory markers: C-Reactive Protein (CRP), Leukocyte Count (LC) and Erythrocyte Sedimentation Rate (ESR), and 2) to determine the diagnostic performance of a combination of these markers and their value additionally to clinical predictors for FRI. This cohort study included patients who presented with a suspected FRI at two level I academic trauma centers between February 1st 2009 and December 31st 2017. The parameters CRP, LC and ESR, were obtained from hospital records when FRI was suspected. The gold standard for diagnosing or ruling out FRI was defined as: positive microbiology results of surgically obtained tissue samples, or absence of FRI at a clinical follow-up of at least six months. Separate markers were analysed using hospital thresholds, to determine current diagnostic performance, and continuously, to determine maximum possible diagnostic performance. Multivariable logistic regression analyses were performed to obtain the discriminative performance (Area Under the Receiver Operating Characteristic, AUROC) of (1) the combined inflammatory markers, and (2) the value of these markers additional to clinical parameters.Aim
Method
Diagnosing Fracture-Related Infections (FRI) is challenging. White blood cell (WBC) scintigraphy is considered the best nuclear imaging technique to diagnose FRI; a recent study by our group found a diagnostic accuracy of 92%. However, many centers use 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) which has several logistic advantages. Whether 18F-FDG-PET/CT has better diagnostic performance than white blood cell (WBC) scintigraphy is uncertain. Therefore, we aimed: 1) to determine the diagnostic performance of 18F-FDG-PET/CT for diagnosing FRI (defined as infection following an open fracture or fracture surgery) and 2) to determine cut-off values of standardized uptake values (SUV) that result in optimal diagnostic performance. This retrospective cohort study included all consecutive patients who received 18F-FDG-PET/CT to diagnose FRI in two level 1 trauma centers. Baseline demographic- and surgical characteristics were retrospectively reviewed. The reference standard consisted of at least 2 representative microbiological culture results or the presence or absence of clinical confirmatory FRI signs in at least 6 months of clinical follow-up. A nuclear medicine specialist, blinded to the reference standard, re-reviewed all scans. Additionally, SUVs were measured using the “European Association of Nuclear Medicine Research Ltd. (EARL)” reconstructed 18F-FDG-PET/CT scans. Volume of interests were drawn around the suspected- and corresponding contralateral area to obtain the absolute values (SUVmax) and the ratio between suspected and contralateral area (SUVratio). Diagnostic accuracy of the re-reviewed scans was calculated (sensitivity and specificity). Additionally, diagnostic characteristics of the SUV measurements were plotted in the area under the receiver operating characteristics curve (AUROC). The sensitivity and specificity at the optimal threshold was deducted from the AUROC with the Q-point method.Aim
Method
Fracture related infection (FRI) remains a challenging diagnosis in orthopedic and trauma surgery. In addition to clinical signs and imaging, serum inflammatory markers are often used to estimate the probability of FRI. To what extent serum inflammatory markers can be used to rule out and diagnose FRI remains unclear. The aim of this systematic review was to assess the diagnostic value of the serum inflammatory markers C-reactive protein (CRP), leukocyte count (LC) and erythrocyte sedimentation rate (ESR) in suspected fracture related infection. PubMed, Embase and Cochrane databases were searched for all articles focusing on the diagnostic value of CRP, LC and ESR in FRI. Studies on other inflammatory markers or other types of orthopedic infection, such as periprosthetic and diabetic foot infections, were excluded. For each serum inflammatory marker, all reported sensitivity and specificity combinations were extracted and graphically visualized. Average estimates were obtained using bivariate mixed effects models. This study utilized the QUADAS-2 criteria and was reported following the PRISMA statement.Aim
Method
Vitamin D deficiency is common in patients undergoing total hip (THA) or total knee arthroplasty (TKA) which may affect prosthesis survival and 90-day readmission rates. The purpose of this study was to assess whether preoperative Vitamin D deficiency or insufficiency have an influence on revision, readmission, and complication rates following THA and TKA. We hypothesized that low Vitamin D levels in patients undergoing THA and TKA have a negative effect on revision rates. Patients who underwent primary THA or TKA in a 2-year period university hospital were identified and stratified into 3 groups based on preoperative 25-hydroxyvitamin D serum levels: normal levels of 30 ng/ml or greater, (2) deficient levels of 20–29.9 ng/ml, and (3) insufficient levels of less than 20 ng/ml. Patient demographics and postoperative course were collected from the electronic medical record.Introduction
Methods
Arthrofibrosis following total knee arthroplasty (TKA) is a complex and multifactorial complication that may require manipulation under anesthesia (MUA). However, patient and surgical factors that potentially influence the development of knee stiffness following TKA are not fully understood. The purpose of this study was to identify patient and surgical factors that may influence arthrofibrosis following TKA by assessing a cohort of patient that underwent MUA and comparing them to a matched cohort of patients without arthrofibrosis. The joints registry of a university hospital was searched for patient that underwent MUA following primary TKA between 2004 and 2013. Demographic and surgical information was obtained from the electronic medical record including range of motion (ROM), comorbidities and timing of MUA. Patients who underwent MUA were then double-matched by baseline (prior to primary TKA) knee ROM to patients who underwent primary TKA without postoperative arthrofibrosis during the same time period.Introduction
