Causes of Revision of Total Knee Arthroplasties in a Tertiary Hospital in Brazil.

 To identify the causes of revision of total knee arthroplasty in a referral center in Brazil.  This is a case series, with 80 patients undergoing revision surgery for total knee arthroplasty (RTKA) at a referral center for knee surgery, between August 2019 and November 2021, with a mean age of 69.6 years.

Equal rates of bone healing and reduced surgical time with iliac crest allograft compared to autograft in medial opening wedge high tibial osteotomy: a randomized controlled clinical trial.

Introduction: Iliac crest autograft is frequently used to fill in bone defects after osteotomies. Nonetheless, surgery for bone autograft procurement is associated with morbidity and pain at the donor site. Alternatives to it have been explored, but there is no consensus to guide their application as a routine practice in several orthopedic procedures.

Synovial fluid NMR-based metabolomics in septic and aseptic revision total knee arthroplasty: Implications on diagnosis and treatment.

Periprosthetic joint infection (PJI) is one of the most challenging complications following total knee arthroplasty. Despite its importance, there is a paucity of reports in the literature regarding its pathogenesis. Recently, cellular metabolic reprogramming has been shown to play an important role in the progression and outcome of infectious diseases.

Accuracy of Serological Markers, Synovial Fluid, Microbiological Culture, and Histopathological Examination for Diagnosing Periprosthetic Knee Infection.

 This study assessed the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of serological tests, synovial fluid markers, microbiological tissue culture, and histopathological examination of the periprosthetic membrane in diagnosing periprosthetic knee infection.  This study is prospective, and it includes patients undergoing total knee arthroplasty revision surgery from November 2019 to December 2021. The analysis consisted of serological tests (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], and D-dimer), synovial fluid markers (leukocyte and polymorphonuclear cell counts), periprosthetic tissue culture, and histopathological examination of the periprosthetic membrane of all patients.

Microbiological Profile of Periprosthetic Knee Infections in a Brazilian Unified Health System Hospital Specialized in Highly Complex Orthopedic Surgeries.

 We studied the microbiological profile of periprosthetic knee infections treated in a Brazilian tertiary hospital.  The study included all patients undergoing revision surgery for total knee arthroplasty (RTKA) between November 2019 and December 2021, with a diagnosis of periprosthetic infection confirmed per the 2018 International Consensus Meeting (ICM) criteria.  Sixty-two patients had a periprosthetic joint infection (PJI) per the 2018 ICM criteria.

Midterm Radiographic Results and Reoperations of Tantalum Trabecular Metal Cones in Knee Arthroplasties.

 The management of bone loss represents a challenge in revisions of total knee arthroplasty (rTKA) and in complex primary total knee arthroplasties (TKAs). The purpose of the present study was to evaluate the midterm outcomes (5-year minimum follow-up) of knee reconstructions with tantalum trabecular metal (TM) cones on bone defects Anderson Orthopaedics Research Institute (AORI) 2 and 3.  A retrospective analysis of the medical records of patients operated on between July 2008 and November 2014 was performed, collecting the following data: age, gender, laterality, body mass index, etiology of arthrosis, comorbidities, AORI classification of bone defects, causes for revision, readmissions, reoperations, perioperative and postoperative complications, radiographic signs of osteointegration, and maintenance of the TM support.

EXTENSOR MECHANISM TRANSPLANTATION AFTER KNEE PROSTHESIS: 70-MONTH FOLLOW-UP.

Objective: This article reports the range of motion, failure rate, and complications of patients with extensor mechanism injury after total knee arthroplasty (TKA) treated with extensor mechanism allograft with mid-term follow-up.

Methods: Patients undergoing post-ATJ extensor mechanism transplantation from 2009 to 2018 were retrospectively evaluated. Demographics, the reason for transplantation, elapsed time from arthroplasty to transplantation, related surgical factors, immobilization time, range of motion, transplant failure, and complications were collected.

Infection after primary total knee arthroplasty: a randomized controlled prospective study of the addition of antibiotics to bone cement.

 The present prospective, randomized and controlled study was conducted with 286 patients submitted to primary total knee arthroplasty (TKA) with the objective of evaluating the efficacy of the addition of antibiotics to bone cement as a way to prevent post arthroplasty infection (PAI).  The patients were randomized into two groups: bone cement without antibiotic (No ATB, = 158) or cement with antibiotic (ATB, = 128), in which 2 g of vancomycin was added to 40 g of cement. The patients were followed up for 24 months after surgery.

Predictive Factors for Blood Transfusion after Total Knee Arthroplasty.

 The present paper aims to (1) verify the incidence and volume of blood transfusion among patients undergoing unilateral cemented total knee arthroplasty (TKA) in a single Brazilian reference center; (2) identify pre and perioperative variables to determine subjects with higher risk (i.e., predictive factors) for blood transfusion within 48 hours following surgery; (3) estimate the risk of blood transfusion during the first 48 hours after the procedure.

Bone Defects in Revision Total Knee Arthroplasty.

