Acquired Idiopathic Stiffness After Contemporary Total Knee Arthroplasty: Incidence,Risk Factors,and Results Over 25 Years

BackgroundAcquired idiopathic stiffness (AIS) remains a common failure mode of contemporary total knee arthroplasties (TKAs). The present study investigated the incidence of AIS and manipulation under anesthesia (MUA) at a single institution over time, determined outcomes of MUAs, and identified risk factors associated with AIS and MUA.MethodsWe identified 9771 patients (12,735 knees) who underwent primary TKAs with cemented, modular metal-backed, posterior-stabilized implants from 2000 to 2016 using our institutional total joint registry. Mean age was 68 years, 57% were female, and mean body mass index was 33 kg/m². Demographic, surgical, and comorbidity data were investigated via univariate Cox proportional hazard models and fit to an adjusted multivariate model to access risk for AIS and MUA. Mean follow-up was 7 years.ResultsDuring the study period, 456 knees (3.6%) developed AIS and 336 knees (2.6%) underwent MUA. Range of motion (ROM) increased a mean of 34° after the MUA; however, ROM for patients treated with MUA was inferior to patients without AIS at final follow-up (102° vs 116°, P < .0001). Significant risk factors included younger age (HR 2.3, P < .001), increased tourniquet time (HR 1.01, P < .001), general anesthesia (HR 1.3, P = .007), and diabetes (HR 1.5, P = .001).ConclusionAcquired idiopathic stiffness has continued to have an important adverse impact on the outcomes of a subset of patients undergoing primary TKAs. When utilized, MUA improved mean ROM by 34°, but patients treated with MUA still had decreased ROM compared to patients without AIS. Importantly, we identified several significant risk factors associated with AIS and subsequent MUA.Level of EvidenceLevel III, retrospective comparative study.     

Autogenous Arteriovenous Bundle Implantation Maintains Viability Without Increased Immune Response in Large Porcine Bone Allotransplants

BackgroundTransplantation of living allogeneic bone segments may permit reconstruction of large defects, particularly if viability is maintained without immunosuppression. Development of a new autogenous osseous blood supply accomplishes this goal in rodent experimental models. This study evaluates potential systemic and local inflammatory responses to this angiogenesis in a large-animal model.MethodsVascularized allogeneic tibia segments were transplanted orthotopically into matched tibial defects in Yucatan minipigs. Microvascular anastomoses of bone nutrient artery and vein were supplemented by intramedullary placement of an autogenous arteriovenous (AV) bundle in group 1. Group 2 served as a no-angiogenesis control. A 3-drug immunosuppression regimen was withdrawn after 2 weeks. During the 20-week survival period, periodic leukocyte counts and inflammatory cytokine levels were measured. Thereafter, osteocyte survival was quantified and transplant rejection graded by histologic examination and quantitative real-time polymerase chain reaction of immunologic markers.ResultsBoth groups developed an initial systemic response, which resolved after 4 to 6 weeks. No differences were seen in blood cytokine levels. Interleukin 2 expression was diminished in group 1 tibiae. As expected, nutrient pedicles had thrombosed without sustained immunosuppression, occluded by intimal hyperplasia. In group 1, angiogenesis from the autogenous AV bundle resulted in significantly less osteonecrosis (P = .04) and fibrosis (P = .02) than group 2 allotransplants.ConclusionsSystemic immune responses to large-bone allotransplants were not increased by generation of an autogenous osseous blood supply within porcine tibial bone allotransplants. Implanted AV bundles diminished inflammation and fibrosis and improved bone viability when compared to no-angiogenesis controls.     

Opportunistic Infections After Induction With Alemtuzumab or Basiliximab: A 3-Year Kidney Transplantation Experience

BackgroundAntibody induction immunosuppression is commonly used in kidney transplantation to decrease the risk of early acute rejection. However, infectious complications may arise in patients treated with higher intensity induction immunosuppression. In this study, we compared the rate of opportunistic infections during the 3 years after kidney transplantation in recipients who received either alemtuzumab or basiliximab for induction therapy.MethodsAll renal transplant recipients from our center who received induction with alemtuzumab between 2011 and 2016 were included and matched 1:2 (by age and date of transplant) to renal transplant recipients who received basiliximab. The primary outcome was the rate of opportunistic infections.ResultsTwenty-seven patients received alemtuzumab (mean age = 50.8 years; SD ±12), and 54 received basiliximab (mean age = 50.8 years; SD ±11.8). Infections within 3 years posttransplant were not different between groups: BK viremia (P = .99), BK nephritis (P = .48), cytomegalovirus infection (P = .13), varicella zoster virus (P = .22), and all infections (P = .87). Time to infection (P = .67), patient survival (P = .21), and time to rejection (P = .098) were similar in both groups. There were also no group differences in delayed graft function (P = .76), graft loss (P = .97), or rejection (P = .2).ConclusionThe rate of infection was not significantly increased in recipients receiving lymphocyte-depleting alemtuzumab compared to recipients receiving basiliximab induction therapy, despite receiving similar maintenance immunosuppression. Although the immunologic risks differed between the 2 groups, there was no observable difference in clinical outcomes.     

Microscopic Wegener's disease: a particular form of Wegener's granulomatosis

We describe a case of Wegener's granulomatosis in which the disease was manifested with crescentic glomerulonephritis, upper airway ulcerations, and microangiopathic hemolytic anemia with consumptive coagulopathy. No granuloma was identified but antibodies to cytoplasmic components of neutrophils were strongly positive with a diffuse pattern. Because microscopic vessels were predominantly involved (capillaritis), and granuloma were absent, were refer to this particular form of the disease as "microscopic Wegener's disease."     

