Derby intramedullary nail — A biomechanical comparison

This paper describes the design and function of the Derby intramedullary nail and its biomechanical testing, comparing it with the k nail and reamed unfractured femurs. The Derby nail is designed to transmit torsional loads and apply compression to the fracture site using a sliding proximal collar and distal extendable ‘wings’. Femurs fixed with Derby, K and Zickel nails and AO plates were tested in torsion and the rotation and torsional load at failure recorded and compared with unfractured control femurs. The results show that the strength of the Derby nail in torsion is ≈4 times and the energy to failure 2.3 times that of the k nail.     

顺行髓内钉、逆行髓内钉及锁定加压钢板内固定治疗股骨远端骨折的对比研究

摘要目的：探讨顺行髓内钉、逆行髓内钉及锁定加压钢板内固定3种方法治疗股骨远端骨折患者的疗效。方法：对2011年1月至2012年12月间我院收治的101例股骨远端骨折进行临床随机分组手术,分别在手术中使用顺行髓内钉、逆行髓内钉以及锁定加压钢板内固定。对三组患者手术时间、术中出血量以及切口长度等一般情况进行比较分析,同时采用Harris评分系统对三组患者术后恢复情况进行分析比较。结果：经过手术治疗后,逆行髓内钉组Harris评分显著高于其他两组（P〈0．05）。另外,逆行髓内钉组手术过程短、出血量少、手术切口小,上述指标与其他两组比较均有统计学意义（P〈0．05）。结论：股骨远端骨折行逆行髓内钉治疗的疗效优于顺行髓内钉以及锁定加压钢板内固定,具有手术时间短、术中出血少、切口小等优点,能够有效提高术后膝关节功能的恢复,值得临床推广使用。     

近端膨胀髓内钉与抗旋髓内钉治疗老年股骨转子间骨折的临床疗效分析

目的:探究近端膨胀髓内钉与近端螺旋刀片抗旋髓内钉治疗老年股骨转子间骨折疗效及躁动发生率比较。方法:病例来源为2012年5月至2013年10月收入我院的老年股骨转子间骨折患者60例,采用随机数字表随机分为两组,膨胀钉组30例,采用近端膨胀髓内钉的手术方法,PFNA组30例,采用近端螺旋刀片抗旋髓内钉的手术方法。手术结束后,对两组患者进行X射线片、手术时间及出血量、髋关节功能的比较,同时对比躁动发生率。结果:X线检查结果显示两组患者经手术后骨折处均复位良好,无并发症及内固定物的脱落及松动,两组比较无显著差异(P0.05);与PFNA组相比,膨胀组患者的手术时间及出血量明显降低,差异具有统计学意义(P0.05);两组患者术后3个月、6个月的Harris评分显示,与PFNA组相比,膨胀钉组的优良率明显升高,髋关节优于PFNA组,差异具有统计学意义(P0.05);膨胀钉组患者躁动率为10.00%低于PFNA组患者躁动率为33.33%,具有统计学意义(P0.05)。结论:可膨胀髓内钉具有手术时间较短、出血量少,更利于骨折的愈合,且躁动发生率较低,对股骨转子间骨折的疗效优于较近端螺旋刀片抗旋髓内钉,对临床有指导意义,值得临床推广。     

半髋关节置换治疗高龄老年人不稳定转子间骨折的效果研究

目的:探讨半髋关节置换术治疗老年不稳定性转子间骨折的治疗效果。方法:选择我院骨科2013年1月至2015年2月入院的老年不稳定转子间骨折患者64例,随机分为半髋关节置换组和髓内钉固定组,对两组手术时间、术中出血量、术后并发症、术后髋关节功能恢复状况进行评价。结果:半髋关节置换组手术时间较髓内钉固定组短(P0.05),半髋关节置换组和髓内钉固定组术中出血量、手术后并发症、髋关节功能恢复状况的差异不具有统计学意义(P0.05)。结论:半髋关节置换术治疗老年不稳定性转子间骨折具有较好的临床效果。     

