Estabilización de fracturas Schatzker I de la meseta tibial. Estudio numérico comparativo mediante elementos finitos. Placas bloqueadas vs tornillos canulados

ResumenObjetivoLa estabilización quirúrgica de las fracturas SchatzkerI de meseta tibial se realiza principalmente mediante la colocación de tornillos canulados o mediante la aplicación de una placa con tornillos bloqueados proximales. En el postoperatorio, los pacientes realizan generalmente una descarga de 6 u 8 semanas. Usando el método de elementos finitos (EF), este estudio intenta analizar si la carga inmediata del paciente después de la cirugía genera un exceso de desplazamiento interfragmentario (DI).MétodosUtilizando un modelo validado de EF de paciente sano, el modelo tibial se reprodujo geométricamente, y se realizó una fractura SchatzkerI tipo a partir de radiografías y TAC de diferentes pacientes. Se modelizaron tornillos canulados de 6,5mm y una placa Polyax (Biomet Inc, EE.UU.), implantándose virtualmente en la tibia fracturada, y aplicando una fuerza de 400N, equivalente a 80kg de peso del paciente en bipedestación. Los DI se calcularon a partir del desplazamientos de diferentes nodos en el área fractuaria.ResultadosLos DI máximos calculados con la placa Polyax y los tornillos canulados fueron de 0,1-0,15mm y 0,25-0,3mm, respectivamente. Sin embargo, aplicando un peso de un 20% existía riesgo de fractura por compresión con los tornillos canulados. Con la placa Polyax se obtuvo una mejor distribución de las cargas, manteniéndose en zona segura por debajo de 100Mpa con la aplicación del 50% del peso del paciente.ConclusiónEste estudio sugiere que ambos sistemas tienen un resultado similar en cuanto al DI, pero la placa realiza una mejor distribución de las cargas en la zona de la fractura, permitiendo la carga parcial inmediata de un 50% del peso del paciente.AbstractObjectiveSurgical stabilization of split fractures of the lateral tibial plateau may involve percutaneous insertion of cannulated screws or more invasive implantation of locked plating systems. In any case, six to eight weeks of non-weight-bearing are recommended. By using the finite element (FE) method, this study aimed to assess whether immediate weight bearing can generate excessive interfragmentary motions (IM).MethodsA validated femur-tibia FE model of a healthy patient was used. The tibia model was reconverted into geometry, and a SchatzkerI fracture was re-created based on patient x-rays. Cannulated 6.5mm cancellous bone screws, and a Polyax tibial locked plating system (Biomet Inc, USA) were modelled, and virtually implanted into the fractured tibia geometry. An axial force of 400N pressed the femur model against the tibial plateau, simulating the weight of an 80Kg patient in bipedal stance. IM were calculated as the displacements between two nodes initially superimposed in the fracture areaResultsMaximum IM calculated with the Polyax and with the cannulated screw fixations were around 0.1-0.15mm, and 0.25-0.3mm, respectively. Both systems led to similar IM up to 80-90% of applied body weight. However, applying over 20% of the simulated body weight might lead to a risk of compression bone fracture. With the Polyax system, bone stresses were better distributed, and remained below 100MPa at 30% of body weight. Maximum stresses in the implants were about half the reported strength for the alloy simulated.ConclusionThis study suggested that IM caused by weight bearing might not impede bone healing in a fracture stabilized with either a Polyax locked plating system or cannulated screws. However, cannulated screw systems could lead to harmful load concentrations in the bone with immediate weight bearing. Plate systems will allow around 50% of immediate weight bearing

20-Year Risks of Breast-Cancer Recurrence after Stopping Endocrine Therapy at 5 Years

The administration of endocrine therapy for 5 years substantially reduces recurrence rates during and after treatment in women with early-stage, estrogen-receptor (ER)-positive breast cancer. Extending such therapy beyond 5 years offers further protection but has additional side effects. Obtaining data on the absolute risk of subsequent distant recurrence if therapy stops at 5 years could help determine whether to extend treatment

Effectiveness of the Intratissue Percutaneous Electrolysis (EPI®) technique and isoinertial eccentric exercise in the treatment of patellar tendinopathy at two years follow-up

Aim: to show the effect of Intratissue Percutaneous Electrolysis (EPI®) combined with eccentric programme in the treatment of patellar tendinopathy. Methods: prospective study of 33 athlete-patients consecutively treated for insertional tendinopathy with Intratissue Percutaneous Electrolysis (EPI®) and followed for 2 years. Functional assessment was performed at the first visit, at three months and two years with the Tegner scale and VISA-P. Results: an average improvement in the VISA-P of 35 points was obtained. The mean duration of treatment was 4.5 weeks. Some 78.8% of the patients returned to the same level of physical activity as before the injury by the end of treatment, reaching 100% at two years. Conclusions: intratissue percutaneous electrolysis (EPI®) combined with an eccentric-based rehab program offers excellent results in terms of the clinical and functional improvement of the patellar tendon with low morbidity in a short-term period. Level of Evidence: Therapy, level 4

Posterolateral corner of the knee: an expert consensus statement on diagnosis, classification, treatment, and rehabilitation

