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Background Acetabular fractures often require surgical intervention for fracture fixation and can result in premature osteoarthritis of the hip joint. This study hypothesized that total hip arthroplasty (THA) in patients with a prior acetabular fracture who had undergone open reduction and internal fixation (ORIF) is associated with a higher rate of subsequent periprosthetic joint infection (PJI). Methods About 72 patients with a history of acetabular fracture that required ORIF, undergoing conversion THA between 2000 and 2017 at our institution, were matched based on age, gender, body mass index, Charlson comorbidity index, and date of surgery in a 1:3 ratio with 215 patients receiving primary THA. The mean follow-up for the conversion THA cohort was 2.9 years (range, 1-12.15) and 3.06 years (range, 1-12.96) for the primary THA. Results Patients with a previous acetabular fracture, compared with the primary THA patients, had longer operative times, greater operative blood loss, and an increased need for allogeneic blood transfusion (26.4% vs 4.7%). Most notably, PJI rate was significantly higher in acetabular fracture group at 6.9% compared with 0.5% in the control group. Complications, such as aseptic revision, venous thromboembolism, and mortality, were similar between both groups. Conclusion The present study demonstrates that conversion THA in patients with prior ORIF of acetabular fractures is associated with higher complication rate, in particular PJI, and less optimal outcome compared with patients undergoing primary THA. The latter findings compel us to seek and implement specific strategies that aim to reduce the risk of subsequent PJI in these patients.

Introduction: Periprosthetic joint infection (PJI) remains one of the most dreaded and challenging complications in adult reconstruction. While primary total joint arthroplasty is one of the most s...

BACKGROUND An overall assessment of how patient demographic characteristics and comorbidities are improving or worsening can allow better understanding of the value of revision total joint arthroplasty (TJA). Therefore, the purpose of this study was to identify patient demographic characteristics and comorbidities trends and episode-of-care outcome trends from 2008 to 2018 in patients undergoing revision TJA. METHODS The National Surgical Quality Improvement Program database was queried to identify patient demographic characteristics, comorbidities, and episode-of-care outcomes in patients undergoing revision TJA from 2008 to 2018 (n = 45,706). Pairwise t tests and pairwise chi-square tests were performed on consecutive years with Bonferroni correction. Trends were assessed using the 2-tailed Mann-Kendall test of the temporal trend. RESULTS Among patients undergoing revision TJA, there was no clinically important difference, from 2008 to 2018, in age, body mass index (BMI), percentages with >40 kg/m2 BMI, diabetes (18.8% to 19%), chronic obstructive pulmonary disease (4.1% to 5.4%), congestive heart failure within 30 days (0% to 1%), or acute renal failure (0% to 0.2%). However, modifiable comorbidities including smoking status (14.7% to 12.0%; p = 0.01), hypertension (66% to 26.0%; p = 0.02), anemia (34.5% to 26.3%; p < 0.001), malnutrition (10.4% to 9.3%; p = 0.004), and overall morbidity or mortality probability have improved, with a decrease in the hospital length of stay and 30-day readmission and a significant increase in home discharge (p < 0.001 for all). CONCLUSIONS Time-difference analysis demonstrated that the overall health status of patients undergoing revision TJA improved from 2008 to 2018. However, formal time-trend analysis demonstrated improvements to a lesser degree. The multidisciplinary effort to improve value-based metrics including patient comorbidity optimization and episode-of-care outcomes for primary TJA has been shown to potentially have an impact on revision TJA. LEVEL OF EVIDENCE Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background Direct anterior approach (DAA) total hip arthroplasty can be performed through a traditional vertical incision or a horizontal (bikini) incision. The purpose of this study is to compare the 2 approaches, performed by a single surgeon past the learning curve, in terms of (1) overall wound complications and (2) patient-reported esthetics at the 6-month follow-up. Methods A case-control retrospective study was conducted. Eighty-six bikini DAA patients were matched 3:1 to 230 conventional DAA patients for gender, age, body mass index (BMI), and American Society of Anesthesiologists score. Outcomes evaluated included wound complications, acute periprosthetic joint infection, transfusion, length of surgery, and dysesthesia. A subgroup analysis was also performed on obese patients, BMI greater than 30 kg/m2. Furthermore, the patients rated cosmesis of the incision at 6 months using a Patient Scar Assessment Scale and the Vancouver Scar Assessment Scale. Results Bikini patients had lower rates of delayed wound healing compared to conventional incision (2.3% vs 6.1%, P = .087). This difference was statistically significant (0% vs 16.6%, P Conclusion Our study demonstrates that the DAA total hip arthroplasty can be performed safely through an alternative horizontal bikini incision with complication rates equivalent to conventional incision DAA and to those in other approaches when performed by surgeons in a high volume, efficient hip replacement institution. In patients whose BMI is >30, a potential benefit of the horizontal incision may be lower wound complications. This study design should be performed at other institutions and ideally at a multi-institution level to evaluate if results can be corroborated. Our opinion is that the horizontal bikini incision should be utilized but only after mastery of the DAA approach using the conventional vertical incision.