The increase in the number of revision total knee arthroplasty surgeries has been observed in recent years, worldwide, for several causes. In the United States, a 601% increase in the number of total knee arthroplasties, between 2005 and 2030, is estimated. Among the enormous challenges of this complex surgery, the adequate treatment of bone defects is essential to obtain satisfactory and lasting results.

Surgical Treatment of Chronic Rupture of the Quadriceps Using a Modified Pulvertaft Weave Technique.

The extensor mechanism provides active knee joint extension and stability of the patellofemoral joint. Rupture of the quadriceps tendon, although uncommon, is therefore associated with impairment in knee joint stability and, thus, requires surgical repair. Although various techniques provide excellent clinical outcomes for acute rupture, treatment of chronic rupture remains clinically challenging.

LATE EVALUATION OF PATIENTS UNDERGOING MANIPULATION OF THE KNEE AFTER TOTAL ARTHROPLASTY.

Objective: We compared gains in range of motion in patients who underwent manipulation within 12 weeks of total knee arthroplasty (TKA) and after this period. We also evaluated maintenance of the arc obtained from knee manipulation in late follow-up, along with factors associated with poorer outcomes.

Method: The study was divided into two groups according to the time after TKA; the surgeries took place between January 2008 and December 2014.

Distal femoral cut in total knee arthroplasty in a Brazilian population.

Objective: To determine the ideal angle for making the distal femoral cut in total knee arthroplasty in a Brazilian population.

Methods: Panoramic radiographs of the lower limbs bearing weight from 79 patients (57 women and 22 men) were studied, totaling 107 knees with an indication for total knee arthroplasty. The femoral anatomical axis, femoral mechanical axis and cervical-diaphyseal angle were traced out.

Tumor formation in Hoffa's infrapatellar fat: Case report.

Although tumors or pseudotumoral lesions are rare in the infrapatellar fat, they may affect it. Osteochondroma is the commonest benign bone tumor. However, extraskeletal presentations are rare.

Femoropatellar radiographic alterations in cases of anterior cruciate ligament failure.

Objective: To make a comparative analysis on three femoropatellar radiographic parameters, between knees with chronic failure of the anterior cruciate ligament (ACL) and normal knees.

Methods: Thirty volunteer patients with a diagnosis of unilateral isolated chronic ACL injury for more than one year and a normal contralateral knee were selected. Digital radiographs were produced for all the patients, on both knees in absolute lateral view at 30° of flexion, with and without load-bearing on one leg, and in axial view of the patella at 30°.

Amputation after failure or complication of total knee arthroplasty: prevalence, etiology and functional outcomes.

Objective: Identify the etiology and incidence, as well to assess functional outcomes of patients, undergoing lower limb amputation after failure or complication of total knee arthroplasty. These patients were treated at the Center for Knee Surgery at the National Institute of Traumatology and Orthopedics (INTO), during the period of January 2001 to December 2010.

Methods: The patients were interviewed and their charts were retrospectively analyzed to evaluate their functional outcome.

Homologous structural graft for treatment of bone defect during knee revision arthroplasty.

Obtaining stable bone-implant interface, correct alignment of the components, proper balance of soft tissues' tension, maintenance of proper joint interline are fundamental principles for success in surgical revision total knee arthroplasty, which are only obtained with management bone deficiency. However, proper treatment of large defects remains unclear. The aim of this study was to evaluate the clinical and radiographic results of patients that had underwent revision surgery for total knee arthroplasty with use of structural grafts of musculoskeletal tissue bank in the period between January 2002 to December 2010 by the Knee Surgery Center of National Institute of Traumatology and Orthopaedics (INTO).

ASSESSMENT OF TIBIAL SLOPE ANGLE AND PATELLAR HEIGHT AFTER MEDIAL-OPENING TIBIAL OSTEOTOMY.

Objective: To measure the variation in posterior tibial slope angle and patellar height in patients who underwent proximal tibial valgus-producing osteotomy using the medial-opening wedge technique.

Methods: Anteroposterior panoramic radiographs of the lower limbs and lateral radiographs of the knee obtained before and after tibial valgus-producing osteotomy on 46 patients with unicompartmental arthrosis of the knee were analyzed.

Results: In 23 patients, an external fixator was used to gradually apply a medial-opening wedge; and in the other 23, a blocked plate with a stop bar was applied as a fixation method.

MOBILE TIBIAL POLYETHYLENE BEARING IN TOTAL KNEE ARTHROPLASTY.

Debris of polyethylene tibial bearings have been recognized as a major cause for the onset of the cascade of biological events leading to osteolysis and loosening of prosthetic components after total knee arthroplasty. Since then, research has been focused on alternative bearing surfaces in order to minimize the amount and rate of polyethylene wear off and, in doing so, increasing the survivorship rate for knee arthroplasties. One such option is to have a mobile tibial bearing allowing more conformity and rotational self-alignment of the components, improving kinetics and kinematics of the prosthesis.