© 2018, European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA). Purpose: To develop a statement on the diagnosis, classification, treatment, and rehabilitation concepts of posterolateral corner (PLC) injuries of the knee using a modified Delphi technique. Methods: A working group of three individuals generated a list of statements relating to the diagnosis, classification, treatment, and rehabilitation of PLC injuries to form the basis of an initial survey for rating by an international group of experts. The PLC expert group (composed of 27 experts throughout the world) was surveyed on three occasions to establish consensus on the inclusion/exclusion of each item. In addition to rating agreement, experts were invited to propose further items for inclusion or to suggest modifications of existing items at each round. Pre-defined criteria were used to refine item lists after each survey. Statements reaching consensus in round three were included within the final consensus document. Results: Twenty-seven experts (100% response rate) completed three rounds of surveys. After three rounds, 29 items achieved consensus with over 75% agreement and less than 5% disagreement. Consensus was reached in 92% of the statements relating to diagnosis of PLC injuries, 100% relating to classification, 70% relating to treatment and in 88% of items relating to rehabilitation statements, with an overall consensus of 81%. Conclusions: This study has established a consensus statement relating to the diagnosis, classification, treatment, and rehabilitation of PLC injuries. Further research is needed to develop updated classification systems, and better understand the role of non-invasive and minimally invasive approaches along with standardized rehabilitation protocols. Level of evidence: Consensus of expert opinion, Level V

Capsular fixation limits graft extrusion in lateral meniscal allograft transplantation

Purpose: The main purpose of this investigation was to compare the amount of graft extrusion of lateral meniscal allograft transplantation (MAT) performed with a suture-only technique with or without a capsulodesis. Secondarily, the assessment of functional results was also covered. We hypothesized that capsular fixation reduces the post-operative degree of allograft extrusion and it does not affect the functional outcomes during the short-term follow-up period studied. Methods: Prospective series of 29 lateral MAT. Fifteen were fixed with a suture-only technique (group A). The remaining 14 cases (group B) also included arthroscopic lateral capsular fixation (capsulodesis). Functional results were assessed with Lysholm, Tegner, and VAS for pain. Magnetic resonance imaging (MRI) was performed to determine the degree of meniscal extrusion. Millimeters of extrusion and percentage of extruded meniscal tissue were calculated for both groups. The degree of extrusion was considered minor if it was 3 mm. Results: Group A had 11 cases (73.3%) of major extrusion and group B had 4 cases (28.6%) (p = 0.02). The percentage of extruded meniscal tissue was 35% in group A and 24.6% in group B (p = 0.04). At a mean 3.4 years (range 1-4) post-operatively, the Lysholm score had a mean 89.60 ± 6.93 and 91.43 ± 6.19 points in groups A and B, respectively (p < 0.001). The median follow-up Tegner score improved from 4 (range 3-5) to 7 (range 6-9) in group A (p < 0.001) and from 4 (range 3-5) to 7 (range 6-8) in group B (p < 0.001). VAS dropped 5 and 7.3 points in groups A and B, respectively (p < 0.001). There were no complications in this series. Conclusions: In lateral MAT with the suture-only fixation technique, the described capsulodesis minimized meniscal extrusion. In terms of functional results, there were no differences between the groups at a mean 3.4-year follow-up

Long-term outcomes for neoadjuvant versus adjuvant chemotherapy in early breast cancer : meta-analysis of individual patient data from ten randomised trials

Background Neoadjuvant chemotherapy (NACT) for early breast cancer can make breast-conserving surgery more feasible and might be more likely to eradicate micrometastatic disease than might the same chemotherapy given after surgery. We investigated the long-term benefits and risks of NACT and the influence of tumour characteristics on outcome with a collaborative meta-analysis of individual patient data from relevant randomised trials. Methods We obtained information about prerandomisation tumour characteristics, clinical tumour response, surgery, recurrence, and mortality for 4756 women in ten randomised trials in early breast cancer that began before 2005 and compared NACT with the same chemotherapy given postoperatively. Primary outcomes were tumour response, extent of local therapy, local and distant recurrence, breast cancer death, and overall mortality. Analyses by intention-to-treat used standard regression (for response and frequency of breast-conserving therapy) and log-rank methods (for recurrence and mortality). Findings Patients entered the trials from 1983 to 2002 and median follow-up was 9 years (IQR 5-14), with the last follow-up in 2013. Most chemotherapy was anthracycline based (3838 [81%] of 4756 women). More than two thirds (1349 [69%] of 1947) of women allocated NACT had a complete or partial clinical response. Patients allocated NACT had an increased frequency of breast-conserving therapy (1504 [65%] of 2320 treated with NACT vs 1135 [49%] of 2318 treated with adjuvant chemotherapy). NACT was associated with more frequent local recurrence than was adjuvant chemotherapy: the 15 year local recurrence was 21.4% for NACT versus 15.9% for adjuvant chemotherapy (5.5% increase [95% CI 2.4-8.6]; rate ratio 1.37 [95% CI 1.17-1.61]; p = 0.0001). No significant difference between NACT and adjuvant chemotherapy was noted for distant recurrence (15 year risk 38.2% for NACT vs 38.0% for adjuvant chemotherapy; rate ratio 1.02 [95% CI 0.92-1.14]; p = 0.66), breast cancer mortality (34.4% vs 33.7%; 1.06 [0.95-1.18]; p = 0.31), or death from any cause (40.9% vs 41.2%; 1.04 [0.94-1.15]; p = 0.45). Interpretation Tumours downsized by NACT might have higher local recurrence after breast-conserving therapy than might tumours of the same dimensions in women who have not received NACT. Strategies to mitigate the increased local recurrence after breast-conserving therapy in tumours downsized by NACT should be considered-eg, careful tumour localisation, detailed pathological assessment, and appropriate radiotherapy. Copyright (c) The Author(s). Published by Elsevier Ltd.Peer reviewe