CASE A 76-year-old man presented with metastatic renal cell carcinoma (RCC) in the right acetabulum with pelvic compromise. The patient had right hip pain and difficulty with ambulation, as such he elected to undergo tumor resection with subsequent reconstruction of pelvic defect. Given the size and location of the anticipated pelvic defect, robotic-assisted hip arthroplasty was used to execute prosthetic component placement and anatomic pelvic reconstruction. CONCLUSION Advances in technology, such as robotics and 3D navigation, have application in orthopaedic oncology surgery, especially for reconstructions after pelvic resections. The goal of this case report is to describe the utility of this technology in a case of metastatic RCC.

Background Although periprosthetic joint infection (PJI) can affect multiple joints concurrently, the majority of patients with multiple prosthetic joints present with PJI of a single joint. Data regarding the optimal management of these patients are limited. We aimed to identify the prevalence, risk factors for a subsequent PJI, and clinical circumstances of PJI in patients with multiple prosthetic joints. Methods We retrospectively reviewed the clinical records of 197 patients with ≥2 total joint prostheses in place who presented with PJI from 2000 to 2017. The average follow-up was 3.6 years (range, 0.5 to 17 years). Demographic data and risk factors for synchronous or metachronous PJI were identified. The time from the initial to the second PJI and organism profile data were collected as well. The workup for other joints with a prosthesis in place at the time of the initial PJI was noted. Results Among the 197 patients with PJI and multiple joint prostheses in situ, 37 (19%) developed PJI in another joint; 11 had a synchronous PJI and 26 had a metachronous PJI. The average time between the first and the second infection in the metachronous cases was 848 days (range, 20 to 3,656 days). Females and patients with an initial PJI with methicillin-resistant Staphylococcus aureus (MRSA) were more likely to have a metachronous PJI, and patients with rheumatoid arthritis had an increased risk of a second (metachronous or synchronous) PJI. Three of 11 patients in the synchronous group and 19% (5) of the 26 in the metachronous group had bacteremia at the time of the initial PJI compared with 12% (19) of the 160 with a single PJI. The percentage of negative cultures increased from 10% for the initial PJIs to 38% for the metachronous PJIs. Conclusions Patients who have multiple prosthetic joints in place and present with PJI of a single joint are at risk of developing PJI in another joint. Female sex, rheumatoid arthritis, bacteremia at presentation, and infection with MRSA appear to be risk factors for PJI of another joint. Clinical evaluation of the other prosthetic joint(s) should be carried out in all patients and aspiration of those joint(s) should be considered for patients with any of the above risk factors. Level of evidence Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background Giant cell tumours (GCT) of the bone are benign and consist of aggressive local growth with rare metastatic disease. Its reported incidence in the immature skeleton is less than 10%, ranging from 1.8% to 10.6%. Few GCT series have been reported in the immature skeleton. In our ?country?, the overall incidence and impact of GCT in these patients is unknown. A series of 11 cases is presented, demonstrating their demographic characteristics, treatment, and follow-up.

