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1.
Diabetol Metab Syndr ; 16(1): 106, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769575

RESUMEN

OBJECTIVE: To establish recommendations through the consensus of a Latin American experts panel on the use of the flash glucose monitoring system (fCGM) in people living with type 2 diabetes mellitus (T2DM) regarding the benefits and challenges of using the fCGM. METHODS: An executive committee of experts was created, comprised by a panel of fifteen physicians, including endocrinologists and internal medicine physicians, with expertise in management of adult patients with T2DM. The experts were from various countries: Colombia, Chile, Peru, Mexico, Argentina, and Brazil. The modified Delphi method was used, considering a consensus level of at least 80% of the participants. A seventeen-item instrument was developed to establish recommendations on the use of fCGM in patients with T2DM in Latin American. RESULTS: The number of glucose scans recommended per day with the fCGM for patients managed with oral antidiabetic drugs or basal insulin was a median of 6 scans per day, and for those managed with multiple insulin doses, a median of 10 scans per day was recommended. Additionally, a holistic and individualized management approach was recommended, taking into account new treatment directions and identifying patients who would benefit from the use of the fCGM. CONCLUSION: Continuous use of the fCGM is recommended for people living with T2DM, regardless of their type of treatment. These metrics must be evaluated individually for each patient profile.

2.
J Orthop Res ; 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38669091

RESUMEN

Patient-specific flanged acetabular components are utilized to treat failed total hip arthroplasties with large acetabular defects. Previous clinical studies from our institution showed that these implants tend to lateralize the acetabular center of rotation. However, the clinical impact of lateralization on implant survivorship is debated. Our goal was to develop a finite element model to quantify how lateralization of the native hip center affects periprosthetic strain and implant-bone micromotion distributions in a static level gait loading condition. To build the model, we computationally created a superomedial acetabular defect in a computed tomography 3D reconstruction of a native pelvis and designed a flanged acetabular implant to address this simulated bone defect. We modeled two implants, one with ~1 cm and a second with ~2 cm of hip center lateralization. We applied the maximum hip contact force and corresponding abductor force observed during level gait. The resulting strains were compared to bone fatigue strength (0.3% strain) and the micromotions were compared to the threshold for bone ingrowth (20 µm). Overall, the model demonstrated that the additional lateralization only slightly increased the area of bone at risk of failure and decreased the areas compatible with bone ingrowth. This computational study of patient-specific acetabular implants establishes the utility of our modeling approach. Further refinement will yield a model that can explore a multitude of variables and could be used to develop a biomechanically-based acetabular bone loss classification system to guide the development of patient-specific implants in the treatment of large acetabular bone defects.

3.
J Arthroplasty ; 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38548236

RESUMEN

BACKGROUND: Cementless total knee arthroplasty (TKA) has regained interest for its potential for long-term biologic fixation. The density of the bone is related to its ability to resist static and cyclic loading and can affect long-term implant fixation; however, little is known about the density distribution of periarticular bone in TKA patients. Thus, we sought to characterize the bone mineral density (BMD) of the proximal tibia in TKA patients. METHODS: We included 42 women and 50 men (mean age 63 years, range: 50 to 87; mean body mass index 31.6, range: 20.5 to 49.1) who underwent robotic-assisted TKA and had preoperative computed tomography scans with a BMD calibration phantom. Using the robotic surgical plan, we computed the BMD distribution at 1 mm-spaced cross-sections parallel to the tibial cut from 2 mm above the cut to 10 mm below. The BMD was analyzed with respect to patient sex, age, preoperative alignment, and type of fixation. RESULTS: The BMD decreased from proximal to distal. The greatest changes occurred within ± 2 mm of the tibial cut. Age did not affect BMD for men; however, women between 60 and 70 years had higher BMD than women ≥ 70 years for the total cut (P = .03) and the medial half of the cut (P = .03). Cemented implants were used in 1 86-year-old man and 18 women (seven < 60 years, seven 60 to 70 years, and four ≥ 70 year old). We found only BMD differences between cemented or cementless fixation for women < 60 years. CONCLUSIONS: To our knowledge, this is the first study to characterize the preoperative BMD distribution in TKA patients relative to the intraoperative tibial cut. Our results indicate that while sex and age may be useful surrogates of BMD, the clinically relevant thresholds for cementless knees remain unclear, offering an area for future studies.