MIPO技术结合锁定加压钢板、顺行交锁髓内钉及锁定加压钢板治疗肱骨干中段骨折疗效的对比研究

摘要 目的：探讨微创经皮钢板内固定（MIPO）技术结合锁定加压钢板、顺行交锁髓内钉、锁定加压钢板治疗肱骨干中段骨折的疗效。方法：选择2016年2月至2019年2月我院收治的126例肱骨干中段骨折患者，采用随机数字表法将其分为三组，MIPO组（42例）采用MIPO技术结合锁定加压钢板固定治疗，髓内钉组（42例）采用顺行交锁髓内钉固定治疗，钢板组（42例）采用锁定加压钢板固定治疗。所有患者术后随访12个月，比较三组手术时间、术中出血量、术后住院时间、骨折愈合时间、术前和术后第12个月美国加州大学肩关节评分系统（UCLA）评分、Mayo肘关节功能评分（MEPS）、欧洲五维健康量表(EQ-5D)评分以及并发症发生率。结果：MIPO组和髓内钉组的术中出血量与术后住院时间均少于钢板组（P＜0.05），MIPO组和髓内钉组之间无统计学差异（P＞0.05）。MIPO组、钢板组骨折愈合时间短于髓内钉组（P＜0.05），MIPO组、钢板组之间无统计学差异（P＞0.05）。MIPO组、钢板组术后第12个月UCLA评分均高于髓内钉组（P＜0.05），MIPO组、钢板组之间无统计学差异，第12个月MEPS无差异（P＞0.05）。术后第12个月MIPO组、钢板组EQ-5D评分高于髓内钉组（P＜0.05），MIPO组、钢板组之间无统计学差异（P＞0.05）。三组桡神经损伤、肩峰损伤发生率相比较，差异有统计学意义（P＜0.05），桡神经损伤以钢板组发生率最高，肩峰损伤以髓内钉组发生率最高。结论：MIPO技术结合锁定加压钢板具有微创、术后恢复快、对肩关节功能及生活质量的影响较小、术后并发症较少的优势，是肱骨干中段骨折较为理想的治疗方式。     

胫骨髓内钉入路治疗胫骨干骨折的临床进展

胫骨干骨折是最常见的长骨骨折,对于不稳定的胫骨骨折,胫骨髓内钉因其独特的优势逐渐成为首选治疗方式。当前对于胫骨干髓内钉入路主要分为髌骨上入路和髌骨下入路。髌骨上入路放置髓内钉时,患肢半伸直位有利于胫骨干骨折的复位与固定,但可能会造成髌骨关节面损伤。髌骨下入路患肢屈曲位可能会造成胫骨干复位的丢失,进而影响患者的预后。因此,胫骨髓内钉置入不同入路可能造成不同临床结局,会对临床结局造成不同的影响。目前对于胫骨髓内钉最佳入路仍然存在争议,针对最近发表的相关文献我们对胫骨髓内钉入路及其优缺点进行讨论综述。     

A novel surgical procedure for bridging of massive bone defects

BACKGROUND: Bony defects arising from tumor resection or debridement after infection, non-union or trauma present a challenging problem to orthopedic surgeons, as well as patients due to compliance issues. Current treatment options are time intensive, require more than one operation and are associated with high rate of complications. For this reason, we developed a new surgical procedure to bridge a massive long bone defect. METHODS: To bridge the gap, an in situ periosteal sleeve is elevated circumferentially off of healthy diaphyseal bone adjacent to the bone defect. Then, the adjacent bone is osteotomized and the transport segment is moved along an intramedullary nail, out of the periosteal sleeve and into the original diaphyseal defect, where it is docked. Vascularity is maintained through retention of the soft tissue attachments to the in situ periosteal sleeve. In addition, periosteal osteogenesis can be augmented through utilization of cancellous bone graft or in situ cortical bone adherent to the periosteal sleeve. RESULTS: The proposed procedure is novel in that it exploits the osteogenic potential of the periosteum by replacing the defect arising from resection of tissue out of a pathological area with a defect in a healthy area of tissue, through transport of the adjacent bone segment. Furthermore, the proposed procedure has several advantages over the current standard of care including ease of implementation, rapid patient mobilization, and no need for specialized implants (intramedullary nails are standard inventory for surgical oncology and trauma departments) or costly orthobiologics. CONCLUSIONS: The proposed procedure offers a viable and potentially preferable alternative to the current standard treatment modalities, particularly in areas of the world where few surgeons are trained for procedures such as distraction osteogenesis (e.g. the Ilizarov procedure) as well as areas of the world where surgeons have little access to expensive, complex devices and orthobiologics.     

