Prediction of 3-Dimensional Coverage Surface Area of the Femoral Head in Hip Dysplasia Through Conventional Computed Tomography.

Background: Assessment of 3-dimensional (3D) femoral head coverage is critical in evaluating, preoperative planning, and treating hip dysplasia. Purpose: To (1) propose a mathematical model to establish 3D femoral head coverage using conventional computed tomography (CT), (2) determine the correlation of 2D parameters with 3D coverage, and (3) characterize the patterns of dysplasia based on 3D morphology. Study Design: Cross-sectional study; Level of evidence, 3. Methods: We identified 30 patients (n = hips) with symptomatic dysplasia and 30 patients (n = hips) without dysplasia. Patients with dysplastic hips were matched with regard to sex, age, and body mass index to those with nondysplastic hips. Preoperative CTs were analyzed using 3D software, and 3D femoral head surface area coverage (FHSAC; in %) was assessed in 4 quadrant zones: anteromedial, anterolateral, posteromedial, and posterolateral. To assess lateral coverage of the femoral head, we introduced the anterolateral femoral head coverage angle (ALFC) and the posterolateral femoral head coverage angle (PLFC). Results: Reduced femoral head coverage was more pronounced in dysplastic versus nondysplastic hips in the anterolateral quadrant (18% vs 40.7%, respectively) and posterolateral quadrant (35.8% vs 56.9%, respectively) (P < .0001 for both). Dysplastic hips had smaller ALFC and PLFC (18.4° vs 38.7°; P < .0001; 47.2° vs 72.3°; P = .0002). Anterolateral and posterolateral FHSAC were strongly correlated with the ALFC (r = 0.88; P < .0001) and the PLFC (r = 0.82; P < .0001) along with the lateral center-edge angle (anterolateral, r = 0.75; P < .0001; posterolateral, r = 0.73; P < .0001). Prediction models established for FHSAC had strong agreement with explanatory CT variables (anterolateral: r = 0.91; P < .0001; posterolateral: r = 0.90; P < .0001). The cutoff values for anterolateral and posterolateral FHSAC were 25% and 41%, respectively. In dysplastic hips, global deficiency was most common (15/30 hips), 9 hips showed an anterolateral deficiency, and 4 hips had a posterolateral deficiency pattern. Conclusion: The ALFC and The PLFC were strongly correlated with 3D lateral FHSAC and were able to predict 3D coverage accurately.

Medium-term outcomes of conventional versus short uncemented femoral stems for primary total hip arthroplasty in patients younger than 55 years.

BACKGROUND: Short stems are designed with a bone preservation philosophy in mind. This study aims to compare the outcomes/complications and survival of a collarless fully hydroxyapatite (HA)-coated conventional tapered stem and a HA-coated partial neck-retaining uncemented short stem in patients ⩽55 years old at medium-term follow-up. METHODS: We retrospectively studied 247 uncemented THAs operated between 2010 and 2014, comparing 146 patients treated with the fully HA-coated collarless stem (Group A) with 101 patients treated with a partial neck preserving, HA-coated short stem (Group B). 87 and 62 males were in groups A and B, respectively (p = 0.11). The mean age of the series was 46 years (17-55) (p =0.16). The mean follow-up of groups A and B were 9.9 (7-12) years and 9.7 (7-12) years, respectively (p =0.21). RESULTS: Mean Harris Hip Score improved from 55 to 92 in group A (p <0.001) and from 54 to 95 in group B (p <0.001), without differences between groups. Mean femoral neck length preservation in groups A and B was 13.6 (0-28) mm and 26 (11-38) mm, respectively (p =0.001). 13 (8.9%) and 1 (1%) patients in groups A and B presented postoperative complications, respectively (p =0.008). The conventional stem group had more aseptic loosening (Group A 3.4% vs. Group B 0%, p =0.06) along with more Symptomatic radiolucent lines (Group A 3.4% vs. Group B 0%, p =0.06). CONCLUSIONS: Both conventional and short stems showed excellent implant survival rates and functional outcomes at a mean follow-up of 9.8 years. However, complications and radiolucent lines were more frequent with a collarless conventional-length stem. Bone preservation of the femoral neck and diaphysis may be preferred in active young patients.

Alergia a la leche de vaca: ¿se pueden evitar las pruebas de provocación oral? Un análisis probabilístico basado en datos clínicos / Cow's milk allergy: Can oral food challenges be avoided? A probabilistic analysis based on clinical data

Introducción. La prueba de provocación oral (PPO) para el diagnóstico de alergia a las proteínas de la leche de la vaca (APLV) presenta riesgos y requiere de recursos. Nuestro objetivo fue evaluar condiciones y pruebas complementarias para identificar una alta probabilidad de APLV. Población y métodos. Análisis secundario sobre estudio de pacientes atendidos en una unidad de alergia entre 2015 y 2018. Se determinaron las probabilidades prepruebas asociadas a los síntomas y sus combinaciones, y las probabilidades pospruebas luego de realizadas pruebas cutáneas y determinación de inmunoglobulina E (IgE) sérica. Resultados. Se evaluó la información de 239 pacientes. Se observaron probabilidades mayores al 95 % en pacientes con angioedema y combinación de urticaria y vómitos. Usando puntos de corte propuestos por Calvani et al., la combinación de vómitos con rinitis, sin angioedema, también superó el 95 %. Conclusión. Se ofrece una metodología para identificar pacientes en los que puede diagnosticarse APLV sin realización de PPO.