4.
J Biomech ; 164: 111973, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38325192

RESUMEN

Computational studies of total knee arthroplasty (TKA) often focus on either joint mechanics (kinematics and forces) or implant fixation mechanics. However, such disconnect between joint and fixation mechanics hinders our understanding of overall TKA biomechanical function by preventing identification of key relationships between these two levels of TKA mechanics. We developed a computational workflow to holistically assess TKA biomechanics by integrating musculoskeletal and finite element (FE) models. For our initial study using the workflow, we investigated how tibiofemoral contact mechanics affected the risk of failure due to debonding at the implant-cement interface using the four available subjects from the Grand Challenge Competitions to Predict In Vivo Knee Loads. We used a musculoskeletal model with a 12 degrees-of-freedom knee joint to simulate the stance phase of gait for each subject. The computed tibiofemoral joint forces at each node in contact were direct inputs to FE simulations of the same subjects. We found that the peak risk of failure did not coincide with the peak joint forces or the extreme tibiofemoral contact positions. Moreover, despite the consistency of joint forces across subjects, we observed important variability in the profile of the risk of failure during gait. Thus, by a combined evaluation of the joint and implant fixation mechanics of TKA, we could identify subject-specific effects of joint kinematics and forces on implant fixation that would otherwise have gone unnoticed. We intend to apply our workflow to evaluate the impact of implant alignment and design on TKA biomechanics.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Humanos , Fenómenos Biomecánicos , Flujo de Trabajo , Rango del Movimiento Articular , Articulación de la Rodilla/cirugía
5.
J Arthroplasty ; 39(5): 1323-1327, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38000515

RESUMEN

BACKGROUND: Cementless tibial baseplates in total knee arthroplasty include fixation features (eg, pegs, spikes, and keels) to ensure sufficient primary bone-implant stability. While the design of these features plays a fundamental role in biologic fixation, the effectiveness of anterior spikes in reducing bone-implant micromotion remains unclear. Therefore, we asked: Can an anterior spike reduce the bone-implant micromotion of cementless tibial implants? METHODS: We performed computational finite element analyses on 13 tibiae using the computed tomography scans of patients scheduled for primary total knee arthroplasty. The tibiae were virtually implanted with a cementless tibial baseplate with 2 designs of fixation of the baseplate: 2 pegs and 2 pegs with an anterior spike. We compared the bone-implant micromotion under the most demanding loads from stair ascent between both designs. RESULTS: Both fixation designs had peak micromotion at the anterior-lateral edge of the baseplate. The design with 2 pegs and an anterior spike had up to 15% lower peak micromotion and up to 14% more baseplate area with micromotions below the most conservative threshold for ingrowth, 20 µm, than the design with only 2 pegs. The greatest benefit of adding an anterior spike occurred for subjects who had the smallest area of tibial bone below the 20 µm threshold (ie, most at risk for failure to achieve bone ingrowth). CONCLUSIONS: An anteriorly placed spike for cementless tibial baseplates with 2 pegs can help decrease the bone-implant micromotion during stair ascent, especially for subjects with increased bone-implant micromotion and risk for bone ingrowth failure.

6.
J Arthroplasty ; 39(6): 1518-1523, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38103805

RESUMEN

BACKGROUND: Mid-level constraint polyethylene designs provide additional stability in total knee arthroplasty (TKA). The purposes of this study were to (1) compare the survivorship and reason for revision between mid-level inserts and posterior-stabilized (PS) used in primary TKA and (2) evaluate the biomechanical constraint characteristics of mid-level inserts. METHODS: We reviewed all cases of primary TKA performed at our institution from 2016 to 2019 using either PS or mid-level constrained inserts from 1 of 6 manufacturers. Data elements included patient demographics, implants, reasons for revision, and whether a manipulation under anesthesia was performed. We performed finite element analyses to quantify the varus/valgus and axial-rotation constraint of each mid-level constrained insert. A one-to-one propensity score matching was conducted between the patients with mid-level and PS inserts to match for variables, which yielded 2 cohorts of 3,479 patients. RESULTS: For 9,163 PS and 3,511 mid-level TKAs, survivorship free from all-cause revision was estimated up to 5 years and was lower for mid-level than PS inserts (92.7 versus 94.1%, respectively, P = .004). When comparing each company's mid-level insert to the same manufacturer's PS insert, we found no differences in all-cause revision rates (P ≥ .91) or revisions for mechanical problems (P ≥ .97). Using propensity score matching between mid-level and PS groups, no significant differences were found in rates of manipulation under anesthesia (P = .72), all-cause revision (P = .12), revision for aseptic loosening (P = .07), and revision for instability (P = .45). Finite element modeling demonstrated a range in varus/valgus constraint from ±1.1 to >5°, and a range in axial-rotation constraint from ±1.5 to ±11.5° among mid-level inserts. CONCLUSIONS: Despite wide biomechanical variations in varus/valgus and axial-rotation constraint, we found minimal differences in early survivorship rates between PS and mid-level constrained knees.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Polietileno , Diseño de Prótesis , Falla de Prótesis , Reoperación , Humanos , Artroplastia de Reemplazo de Rodilla/instrumentación , Artroplastia de Reemplazo de Rodilla/métodos , Masculino , Anciano , Femenino , Reoperación/estadística & datos numéricos , Fenómenos Biomecánicos , Persona de Mediana Edad , Análisis de Elementos Finitos , Articulación de la Rodilla/cirugía , Articulación de la Rodilla/fisiopatología , Estudios Retrospectivos , Anciano de 80 o más Años
7.
Knee ; 44: 172-179, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37672908