Methods
The number of complex revision total hip arthroplasties (THA) is predicted to rise. The identification of acetabular bone defects prior to revision THA has important implications on technique and complexity of acetabular reconstruction. Paprosky et al. proposed a classification system including 3 main types with up to 3 subtypes focused on the integrity of the superior rim of the acetabulum and medial wall. However, the classification system is complex and its reliability has been questioned. The purpose of this study was to evaluate the effectiveness of different radiologic imaging modalities (plain radiographs, 2-D CT, 3-D CT reconstructions) in classifying acetabular defects in revision hip arthroplasty cases and their value of at different levels of orthopaedic training. Patients treated with revision total hip arthroplasty for acetabular bone defects between 2002–2012 were identified and 22 cases selected that had plain radiographs, 2-D CT and 3-D reconstructions available. Bone defects were classified independently by two fellowship-trained adult reconstruction surgeons. Representative sections were chosen and compiled into a timed presentation. Thirty-five residents from PGY-1 to PGY-5 and 4 attending orthopaedic surgeons were recruited for this study and received a 15-minute introduction to the classification system. Chi square analysis was utilized to examine the influence of image modality and level of training on the correct classification of acetabular bone loss using the Paprosky classification system with alpha=0.05.Introduction
Methods
Fifteen to twenty percent of patients presenting for total hip arthroplasty (THA) have bilateral disease. While simultaneous bilateral THA is of interest to patients and surgeons, debate persists regarding its merits. The majority of previous reports on simultaneous bilateral THA involve patients in the lateral decubitus position, which require repositioning, prepping and draping, and exposure of a fresh wound to pressure and manipulation for the contralateral THA. The purpose of this study was to compare complications, component position, and financial parameters for simultaneous versus staged bilateral THAs using the direct anterior approach (DAA). Medical records were reviewed for patient demographics, medical history, operative time, estimated blood loss (EBL), change in hemoglobin, transfusion, tranexamic acid (TXA) use, length of stay (LOS), discharge disposition, leg length discrepancy, acetabular cup position, and perioperative complications. Cost and reimbursement data were analyzed.Background
Methods
Unicompartmental knee arthroplasty (UKA) has seen renewed interest in recent years and is a viable option for patients with limited degenerative disease of the knee as an alternative to total knee arthroplasty. However, the minimally invasive UKA procedure is challenging, and accurate component alignment is vital to long-term survival. Robotic-assisted UKA allows for greater accuracy of component placement and dynamic intraoperative ligament balancing which may improve clinical patient outcomes. The purpose of this study was to analyse the clinical outcomes in a large, consecutive cohort of patients that underwent robotic-assisted UKA at a single institution with a minimum follow-up of 2 years. The study hypothesis was that robotic-assisted UKA improves patient outcomes by decreasing the rate of revision in comparison to conventional UKA. A search of the institutional joint registry was performed to identify patients that underwent robotic-assisted UKA beginning in August 2008. The patients' electronic medical record was analysed for surgical indication, age at surgery, body mass index (BMI), and American Society of Anesthesiology Physical Status Classification System (ASA). Patient comorbidities were evaluated using the Charlson comorbidity index. Length of surgery and length of hospitalisation were assessed and clinical outcomes were evaluated using the Oxford Knee Score. In addition to postoperative follow-up assessments in clinic, patients without recent follow-up were contacted by telephone to capture the overall revision rate and time to revision.Introduction
Materials and methods
Unicompartmental knee arthroplasty (UKA) has seen renewed interest in recent years due to improved surgical techniques and prosthetic design, and the desire for minimally invasive surgery. For patients with limited degenerative disease, UKA offers a viable alternative to total knee arthroplasty. Historically, the outcomes of lateral compartment UKA have been inferior to medial compartment UKA, with suboptimal patient satisfaction and increased revision rates. Robotic-assisted UKA has been shown to improve precision and accuracy of component placement, which may improve outcomes of lateral UKA. The purpose of this study was to compare the outcome of robotic-assisted UKA to conventional UKA for degenerative disease of the lateral compartment. The hypothesis of the study was that robotic-assisted lateral UKA results in superior outcomes compared to conventional UKA. A search of the institution's joint registry was conducted to identify patients who underwent UKA for limited degenerative disease of the lateral knee compartment. A total of 130 lateral UKAs were identified that were performed between 2004 and 2012. The mean age of the patients was 63.1 years (range, 20 to 88); patients had a mean BMI of 29.9 (range, 18 to 48). The medical records of all patients were reviewed and assessed for the type of surgical procedure used (robotic-assisted versus conventional), length of hospital stay, Oxford knee score, and occurrence of revision surgery.Introduction
Materials and methods