Introduction. The oral food challenge (OFC) for the diagnosis of cow's milk protein allergy (CMPA) poses risks and requires resources. Our objective was to assess conditions and complementary tests used to identify a high probability of CMPA. Population and methods. Secondary analysis of a study of patients seen at a unit of allergy between 2015 and 2018. Pre-testing probabilities associated with symptoms and their combinations and post-testing probabilities after skin prick testing and serum immunoglobulin E (IgE) levels were determined. Results. The data from 239 patients were assessed. A probability greater than 95% was observed for angioedema and a combination of urticaria and vomiting. Based on the cut-off points proposed by Calvani et al., the combination of vomiting with rhinitis, without angioedema, also exceeded 95%. Conclusion. A methodology is provided to identify patients in whom CMPA may be diagnosed without an OFC.

Late Periprosthetic Femoral Stress Fracture Associated with Extra-articular Deformity in a Patient with Fibrous Dysplasia: A Case Report.

CASE: In the setting of a total hip arthroplasty performed in a patient with a proximal femoral deformity, atraumatic periprosthetic femoral stress fracture may arise as a complication. We report a rare case of a late periprosthetic femoral stress fracture around a cemented stem in a patient with a history of fibrous dysplasia of the proximal femur. After a 10-year uneventful period, the patient complained about a subtle, subacute pain in his left thigh induced by exercise but not with daily axial load. Diagnosis of a nondisplaced, incomplete (i.e., only compromising the lateral femoral cortex) periprosthetic femoral stress fracture was made with plain radiographs, blood work, and bone scintigraphy. Surgical treatment consisted of a minimally invasive plate osteosynthesis bridging the femoral deformity plus percutaneous osteoperiosteal decortication. At 5-year follow-up, the patient was asymptomatic with full return to physical activity, with radiographs evidencing callus formation. CONCLUSION: Stress fractures around well-fixed femoral stems, while infrequent, should be addressed in patients with a history of severe proximal femur deformity experiencing atraumatic thigh pain.

Acetabular Sector Angles in Asymptomatic and Dysplastic Hips: Defining Dysplasia and Thresholds to Guide Management.

BACKGROUND: Radiographic evaluation plays an important role in detecting and grading hip dysplasia. Acetabular sector angles (ASAs) measure the degree of femoral head coverage provided by the acetabulum on computed tomographic (CT) scans. In this study, we aimed to determine ASA values at different axial levels in a control cohort with asymptomatic, high-functioning hips without underlying hip pathology and a study group with symptomatic, dysplastic hips that underwent periacetabular osteotomy (PAO), thereby defining the ASA thresholds for hip dysplasia. METHODS: This was a cross-sectional study evaluating a control group of 51 patients (102 hips) and a study group of 66 patients (72 hips). The control group was high-functioning and asymptomatic, with an Oxford Hip Score of >43, did not have osteoarthritis (Tönnis grade ≤1), underwent a pelvic CT scan, had a mean age (and standard deviation) of 52.1 ± 5.5 years, and was 52.9% female. The study group had symptomatic hip dysplasia treated with PAO, had a mean age of 29.5 ± 7.3 years, and 83.3% was female. Anterior ASA (AASA) and posterior ASA (PASA) were measured at 3 axial CT levels to determine equatorial, intermediate, and proximal ASA. The thresholds for dysplasia were determined using receiver operating characteristic (ROC) curve analysis, including the area under the curve (AUC). RESULTS: Patients with dysplasia had significantly smaller ASAs compared with the control group; the differences were most pronounced for proximal AASAs and proximal and intermediate PASAs. The control group had a mean proximal PASA of 162° ± 17°, yielding a threshold for dysplasia of 137° (AUC, 0.908). The mean intermediate PASA for the control group was 117° ± 11°, yielding a threshold of 107° (AUC, 0.904). The threshold for anterior dysplasia was 133° for proximal AASA (AUC, 0.859) and 57° for equatorial AASA (AUC, 0.868). The threshold for posterior dysplasia was 102° for intermediate PASA (AUC, 0.933). CONCLUSIONS: Measurement of ASA is a reliable tool to identify focal acetabular deficiency with high accuracy, aiding diagnosis and management. A proximal PASA of <137° or an intermediate PASA of <107° should alert clinicians to the presence of dysplasia. LEVEL OF EVIDENCE: Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Stenotrophomonas maltophilia Periprosthetic Joint Infection after Hip Revision Arthroplasty.

Stenotrophomonas maltophilia, a well-established opportunistic bacterium, primarily impacts healthcare settings. Infection of the musculoskeletal system with this bacterium is rare. We report on the first known case of hip periprosthetic joint infection (PJI) caused by S. maltophilia. The potential for development of a PJI caused by this pathogen should be considered by orthopaedic surgeons, particularly in patients with multiple severe comorbidities.

