Usefulness of histology for predicting infection at the time of hip and knee revision in patients with rheumatoid arthritis.

INTRODUCTION: It remains unclear whether rheumatoid arthritis might be a cause of false positive of the histology for the diagnosis of prosthetic joint infection. Our aim was to evaluate the usefulness of the histology for the diagnosis of infection during hip and knee prosthesis revision in patients with rheumatoid arthritis. MATERIALS AND METHODS: All patients with the diagnosis of rheumatoid arthritis (RA) undergoing hip or knee revision surgery (total or partial) were retrospectively reviewed. Positive histology was considered when ≥ 5 neutrophils per high-power field (400×) were found in at least five separate microscopic fields. Patients who presented ≥ 2 positive cultures for the same microorganism or the presence of fistula were considered as "true positives". RESULTS: Thirty-two hip (n = 12) and knee (n = 20) revision procedures were performed. Sensitivity, specificity, positive and negative predictive value of the histology were 50%, 78.6%, 25% and 91.7%, respectively. Six out of the eight patients presenting with positive histology had negative cultures (75.0% of false positives). CONCLUSIONS: Our results suggest that, in the context of RA, negative histological results have a very high negative predictive value. RA poses false positive histology results for the diagnosis of infection during hip and knee revision when conventional cultures are used for diagnosis of infection.

Assessment of neural networks and time series analysis to forecast airborne Parietaria pollen presence in the Atlantic coastal regions.

Pollen forecasting models are a useful tool with which to predict episodes of type I allergenic risk and other environmental or biological processes. Parietaria is a wind-pollinated perennial herb that is responsible for many cases of severe pollinosis due to its high pollen production, the long persistence of the pollen grains in the atmosphere and the abundant presence of allergens in their cytoplasm and walls. The aim of this paper is to develop artificial neural networks (ANNs) to predict airborne Parietaria pollen concentrations in the northwestern part of Spain using a 19-year data set (1999-2017). The results show a significant increase in the length of time Parietaria pollen is in the air, as well as significant increases in the annual Parietaria pollen integral and mean daily maximum pollen value in the year. The Neural models show the ability to forecast airborne Parietaria pollen concentrations 1, 2, and 3 days ahead. A developed model with five input variables used to predict concentrations of airborne Parietaria pollen 1 day ahead shows determination coefficients between 0.618 and 0.652.

Successful prophylactic measures for the eradication of Staphylococcus aureus infections in elective hip primary and revision arthroplasty.

INTRODUCTION: Staphylococcus aureus stands as the predominant etiological agent in postoperative acute prosthetic joint infections (PJI), contributing to 35-50% of reported cases. This study aimed to evaluate the efficacy of dual prophylaxis incorporating cefuroxime and teicoplanin, in combination with nasal decolonization utilizing 70% alcohol, and oral and body lavage with chlorhexidine. MATERIAL AND METHODS: We conducted a retrospective review of electronic health records regarding primary and revision arthroplasties conducted at our institution from 2020 to 2021. Relevant variables linked to prosthetic joint infections (PJI) were documented until the latest follow-up. RESULTS: A total of 539 operations (447 primary arthroplasties and 92 revision arthroplasties) were performed on 519 patients. There were 11 cases of postoperative acute PJI, resulting in infection rates of 1.6% for primary arthroplasties and 4.3% for revision surgeries. Infections were more prevalent in male patients, individuals with an ASA classification>II, and those undergoing longer operations (>90min). S. aureus was not isolated in any of the cases. CONCLUSION: The prophylactic measures implemented in our institution have exhibited a high efficacy in preventing postoperative acute PJI caused by S. aureus.

Assessment of cerebral blood flow velocities, brain midline shift and optic nerve sheath diameter by ultrasound in patients undergoing elective craniotomy: A prospective observational feasibility study.