Bone remodelling analysis of a bovine femur for a veterinary implant design

The response of bovine bone to the presence of an implant is analysed with the aim of simulating bone remodelling in a developing model of a polymeric intramedullary interlocking nail for veterinary use. A 3-D finite element model of the femur diaphysis is built based on computed tomography images and using a CAD-based modelling pipeline. The bone remodelling process after the surgery is analysed and compared with the healthy bone. The remodelling law assumes that bone adapts to the mechanical environment. For the analyses a consistent set of loads is determined for the bovine walk cycle. The remodelling results reproduce the morphologic features of bone and provide evidence of the difference on the bone behaviour when comparing metallic and polymeric nails. Our findings indicate that an intramedullary polymeric nail has the advantage over the metallic one of improving long-term bone healing and possibly avoiding the need of the implant removal.     

Evaluation of the mechanical properties and clinical application of nickel–titanium shape memory alloy scaphoid arc nail

To investigate the mechanical and biomechanical properties of nickel–titanium (Ni–Ti) shape memory alloy scaphoid arc nail (NT‐SAN) fixator as well as study the surgical method of treating carpal scaphoid fractures and evaluate its clinical efficacy. (1) Static and dynamic bending tests with embedded axial bending fixture were conducted to study the mechanical properties. (2) To evaluate biomechanical strength and fatigue, 32 scaphoid samples were classified into four groups to perform the fixation rigidity test: intramedullary Kirschner fixation (group A), Kirschner straddle nail fixation (group B), screw nail fixation (group C), and NT‐SAN fixation (group D). Next, 24 scaphoid waist fracture models were classified to conduct fatigue experiments as follows: Kirschner straddle nail fixation (group E), screw nail fixation (group F), and NT‐SAN fixation (group G). (3) The Krimmer score chart was used for clinical evaluations. (1) NT‐SAN showed excellent mechanical performance and a long lifespan. (2) NT‐SAN was fixated with a strong intensity and an anti‐fatigue outcome. (3) Ninety‐eight interviewed patients were satisfied with the therapeutic effects of the arc nail (satisfaction rate: 95.92%). The designed strength and hardness of NT‐SAN corresponded with the anatomical characteristics of the scaphoid, and the designed mechanical properties met the biomechanical requirements of a scaphoid fracture. The fatigue strength can meet the requirements of bone healing after the scaphoid fracture. Clinical trials on NT‐SAN scaphoid fracture treatment have shown that the surgery is simple and the clinical results are satisfactory. The therapeutic level of NT‐SAN is III; thus, it is worth promoting.     

交锁髓内钉与经皮锁定钢板治疗胫骨骨折的临床对照研究

目的:探讨交锁髓内钉与经皮锁定钢板治疗胫骨骨折的疗效。方法:选取了100例胫骨骨折患者,按住院单双号分为两组,对照组(48例)给予交锁髓内钉,观察组(52例)给予经皮锁定钢板治疗。通过观察并记录疗效,围手术期指标及随访3个月的并发症发生情况,评价交锁髓内钉与经皮锁定钢板治疗胫骨骨折的疗效。结果:采用经皮锁定钢板内固定和交锁髓内钉治疗胫骨骨折,两种手术方法所需手术时间无统计学差异(P0.05),经皮锁定钢板内固定术术中出血量更少,术后观察组患者住院时间和骨折愈合时间更短(P0.05),术后3个月,观察组患者有效率明显高于对照组(P0.05),随访3个月期间,观察组并发症5例,发生率9.6%,对照组并发症12例,发生率25.0%,观察组并发症发生率明显低于对照组(P0.05)。结论:经皮锁定钢板对胫骨骨折具有较好的疗效,手术安全性高,并发症少,能促进骨折愈合,使患者尽早康复,值得临床推广使用。     