RESUMEN

BACKGROUND: During robotic and computer-navigated primary total knee arthroplasty (TKA), the center of the femoral head is utilized as the proximal reference point for femoral component position rather than the intramedullary axis. We sought to analyze the effect on femoral component flexion-extension position between these two reference points. METHODS: We obtained CT 3D-reconstructions of 50 cadaveric intact femurs. We defined the navigation axis as the line from center of the femoral head to center of the knee (lowest point of the trochlear groove) and the intramedullary axis as the line from center of the knee to center of the canal at the isthmus. Differences between these axes in the sagittal plane were measured. Degree of femoral bow and femoral neck anteversion were correlated with the differences between the two femoral axes. RESULTS: On average, the navigated axis was 1.4° (range, -1.4° to 4.1°) posterior to the intramedullary axis. As such, the femoral component would have on average 1.4° less flexion compared with techniques referencing the intramedullary canal. A more anterior intramedullary compared with navigated axis (i.e., less femoral flexion) was associated with more femoral bow (R2 = 0.7, P < 0.001) and less femoral neck anteversion (R2 = 0.5, P < 0.05). CONCLUSION: Computer-navigated or robotic TKA in which the center of the femoral head is utilized as a reference point, results in 1.4° less femoral component flexion than would be achieved by referencing the intramedullary canal. Surgeons should be aware of these differences as they may ultimately influence knee kinematics.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Procedimientos Quirúrgicos Robotizados , Humanos , Artroplastia de Reemplazo de Rodilla/métodos , Cabeza Femoral , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Fémur/diagnóstico por imagen , Fémur/cirugía , Rango del Movimiento Articular , Computadores
8.
Knee Surg Sports Traumatol Arthrosc ; 31(11): 4842-4850, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37558747

RESUMEN

PURPOSE: The purpose of this study was to evaluate the accuracy of preoperative CT-based Anderson Orthopaedic Research Institute (AORI)-grading and to correlate Computed tomography (CT)-based volumetric defect measurements with intraoperative AORI findings. METHODS: 99 patients undergoing revision total knee arthroplasty (rTKA) with preoperative CT-images were identified in an institutional revision registry. CT-image segmentation with 3D-Slicer Software was used to create 3D tibial bone defects which were then graded according to the AORI-classification. The AORI classification categorizes tibial defects into three types: Type I has healthy cortical and cancellous bone near the joint line, Type II involves metaphyseal bone loss affecting one or both condyles, and Type III indicates deficient metaphyseal bone with distal defects and potential damage to the patellar tendon and collateral ligament attachments. These 3D-CT gradings were compared to preoperative X-ray and intraoperative AORI grading. The Friedman test was used to investigate differences between AORI values of each measurement method. Volumetric 3D-bone defect measurements were used to investigate the relationship between AORI classification and volumetric defect size in the three anatomic zones of the tibia. RESULTS: Substantial agreements between preoperative 3D-CT AORI and intraoperative AORI (kappa = 0.663; P < 0.01) and fair agreements between preoperative X-ray AORI and intraoperative AORI grading (kappa = 0.304; P < 0.01) were found. Moderate correlations between volume of remaining bone and intraoperative AORI grading were found in epiphysis (rS = - 0.529; P < 0.001), metaphysis (rS = - 0.557; P < 0.001) and diaphysis (rS = - 0.421; P < 0.001). Small volumetric differences between AORI I vs. AORI II defects and relatively large differences between AORI II and AORI III defects in each zone were detected. CONCLUSION: Tibial bone defect prediction based on preoperative 3D-CT segmentation showed a substantial agreement with intraoperative findings and is superior to standard radiograph assessment. The relatively small difference in defect volume between AORI I, IIa and IIb suggests that updated CT-based classifications might hold benefits for the planning of rTKA. LEVEL OF EVIDENCE: Retrospective Cohort Study; III.