BACKGROUND: Brain ultrasound allows measuring the cerebral flow velocity, brain midline shift and optic nerve sheath diameter. Literature is scarce in determining the feasibility to perioperatively perform these measurements altogether and the cerebrovascular behavior in patients scheduled for elective craniotomy. METHODS: We assessed bilateral cerebral flow velocities, composite index, brain midline shift and optic nerve sheath diameter by cerebral ultrasound in patients scheduled for elective craniotomy before anesthetic induction, at extubation, and at 6 and 24 h after. The aim was to assess the feasibility of brain ultrasound in patients for elective craniotomy and to describe the changes in cerebral flow velocities, brain midline shift and optic nerve sheath diameter from baseline values at different times in the postoperative period. RESULTS: Sixteen patients were included, of these two were excluded from analysis due to an inadequate sonographic window. There were no changes throughout the study regarding cerebral flow velocity, brain midline shift nor optic nerve sheath diameter assessments. All parameters were maintained in the physiological range without significant variations during the procedure. No perioperative complications were detected. CONCLUSIONS: The results of our study show the feasibility to perform a perioperative assessment of cerebral flow velocity, brain midline shift or optic nerve sheath diameter jointly and successfully to obtain additional information of baseline cerebral hemodynamics in patients scheduled for elective craniotomy and their postoperative changes during the first 24 h. Future studies with lager samples are needed to address the efficacy of cerebral ultrasound as a monitoring tool.

Outdoor and synthetic performance data for PV devices concerning the weather conditions and capacitor values of I-V tracer.

This article presents the outdoor and synthetic performance data concerning the main electrical parameters estimated from the I-V curve for three photovoltaic technologies (HIT, m-Si and CIGS) and the weather conditions (irradiance, ambient and panel temperature). Synthetic data were generated by simulating in OpenModelica software the impact of weather conditions on device performance, considering an irradiance range between 50 and 1300 W/m2. The outdoor data corresponds to the performance of the evaluated PV modules in outdoor tests in Medellin-Colombia for ten months using capacitive I-V tracers. In both cases, different capacitor values were considered to evaluate the effect on the I-V curve behavior of devices.

Percutaneous cementoplasty of periprosthetic aseptic hip loosening.

Progressive population aging and improved healthcare have led to a significant increase in patients with hip arthroplasty (HA). In this patient group, the proportion of those who require a new arthroplasty (prosthetic replacement or secondary revision of the hip), has also increased. For this subgroup of patients in whom surgical prosthetic replacement should be considered but is contraindicated, a new technique has been developed since 2010: percutaneous injection of periprosthetic cement under fluoroscopic or CT control ("femoroplasty; FMP") as an alternative and less invasive treatment compared to surgery to stabilize the HA without replacing it, with excellent results on patients' quality of life. In this brief communication, we describe our positive experience regarding FMP, which we have performed for the first time in Spain on four patients (age range between 74-83 years, 2 female and 2 male patients, 3 right HA and 1 left HA), without post-complications. We highlight both the relative simplicity of this technique, which can be incorporated into radiological intervention even in regional hospitals, and the significant clinical improvement observed in all patients. In conclusion, we hope that our experience can contribute to the increased adoption of this innovative technique within the scientific community.

Visual impairment induced by prosthetic cobaltism.

The case of a 68-year-old patient with visual loss secondary to prosthetic cobaltism is reported. The degeneration of the metallic hip prosthesis can produce a systemic absorption of cobalt with cardiac, neurological, endocrine, auditory, and visual manifestations. The diagnostic suspicion is confirmed by serum cobalt measurements. Treatment with early surgery and chelating agents can lead to improvement of the visual, and the other disorders.

The anterior limited approach of the elbow for the treatment of capitellum and trochlea fractures: Surgical technique and clinical experience in eight cases.

