Mixed Reality Combined with Three‐Dimensional Printing Technology in Total Hip Arthroplasty: An Updated Review with a Preliminary Case Presentation

Three‐dimensional (3D) printing technology, virtual reality, and augmented reality technology have been used to help surgeons to complete complex total hip arthroplasty, while their respective shortcomings limit their further application. With the development of technology, mixed reality (MR) technology has been applied to improve the success rate of complicated hip arthroplasty because of its unique advantages. We presented a case of a 59‐year‐old man with an intertrochanteric fracture in the left femur, who had received a prior left hip fusion. After admission to our hospital, a left total hip arthroplasty was performed on the patient using a combination of MR technology and 3D printing technology. Before surgery, 3D reconstruction of a certain bony landmark exposed in the surgical area was first performed. Then a veneer part was designed according to the bony landmark and connected to a reference registration landmark outside the body through a connecting rod. After that, the series of parts were made into a holistic reference registration instrument using 3D printing technology, and the patient's data for bone and surrounding tissue, along with digital 3D information of the reference registration instrument, were imported into the head‐mounted display (HMD). During the operation, the disinfected reference registration instrument was installed on the selected bony landmark, and then the automatic real‐time registration was realized by HMD through recognizing the registration landmark on the reference registration instrument, whereby the patient's virtual bone and other anatomical structures were quickly and accurately superimposed on the real body of the patient. To the best of our knowledge, this is the first report to use MR combined with 3D printing technology in total hip arthroplasty.     

Customized three-dimensionally printed mandibular external fixator

The advent of customized three-dimensional (3D) printing allows the affordable manufacturing of sophisticated medical devices, thereby providing swift and simple solutions to specific needs in modern healthcare. Meanwhile, certain devices such as industrial mandibular external fixators (EFs) have become less and less available from medical device companies because of decreased indications. What is more, their handling is often complex. The authors report, step by step, the original design and uneventful clinical use of a 3D-printed, customized mandibular EF. This device was designed together with a positioning and drilling guide for the fixation of a septic mandibular pseudarthrosis. It provided an adequate and satisfactory balance between lightness and rigidity. A simple, accurate and safe placement of the EF was achieved thanks to the skin-supported positioner and drilling guide, thereby making the procedure minimally invasive and time-efficient. To our knowledge, this is the first reported clinical use of a 3D-printed, customized mandibular EF to date. Because such 3D technology is becoming increasingly available to a large number of surgeons, the authors believe that the present innovation could become an alternative to reusable standard EFs.     

3D打印制备不同重量比例的n-HA/PLA/PVA复合膜性能比较

目的:通过3D打印的方法制备的不同重量比例的纳米羟基磷灰石/聚乳酸/聚乙烯醇(n-HA/PLA/PVA)复合膜,并对其相关性能检测。方法:采用3D打印技术制备不同重量比例的n-HA/PLA/PVA复合膜,分别为PLA/PVA复合膜、15%n-HA/PLA/PVA复合膜、50%n-HA/PLA/PVA复合膜、75%n-HA/PLA/PVA复合膜。扫描电镜下观察各组膜形态,对其力学性能、细胞毒性及动物实验相应指标进行检测。结果:扫描电镜下观察,n-HA/PLA/PVA复合膜呈现三维网状结构,各材料间相互结合,孔隙分布不均,大小不一。随着n-HA质量浓度的提高,电镜下见各材料间孔隙逐渐减小,形成结构均匀的复合膜。力学性能及吸水率检测中,随着nHA含量的增加,n-HA/PLA/PVA复合膜的拉伸强度及吸水率呈下降趋势;细胞毒性检测,不同比例复合膜的细胞增殖率无明显差别,无细胞毒性。动物实验测量牙周菌斑指数及龈沟出血指数未发现不同比例n-HA/PLA/PVA复合膜有统计学差异。结论:3D打印不同比例的n-HA/PLA/PVA复合膜具有良好的物理性能和细胞生物相容性,n-HA比例更高的复合膜可能具有更好的物理性能及良好的生物相容性。     

金属基3D打印支架的构建与功能化研究进展

金属基3D打印支架是用来治疗骨缺损的重要方式。随着科学技术的发展，近年来金属基3D打印支架开始演变出各种功能，主要包括抗菌、载药与药物控释及诱导成骨。为了使金属支架达到不同的功能，需要特定的构建工艺与方式，如改进拓扑结构、微弧氧化、纳米修饰、表面涂层等。本文就目前金属基3D打印支架的构建与功能化在骨科的研究进展做出综述。     

Involvement of the open-source community in combating the worldwide COVID-19 pandemic: a review