Clinical Concept-Based Radiology Reports Classification Pipeline for Lung Carcinoma

Rising incidence and mortality of cancer have led to an incremental amount of research in the field. To learn from preexisting data, it has become important to capture maximum information related to disease type, stage, treatment, and outcomes. Medical imaging reports are rich in this kind of information but are only present as free text. The extraction of information from such unstructured text reports is labor-intensive. The use of Natural Language Processing (NLP) tools to extract information from radiology reports can make it less time-consuming as well as more effective. In this study, we have developed and compared different models for the classification of lung carcinoma reports using clinical concepts. This study was approved by the institutional ethics committee as a retrospective study with a waiver of informed consent. A clinical concept-based classification pipeline for lung carcinoma radiology reports was developed using rule-based as well as machine learning models and compared. The machine learning models used were XGBoost and two more deep learning model architectures with bidirectional long short-term neural networks. A corpus consisting of 1700 radiology reports including computed tomography (CT) and positron emission tomography/computed tomography (PET/CT) reports were used for development and testing. Five hundred one radiology reports from MIMIC-III Clinical Database version 1.4 was used for external validation. The pipeline achieved an overall F1 score of 0.94 on the internal set and 0.74 on external validation with the rule-based algorithm using expert input giving the best performance. Among the machine learning models, the Bi-LSTM_dropout model performed better than the ML model using XGBoost and the Bi-LSTM_simple model on internal set, whereas on external validation, the Bi-LSTM_simple model performed relatively better than other 2. This pipeline can be used for clinical concept-based classification of radiology reports related to lung carcinoma from a huge corpus and also for automated annotation of these reports.

     

Disease type-associated increases of the plasma levels and ligand expression for natural alpha- or beta-galactoside-binding immunoglobulin G subfractions in patients with lung cancer

The presence of natural carbohydrate-binding antibodies may play a role in host defence against malignant cells in addition to elicitation of an immune response by artificial carbohydrate antigens. Human serum contains immunoglobulin G(2) (IgG) fractions with selectivity to alpha- and to beta-galactosides, respectively, irrespective of the type of blood group of the donor. To determine whether these naturally occurring subfractions may have any relevance for tumor disease control, their binding to malignant cells was ascertained by cytofluorimetric assays in vitro with a number of human tumor cell lines of different histogenetic origin. The affinity of cell binding was comparable to that of binding to lactosylated or melibiosylated neoglycoconjugates as model ligands in solid-phase assays and K-D values were found to be in the range of 5-300 nM. Cross-reactivity of the anomer-selective subfractions to the other type of ligand was observed to be rather low. When the IgG contents of plasma samples of patients with diverse types of lung cancer were assessed, the concentrations of both galactoside-binding immunoglobulin G subfractions were significantly increased in association with presence of small cell lung carcinoma and of metastatic lesions to the lung without any marked change in the overall IgG plasma level. Such an apparently general enhancement was seen for patients with adenocarcinoma and included both subfractions with no impact on their percentage in the total IEC content. When detergent extracts of tumor and tumor-free specimens of the same patient were analyzed with the affinity purified antibody subfractions to comparatively determine ligand presentation, increases in sugar-inhibitable binding were especially noted for the tumor tissue of small cell lung carcinomas and apparently tumor-free samples of cases with lung metastasis. Material from other types of lung cancer revealed no significant indication for disease-related alterations with the exception of carcinoids. These data demonstrate that plasma levels and ligand expression for two types of natural galactoside-binding immunoglobulin G fractions can show nonuniform responses in patients within the class of lung cancer. They encourage to deliberately monitor these parameters of the natural carbohydrate-directed antibody fractions in cancer patients with various types of disease to clarify the clinical significance of respective malignancy-associated changes.     

Full-Face Laser Resurfacing and Rhytidectomy

The Ultrapulse CO₂ laser (Coherent Inc., Palo Alto, CA, USA) was used in 239 patients, from March 1996 to July 1998, for full-face laser resurfacing. In 106 (43%) of these patients rhytidectomy was performed in the same procedure. All patients submitted to laser resurfacing were prepared for 1 to 2 months beforehand with retinoic acid and hydroquinone. The procedures were done under local anesthesia controlled by an anesthesiologist. A clear film dressing impregnated with silicone gel (Silon TSR; Bio-Med Sciences, Bethlehem, PA, USA) was used for 6 to 7 days and complete healing was observed in 7 to 10 days. Complications were exclusively dermatologic, without relation to surgery. No necrosis of the cutaneous flap was observed. Skin biopsies of 10 consecutive patients undergoing the combined procedures revealed no vascular impairment to the dermis. The patients were able to resume their activities 2 weeks after the procedure.     

The minimum sum of absolute errors regression: a robust alternative to the least squares regression.

This paper concerns the minimum sum of absolute errors regression. It is a more robust alternative to the popular least squares regression whenever there are outliers in the values of the response variable, or the errors follow a long tailed distribution, or the loss function is proportional to the absolute errors rather than their squared values. We use data from a study of interstitial lung disease to illustrate the method, interpret the findings, and contrast with least squares regression. We point out some of the problems with the least squares analysis and show how to avoid these with the minimum sum of absolute errors analysis.