When a coronal fracture affects the capitellum and the trochlea, the Kocher lateral approach may be inadequate for the correct visualisation, reduction and fixation of the fracture. In such cases an associated medial elbow approach may be required, or a posterior transolecranon approach may be preferred. The anterior limited approach to the elbow (ALAE) could be a valid option when treating these types of fracture, as it does not involve the detachment of any muscle group or ligament, thereby facilitating the recovery process. We can also treat associated injuries such as fractures of the radial head or coronoid process with this approach. We describe the surgical technique and the functional outcome of eight patients with a mean of 66 years of age (range, 53-76) who where treated with open reduction and internal fixation for capitellar and trochlear fractures through the ALAE. Patient outcomes were assessed with physical and radiological evaluation, range-of-motion measurements with a follow-up from 24 to 60 months. Two different quality of life questionnaires were carried out: the EuroQol Five Dimensions Questionnaire (EQ-5D) and the patient-answered questionnnaire of the Liverpool Elbow Score patient (PAQ-LES). Four fractures involved the capitellum, one involved the capitellum with the lateral ridge of the trochlea, and three involved the capitellum and trochlea as separate fragments. The patients presented a favorable clinical evolution at a median of 33 months (range, 24-60), with an average of motion of 10-138°. Four patients presented a fracture of the head of the radius (Mason type 2) and 3 fractures of the coronoid (Bryan-Morrey Type 1) associated. All the patients presented radiological consolidation without signs of osteonecrosis, being the average EQ-5D 0.857 (range, 0.36-1.0) and the PAQ-LES of 35 (range 17 to 36). Patients with isolated capitellar fractures had better results than those with trochlear involvement. The presence of associated fractures does not seem to worsen the results. We believe that the ALAE is a technical option to consider for the open surgical treatment of a capitellar fracture with or without involvement of the trochlea. LEVEL OF EVIDENCEIS: Therapeutic Level III.

Hip prostheses in young adults. Surface prostheses and short-stem prostheses. / Las prótesis de cadera en el adulto joven. Prótesis de superficie y prótesis de vástago corto.

The poor results obtained in young patients when using a conventional prosthesis led to the resurgence of hip resurfacing to find less invasive implants for the bone. Young patients present a demand for additional activity, which makes them a serious challenge for the survival of implants. In addition, new information technologies contribute decisively to the preference for non-cemented prostheses. Maintaining quality of life, preserving the bone and soft tissues, as well as achieving a very stable implant, are the goals of every hip orthopaedic surgeon for these patients. The results in research point to the use of smaller prostheses, which use the metaphyseal zone more and less the diaphyseal zone, and hence the large number of the abovementioned short stem prostheses. Both models are principally indicated in the young adult. Their revision should be a more simple operation, but this is only true for hip resurfacing, not for short stems.

The limited anterior approach of the elbow for open reduction and internal fixation of capitellum fractures. Surgical technique and clinical experience in 2 cases with more than 2 years follow-up. / Abordaje anterior limitado del codo para la reducción abierta y fijación interna de las fracturas del capitellum. Técnica quirúrgica y experiencia clínica en 2casos con más de 2 años de seguimiento.

OBJECTIVE: Fractures involving the capitellum can be treated surgically by excision of the fragment, or by reduction and internal fixation with screws, with or without heads. The lateral Kocher approach is the most common approach for open reduction. We believe that the limited anterior approach of the elbow, could be a valid technique for treating these fractures, as it does not involve the detachment of any muscle group or ligament, facilitating the recovery process. MATERIAL AND METHOD: A description is presented of the surgical technique, as well as of 2cases with a Bryan-Morrey type 1 fracture (Dubberley type 1A). Two different final quality of life evaluation questionnaires were completed by telephone: the EuroQol Five Dimensions Questionnaire (EQ-5D), and the patient part of the Liverpool Elbow Score (PAQ-LES) questionnaire. RESULTS: The 2patients showed favourable clinical progress at 36 and 24 months, respectively, with an extension/flexion movement arc of -5°/145° and -10°/145°, as well as a pronosupination of 85°/80° and 90°/90°. The 2patients showed radiological consolidation with no signs of osteonecrosis. The EQ-5D score was 0.857 and 0.910 (range: 0.36-1), and a PAQ-SLE of 35 and 35 (range: 17-36), respectively. CONCLUSIONS: We believe that the limited anterior approach of the elbow is a technical option to consider for the open surgical treatment of a capitellum fracture, although further studies are needed to demonstrate its superiority and clinical safety compared to the classical lateral Kocher approach.

Metabolomic Analysis Reveals Vitamin D-induced Decrease in Polyol Pathway and Subtle Modulation of Glycolysis in HEK293T Cells.