Abstract

The ongoing COVID-19 pandemic is unprecedented in the modern age both due to its scale and its disruption to daily life throughout the world. Widespread social isolation and restrictions in the age of modern communicative technology, coupled with some early successes for makers, have united the open-source community towards a common goal in a way not previously seen. Local hospitals and care facilities are turning to makers to print essential consumable parts, such as simple visors, while in the hardest hit areas, critical pieces of medical technology are being fabricated. While important and effective innovations are appearing almost daily, there are also some worrying trends towards hobbyists attempting manufacture of complex medical devices with little understanding of the clinical or scientific rationale behind their design. The nature of the open-source community, an area of intensive innovation, fluidity, and experimentation, jars with the exacting standards of medical device regulation. Here, we review the involvement of rapid prototyping and the open-source community in the key areas of personal protective equipment (PPE), diagnostics, critical care technology, and information acquisition and sharing, highlighting where makers and hackers have clashed with medical device regulations, and areas where the system has worked well to facilitate change.     

健骨益肾汤促进个性化3D打印脊柱CLIF术后恢复的临床研究

目的：研究健骨益肾汤对个性化3D打印脊柱微创猫眼侧方腰椎融合术（CLIF）术后恢复的影响。方法：选取2019年1月至2020年1月在河南省洛阳正骨医院接受CLIF术治疗的50例腰椎退行性侧弯患者,将其中单纯手术治疗的24例患者纳入对照组,将其中于CLIF术后应用健骨益肾汤治疗的26例患者纳入观察组。比较两组患者临床指标、临床症状评分,术前、术后2周、术后1个月及预后（术后1年）观察两组患者的腰椎Oswestry功能障碍指数问卷表（ODI）评分的变化情况,术后1年的矫正效果。结果：观察组患者术后引流量少于对照组,差异具有统计学意义（P <0.05）;观察组患者术后下肢麻木、腰部疼痛、步行障碍、感觉障碍评分均低于对照组,差异具有统计学意义（P <0.05）;术后2周、术后1个月,观察组患者ODI评分均低于对照组,差异具有统计学意义（P <0.05）;两组患者预后侧凸Cobb角度、骨盆倾斜角度、腰椎前凸角度、矢状面轴向距离、冠状面平衡均低于术前,差异具有统计学意义（P <0.05）,两组患者术前、预后各项指标组间比较,差异无统计学意义（P> 0.05）。结论：健...     

3D打印技术在脊柱侧凸矫形中的应用效果分析

目的探讨3D打印技术在脊柱侧凸矫形中的应用效果。方法 76例脊柱侧凸患者随机分为两组各38例。两组均实施后路小切口微创分期术,对照组行常规CT或X线辅助手术治疗,观察组行术前3D打印技术辅助手术治疗。比较两组的手术效果以及并发症。结果观察组的置钉准确率高于对照组,平均置钉时间短于对照组(P <0.05)。术后,观察组的终末融合后侧凸主侧凸冠状位Cobb角低于对照组,初次平均矫正率高于对照组(P <0.05)。两组的并发症发生率无统计学差异(P>0.05)。结论术前应用3D打印技术辅助治疗脊柱侧凸,可有效提升手术效果,更好地恢复脊柱生理弯曲,提高矫形成功率。     

Pediatric cranial osteoblastoma: Technical note of surgical treatment and review of the literature

Osteoblastoma of the skull is a rare entity, and they account only for 2-4% of all the cases of osteoblastoma. We perform a comprehensive review of the pertinent literature on the subject and we report a case of a 3-year-old girl presenting with a 6-month history of a supraorbital mass and exophthalmos due to an osteoblastoma of the frontal and ethmoid bones involving the orbit and anterior skull base. A 3D printed model of the patient's skull was used for the preoperative planning and reconstruction strategy. Total en-bloc resection of the tumor followed by immediate reconstruction was achieved. No recurrence was detected 3 years after the surgery. Gross total resection is strongly advised with skull osteoblastoma, especially in young age, because of the risk of the recurrence and malignant transformation. 3D printing is proven to be a valuable tool to enhance surgical performance by avoiding complications while achieving total resection with accurate reconstruction. Long-term follow-up is important to detect recurrences and improve the management of these young patients.     

Towards a Neurotransmitter-Based Retinal Prosthesis Using an Inkjet Print-head

Electronic chips that provide a patterned stimulus to cells in the retina may provide a viable treatment for age-related macular degeneration. A surrogate MEMS device, in the form of a print-head from a desktop printer, has been used to eject a pattern of neurotransmitters (bradykinin) onto living rat pheochromocytoma (PC12) cells. Fluorescent calcium imaging was used to measure the patterned stimulation of individual cells. The chemical stimulation of cells by directed microfluidic delivery may have applications in retinal prosthetic devices, and in other prosthetic implants in the nervous system.