Cow's milk allergy: Can oral food challenges be avoided? A probabilistic analysis based on clinical data. / Alergia a la leche de vaca: ¿se pueden evitar las pruebas de provocación oral? Un análisis probabilístico basado en datos clínicos.

Introduction. The oral food challenge (OFC) for the diagnosis of cow's milk protein allergy (CMPA) poses risks and requires resources. Our objective was to assess conditions and complementary tests used to identify a high probability of CMPA. Population and methods. Secondary analysis of a study of patients seen at a unit of allergy between 2015 and 2018. Pre-testing probabilities associated with symptoms and their combinations and post-testing probabilities after skin prick testing and serum immunoglobulin E (IgE) levels were determined. Results. The data from 239 patients were assessed. A probability greater than 95% was observed for angioedema and a combination of urticaria and vomiting. Based on the cut-off points proposed by Calvani et al., the combination of vomiting with rhinitis, without angioedema, also exceeded 95%. Conclusion. A methodology is provided to identify patients in whom CMPA may be diagnosed without an OFC.

Introducción. La prueba de provocación oral (PPO) para el diagnóstico de alergia a las proteínas de la leche de la vaca (APLV) presenta riesgos y requiere de recursos. Nuestro objetivo fue evaluar condiciones y pruebas complementarias para identificar una alta probabilidad de APLV. Población y métodos. Análisis secundario sobre estudio de pacientes atendidos en una unidad de alergia entre 2015 y 2018. Se determinaron las probabilidades prepruebas asociadas a los síntomas y sus combinaciones, y las probabilidades pospruebas luego de realizadas pruebas cutáneas y determinación de inmunoglobulina E (IgE) sérica. Resultados. Se evaluó la información de 239 pacientes. Se observaron probabilidades mayores al 95 % en pacientes con angioedema y combinación de urticaria y vómitos. Usando puntos de corte propuestos por Calvani et al., la combinación de vómitos con rinitis, sin angioedema, también superó el 95 %. Conclusión. Se ofrece una metodología para identificar pacientes en los que puede diagnosticarse APLV sin realización de PPO.

Anterior Center-Edge Angle Is Less Reliable Than Anterior Wall Index to Predict Anterior Coverage of the Femoral Head.

BACKGROUND: No consensus is available regarding which radiographic measurement most accurately correlates with anterior coverage of the femoral head. PURPOSE: (1) To determine the correlation between 2 measurements of anterior wall coverage: total anterior coverage (TAC) calculated from radiographs and equatorial anterior acetabular sector angle (eAASA) calculated from computed tomography (CT) scans; (2) to define the correlation between anterior center-edge angle (ACEA) and anterior wall index (AWI) with TAC and eAASA; and (3) to investigate what other radiographic metrics may help predict anterior coverage. STUDY DESIGN: Cohort study (Diagnosis); Level of evidence, 3. METHODS: The authors retrospectively reviewed 77 hips (48 patients) for which radiographs and CT scans were obtained for reasons other than hip-related pain. Mean age of the population was 62 ± 22 years; 48 (62%) hips were from female patients. Two observers measured lateral center-edge angle (LCEA), AWI, Tönnis angle, ACEA, CT-based pelvic tilt, and CT-based acetabular version, with all Bland-Altman plots within 95% agreement. Correlation between intermethod measurements was estimated with a Pearson coefficient. Linear regression was used to test the ability of baseline radiographic measurements to predict both TAC and eAASA. RESULTS: Pearson coefficients were r = 0.164 (ACEA vs TAC; P = .155), r = 0.170 (ACEA vs eAASA; P = .140), r = 0.58 (AWI vs TAC; P = .0001), and r = 0.693 (AWI vs eAASA; P < .0001). Multiple linear regression model 1 showed that AWI (ß = 17.8; 95% CI, 5.7 to 29.9; P = .004), CT acetabular version (ß = -0.45; 95% CI, -0.71 to -0.22; P = .001), and LCEA (ß = 0.33; 95% CI, 0.19 to 0.47; P = .001) were useful to predict TAC. Multiple linear regression model 2 revealed that AWI (ß = 25; 95% CI, 15.67 to 34.4; P = .001), CT acetabular version (ß = -0.48; 95% CI, -0.67 to -0.29; P = .001), CT pelvic tilt (ß = 0.26; 95% CI, 0.12 to 0.4; P = .001), and LCEA (ß = 0.21; 95% CI, 0.1 to 0.3; P = .001) accurately predicted eAASA. Model-based estimates and 95% CIs using 2000 bootstrap samples from the original data were 6.16 to 28.6 for AWI in model 1 and 15.1 to 34.26 for AWI in model 2. CONCLUSION: There was a moderate to strong correlation between AWI and both TAC and eAASA, whereas ACEA correlated weakly with the former measurements, thus not being useful to quantify anterior acetabular coverage. Other variables such as LCEA, acetabular version, and pelvic tilt may also help predict anterior coverage in asymptomatic hips.

Do nonagenarians have more complications and unplanned readmissions than octogenarians following primary THA? A retrospective cohort study.