We combined 1H NMR metabolomics with functional and molecular biochemical assays to describe the metabolic changes elicited by vitamin D in HEK293T, an embryonic proliferative cell line adapted to high-glucose concentrations. Activation of the polyol pathway, was the most important consequence of cell exposure to high glucose concentration, resembling cells exposed to hyperglycemia. Vitamin D induced alterations in HEK293T cells metabolism, including a decrease in sorbitol, glycine, glutamate, guanine. Vitamin D modulated glycolysis by increasing phosphoglycerate mutase and decreasing enolase activities, changing carbon fate without changing glucose consumption, lactate export and Krebs cycle. The decrease in sorbitol intracellular concentration seems to be related to vitamin D regulated redox homeostasis and protection against oxidative stress, and helped maintaining the high proliferative phenotype, supported by the decrease in glycine and guanine and orotate concentration and increase in choline and phosphocholine concentration. The decrease in orotate and guanine indicated an increased biosynthesis of purine and pyrimidines. Vitamin D elicited metabolic alteration without changing cellular proliferation and mitochondrial respiration, but reclaiming reductive power. Our study may contribute to the understanding of the metabolic mechanism of vitamin D upon exposure to hyperglycemia, suggesting a role of protection against oxidative stress.

Allograft reconstruction of the distal humerus after resection of a breast solitary metastasis: eleven years follow-up.

Resection is a rare indication for the treatment of solitary skeletal metastasis (SSM), and provides an opportunity to cure the oncologic patient. Reconstruction after resection can imply a difficult problem depending on the size and the location of the metastasis. In the reported case, an en-bloc resection of a SSM of a breast cancer located in the distal humerus was performed in 1990. Reconstruction of the osteoarticular defect has been achieved with a massive allograft. At eleven years follow-up the patient remains free of illness and shows a good functional result. With the result obtained in the reported case, we suggest that osteoarticular allograft can be of considerable value for reconstruction after excision of SSM in the distal humerus, and that cure can be achieved with the radical resection of a SSM of breast cancer.

Long-term results of hemipelvic allograft: Report of four cases.

Reconstruction after the excision of pelvic tumors involving the pelvic ring implies difficult problems. Restoration of the function is difficult and an allograft can be one of the possible solutions. Pelvic allograft is recommended by many authors to reconstruct the pelvic ring following extensive resections of bone tumors. Between 1988 and 1989, we performed hemipelvic resection and allograft reconstruction in 4 patients with pelvic sarcomas. The mean age was 42.3 years (range 38-48), consists of 3 male and 1 female. One case developed an infection and one case showed recurrence, both responding to surgical treatment. Outcome in those cases in which surgery was curative to the primary tumor was satisfactory at 10 years follow-up, with a mean total Enneking score of 25.3 (range 24-27) and a good functional result in Merlé D'Aubigne functional score. Despite the limited number of cases presented, our results added to the reported results in the literature led us to consider that allografts are valuable in pelvic reconstructions after en-bloc resections for bone tumors.

Arthrodesis of the talonavicular-cuneiform joints in Müller-Weiss disease.

Several surgical treatments have been proposed to correct the deformity associated with MWD and alleviate the pain; however, no technique can be named the gold standard. TNC arthrodesis is a safe and effective technique for the treatment of the MWD and can be performed with a dorsal or medial approach;we recommend the dorsal approach. We believe that autologous bone graft provides sufficient stability and internal fixation is not needed. Treatment of MWD is not well-documented in literature; more studies are needed to determine the optimum surgical treatment for this rare disease.

Presumptive infection of a total hip prosthesis by Mycobacterium tuberculosis: a case report.

Infection of a total hip prosthesis by Mycobacterium tuberculosis (MT) is an uncommon complication. We report a patient with septic loosening of a total hip prosthesis with a presumptive diagnosis of MT infection. His previous history was negative to any form of tuberculosis, and there was no evidence of a primary focus on the radiological study of the chest. He was diagnosed initially as presenting aseptic loosening and revision surgery was performed. Six months after surgery, septic loosening was diagnosed. The prosthesis was then removed. The histological study showed caseum granulomas and acid-fast bacilli, and routine cultures of the synovial fluid were negative. Since only a positive Löwenstein culture would have confirmed the diagnosis with certainty, a presumptive diagnosis of MR infection was made based on the findings in the histological study. Tuberculostatic treatment was administered for 9 months. At six years follow-up no signs of infection are present, neither by clinical or radiological criteria.

Rupture of Extensively Porous Coated Stems. - A Case Series of 2 Patients.

