A new mini-navigation tool allows accurate component placement during anterior total hip arthroplasty.

Introduction: Computer-assisted navigation systems have been explored in total hip arthroplasty (THA) to improve component positioning. While these systems traditionally rely on anterior pelvic plane registration, variances in soft tissue thickness overlying anatomical landmarks can lead to registration error, and the supine coronal plane has instead been proposed. The purpose of this study was to evaluate the accuracy of a novel navigation tool, using registration of the anterior pelvic plane or supine coronal plane during simulated anterior THA. Methods: Measurements regarding the acetabular component position, and changes in leg length and offset were recorded. Benchtop phantoms and target measurement values commonly seen in surgery were used for analysis. Measurements for anteversion and inclination, and changes in leg length and offset were recorded by the navigation tool and compared with the known target value of the simulation. Pearson\u27s Results: The device accurately measured cup position and leg length measurements to within 1° and 1 mm of the known target values, respectively. Across all simulations, there was a strong, positive relationship between values obtained by the device and the known target values ( Conclusion: The preliminary findings of this study suggest that the novel navigation tool tested is a potentially viable tool to improve the accuracy of component placement during THA using the anterior approach

The impact of patellar resurfacing in two-stage revision of the infected total knee arthroplasty.

Evidence for optimal management of the patellofemoral joint in revision surgery for the infected TKA is limited. We reviewed 69 infected TKAs undergoing two-stage revision. Fifty four patellae were resurfaced, 11 had patelloplasty performed, two were augmented with trabecular metal, one had impaction grafting, and one knee underwent patellectomy. Average follow-up was 4.5years. The patients that received patellar resurfacing at re-implantation experienced statistically significant improvements in KSS pain score, functional KSS, and patellar score (

Biological response to prosthetic debris.

Joint arthroplasty had revolutionized the outcome of orthopaedic surgery. Extensive and collaborative work of many innovator surgeons had led to the development of durable bearing surfaces, yet no single material is considered absolutely perfect. Generation of wear debris from any part of the prosthesis is unavoidable. Implant loosening secondary to osteolysis is the most common mode of failure of arthroplasty. Osteolysis is the resultant of complex contribution of the generated wear debris and the mechanical instability of the prosthetic components. Roughly speaking, all orthopedic biomaterials may induce a universal biologic host response to generated wear débris with little specific characteristics for each material; but some debris has been shown to be more cytotoxic than others. Prosthetic wear debris induces an extensive biological cascade of adverse cellular responses, where macrophages are the main cellular type involved in this hostile inflammatory process. Macrophages cause osteolysis indirectly by releasing numerous chemotactic inflammatory mediators, and directly by resorbing bone with their membrane microstructures. The bio-reactivity of wear particles depends on two major elements: particle characteristics (size, concentration and composition) and host characteristics. While any particle type may enhance hostile cellular reaction, cytological examination demonstrated that more than 70% of the debris burden is constituted of polyethylene particles. Comprehensive understanding of the intricate process of osteolysis is of utmost importance for future development of therapeutic modalities that may delay or prevent the disease progression

Molecular diagnostics in periprosthetic joint infection.

Periprosthetic joint infection (PJI) is a significant and costly challenge to the orthopedic community. The lack of a gold standard for diagnosis remains the biggest obstacle in the detection and subsequent treatment of PJI. Molecular markers in the serum and joint fluid aspirate hold immense promise to enhance the development of a firm diagnostic criterion. The primary goal is one marker with high sensitivity and specificity. Here, we review our current research efforts in the field of molecular markers: C-reactive protein, erythrocyte sedimentation rate, white blood cells, and leukocyte esterase. Each marker has been studied to determine its sensitivity, specificity, and positive and negative predictive values in diagnosing PJI