INTRODUCTION: The performance of total hip arthroplasty in elderly patients, especially nonagenarians, is challenging due to higher patient frailty and medical comorbidities. We compared 90-day postoperative complications and unplanned readmissions between nonagenarians and octogenarians undergoing elective THA. METHODS: One hundred and eleven patients undergoing elective, unilateral THA were retrospectively analyzed. Forty-four patients were nonagenarians (Group A), and 67 patients were octogenarians (Group B). Demographic data included age, gender, body mass index (BMI), ASA score and Charlson Comorbidity Index (CCI). Frailty was defined according to the Rockwood Frailty Index. All patients underwent a thorough preoperative assessment through a specific institutional clinical pathway created for this matter. Postoperative adverse events were grouped into major or minor. A regression model was used to evaluate independent risk factors for the development of complications. RESULTS: There were no differences in the ASA score (65.9% vs. 53.7% ASA III-IV), prevalence of frailty (1% vs. 9%) and comorbidities between both groups (p > .05). The CCI was higher in nonagenarians (p = 0.007). Nonagenarians had more in-hospital complications, although most were minor (p = 0.002), none of which resulted in mortality. Ninety-day unplanned readmissions were similar between groups, with 4 (9.1%) and 6 (9%) in groups A and B, respectively (p = 1). Although age was a factor associated with the development of postoperative complications in the univariate regression model (OR 3.81, 95% CI 1.31 to 11.11, p = 0.014), it lost significance after performing the multivariate analysis (OR 2.48, 95% CI 0.78 to 7.90, p = 0.125). CONCLUSION: The age of 90 years old was not a barrier to perform elective THA safely. Nonagenarians had higher in-hospital minor complications when compared to the younger cohort. However, age over 90 years was not an independent risk factor for unplanned readmissions or mortality. Multimodal protocols of perioperative care are paramount for improving outcomes after THA in very old patients.

Latin American anaphylaxis registry.

Background: Recent data about clinical features, triggers and management of anaphylaxis in Latin America is lacking. Objective: To provide updated and extended data on anaphylaxis in this region. Method: An online questionnaire was used, with 67 allergy units involved from 12 Latin-American countries and Spain. Among data recorded, demographic information, clinical features, severity, triggering agents, and treatment were received. Results: Eight hundred and seventeen anaphylactic reactions were recorded. No difference in severity, regardless of pre-existing allergy or asthma history was found. Drug induced anaphylaxis (DIA) was most frequent (40.6%), followed by food induced anaphylaxis (FIA) (32.9%) and venom induced anaphylaxis (VIA) (12%). FIA and VIA were more common in children-adolescents. Non-steroidal anti-inflammatory drugs (NSAIDs) and beta-lactam antibiotics (BLA) were the most frequent drugs involved. Milk (61.1% of FIA) and egg (15.4% of FIA) in children, and shellfish (25.5% of FIA), fresh fruits (14.2% of FIA), and fish (11.3% of FIA) in adults were the most common FIA triggers. Fire ants were the most frequent insect triggers, and they induced more severe reactions than triggers of FIA and DIA (p < 0.0001). Epinephrine was used in 43.8% of anaphylaxis episodes. After Emergency Department treatment, epinephrine was prescribed to 13% of patients. Conclusions: Drugs (NSAIDs and BLA), foods (milk and egg in children and shellfish, fruits and fish in adults) and fire ants were the most common inducers of anaphylaxis. Epinephrine was used in less than half of the episodes emphasizing the urgent need to improve dissemination and implementation of anaphylaxis guidelines.

Intraoperative unfractionated heparin before femoral component cementation should be avoided in femoral neck fracture treated with hybrid total hip arthroplasty.

PURPOSE: To compare the incidence of perioperative thromboembolic events in femoral neck fracture (FNF) patients treated with hybrid total hip arthroplasty (THA) with intraoperative unfractionated heparin (UFH) versus a control group without intraoperative UFH before femoral component cementation. METHODS: We compared 139 cases without UFH (group A) versus 134 who received 10 UI/kg UFH (group B). Indication of UFH before cementation depended on the preferences of the anaesthesiologists in each case. We assessed intraoperative bone cement implantation syndrome (BCIS) and 30-day thromboembolic events, and 90-day and 1-year mortality. BCIS was classified as per Donaldson et al.'s classification according to the degree of hypotension, arterial desaturation or loss of consciousness. RESULTS: BCIS was observed in 51 (18%) cases, including 37 (13%) grade 1 and 14 (5%) grade 2. Forty-seven BCISs (35%) were observed in group B and 4 (3%) in group A (p < 0.001). Multivariate regression showed that intraoperative UFH (OR = 18, CI 95% 6-52) and consumption of oral anticoagulants (OR = 3.3, CI 95% 1-10) increased the risk of BCIS. Five patients further developed a 30-day pulmonary embolism in group B, while 2 presented this complication in group A (p = 0.231). No association between BCIS and 30-day thromboembolic events was found (p = 0.62). 90-day (1% each, p = 0.98) and 1-year (2% vs. 3%, p = 0.38) mortality were similar. CONCLUSIONS: BCIS was a frequent finding in FNF patients treated with hybrid THA. We found a paradoxically significant increase in BCIS with the use of UFH. Heparin did not seem to prevent BCIS, other thromboembolic events and mortality in this group of patients.

Cerclage wire or positional cortical screw for the treatment of intraoperative calcar fractures during primary total hip arthroplasty? A biomechanical study.

BACKGROUND: During primary total hip arthroplasty, intra-operative calcar fractures have been historically treated with cerclage wires. However, interfragmentary screw fixation technique can possibly achieve the same results with technical advantages. The aim of this biomechanical study was to assess stability of calcar fractures fixed using interfragmentary screw technique compared to a traditional cerclage system specifically in context of total hip arthroplasty. METHODS: Thirty-two periprosthetic fractures were reduced using either a single cerclage cable or an intracortical positional screw perpendicular to the fracture line. Axial and torsional load testing was terminated after experimental model failure. FINDINGS: No significant difference was obtained for all output parameters when comparing cerclage wires versus interfragmentary screw fixation respectively. Load at failure: 8043 ± 712 N vs 7425 ± 854 N (p = 0.115). Load at calcar fracture propagation: 6240 ± 2207 N versus 6220 ± 966 N (p = 0.668). Maximum stiffness before failure: 617 ± 115 N/mm vs 839 ± 175 N/mm (p = 0.100) and stiffness at calcar fracture propagation reached 771 ± 153 Nmm vs 886 ± 129 N/mm (p = 0.197). Torque to failure levels obtained were 59.4 ± 7.1 N*m vs 60.9 ± 12.0 N*m (p = 0.908). Torque to calcar fracture propagation, 51.6 ± 6.1 N*m vs 48.5 ± 9.8 N*m (p = 0.298). Torsional stiffness at failure, 0.38 ± 0.03 N*m\deg. vs 0.43 ± 0.13 N*m\deg. (p = 0.465). Torsional stiffness at calcar fracture propagation were 0.37 ± 0.03 N*m\deg. vs 0.45 ± 0.17 N*m\deg. (p = 0.462). INTERPRETATION: The strength of fixation and stability of the implant were similar for both techniques. In the synthetic bone model tested, using an interfragmentary screw conveyed similar stability to the constructs in the management of an intra-operative medial calcar fractures. Thus, potentially giving surgeons an alternative option for intraoperative fracture fixation during primary total hip arthroplasty.

Acetabular coverage analysis of the proximal femoral head accurately characterizes dysplastic acetabular morphology.

This study aimed to (1) measure acetabular sector angle (ASA) from proximal to distal positions along the axial femoral head axis, (2) identify acetabular deficiency patterns, and (3) correlate ASA at different axial positions with other radiological measurements in acetabular dysplasia. We identified 30 hips with dysplasia (lateral center edge angle [LCEA] <20°) and 30 hips without dysplasia (LCEA >25°) from a retrospective cohort. Anterior and posterior ASA (AASA, PASA) were measured in the axial computed tomography plane through the femoral head center (equatorial) and two axial positions above the equatorial line (intermediate and proximal). Deficiency patterns were identified using ASA cut-off values determined from receiver operating characteristic curves. Pearson's coefficients were used for correlations. Compared to non-dysplastic hips, AASA in dysplastic hips was significantly smaller in all levels: equatorial (46.1 ± 7.3 vs. 54.9 ± 8.5,° p < 0.001), intermediate (62.1 ± 11.2 vs. 69.0 ± 10.6,° p = 0.02), and proximal (102.9 ± 14.2 vs. 128.3 ± 23.0,° p < 0.001). According to proximal ASA (Pro-ASA) cut-off values in dysplastic hips, global deficiency was most prevalent (19/30, 63.3%), followed by anterior (6/30, 20%) and posterior (3/30, 10%) deficiency. There were strong correlations between acetabular anteversion and Eq-AASA (r = -0.74, p < 0.001) and LCEA and pro-PASA (r = 0.82, p < 0.001). Clinical significance: Acetabular sector angle provides insight into acetabular morphology and patterns of deficiency, providing essential information for precise acetabular reorientation.

[Classification of food allergy: generalities]. / Clasificación de la alergia alimentaria: generalidades.

The prevalence of food allergy has increased in some regions of the world, and with it the incidence, according to geographical variability, in the phenotype and clinical manifestations. Food allergy arises from the specific immune response induced by exposure to the proteins of a certain food. Food intolerance refers to non-immune reactions, caused by unique physiological characteristics of the individual, including metabolic, toxic, pharmacological and undefined mechanisms. Adverse reactions to foods are classified as: IgE-mediated: Type I Hypersensitivity, non-IgE-mediated: Type IV Hypersensitivity, mixed: Types I and IV Hypersensitivity Non-Allergic; toxic, pharmacological, metabolic, intolerances. These types of alterations are rare but have increased in recent years; These include protein-induced enterocolitis syndrome, which can cause emesis, diarrhea and hypotension, and shock, which begins two hours after ingestion of the allergen. Protein-induced allergic proctocolitis is a condition that includes allergy to cow's milk protein. Delayed reactions usually affect the digestive system, are more insidious in their onset and are not immediately controlled, even with the suspension of food. There are eight foods responsible for 90% of food allergies: milk, eggs, soy, wheat, peanuts, walnuts, fish, and shellfish.

La prevalencia de alergia alimentaria se ha incrementado en algunas regiones del mundo, y con ello la incidencia, según la variabilidad geográfica, en el fenotipo y manifestaciones clínicas. La alergia alimentaria surge de la respuesta inmune específica inducida por la exposición a las proteínas de cierto alimento. La intolerancia alimentaria se refiere a reacciones no inmunitarias, causadas por características fisiológicas únicas del individuo, que incluyen mecanismos metabólicos, tóxicos, farmacológicos e indefinidos. Las reacciones adversas a los alimentos se clasifican en: mediada por IgE: Hipersensibilidad Tipo I, no mediada por IgE: Hipersensibilidad Tipo IV, mixtas: Hipersensibilidad Tipos I y IV No Alérgicas; tóxicas, farmacológicas, metabólicas, intolerancias. Este tipo de alteraciones son poco frecuentes, pero se ha incrementado en los últimos años; entre estas se encuentra el síndrome de enterocolitis inducida por proteínas, que puede producir emesis, diarrea e hipotensión, y estado de shock, que inicia dos horas después de la ingestión del alergeno. La proctocolitis alérgica inducida por proteínas es una afectación que incluye la alergia a la proteína de leche de vaca. Las reacciones retardadas suelen afectar el aparato digestivo, son más insidiosas en su inicio y no se controlan inmediatamente, aún con la suspensión del alimento. Existen ocho alimentos responsables del 90% de alergia alimentaria: leche, huevo, soya, trigo, cacahuate, nuez, pescados y mariscos.

Vástagos femorales cortos para el reemplazo total de cadera primario en pacientes jóvenes. Resultados clínicos y biomecánicos / Short femoral stems for primary total hip arthroplasty in young patients. Clinical and biomechanical outcomes

La artroplastia total de cadera es una cirugía eficaz para tratar la artrosis. Con el aumento de la necesidad de una mejor calidad de vida, este procedimiento se está realizando en pacientes más jóvenes. Pero, con la mayor expectativa de vida, también crece la demanda de múltiples cirugías de revisión para el mismo paciente. Esto plantea desafíos técnicos debido a la pérdida de hueso. Existe una necesidad creciente de identificar implantes duraderos y altamente funcionales que sean adecuados para la revisión futura. Aunque los vástagos femorales cementados eran la opción principal en el pasado, los vástagos femorales no cementados han logrado una fijación a largo plazo y excelentes resultados. Sin embargo, aún se pueden mejorar algunos problemas relacionados con la fijación. Los vástagos femorales cortos han sido desarrollados para abordar algunos de estos desafíos, mientras se mantienen los buenos resultados obtenidos con los vástagos convencionales. En este artículo, se analiza la experiencia tras 10 años de uso de vástagos femorales cortos en cirugías de cadera en pacientes jóvenes. Se comparan los resultados biomecánicos y la preservación ósea femoral, se reportan los resultados posoperatorios en relación con el regreso al deporte, y se evalúan las complicaciones relacionadas con su uso. El empleo de vástagos cortos en cirugía primaria de cadera brinda múltiples ventajas. La indicación de este tipo de implante está justificada en pacientes jóvenes y activos, con el objetivo de reproducir los resultados de los implantes convencionales con un menor consumo de hueso y la posibilidad de una revisión futura. Nivel de Evidencia: IV

Total hip arthroplasty is an effective surgery to treat osteoarthritis. Given the rising demand for a higher quality of life, this procedure is being performed on increasingly younger patients. However, a longer life expectancy is also tied to a higher demand for multiple revision surgeries for the same patient. This poses technical challenges due to bone loss. There is a growing need to identify durable and highly functional implants that are suitable for future revision. Although cemented femoral stems were the main option in the past, uncemented femoral stems have demonstrated long-term fixation and excellent results. However, some issues related to fixation can still be improved. Short femoral stems have been developed to address some of these challenges while maintaining the good results obtained with conventional stems. This study analyzes the experience after 10 years of using short femoral stems in hip surgeries on young patients. Biomechanical outcomes and femoral bone preservation are compared, postoperative outcomes regarding return to sports are reported, and complications related to their use are evaluated. Short stems have multiple advantages when used in primary hip surgery. The indication for this type of implant is justified in young and active patients, to reproduce the results of conventional implants with less bone consumption and the possibility of future revision. Level of Evidence: IV

Successful hip revision surgery following refracture of a modern femoral stem using a cortical window osteotomy technique: A case report and review of literature.

BACKGROUND: The ExeterTM Universal cemented femoral component is widely used for total hip replacement surgery. Although there have been few reports of femoral component fracture, removal of a broken femoral stem can be a challenging procedure. CASE SUMMARY: A 54-year-old man with a Dorr A femur sustained a refracture of a primary ExeterTM stem, two years after receiving a revision using a cement-within-cement technique (CWC) through an extended trochanteric osteotomy (ETO). The technical problems related to the CWC technique and the ETO played a major role in the stem fatigue refracture. We performed revision surgery and removed the distal cement using a cortical femoral window technique, followed by re-implantation with an uncemented, modular, distally-fixed uncemented stem. The patient experienced an uneventful postoperative recovery. CONCLUSION: Re-fracture of a modern femoral ExeterTM stem is a rare event, but technical complications related to revision surgery can lead to this outcome. The cortical window osteotomy technique can facilitate the removal of a broken stem and cement, allowing for prosthetic re-implantation under direct vision and avoiding ETO-related complications.