Asunto(s)
Prótesis de la Rodilla , Tibia , Humanos , Tibia/diagnóstico por imagen , Tibia/cirugía , Estudios Retrospectivos , Artefactos , Reoperación/métodos , Tomografía Computarizada por Rayos X , Epífisis , Diseño de Prótesis , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía
9.
J Arthroplasty ; 38(4): 757-762, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36280162

RESUMEN

BACKGROUND: The tibial component in total knee arthroplasty (TKA) is often chosen to maximize coverage of the tibial cut, which can result in excessive internal rotation of the component. Optimal rotational alignment may require a smaller baseplate with suboptimal coverage that could threaten fixation. We asked: "does undersizing the tibial component of a cementless TKA to gain external rotation increase the risk of bone failure?" METHODS: We developed computational finite element (FE) analysis models from the computed tomography (CT) scans of 12 patients scheduled for primary TKA. The models were implanted with a cementless tibial baseplate that maximized coverage and one or two sizes smaller and externally rotated by 5°. We calculated the risk of bone collapse under loads representative of stair ascent. RESULTS: Undersizing the implant increased the area at risk of collapse for eight patients. However, the area at risk of collapse for the undersized implant (range, 5.2%-16.4%) was no different (P = .24) to the optimally sized implant (range, 4.5%-17.9%). The bone at risk of collapse was concentrated along the posterior edge of the implant. The area at risk of collapse was not proportional to implant size, and for four subjects undersizing the implant actually decreased the area at risk of collapse. CONCLUSION: While implants should maximize coverage of the tibial cut and seek support on dense bone, undersizing the tibial component to gain external rotation had minimal impact on the load transfer to the underlying bone. This FE analysis model of a cementless tibial baseplate may require further validation and additional studies to investigate the long-term biomechanical effects of undersizing the tibial baseplate. In conclusion, while surgeons should strive to use the appropriate tibial baseplate for each patient, our model identified only minor biomechanical consequences of undersizing the implant for the immediate postoperative bone-implant interaction and implant subsidence.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Humanos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Articulación de la Rodilla/cirugía , Análisis de Elementos Finitos , Tibia/cirugía
10.
J Arthroplasty ; 37(7S): S678-S684, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35271980

RESUMEN

BACKGROUND: Although component offset can affect impingement after total hip arthroplasty, the exact impact is unclear. Evaluation of offset on an anterior-posterior pelvic radiograph is different than evaluation in functional positions of impingement, namely flexion/internal rotation and extension/external rotation. We quantified the effect of acetabular (cup/liner) vs femoral (head/stem) offsets on changes in range of motion to extra-prosthetic impingement in these 2 impingement-prone functional positions. METHODS: We retrospectively identified 16 total hip arthroplasty patients (age 61.5 ± 12.1 years, body mass index 28.3 ± 4.9 kg/m2) with preoperative and postoperative computerized tomography scans. To eliminate metal artifact, femoral and pelvic 3-dimensional models were created using preoperative scans aligned with postoperative scans, and 3-dimensional scanned implant models were used to reproduce clinical implantation. We tested ±5 mm acetabular cup, acetabular liner, femoral stem, and femoral head offsets. Maximum range of motion (ROM) to bone-bone impingement was calculated for internal rotation at 90° flexion and external rotation at 10° extension. RESULTS: In all cases, increased offset increased ROM to impingement, and vice versa. During internal rotation at 90° flexion, ±5 mm liner offset had the greatest impact on ROM (+9°/-10°), followed by cup (+8°/-9°), head (+5°/-7°), and stem (+3°/-5°) offset. During external rotation at 10° extension, ±5 mm cup offset had the greatest impact on ROM (+10°/-10°), followed by liner (+9°/-9°), head (+7°/-8°), and stem (+4°/-4°) offset. However, no statistically significant differences were found in the changes to ROM in flexion obtained through cup and liner offsets, the changes to ROM in extension obtained through liner and head offsets, and the changes to ROM in extension obtained through increasing stem and head offsets. CONCLUSION: Increasing offset by any method reduces impingement. Center-of-rotation offset changes via acetabular cup or liner have the greatest impact on extra-prosthetic impingement.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Anciano , Artroplastia de Reemplazo de Cadera/métodos , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/cirugía , Humanos , Persona de Mediana Edad , Rango del Movimiento Articular , Estudios Retrospectivos
11.
Gac Med Mex ; 158(Monografic 1): 1-14, 2022 Jan 28.
Artículo en Español | MEDLINE | ID: mdl-35080818

RESUMEN

Although in recent years in Mexico the quality of diabetes mellitus (DM) care has improved and access to health services and medications has increased, there is a lack of adherence to the recommendations of the clinical guidelines, which could explain the poor glycemic control in many of the patients with DM. Sodium-glucose cotransporter type 2 (iSGLT2) inhibitors have been the last class of antidiabetic agents to receive approval from the Food and Drug Administration (FDA) and COFEPRIS (Mexico). In order to improve the use of SGLT2i in clinical practice in Mexico, this paper presents the recommendations issued by a panel of eleven Mexican experts based on the new published evidence for the treatment of patients with DM2.