Resumen El tumor de celulas gigantes de la vaina sinovial del tendon (TCGVS) es la segunda lesion mas frecuente de la mano y la muneca, y el 85% de estos tumores se originan en los dedos. Su localizacion mas frecuente es en los tres digitos radiales, especialmente en las articulaciones interfalangicas distales. La sobreexpresion de factor estimulante de colonias 1 (CSF1) se ha visto en la sinovitis vellonodular pigmentada (SVP) y en los TCGVS. Se reporta hasta el 50% de tasa de recurrencia. Con frecuencia, las recurrencias se tratan principalmente con resecciones quirurgicas amplias que pueden implicar la amputacion y el compromiso funcional de la mano. Presentamos el caso de una recurrencia de un TCGVS en un paciente con una lesion invasiva ubicada en el tendon del flexor profundo del pulgar que infiltraba toda la region tenar tratada mediante reseccion quirurgica e imatinib. El tumor de celulas gigantes puede responder a la terapia sistemica y esta opcion de tratamiento puede ser considerada en pacientes con margenes inadecuados o en zonas no accesibles. Adecuados resultados funcionales se pueden esperar con el tratamiento quirurgico y farmacologico combinado. Nivel de evidencia clinica Nivel IV.

Total knee arthroplasty (TKA) is a highly successful operation that improves patients' quality of life and functionality. Yet, up to 20% of TKA patients remain unsatisfied with their clinical result. Robotic TKA has gained increased attention and popularity as a means of improving patient satisfaction. The promise of robotic-assisted TKA is that it provides a surgeon with a tool that accurately executes bone cuts according to presurgical planning, as well as provides the surgeon with intraoperative feedback helpful for restoring knee kinematics and soft tissue balance. Several systems are now available, each with their own advantages and disadvantages. Evidence that the use of robotics will lead to improved implant survival, function, and patient-reported outcomes is slowly being accumulated, but this has not been clearly proven to date. Recent literature does show that the use of robotics during TKA is not associated with increased surgical time or complications. The goal of this review is to provide an objective assessment of the evidence surrounding robotic technology for TKA. © 2019 2019 by Thieme Medical Publishers, Inc. All rights reserved.

Background: It is strongly recommended that tissue and synovial fluid culture samples be obtained during reimplantation performed as part of a 2-stage exchange arthroplasty. The rate of positive cultures during reimplantation and the influence of positive cultures on subsequent outcomes, to our knowledge, are unknown. This study was designed to determine the rate of positive cultures during reimplantation and to investigate the association between positive cultures at reimplantation and subsequent outcomes. Methods: We retrospectively reviewed the data of 259 patients who met the Musculoskeletal Infection Society criteria for periprosthetic joint infection (PJI) and who underwent both stages of 2-stage exchange arthroplasty at our institution from 1999 to 2013. Among these patients were 267 PJIs (186 knees and 81 hips); 33 (12.4%) had ≥1 positive culture result at reimplantation. Treatment failure was assessed according to the Delphi-based consensus definition. Logistic regression analysis was performed to assess the predictors of positive culture and risk factors for failure of 2-stage exchange arthroplasty. Results: Of the 33 cases with PJI, 15 (45.5%) had a subsequent failure of the 2-stage exchange arthroplasty compared with 49 (20.9%) of the cases that were culture-negative at reimplantation. When controlling for other variables using multivariate analyses, the risk of treatment failure was higher (odds ratio = 2.53; 95% confidence interval [CI] = 1.13 to 5.64) and reinfection occurred earlier (hazard ratio = 2.00; 95% CI = 1.05 to 3.82) for the cases with a positive culture during reimplantation. The treatment failure rate did not differ (p = 0.73) between cases with ≥2 positive cultures (36.4%) and 1 positive culture (50%). Conclusions: Positive intraoperative culture at the time of reimplantation, regardless of the number of positive samples, was independently associated with >2 times the risk of subsequent treatment failure and earlier reinfection. Surgeons should be aware that a positive culture at the time of reimplantation independently increases the risk of subsequent failure. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Purpose The aim of this study was to compare the radioguided occult lesion localization (ROLL) technique with the wire-guided lesion localization (WGLL) technique to assess their efficacy and accuracy in the localization of nonpalpable breast lesions in patients at a unique reference medical center. These patients’ reports were negative for malignancy but included highly suspicious imaging findings. Methods A controlled clinical trial was designed to compare the WGLL and ROLL techniques in women presenting with breast lesions diagnosed by mammography or ultrasonography at the Instituto Nacional de Cancerologia in Bogota, Colombia, from March 2006 to June 2011. Results This study examined 129 patients; 64 (49.6%) patients were treated with ROLL, and 65 (51.4%) were treated with WGLL. The ROLL technique achieved better median lesion centricity (ROLL = 11.7 and WGLL = 15.4; P = .038). No significant differences were found regarding demographic variables, operative specimen characteristics, the need to extend margins, operative complications, the degree of difficulty, or patient or surgeon satisfaction. Conclusion The ROLL technique is as effective as WGLL for the localization of nonpalpable breast lesions. In our study, ROLL achieved better lesion centricity. Therefore, we propose that this technique could be used as a standard procedure in the detection of nonpalpable breast lesions at experienced centers.