Feasibility of total hip arthroplasty in cerebral palsy patients: a systematic review on clinical outcomes and complications.

PURPOSE: Total hip arthroplasty (THA) is a successful treatment for hip osteoarthritis secondary to hip dysplasia. However, the reported rate of complications following THA in the settings of neuromuscular diseases is high. This systematic review aimed to analyze the indications, functional outcomes and surgical failures of primary THA in cerebral palsy (CP) patients. METHODS: MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews were searched, and all clinical studies focusing on THA in patients with CP from inception through March 2020 were included. The methodological quality was assessed with Guo et al.'s quality appraisal checklist for case series and case-control studies, while cohort and prospective studies were evaluated with a modified version of the Downs and Black's quality assessment checklist. RESULTS: The initial search returned 69 studies out of which 15, including 2732 THAs, met the inclusion criteria. The most frequent indication for THA was dislocated painful hip for which previous non-operative treatment had failed. Complications presented in 10 to 45% of cases. The most frequently reported complication was dislocation (1-20%), followed by component loosening (0.74-20%). Aseptic component loosening was the most frequent cause of revision surgery, followed by dislocation and periprosthetic fracture. Mean implant survival at ten years was 84% (range 81-86%). CONCLUSION: The available literature suggests that although THA is a beneficial procedure in CP patients, it has a higher rate of complications and worse implant survival than the general population.

Adverse Local Tissue Reaction Associated With Ceramic-On-Metal Bearing Surface in Primary Total Hip Arthroplasty: Report of Two Cases.

Total hip arthroplasty (THA) is one of the most common and successful surgical procedures worldwide. At the same time, it is constantly evolving, and as a consequence, advances in implant technology have led to significant improvements in the different materials of the acetabular and femoral components. The selection of bearing surfaces and their tribology are critical to achieving a successful outcome. Pseudotumors are important, and usually misdiagnosed, complications associated with hard bearing surfaces such as metal-on-metal couples. They belong to a group of reactions called adverse local tissue reaction, which can occur in the vicinity of any THA. We present 2 cases of adverse local tissue reaction associated with the use of ceramic-on-metal bearings surfaces in 2 primary THAs that were treated with modular component exchange during single-stage revision surgery. Level of Evidence: IV.

Impaction Bone Grafting for Severe Femoral Bone Loss: Surgical Technique in Revision Total Hip Arthroplasty.

Revision total hip arthroplasty in the setting of extensive femoral bone loss poses a considerable challenge to the adult reconstructive surgeon. When the proximal femoral bone stock is deficient or absent, there are few options for reconstruction. In such cases, treatment options include distal cementless fixation (either modular or nonmodular), impaction bone grafting (IBG), a megaprosthesis, or even an allograft-prosthesis composite. Each of these procedures has advantages and disadvantages related to bone preservation, surgical timing, and complexity (depending on the learning curve). For its capacity of restoring bone stock, we have been utilizing the IBG technique at our center since August 1987. The aim of the present article was to describe a step-by-step femoral IBG procedure for severe proximal femoral circumferential bone loss, highlighting its current indications and contraindications. Description: The specific steps to perform this procedure include (1) preoperative planning; (2) positioning of the patient and surgical approach; (3) cautious removal of the previous components; (4) preparation of the bone graft; (5) implantation of the appropriate IBG revision system, restoring bone loss from distal to proximal and utilizing metal mesh as needed; (6) implantation of the new stem, bypassing the defect; and (7) aftercare with protected weight-bearing in order to avoid subsidence of the stem and periprosthetic fracture. Alternatives: There are several alternatives to the IBG technique in the setting of revision total hip arthroplasty with extensive femoral bone loss. These alternatives include distal cementless fixation (either modular or nonmodular), a megaprosthesis, or an allograft-prosthesis composite. Rationale: The rationale for use of the IBG technique is restoration of bone stock. Although this issue may be irrelevant in low-demand elderly patients, we believe it is of the utmost importance among young (i.e., <60 years old) and active patients. This technique is versatile enough to be utilized in different scenarios such as periprosthetic fracture, periprosthetic joint infection (2-stage protocols), and aseptic loosening. Expected Outcomes: We have reported favorable clinical and radiographic outcomes for the treatment of both aseptic and septic femoral component loosening. In all cases, we utilized vancomycin-supplemented impacted cancellous allograft without evidence of secondary effects with regard to bone incorporation, nephrotoxicity, or allergic reactions. Although it was initially contraindicated, we further extended the indication for this reconstruction alternative to cases of circumferential proximal bone loss with non-neoplastic bone defects of ≤15 cm, utilizing encompassing metal mesh and a bypassing long stem. Recently, we reported on poorer outcomes following IBG compared with the use of uncemented modular stems for the treatment of type B3 periprosthetic femoral fractures, with a significantly higher rate of infection and implant breakage for the former treatment. Nowadays, we advocate the use of this technique in young, active patients (i.e., <60 years old) with a femoral bone defect Paprosky grade IIIB or IV, in which reconstitution of bone stock is crucial to avoid an eventual implant failure in the long term. Important Tips: This technique requires an experienced team. This procedure should be avoided in the presence of active periprosthetic joint infection.The gluteus maximus tendon should be detached to avoid tensioning the sciatic nerve and to decrease the chance of periprosthetic femoral fracture.Massive bone loss can jeopardize correct implant orientation and restoration of biomechanics. In this scenario, surgeons might consider the intercondylar axis as a guide for femoral version.Try to avoid (if possible) trochanteric or extended trochanteric osteotomy because proximal bone stock is necessary to contain the bone grafts. In some cases, such as those in which the removal of the stem is difficult, especially with certain uncemented stem designs, an extended trochanteric osteotomy must be performed. Whether or not a cemented stem is removed, it is mandatory to remove all remaining cement in the femoral canal.Preoperative templating is a necessity to reconstruct leg length. Accurately determining the length of the mesh is the most important step to avoid shortening or overlengthening of the lower extremity.Approximately 10 cm of circumferential metal mesh should be fixed with 3 to 5 double cerclage metal wires to the remaining bone. The new femoral stem should bypass extend beyond the mesh for approximately 5 cm. If the stem does not bypass the mesh, there is an increased risk of postoperative fracture.In order to decrease the risk of intraoperative femoral fracture, the distal aspect of the femur should be secured with cerclage wires, and the proximal aspect of the femur should also be protected with cerclage wires over the mesh. As in any other complex femoral revision procedure, torsional forces in the supracondylar zone should be avoided, especially during trial or stem reduction maneuvers.Always utilize a bone graft mixed with antibiotic powder.Retrograde cementation must be done with cement that is in a more liquid state than in primary total hip arthroplasty. Acronyms & Abbreviations: PO = postoperativePMMA = polymethyl methacrylateIV = intravenousLMWH = low molecular weight heparinDVT/EP = deep vein thrombosis and extended prophylaxis.