Aunque en los últimos años en México ha mejorado la calidad de la atención de la diabetes mellitus (DM) y ha aumentado el acceso a servicios de salud y medicamentos, existe una falta de apego a las recomendaciones de las guías de práctica clínica, que podría explicar la falta de un control glucémico adecuado en muchos de los pacientes con DM. Los inhibidores del cotransportador de sodio-glucosa tipo 2 (iSGLT2) han sido la última clase de agentes antidiabéticos en recibir la aprobación de la Food and Drug Administration (FDA) y de la Comisión Federal para la Protección contra Riesgos Sanitarios de México (COFEPRIS). Con el fin de mejorar el uso de los iSGLT2 en la práctica clínica en México, en este documento se presentan las recomendaciones emitidas por un panel de 11 expertos mexicanos con base en las nuevas evidencias publicadas para el tratamiento de los pacientes con DM2.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hiperglucemia , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Consenso , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Humanos , Hipoglucemiantes/uso terapéutico
12.
J Orthop Res ; 40(4): 816-825, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34231249

RESUMEN

Component alignment in total knee arthroplasty is a determining factor for implant longevity. Mechanical alignment, which provides balanced load transfer, is the most common alignment strategy. However, a retrospective review found that varus alignment, which could lead to unbalanced loading, can happen in up to 18% of tibial baseplates. This may be particularly burdensome for cementless tibial baseplates, which require low bone-implant micromotion and avoidance of bone overload to obtain bone ingrowth. Our aim was to assess the effect of varus alignment on the bone-implant interaction of cementless baseplates. We virtually implanted 11 patients with knee OA with a modern cementless tibial baseplate in mechanical alignment and in 2° of tibial varus alignment. We performed finite element simulations throughout gait, with loading conditions derived from literature. Throughout the stance phase, varus alignment had greater micromotion and percentage of bone volume at risk of failure than mechanical alignment. At mid-stance, when the most critical conditions occurred, the average increase in peak micromotion and amount of bone at risk of failure due to varus alignment were 79% and 59%, respectively. Varus alignment also resulted in the decrease of the surface area with micromotion compatible with bone ingrowth. However, for both alignments, this surface area was larger than the average area of ingrowth reported for well-fixed implants retrieved post-mortem. Our findings suggest that small varus deviations from mechanical alignment can adversely impact the biomechanics of the bone-implant interaction for cementless tibial baseplates during gait; however, the clinical implications of such changes remain unclear.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Artroplastia de Reemplazo de Rodilla/métodos , Marcha , Humanos , Articulación de la Rodilla/cirugía , Tibia/cirugía
13.
Gac. méd. Méx ; 158(spe): 1-14, ene. 2022.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1375540

RESUMEN

Resumen Aunque en los últimos años en México ha mejorado la calidad de la atención de la diabetes mellitus (DM) y ha aumentado el acceso a servicios de salud y medicamentos, existe una falta de apego a las recomendaciones de las guías de práctica clínica, que podría explicar la falta de un control glucémico adecuado en muchos de los pacientes con DM. Los inhibidores del cotransportador de sodio-glucosa tipo 2 (iSGLT2) han sido la última clase de agentes antidiabéticos en recibir la aprobación de la Food and Drug Administration (FDA) y de la Comisión Federal para la Protección contra Riesgos Sanitarios de México (COFEPRIS). Con el fin de mejorar el uso de los iSGLT2 en la práctica clínica en México, en este documento se presentan las recomendaciones emitidas por un panel de 11 expertos mexicanos con base en las nuevas evidencias publicadas para el tratamiento de los pacientes con DM2.


Abstract Although in recent years in Mexico the quality of diabetes mellitus (DM) care has improved and access to health services and medications has increased, there is a lack of adherence to the recommendations of the clinical guidelines, which could explain the poor glycemic control in many of the patients with DM. Sodium-glucose cotransporter type 2 (iSGLT2) inhibitors have been the last class of antidiabetic agents to receive approval from the Food and Drug Administration (FDA) and COFEPRIS (Mexico). In order to improve the use of SGLT2i in clinical practice in Mexico, this paper presents the recommendations issued by a panel of eleven Mexican experts based on the new published evidence for the treatment of patients with DM2.