The infected hip: A treatment algorithm

The management of periprosthetic joint infection following total joint arthroplasty is presently a major challenge to orthopedic surgeons. Despite various treatment options available, the two-stage revision procedure is most often chosen in North America because of a high success rate, especially in cases involving resistant organisms. Sometimes the use of antibiotics alone, irrigation with debridement, or a one-stage exchange may be a more appropriate treatment option. Various factors such as the status of a patient’s immune system, time of onset of the infection, as well as susceptibility of causative microorganism should be considered as they play an important role in effectiveness of treatment. When surgery presents a great risk to patients due to their level of health, and infection is caused by a low-virulent antimicrobial susceptible pathogen, antibiotic suppression alone may be the best treatment option. If the patient can successfully undergo surgery then an irrigation and debridement procedure may be preferred, especially with an acute onset of symptoms. If onset of symptoms is much later as in chronic cases, or irrigation and debridement procedure is unsuccessful, then resection of all components and reimplantation is necessary. In a two-stage revision, placement of an antibiotic-loaded spacer is needed to eradicate the infection before reimplantation takes place. There are rare cases in which salvage procedures, such as arthrodesis or amputation, are necessary to completely eradicate an uncontrollable infection in immunocompromised patients

Prevention of infection and disruption of the pathogen transfer chain in elective surgery

The COVID-19 pandemic has caused us all to stop our normal activities and consider how we can safely return to caring for our patients. There are many common practices (such as an increased use of personal protective equipment) which we are all familiar with that can be easily incorporated into our daily routines. Other actions, such as cleaning more surfaces with solutions such as dilute povidone iodine or changing the air filtration systems used within operating room theaters, may require more extensive efforts on our behalf. In this article, we have attempted to highlight some of the changes that arthroplasty surgeons may need to instigate when we are able to resume elective joint arthroplasty procedures in an effort to disrupt the chain of pathogen transfer

Periprosthetic Knee Infection: Ten Strategies That Work.

Periprosthetic joint infection (PJI) is one of the most serious complications following total knee arthroplasty (TKA). The demand for TKA is rapidly increasing, resulting in a subsequent increase in infections involving knee prosthesis. Despite the existence of common management practices, the best approach for several aspects in the management of periprosthetic knee infection remains controversial. This review examines the current understanding in the management of the following aspects of PJI: preoperative risk stratification, preoperative antibiotics, preoperative skin preparation, outpatient diagnosis, assessing for infection in revision cases, improving culture utility, irrigation and debridement, one and two-stage revision, and patient prognostic information. Moreover, ten strategies for the management of periprosthetic knee infection based on available literature, and experience of the authors were reviewed

Which Osteotomy for Osteonecrosis of the Femoral Head and Which Patient for the Osteotomy?

Transtrochanteric curved varus osteotomy (TCVO) and transtrochanteric rotational osteotomy (TRO) are joint-preserving procedures for osteonecrosis of the femoral head. The purpose of this review is to provide up-to-date guidelines for the osteotomies. One retrospective comparison revealed that TCVO has shorter operation time, less bleeding, lower incidence of osteophyte formation, and lower rate of secondary collapse. To obtain successful results of the osteotomy, the patient should be younger than 40 years and should have a body mass index of less than 24 kg/m2. The osteotomy should be performed in early stages of femoral head osteonecrosis before marked collapse of the femoral head. The patient should have a medium-size lesion and an enough viable bone to restore the intact articular surface and subchondral bone in the weight-bearing area

Management of periprosthetic joint infection: the current knowledge: AAOS exhibit selection.

Periprosthetic joint infection continues to frustrate the medical community. Although the demand for total joint arthroplasty is increasing, the burden of such infections is increasing even more rapidly, and they pose a unique challenge because their accurate diagnosis and eradication can prove elusive. This review describes the current knowledge regarding diagnosis and treatment of periprosthetic joint infection. A number of tools are available to aid in establishing a diagnosis of periprosthetic joint infection. These include the erythrocyte sedimentation rate, serum C-reactive protein concentration, synovial white blood-cell count and differential, imaging studies, tissue specimen culturing, and histological analysis. Multiple definitions of periprosthetic joint infection have been proposed but there is no consensus. Tools under investigation to diagnose such infections include the C-reactive protein concentration in the joint fluid, point-of-care strip tests for the leukocyte esterase concentration in the joint fluid, and other molecular markers of periprosthetic joint infection. Treatment options include irrigation and debridement with prosthesis retention, one-stage prosthesis exchange, two-stage prosthesis exchange with intervening placement of an antibiotic-loaded spacer, and salvage treatments such as joint arthrodesis and amputation. Treatment selection is dependent on multiple factors including the timing of the symptom onset, patient health, the infecting organism, and a history of infection in the joint. Although prosthesis retention has the theoretical advantages of decreased morbidity and improved return to function, two-stage exchange provides a lower rate of recurrent infection. As the burden of periprosthetic joint infection increases, the orthopaedic and medical community should become more familiar with the disease. It is hoped that the tools currently under investigation will aid clinicians in diagnosing periprosthetic joint infection in an accurate and timely fashion to allow appropriate treatment. Given the current knowledge and planned future research, the medical community should be prepared to effectively manage this increasingly prevalent disease