Utilidad de las pruebas analíticas en el diagnóstico de alergia a las proteínas de la leche de vaca / Usefulness of analytic tests for the diagnosis of cow's milk protein allergy

Introducción. La alergia a las proteínas de la leche de vaca es la alergia alimentaria más frecuente en los niños y para su diagnóstico se emplean historia clínica dirigida y prueba de provocación oral (PPO), el dosaje sérico de inmunoglobulina E específica (sIgE) y pruebas cutáneas de puntura (SPT, por su sigla en inglés). Sin embargo, su utilidad diagnóstica es difícil de establecer en la población local. El objetivo fue evaluar la utilidad de las pruebas para el diagnóstico de alergia a las proteínas de la leche de vaca (PLV) en la población estudiada. Población y métodos. Análisis retrospectivo de datos de pacientes atendidos en la Unidad de Alergia del Hospital Elizalde entre 2015 y 2018. Se evaluaron SPT y sIgE para leche, alfa-lactoalbúmina, beta-lactoglobulina y caseína, seguidos de PPO y se determinó la utilidad diagnóstica para cada prueba, y sus combinaciones. Resultados. Se evaluaron las pruebas de 239 pacientes. La PPO fue hospitalaria en el 54,8 % de los casos, por reexposición domiciliara en el 35,5 % y en el 9,6 % por incorporación de PLV a la madre. La mayor especificidad fue la de SPT con caseína (96,7 %; intervalo de confianza [IC95%]: 90,8-99,3) y la mayor sensibilidad, la de la combinación de SPT y sIgE con los 4 alérgenos (55,3 %; IC95%: 45,7-64,6). Conclusiones. El trabajo estableció la utilidad diagnóstica de las SPT y el sIgE en la población estudiada.

Introduction. Cow's milk protein allergy is the most common food allergy among children. It can be diagnosed based on a guided history taking and using an oral food challenge (OFC), serum specific immunoglobulin E levels (sIgE), and skin prick tests (SPT). However, it is difficult to establish their diagnostic performance in the local population. Our objective was to assess the usefulness of tests used to diagnose cow's milk protein (CMP) allergy in the studied population. Population and methods. Retrospective analysis of data from patients seen at the Unit of Allergy of a tertiary care pediatric hospital between 2015 and 2018. SPT and sIgE tests were done for milk, alpha-lactalbumin, beta-lactoglobulin, and casein, followed by an OFC, and the diagnostic usefulness of each test, as well as their combination, was established. Results. The tests of 239 patients were assessed. OFC was performed at the hospital in 54.8 % of cases, via a rechallenge test at home in 35.5 %, and through CMP intake by the mother in 9.6 %. The highest specificity was observed with the casein SPT (96.7 %; 95 % confidence interval [CI]: 90.8-99.3) and the highest sensitivity, with the 4-allergen SPT and sIgE combination (55.3 %; 95 % CI: 45.7-64.6). Conclusions. The study established the diagnostic usefulness of SPT and sIgE in the studied population.