Case A 29-year-old man was admitted with acute atraumatic left hip pain and inability to bear weight. Subsequent workup revealed an intracapsular pathologic fracture of the femoral neck secondary to a high-grade spindle cell sarcoma. A unique method of extra-articular resection and reconstruction using a 3-dimensional (3D)-printed custom cutting jig and a custom acetabular component was pursued. Wide margins were achieved without violating the joint capsule but preserving pelvic integrity, allowing a return to an active lifestyle. Conclusion Three-dimensional-printed custom resection guides and implants can help achieve adequate resection margins while preserving pelvic integrity and function.

Whether prolonged operative time is an independent risk factor for subsequent surgical site infection (SSI) and periprosthetic joint infection (PJI) following total joint arthroplasty (TJA) remains a clinically significant and underexplored issue. The aim of this study is to investigate the association between operative time and the risk of subsequent SSI and PJI in patients undergoing primary TJA.We retrospectively reviewed 17,342 primary unilateral total knee arthroplasty and total hip arthroplasty performed at a single institution between 2005 and 2016, with a minimum follow-up of 1 year. A multivariate logistic regression model was conducted to identify the association between operative time and the development of SSI within 90 days and PJI within 1 year.Overall, the incidence of 90-day SSI and 1-year PJI was 1.2% and 0.8%, respectively. Patients with an operative time of90 minutes had a significantly higher incidence of SSI and PJI (2.1% and 1.4%, respectively) compared to cases lasting between 60 and 90 minutes (1.1% and 0.7%), and those lasting ≤60 minutes (0.9% and 0.7%, P.01). In the multivariate model, the risk for infection increased by an odds ratio of 1.346 (95% confidential interval 1.114-1.627) for 90-day SSI and 1.253 (95% confidential interval 1.060-1.481) for 1-year PJI for each 20-minute increase in operative time.In patients undergoing primary TJA, each 20-minute increase in operative time was associated with nearly a 25% increased risk of subsequent PJI. We advocate that surgeons pay close attention to this underappreciated risk factor while maintaining safe operative practices, which minimize unnecessary steps and wasted time in the operating room.

Background: Underweight (UW) patients undergoing total hip arthroplasty have exhibited higher complication rates, including infection and transfusion. No study to our knowledge has evaluated UW total knee arthroplasty (TKA) patients. We, therefore, conducted a study to investigate if these patients are at increased risk for complications, including infection and transfusion. Methods: A case-control study was conducted using a prospectively collected institutional database. Twenty-seven TKA patients were identified as UW (body mass index [BMI] < 18.5 kg/m2) from 2000-2012 and were matched for age, gender, date of surgery, age-adjusted Charlson comorbidity index, rheumatoid arthritis, and diabetes. These patients were compared to 81 normal weight patients (BMI 18.5-24 kg/m2). Demographic variables were compared, along with wound complications, surgical site infection (SSI), blistering, deep vein thrombosis, pulmonary embolism, transfusion, revision, flexion contracture, hematoma formation, and patellar clunk. Results: The average BMI was 17.1 kg/m2 (range 12.8-18.4) for UW and 23.0 kg/m2 (range 19.0-25.0) for normal weight patients (P < .001). UW TKA patients were more likely to develop SSIs (3/27, 11.1% vs 0/81, 0.0%, P = .01) and were more likely to require transfusions (odds ratio = 3.4, confidence interval 1.3-9.1; P = .02). Conclusions: Our study demonstrates that UW TKA patients have a higher likelihood of developing SSI and requiring blood transfusions. The specific reasons are unclear, but we conjecture that it may be related to decreased wound healing capabilities and low preoperative hemoglobin. Investigation of local tissue coverage and hematologic status may be beneficial in this patient population to prevent SSI. Based on the results of this study, a prospective evaluation of these factors should be undertaken.

Irrigation and debridement with prosthetic retention (ID) is an oft-utilized treatment option for PJI, despite its known limited success. While it is known that nearly half of all patients treated with ID have recurrent infection, the organism persistence between infection events remains unreported. In addition, identifying those cases in which ID routinely failed to eradicate the infection (not simply prevent recurrent infection) may allow improved patient selection for this less morbid procedure-a difficult task to date.Using an institutional database, 146 patients (153 joints) undergoing ID between April 2000 and July 2013 were identified. There were 60 hips (40%). The overall success rate of ID in this group was 52% (80/153). The failure group was limited to those patients with growth on culture at both initial failure and recurrent failure (46 cases). Analyses were performed to identify potential predictors of failed ID and organism persistence in those cases.In the study group, 83.7% (36/43) of cases failed with the same organism. Knees with failed ID had an organism persistence of 92.3% (24/26) compared with 70.5% (12/17; P = .09) for the hip. Patients initially infected with Staphylococcus aureus (specifically methicillin-resistant [13/13]) had a higher risk of persistent PJI (96%; 24/25) compared to other organisms (66.7%; 12/18; P = .01).ID had a success rate of approximately 50% and typically failed due to organism persistence rather than a new infection. Given that persistent infection was most common in knees and S aureus, ID should have a limited role in treating PJI, especially in these cases.

Objective: To describe the initial experience of isolated limb perfusion at the National Cancer Institute. Methods: Pathology and response to intervention was documented in the cases of 13 patients taken from years 2007 to 2008. Results: Limb salvage was 76%; local complications, 16%. Five patients (41.7%) had partial response; two more (16.7%), disease progression. No patients had complete clinical response. Conclusions: Isolated limb perfusion provides a good alternative for treating melanoma and advanced sarcomas in limbs; possibly sparing them from amputation. Due to the number of patients included in this article, and to the need to establish more solid conclusions, it is necessary to carry out closer patient follow-up by setting up a prospective research project whose results will establish type of response, disease free interval, overall survival and a quality-of-life scale for patients who receive this kind of treatment.

Background: Two-stage exchange arthroplasty remains the preferred method to treat periprosthetic joint infection. The aim of this study was to investigate the clinical course of periprosthetic joint infection following resection arthroplasty and insertion of a spacer. Methods: Our institutional database was used to identify 504 cases of periprosthetic joint infection (326 knees and 178 hips) treated with resection arthroplasty and spacer insertion as part of a two-stage exchange arthroplasty. A review of the patient charts was performed to extract information relevant to the objectives of this study that included the details of the clinical course following resection arthroplasty. Results: The mean follow-up duration after initial spacer implantation was 56.2 months. Reimplantation occurred in the joints of 417 (82.7%) of 504 cases. Of these 417 cases, 329 (78.9%) had a minimum one-year follow-up, and 81.4% of these had successful treatment. The mean duration from resection arthroplasty to reimplantation was 4.2 months (range, 0.7 to 131.7 months). Sixty (11.9%) of the 504 joints required interim spacer exchange(s). Of the eighty-seven cases that did not undergo reimplantation, six (6.9%) required amputation, five (5.7%) underwent a Girdlestone procedure, four (4.6%) underwent arthrodesis, and seventy-two (82.8%) underwent spacer retention. Thirty-six patients died in the interstage period. Conclusions: The commonly held belief that two-stage exchange arthroplasty carries a high success rate for the eradication of periprosthetic joint infection may need to be reexamined. A considerable number of patients undergoing the first stage of a two-stage procedure do not undergo a subsequent reimplantation for a variety of reasons or require an additional spacer exchange in the interim. Reports on the success of two-stage exchange should account for the mortality of these patients and for patients who never undergo reimplantation. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

After the successful treatment of periprosthetic joint infection (PJI), patients may present with degenerative joint disease in another joint with symptoms severe enough to warrant arthroplasty. However, it is not known whether patients with a history of treated PJI at one site will have an increased risk of PJI in the second arthroplasty site.The primary objective of this study is to determine if there is a difference in the risk of developing a PJI after a second total hip arthroplasty (THA) or total knee arthroplasty (TKA) in patients who have had a previous PJI at another anatomic site compared with patients who have had no history of PJI. The secondary objective is to determine other potential risk factors that may predict PJI at the site of the second arthroplasty.A retrospective matched cohort study was performed to identify all patients at four academic institutions successfully treated for PJI who subsequently underwent a second primary THA or TKA (n = 90), constituting our study group. Patients were matched (one-to-one) to control subjects who had no history of PJI after their first arthroplasty (n = 90); they were matched based on age, sex, diabetic status, BMI, American Society of Anesthesiologists, institution, joint of interest, and year of surgery (± 2 years). We compared the case and control groups to determine whether a prior infection increased the relative risk of a subsequent PJI at another anatomic site. To identify other potential risk factors for subsequent PJI, a subgroup univariate analysis of our study group (n = 90) was performed. To identify other potential risk factors for subsequent PJI, a subgroup univariate analysis of our study group (n = 90) was performed.Patients with a history of PJI had a greater risk of developing PJI in a subsequent THA or TKA (10 of 90 versus zero of 90 in the control group; relative risk, 21.00; 95% confidence interval [CI], 1.25-353.08; p = 0.035). Excluding PJI, we identified no other factors associated with a second joint infection. In patients with a history of PJI, a second PJI occurred more frequently in female patients (female: nine of 10 [90%] versus female: 40 of 80 [50%]; odds ratio [OR], 8.83; 95% CI, 1.13-403.33; p = 0.02) and in those whose initial infection was a staphylococcal species (subsequent PJI seven of 10 [70%] versus no subsequent PJI 28 of 80 [35%]; OR, 4.26; 95% CI, 0.89-27.50; p = 0.04).A history of PJI predisposes patients to subsequent PJI in primary THA or THA. Patients and surgeons must be aware of the higher risk of this devastating complication before proceeding with a second arthroplasty.Level III, prognostic study.

Periprosthetic joint infection (PJI) continues to challenge the orthopedic community. As the need for total knee arthroplasty (TKA) continues to increase and is more frequently being performed in younger patients, the absolute number of infected patients is expected to increase. Currently, infection after TKA is the leading reason for early readmission and the main cause of revision arthroplasty within the first two years after surgery. There is no perfect treatment option; rather, there are a variety of alternatives that carry their own set of benefits and flaws. Moreover, clinical results of these treatment options are always expected to be lower than the outcomes achieved after a primary TKA. The accuracy in selecting the appropriated treatment option for each patient is key for achieving positive results. Each case should be considered with all available evidence to successfully eradicate the infection and prevent reinfection. This chapter describes the different treatment options, their indications, steps, and the available up-to-date results for treating PJI after TKA.

Periprosthetic joint infection (PJI) is the most feared and challenging complication after total knee arthroplasty (TKA) due to the difficulty in diagnosis and treatment. The patient is exposed to multiple procedures, increasing the risk of complications, and finally compromising functional outcome. Currently, there is no gold standard test for PJI, and the final diagnosis is accomplished by combining clinical suspicion with inflammatory marker results. Two-stage exchange arthroplasty remains the preferred method of treatment for chronic PJI in TKA, with a high rate of success reported in literature. However, failures and complications in two-stage exchange can occur. There are no clarified guidelines to treat complications or treatment failures. Thus, each case should be individualized to offer options that match the patient’s expectations with what is achievable. The case report in this chapter represents the worst case scenario after a TKA, and is a reminder that the gold standard is far from perfect, while it outlines multiple instances a surgeon could encounter.

Stiffness after total knee arthroplasty (TKA) adversely affects outcome and impacts patient function. Various risk factors for stiffness after TKA have been identified, including reduced preoperative knee range of motion, history of prior knee surgery, etiology of arthritis, incorrect positioning or oversizing of components, and incorrect gap balancing. Mechanical and associated causes, such as infection, arthrofibrosis, complex regional pain syndrome, and heterotopic ossification, secondary gain issues have also been identified. Management of stiffness following TKA can be challenging. The condition needs to be assessed and treated in a staged manner. A nonsurgical approach is the first step. Manipulation under anesthesia may be considered within the first 3 months after the index TKA, if physical therapy fails to improve the range of motion. Beyond this point, consideration should be given to surgical intervention such as lysis of adhesions, either arthroscopically or by open arthrotomy. If the cause of stiffness is deemed to be surgical error, such as component malpositioning, revision arthroplasty is indicated. The purpose of this article is to evaluate the various aspects of management of stiffness after TKA.

Surgical equipment can become contaminated during surgery. It is unknown if electrocautery tips can become contaminated in clean orthopedic procedures despite the produced heat. Therefore, we conducted a prospective study to address this concern. The tips from 25 primary and 25 aseptic revision THAs were collected and an additional 5 sterile tips served as negative controls. Aerobic and anaerobic cultures were incubated for a minimum of 3 days. There were 3 positive cultures (6%); one in primary THA (4%) with Lactobacillus and Enterococcus faecalis; two among revisions (8%), one with E. faecalis and another one with alpha hemolytic streptococci and coagulase negative Staphylococcus. The mean exposure time of the contaminated tips was 132.3 minutes. Patients were followed for 90 days postoperatively and none of them developed surgical site infection. This is the first study to demonstrate that electrosurgical devices can become contaminated during THA in laminar flow equipped operating rooms.

El estudio se realizó en el distrito de Tamburco (Abancay, Apurímac, Perú), con el objetivo de comparar la interpretación de los resultados de la prueba «California Mastitis Test» (CMT) en el diagnóstico de la mastitis subclínica en bovinos. Se trabajó con 209 vacas de una población de 459 en ordeño manual, pertenecientes a 95 criadores, donde se evaluaron 828 cuartos mamarios funcionales y se estimaron los principales criterios de interpretación de la CMT. La prevalencia de mastitis subclínica fue de 72.3 y 65.6% en las vacas y de 48.7 y 42.3% en el total de cuartos mamarios, considerando y sin considerar trazas como positivos, respectivamente, y sin diferencia significativa. La prevalencia de mastitis subclínica en los cuartos mamarios individuales varió entre 48.3 y 49.3% y de 40.0 y 45.5%, según el cuarto, considerando y sin considerar trazas, respectivamente (p

A single subcutaneous injection of amphenone to pyloric ligated rats produced a significant decrease in gastric secretory volume, free acid and potassium content, with an increase in pH, gastric juice sodium and pepsin concentration. Cortisone, corticosterone, DCA or ACTH administered with amphenone did not alter the amphenone effect. Aldosterone alone produced a reduction in gastric juice sodium. When amphenone was injected with aldosterone, the amphenone effects, including an increased sodium, were again observed. When amphenone was administered with histamine, the amphenone effects relating to pH and free acid concentration were not observed. Adrenalectomy produced a decrease in gastric secretory volume, acidity and pepsin secretion, and an increase in sodium and pH. In previously adrenalectomized rats the amphenone inhibitory effects on gastric secretion were absent. An increase in adrenal gland weight was observed 4 hours after amphenone administration, but was not seen when cortisone, corticosterone, DCA, aldosterone or histamine were administered with amphenone. ACTH alone or with amphenone produced an increase in adrenal weight. Amphenone caused a considerable increase in thymus weight, which could be prevented by the simultaneous injection of corticosterone, aldosterone or histamine, but not by DCA or adrenalectomy. ACTH or cortisone alone or in combination with amphenone decreased thymus weight.