Predictors of perioperative blood loss in total joint arthroplasty.

UNLABELLED: UPDATE The print version of this article has errors that have been corrected in the online version of this article. In the Materials and Methods section, the sentence that reads as During the study period, our institution offered preoperative autologous blood donation to all patients who were scheduling for total joint arthroplasty with a hemoglobin level of no less than 11 mg/dL or a hematocrit level of at least 33%. in the print version now reads as During the study period, our institution offered preoperative autologous blood donation to all patients who were scheduling for total joint arthroplasty with a hemoglobin level of no less than 11 g/dL or a hematocrit level of at least 33%. in the online version. In Table III, the footnote that reads as The values are given as the estimate and the standard error in milligrams per deciliter. in the print version now reads as The values are given as the estimate and the standard error in grams per deciliter. in the online version. BACKGROUND: Despite advances in surgical and anesthetic techniques, lower-extremity total joint arthroplasty is associated with considerable perioperative blood loss. As predictors of perioperative blood loss and allogenic blood transfusion have not yet been well defined, the purpose of this study was to identify clinical predictors for perioperative blood loss and allogenic blood transfusion in patients undergoing total joint arthroplasty. METHODS: From 2000 to 2008, all patients undergoing unilateral primary total hip or knee arthroplasty who met the inclusion criteria were enrolled in the study. Perioperative blood loss was calculated with use of a previously validated formula. The predictors of perioperative blood loss and allogenic blood transfusion were identified in a multivariate analysis. RESULTS: Eleven thousand three hundred and seventy-three patients who underwent total joint arthroplasty, including 4769 patients who underwent total knee arthroplasty and 6604 patients who underwent total hip arthroplasty, were evaluated. Multivariate analysis indicated that an increase in blood loss was associated with being male (263.59 mL in male patients who had undergone total hip arthroplasty and 233.60 mL in male patients who had undergone total knee arthroplasty), a Charlson Comorbidity Index of \u3e3 (293.99 mL in patients who had undergone total hip arthroplasty and 167.96 mL in patients who had undergone total knee arthroplasty), and preoperative autologous blood donation (593.51 mL in patients who had undergone total hip arthroplasty and 592.30 mL in patients who had undergone total knee arthroplasty). In patients who underwent total hip arthroplasty, regional anesthesia compared with general anesthesia reduced the amount of blood loss. The risk of allogenic blood transfusion increased with the amount of blood loss in the patients who underwent total hip arthroplasty (odds ratio, 1.43 [95% confidence interval, 1.40 to 1.46]) and the patients who underwent total knee arthroplasty (odds ratio, 1.47 [95% confidence interval, 1.42 to 1.51]), but the risk of blood transfusion increased with the Charlson Comorbidity Index only in patients who underwent total knee arthroplasty (odds ratio, 3.2 [95% confidence interval, 1.99 to 5.15]). The risk of allogenic blood transfusion decreased with preoperative autologous blood donation in patients who underwent total hip arthroplasty (odds ratio, 0.01 [95% confidence interval, 0.01 to 0.02]) and patients who underwent total knee arthroplasty (odds ratio, 0.02 [95% confidence interval, 0.01 to 0.03]). CONCLUSIONS: This study identified some clinical predictors for blood loss in patients undergoing total joint arthroplasty that we believe can be used for implementing more effective blood conservation strategies. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence