Standard versus customised locking plates for fixation of schatzker ii tibial plateau fractures

Aim3D-printed implants could improve the capture of fracture fragments for improved stability of tibial plateau fracture fixation. The aim of this study was to compare the biomechanical strength of fixation constructs using standard and customised 3D-printed proximal tibial locking plates for fixation of tibial plateau fractures.MethodsThis is a biomechanical study utilising six pairs of cadaveric tibiae. Fractures were created in an identical fashion using an osteotome and mallet, and fixed using either a standard, commercially-available proximal tibia locking plate or a customised 3D-printed plate. Design and production of the customised plates followed a “3D printing at point-of-care” model. Customised stainless steel 316 L plates were produced within a local additive manufacturing laboratory based upon pre-operative CT scans. Determination of implant choice within each cadaver pair was performed via simple randomisation. Following fracture fixation, the tibiae were skeletalised and biomechanically tested using a customised loading jig and a size-matched femoral knee prosthesis. The constructs were loaded cyclically from 100 N to approximately three times the cadaveric body-weight at 5 Hz for 10 000 cycles. Every 1000 cycles, the test was paused and the tibia was physically checked for failure. If failure had not occurred by the end of the testing cycle, the construct was loaded to failure and the load at which the construct failed was noted.ResultsFixation constructs using the 3D-printed plates performed comparably to those using the standard plates. There was no significant difference in the degree of fracture fragment displacement in both constructs. Overall longitudinal construct stiffness and load to failure was higher in the 3D-plates group but this did not reach statistical significance.ConclusionProduction of customised plates for proximal tibia fractures at point-of-care is feasible, however fixation constructs with these plates did not provide any biomechanical advantage over standard plates in terms of axial loading stiffness.     

Three-dimensional finite element analysis of intramedullary nail with different materials in the treatment of intertrochanteric fractures

Intramedullary nails are the common treatment options for femoral intertrochanteric fractures. However, aseptic loosening is considered to be one of the primary forms of failure that can be caused by the stress shielding between the bone and implants. The matching in mechanical properties of implant and bone is a key issue to prevent this failure. Polyetheretherketone (PEEK) and Function-graded (FG) materials are widely used in clinical because of their excellent mechanical properties. In this study, to investigate the biomechanical behaviors of intramedullary nails made of Ti-6Al-4V alloy, Stainless Steel (SS), PEEK and two FG materials, three-dimensional finite element models of intertrochanteric fracture femur with intramedullary nail were constructed with ABAQUS. The maximum von Mises stress on the femoral fracture surface fixed by PEEK intramedullary nail was the largest, followed by FG intramedullary nail, which help stimulate bone growth and subsequently reduce fracture healing time. Compared with traditional metal intramedullary nails, PEEK and FG implants might increase von Mises stress along the same path in the proximal femur. The results showed that PEEK and FG intramedullary nails obviously changed the stress distributions in the bone and reduced stress shielding. This finding indicated that PEEK and FG intramedullary nails have the potential to become alternatives to the conventional metal intramedullary nails.     

Effect of Dexmedetomidine infusion during hip fracture surgery on hemodynamic parameters and blood loss: A triple-blinded Randomized Clinical Trial

Introduction In this study, we aim to assess the intra-operative effect of dexmedetomidine administration on the hemodynamic parameters and bleeding volume during hip fracture surgery.Patients and methods we designed and implemented a triple-blinded randomized clinical trial to objectively compare the effects of 0.5 µg/kg/h infusion of dexmedetomidine with placebo (equal amount of normal saline) during hip fracture surgery. All included cases were between 30 and 70 years old and underwent surgery for fixation of a proximal femur fracture from September 26, 2020 until February 15, 2021. They were all ASA class I or II with preoperative hemoglobin levels of 10 mg/dL or higher. Surgical blood loss and hemodynamic parameters were documented.Results 76 patients were enrolled. There were no significant differences in baseline patient characteristics. The bleeding rate was 620 ± 190.0 mL for the normal saline group and 476 ± 177.98 mL in the dexmedetomidine group (P = 0.04). No significant effect on hemodynamic parameters was observed.Conclusion Based on the current study, intravenous infusion of dexmedetomidine during hip fracture surgery under general anesthesia reduced the amount of intraoperative bleeding without causing any significant hemodynamic disturbances.Registration number IRCT20191222045857N1 (Iranian Registry of Clinical Trials)     

胫骨干骨折带锁髓内钉固定和钢板螺钉固定的对比研究

目的：对照回顾性分析带锁髓内钉和钢板内固定两种方法治疗胫骨干骨折的效果。方法：髓内钉组32例（35处骨折）,根据AO分型,42A型11处,42B型18处,42C型6处;钢板组42例（45处骨折）,42A型10处,42B型22处,42C型13处。平均伤后手术时间在髓内钉和钢板组分别为3d和3.5d。随访评估患者手术时间,活动度,愈合时间,术后并发症之间的差别。结果：术后平均随访13个月（8～26个月）。髓内钉组平均手术时间为84min,钢板螺钉组平均为93min。髓内钉组踝关节平均背屈度为13°（0°～20°）,钢板组为11°（0°～20°）;跖屈分别为41°（30°～50°）,47°（30°～50°）。愈合时间髓内钉组平均为3.3个月,钢板螺钉平均为3.5个月。术后X线片显示髓内钉固定有1例出现旋转畸形,钢板组有3例出现成角畸形,均为胫骨远端1/3骨折。结论：在治疗胫骨骨折方面,带锁髓内钉和钢板内固定两种方法都可以取得理想的效果。     

保留胫骨止点的腘绳肌腱移植重建膝交叉韧带

目的 研究保留胫骨止点的自体腘绳肌肌腱移植重建交叉韧带的优缺点。方法 自2001年7月至2005年3月间我院收治交叉韧带断裂患者33例，前交叉韧带断裂17例，后交叉韧带断裂10例，前后交叉韧带断裂并外侧副韧带断裂3例，前后交叉韧带并内侧副韧带断裂3例。其中男性28例，女性5例。平均年龄28．2岁（18-45岁）。平均随访时间3．9年（范围0．5～5年）。使用特制取腱器将半腱肌腱和股薄肌腱从肌腹中抽出，回折锁边缝合成四股，穿过胫骨和股骨隧道。远端经过骨孔以界面钉固定或经过骨桥固定。结果 按照JOA膝关节韧带损伤疗效判定标准，手术前后评分分别为46．0分和79．8分，Lysholm膝关节评分标准手术前后分别为54．4分和80．3分（P〈0．001）。胫骨前移：术前平均10．9mm（范围9～13mm），术后平均3．6mm（范围0～7mm）（P〈0．001）。结论 保留胫骨止点的腘绳肌肌腱移植，可以适用于前后交叉韧带重建，其优点是取材方便，并发症少，胫骨隧道不再需要内固定。     

The impact of trauma on neutrophil function

A well described consequence of traumatic injury is immune dysregulation, where an initial increase in immune activity is followed by a period of immune depression, the latter leaving hospitalised trauma patients at an increased risk of nosocomial infections. Here, we discuss the emerging role of the neutrophil, the most abundant leucocyte in human circulation and the first line of defence against microbial challenge, in the initiation and propagation of the inflammatory response to trauma. We review the findings of the most recent studies to have investigated the impact of trauma on neutrophil function and discuss how alterations in neutrophil biology are being investigated as potential biomarkers by which to predict the outcome of hospitalised trauma patients. Furthermore, with trauma-induced changes in neutrophil biology linked to the development of such post-traumatic complications as multiple organ failure and acute respiratory distress syndrome, we highlight an area of research within the field of trauma immunology that is gaining considerable interest: the manipulation of neutrophil function as a means by which to potentially improve patient outcome.     

Semaphoring 3A: An association between traumatic brain injury and enhanced osteogenesis

An accelerated speed of fracture-healing in patients with traumatic brain injury (TBI) is often encountered in clinical practice. However the mechanisms responsible for this phenomenon are remain unclear. After TBI, many cytokines have been reported change their expressions, suggest that the phenomenon of accelerated speed of fracture-healing may be associated with these cytokines. Semaphorin 3A is a secreted cytokine regulated by neural injury, and it is known to guide axon/dendrite growth and neuronal migration. Recent studies suggest that Semaphorin 3A is so far the only molecule that can regulate bone resorption and formation synchronously. However, a Semaphoring 3A which could perhaps induce enhanced osteogenesis under TBI condition has not yet been identified. Therefore, we presume that Semaphoring 3A may play a key role in accelerated fracture-healing under TBI condition, and these will make Sema3A as a promising potential therapeutic target for facilitating fracture healing.     

组配式生物型股骨柄在复杂髋翻修中的应用

目的 :探讨组配式生物型股骨柄MP假体应用于复杂髋翻修的手术技术要点及疗效。方法 :回顾性分析2002年1月至2013年12月行MP假体翻修的患者,共246例获得随访,男148例,女98例;年龄26~83岁,平均62.5岁。术后随访0.5~11年,平均5.7年。翻修原因:无菌松动107例,髋关节置换术后感染104例,其他35例有不明原因疼痛、假体周围骨折、磨损及脱位等。根据Paprosky分型,股骨骨缺损Ⅰ型14例,Ⅱ型39例,ⅢA型171例,ⅢB型22例。术前髋关节Harris评分37.4±7.5。随访患者行影像学检查、临床疗效评估及主观满意度调查。结果:随访时Harris评分提升至87.8±4.2,高于术前(t=92.13,P=0.00)。双下肢长度、术后稳定性及患者总体主观满意度结果:非常满意分别为27、60及61例。最常见的并发症为骨折29例,其中术中21例,术后8例;其他并发症包括感染7例,脱位5例,坐骨神经不全损伤所致患肢麻木6例、肿胀3例。随访X线显示4例假体下沉(>1 cm),其中2例翻修。结论:MP假体用于复杂髋翻修(尤其是股骨近端严重骨缺损)患者,远、近期随访效果良好,且用于感染翻修成功率高。为避免并发症,提高手术效果,术中需要仔细操作,掌握适应证及手术技术要点。