14.
Clin Orthop Relat Res ; 479(11): 2534-2546, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34351312

RESUMEN

BACKGROUND: Satisfactory management of bone defects is important to achieve an adequate reconstruction in revision TKA. Metaphyseal cones to address such defects in the proximal tibia are increasingly being used; however, the biomechanical superiority of cones over traditional techniques like fully cementing the implant into the defect has not yet been demonstrated. Moreover, although long stems are often used to bypass the defects, the biomechanical efficacy of long stems compared with short, cemented stems when combined with metaphyseal cones remains unclear. QUESTIONS/PURPOSES: We developed and validated finite-element models of nine cadaveric specimens to determine: (1) whether using cones for addressing moderate metaphyseal tibial defects in revision TKA reduces the risk of implant-cement debonding compared with cementing the implant alone, and (2) when using metaphyseal cones, whether long, uncemented stems (or diaphyseal-engaging stems) reduce the risk of implant-cement debonding and the cone-bone micromotions compared with short, cemented stems. METHODS: We divided nine cadaveric specimens (six male, three female, aged 57 to 73 years, BMI 24 to 47 kg/m2) with standardized tibial metaphyseal defects into three study groups: no cone with short (50-mm) cemented stem, in which the defect was filled with cement; cone with short (50-mm) cemented stem, in which a metaphyseal cone was implanted before cementing the implant; and cone with long, diaphyseal-engaging stem, which received a metaphyseal cone and the largest 150-mm stem that could fit the diaphyseal canal. The specimens were implanted and mechanically tested. Then, we developed and validated finite-element models to investigate the interaction between the implant and the bone during the demanding activity of stair ascent. We quantified the risk of implant debonding from the cement mantle by comparing the axial and shear stress at the cement-implant interface against an experimentally derived interface failure index criterion that has been previously used to quantify the risk of cement debonding. We considered the risk of debonding to be minimal when the failure index was below 10% of the strength of the interface (or failure index < 0.1). We also quantified the micromotion between the cone and the bone, as a guide to the likelihood of fixation by bone ingrowth. To this end, we assumed bone ingrowth for micromotion values below the most restrictive reported threshold for bone ingrowth, 20 µm. RESULTS: When using a short, 50-mm cemented stem and cement alone to fill the defect, 77% to 86% of the cement-implant interface had minimal risk of debonding (failure index < 0.1). When using a short, 50-mm cemented stem with a cone, 87% to 93% of the cement-implant interface had minimal debonding risk. When combining a cone with a long (150-mm) uncemented stem, 92% to 94% of the cement-implant interface had minimal debonding risk. The differences in cone-bone micromotion between short, cemented stems and long, uncemented stems were minimal and, for both configurations, most cones had micromotions below the most restrictive 20-µm threshold for ingrowth. However, the maximum micromotion between the cone and the bone was in general smaller when using a long, uncemented stem (13-23 µm) than when using a short, cemented stem (11-31 µm). CONCLUSION: Although the risk of debonding was low in all cases, metaphyseal cones help reduce the biomechanical burden on the implant-cement interface of short-stemmed implants in high-demand activities such as stair ascent. When using cones in revision TKA, long, diaphyseal-engaging stems did not provide a clear biomechanical advantage over short stems. Future studies should explore additional loading conditions, quantify the interspecimen variability, consider more critical defects, and evaluate the behavior of the reconstructive techniques under repetitive loads. CLINICAL RELEVANCE: Cones and stems are routinely used to address tibial defects in revision TKA. Despite our finding that metaphyseal cones may help reduce the risk of implant-cement debonding and allow using shorter stems with comparable biomechanical behavior to longer stems, either cones or cement alone can provide comparable results in contained metaphyseal defects. However, longer term clinical studies are needed to compare these techniques over time.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Cementos para Huesos , Interfase Hueso-Implante/fisiopatología , Prótesis de la Rodilla , Tibia/fisiopatología , Anciano , Fenómenos Biomecánicos , Cadáver , Diáfisis/fisiopatología , Diáfisis/cirugía , Femenino , Análisis de Elementos Finitos , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Reoperación , Tibia/cirugía
15.
Prim Care Diabetes ; 15(5): 887-889, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34389278

RESUMEN

There is a lack of information about the maternal-fetal outcomes in patients with gestational diabetes and concomitant COVID-19; and there is even less information about the outcomes of pregnant women with gestational diabetes and COVID-19. We present a case of a primigravidae of 20-year-old woman with gestational diabetes and COVID-19 and a review of the literature.