INTRODUCTION: Mechanical failure of femoral stems of revision hip arthroplasty has been rarely reported. In the current study, the cause of two stem fractures, which occurred in vivo, was analysed with use of clinical and radiological data, and the functional result after revision is presented. CASE REPORT: Two patients, A 70-year-old male and a 73-year-old female, both of Mediterranean ethnic, and both patients underwent a revision total hip replacement to an uncemmented extensively porous coated stem. Both stems suffered an implant fatigue in vivo at three years and at two years follow-up respectively. CONCLUSION: Revision total hip arthroplasty is a procedure that will be performed more often the following years due to aging of population. Any orthopaedic surgeon performing hip surgery should be aware of the risk factors that can lead to total hip arthroplasty failure. In the analysed cases we can learn that the main factors related to this failure included the use of a small size stem (inferior to 14mm), an inadequate proximal osseous support because of trochanteric osteotomy, and a reduced preoperative bone stock. Although the use of cables has not been stated as a predisposing factor, we consider that they could also play a role in the development of this rare complication.

[Analysis of the failures of a cemented constrained liner model in patients with a high dislocation risk]. / Análisis de los fracasos de un modelo de cotilo constreñido cementado en pacientes de alto riesgo de luxación.

OBJECTIVE: To evaluate the short-term results of an ultra high molecular weight polyethylene retentive cup in patients at high risk of dislocation, either primary or revision surgery. MATERIAL AND METHOD: Retrospective review of 38 cases in order to determine the rate of survival and failure analysis of a constrained cemented cup, with a mean follow-up of 27 months. We studied demographic data, complications, especially re-dislocations of the prosthesis and, also the likely causes of system failure analyzed. RESULTS: In 21.05% (8 cases) were primary surgery and 78.95% were revision surgery (30 cases). The overall survival rate by Kaplan-Meier method was 70.7 months. During follow-up 3 patients died due to causes unrelated to surgery and 2 infections occurred. 12 hips had at least two previous surgeries done. It wasn't any case of aseptic loosening. Four patients presented dislocation, all with a 22 mm head (P=.008). Our statistical analysis didn't found relationship between the abduction cup angle and implant failure (P=.22). CONCLUSIONS: The ultra high molecular weight polyethylene retentive cup evaluated in this series has provided satisfactory short-term results in hip arthroplasty patients at high risk of dislocation.

Nonoperative treatment of distal biceps brachii musculotendinous partial rupture: a report of two cases.

Musculotendinous ruptures of the distal biceps brachii are extremely rare injuries whose clinical presentation is similar to distal biceps avulsion. We describe two cases of patients who suffered a distal biceps brachii musculotendinous partial rupture. The first patient was playing soccer as goalkeeper and experienced sudden pain while throwing the ball overhead with his left arm. The second patient experienced sudden pain while weightlifting with his right arm. The mechanism of injury was the same in the two cases, as both involved glenohumeral elevation with elbow extension and forearm supination. Neither of these two patients underwent surgical repair or rehabilitation, and both had perfect scores of 100 on the Mayo Clinic Performance Index for the Elbow at one-year followup.

Treatment of AO Type C Fractures of the Distal Part of the Humerus through the Bryan-Morrey Triceps-Sparing Approach.

Several alternative approaches have been described to avoid the complications related to the olecranon osteotomy used to treat distal articular humerus fractures. The published experience with the triceps-sparing approach is scant. In this prospective study, a total of 12 patients with an articular humeral fracture were treated using this approach. At a mean followup of 1,7 years, the average range of motion was 112.8° (range from 85° to 135°); the elbow flexion averaged 125.5° (range from 112° to 135°) and the deficit of elbow extension 14.6° (range from 0° to 30°). All the elbows were stable. The Mayo Elbow Performance Score (MEPS) averaged 93.3 (range from 80 to 100). In the present series no failure of the triceps reattachment to the olecranon was found, and all the patients recalled returning to their previous daily life activities without impairment with a satisfactory MEPS. As a conclusion, the triceps-sparing approach can be considered for treating distal articular humerus fractures. We consider that three clinical settings can be more favorable to use this approach: those cases in which a total elbow prosthesis might be needed, cases of ipsilateral diaphyseal fracture, or presence of previous hardware in the olecranon.