Asunto(s)
COVID-19 , Diabetes Gestacional , Complicaciones Infecciosas del Embarazo , Adulto , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/terapia , Femenino , Humanos , Embarazo , Resultado del Embarazo , SARS-CoV-2 , Adulto Joven
16.
Diabetol Metab Syndr ; 13(1): 42, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33836819

RESUMEN

BACKGROUND: Continuous glucose monitoring systems are increasingly being adopted as an alternative to self-monitoring of blood glucose (SMBG) by persons with diabetes mellitus receiving insulin therapy. MAIN BODY: The FreeStyle Libre flash glucose monitoring system (Abbott Diabetes Care, Witney, United Kingdom) consists of a factory-calibrated sensor worn on the back of the arm which measures glucose levels in the interstitial fluid every minute and stores the reading automatically every 15 min. Swiping the reader device over the sensor retrieves stored data and displays current interstitial glucose levels, a glucose trend arrow, and a graph of glucose readings over the preceding 8 h. In patients with type 2 diabetes (T2D) receiving insulin therapy, pivotal efficacy data were provided by the 6-month REPLACE randomized controlled trial (RCT) and 6-month extension study. Compared to SMBG, the flash system significantly reduced the time spent in hypoglycemia and frequency of hypoglycemic events, although no significant change was observed in glycosylated hemoglobin (HbA1c) levels. Subsequent RCTs and real-world chart review studies have since shown that flash glucose monitoring significantly reduces HbA1c from baseline. Real-world studies in both type 1 diabetes or T2D populations also showed that flash glucose monitoring improved glycemic control. Higher (versus lower) scanning frequency was associated with significantly greater reductions in HbA1c and significant improvements in other measures such as time spent in hypoglycemia, time spent in hyperglycemia, and time in range. Additional benefits associated with flash glucose monitoring versus SMBG include reductions in acute diabetes events, all-cause hospitalizations and hospitalized ketoacidosis episodes; improved well-being and decreased disease burden; and greater treatment satisfaction. CONCLUSION: T2D patients who use flash glucose monitoring might expect to achieve significant improvement in HbA1c and glycemic parameters and several associated benefits.

17.
J Orthop Res ; 39(1): 94-102, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33146417

RESUMEN

In total ankle arthroplasty, the interaction at the joint between implant and bone is driven by a complex loading environment. Unfortunately, little is known about the loads at the ankle during daily activities since earlier attempts use two- or three-dimensional models to explore simplified joint mechanics. Our goal was to develop a framework to calculate multi-axial loads at the joint during simulated level walking following total ankle arthroplasty. To accomplish this, we combined robotic simulations of level walking at one-quarter bodyweight in three cadaveric foot and ankle specimens with musculoskeletal modeling to calculate the multi-axial forces and moments at the ankle during the stance phase. The peak compressive forces calculated were between 720 and 873 N occurring around 77%-80% of stance. The peak moment, which was the internal moment for all specimens, was between 6.1 and 11.6 N m and occurred between 72% and 88% of the stance phase. The peak moment did not necessarily occur with the peak force. The ankle joint loads calculated in this study correspond well to previous attempts in the literature; however, our robotic simulator and framework provide an opportunity to resolve the resultant three-dimensional forces and moments as others have not in previous studies. The framework may be useful to calculate ankle joint loads in cadaveric specimens as the first step in evaluating bone-implant interactions in total ankle replacement using specimen specific inputs. This approach also provides a unique opportunity to evaluate changes in joint loads and kinematics following surgical interventions of the foot and ankle.


Asunto(s)
Articulación del Tobillo/fisiología , Artroplastia de Reemplazo de Tobillo , Análisis de Elementos Finitos , Modelos Biológicos , Caminata/fisiología , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Soporte de Peso
18.
J Orthop Res ; 39(1): 103-111, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33030768

RESUMEN

Finite element (FE) models to evaluate the burden placed on the interaction between total ankle arthroplasty (TAA) implants and the bone often rely on peak axial forces. However, the loading environment of the ankle is complex, and it is unclear whether peak axial forces represent a challenging scenario for the interaction between the implant and the bone. Our goal was to determine how the loads and the design of the fixation of the tibial component of TAA impact the interaction between the implant and the bone. To this end, we developed a framework that integrated robotic cadaveric simulations to determine the ankle kinematics, musculoskeletal models to determine the ankle joint loads, and FE models to evaluate the interaction between TAA and the bone. We compared the bone-implant micromotion and the risk of bone failure of three common fixation designs for the tibial component of TAA: spikes, a stem, and a keel. We found that the most critical conditions for the interaction between the implant and the bone were dependent on the specimen and the fixation design, but always involved submaximal forces and large moments. We also found that while the fixation design influenced the distribution and the peak value of bone-implant micromotion, the amount of bone at risk of failure was specimen dependent. To account for the most critical conditions for the interaction between the implant and the bone, our results support simulating multiple specimens under complex loading profiles that include multiaxial moments and span entire activity cycles.


Asunto(s)
Articulación del Tobillo/fisiología , Artroplastia de Reemplazo de Tobillo , Interfase Hueso-Implante/fisiología , Tibia/cirugía , Caminata/fisiología , Fenómenos Biomecánicos , Femenino , Análisis de Elementos Finitos , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , Soporte de Peso
19.
PLoS One ; 15(11): e0242889, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33253280

RESUMEN

All 4 dengue viruses (DENV) cause sporadic outbreaks of human disease in the Rio Grande Valley along the US-Mexico border. In addition, West Nile virus (WNV) is enzootic in most border communities, and is the only arbovirus known to cause human disease in the El Paso, Texas community. In an effort to determine if DENV were also endemic in the El Paso community, a serosurvey was conducted among mothers at the time of delivery of their babies in selected hospitals. Cord-blood plasma samples obtained from mothers were tested for DENV antibody by an enzyme-linked immuno-sorbent assay (ELISA), plaque reduction neutralization test (PRNT) and a multiplex microsphere immunoassay. All DENV antibody positive plasma samples were also tested for WNV antibody by the same assays to consider the possibility that DENV antibody positive samples reflected WNV cross reactive antibody. The results indicated that 0.74% (11/1,472) of the mothers had a previous DENV infection and that 3.3% (48/1,472) had a previous WNV infection. Of these mothers, 0.20% (3/1,472) had antibody to both DENV and WNV as evidence of infection by both viruses. The results indicated that 0.2% (3/1472) of the mothers were positive for antibody to only WNV envelope, thus suggesting an undetermined flavivirus infection. Although 6 of the 11 DENV antibody positive mothers did not have a history of travel to a DENV endemic country, the findings of this survey provided further evidence of local transmission of WNV and suggested the possibility of focal autochthonous transmission of DENV in the El Paso community.


Asunto(s)
Anticuerpos Antivirales/sangre , Virus del Dengue/patogenicidad , Dengue/sangre , Virus del Nilo Occidental/patogenicidad , Dengue/epidemiología , Dengue/virología , Virus del Dengue/genética , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Humanos , Inmunoglobulina G/sangre , México/epidemiología , Embarazo , Mujeres Embarazadas , Pruebas Serológicas , Texas/epidemiología , Virus del Nilo Occidental/genética
20.
Diabetes Obes Metab ; 21(8): 1967-1972, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31124299

RESUMEN

In this post hoc analysis of the randomized controlled LixiLan-O trial in insulin-naive patients with type 2 diabetes mellitus (T2DM) not controlled with metformin, with or without a second oral antihyperglycaemic drug (OAD), the efficacy and safety of the fixed-ratio combination, iGlarLixi (insulin glargine 100 U [iGlar] and lixisenatide [Lixi]), compared to its individual components was assessed in two patient subgroups: group 1) baseline HbA1c ≥9% (n = 134); group 2) inadequate control (HbA1c ≥7.0% and ≤9.0%) despite administration of two OADs at screening (n = 725). Treatment with iGlarLixi resulted in significantly greater reduction in least squares mean HbA1c compared to treatment with iGlar or Lixi alone in both subgroups (group 1: 2.9%, 2.5%, 1.7% and group 2: 1.5%, 1.2%, 0.7%, respectively). Target HbA1c less than 7% was achieved in more than 70% of patients using iGlarLixi in both subgroups, while mitigating the weight gain observed with use of iGlar alone. Rates of hypoglycaemic events were low overall. These results suggest that treatment with iGlarLixi achieves superior glycaemic control compared to treatment with iGlar or Lixi alone in T2DM patients with HbA1c ≥9% or in those inadequately controlled with two OADs.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hemoglobina Glucada/efectos de los fármacos , Hipoglucemiantes/administración & dosificación , Insulina Glargina/administración & dosificación , Péptidos/administración & dosificación , Adulto , Glucemia/efectos de los fármacos , Diabetes Mellitus Tipo 2/sangre , Quimioterapia Combinada , Femenino , Humanos , Hipoglucemia/inducido químicamente , Hipoglucemia/epidemiología , Análisis de los Mínimos Cuadrados , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Aumento de Peso/efectos de los fármacos
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