动力髋螺钉与股骨近端髓内钉治疗老年股骨近端骨折的临床疗效比较

目的:比较动力髋螺钉与股骨近端髓内钉治疗老年股骨近端骨折的临床疗效和安全性。方法:收集我院收治的老年股骨近端骨折患者64例,随机分为DHS组和PFN组,每组各32例。DHS组患者给予动力髋螺钉的固定方式,PFN组给予股骨近端髓内钉的固定方式。手术后对患者的手术切口长度、术中出血量、手术时间、骨折愈合时间、术后并发症以及患者临床疗效进行检测并比较。结果:与治疗前相比,两组患者治疗后的Harris评分均显著下降(P0.05);与DHS组相比,PFN组患者的手术切口长度、术中出血量、手术时间、骨折愈合时间、术后并发症的发生率以及Harris评分均较低(P0.05)。结论:股骨近端髓内钉的固定治疗老年股骨近端骨折的临床疗效较好,安全性更高。     

髓内钉InterTan 治疗股骨近端骨折的早期疗效分析

目的:分析应用新一代股骨近端髓内钉( InterTan)治疗股骨近端骨折的早期临床疗效.方法:回顾性分析2009年9月至201 1年8月我科共收治股骨近端骨折患者共107例,均采用InterTan髓内钉系统进行治疗,其中男45例,女62例;年龄34-93岁,平均73.05岁.受伤肢体左侧63例,右侧44例.按AO分型,31-A1型32例,31 -A2型59例,31-A3型16例.记录患者手术持续时间、并发症、死亡率、骨折愈合时间、末次复查Harris评分,并对比患者健侧及患侧术前、术中及术后1周的颈干角变化.所有数据采用SPSS 13.0进行统计分析.结果:平均手术持续时间为66.69分钟.颈干角:术前健侧:140.66±9.08度,术前患侧:118.00± 15.49度,术中患侧:135.16± 7.08度,术后1周患侧:137.51±15.21度.术前患侧颈干角与其他三组相比均有显著性差异(P＜0.05),术前健侧、术中复位后患侧、术后1周患侧颈干角之间相比均无显著性差异.3例患者于随访过程中死亡,6例患者失访.98例患者获得随访,随访时间3 -22个月,平均8.6个月.2例患者发生头钉切出,3例患者术后练习后出现股骨疼痛症状,未发生股骨干骨折.96例患者均获得骨性愈合,骨折愈合时间12～18周.临床疗效按Harris评分标准:41-92分,平均78.5分,优良率80.6％.结论:髓内钉InterTan是治疗股骨近端骨折的良好选择.     

弹性髓内钉与接骨板内固定治疗儿童股骨干骨折的临床疗效对比研究

摘要 目的：对比弹性髓内钉与接骨板内固定治疗儿童股骨干骨折的临床疗效。方法：本研究为回顾性研究,选取我院于2018年3月~2019年8月期间收治的儿童股骨干骨折患者98例,根据固定方式的不同将患儿分为A组（n=50,接骨板内固定治疗）和B组（n=48,弹性髓内钉治疗）,观察两组优良率、术前/术后相关指标及并发症发生情况。结果：B组的优良率高于A组（P<0.05）。B组手术时间、切口长度短于A组,术中出血量少于A组（P<0.05）。B组骨折愈合时间、住院时间、手术至内固定拆除时间、取出内固定手术时间短于A组（P<0.05）。两组患儿并发症发生率对比,差异无统计学意义（P>0.05）。结论：相对于接骨板内固定治疗,弹性髓内钉治疗儿童股骨干骨折,疗效更好,可有效改善术中、术后指标,且不增加并发症的发生率。     

人工髋关节置换和内固定治疗复杂股骨转子间骨折的疗效及对预后的影响

目的:对比人工髋关节置换和内固定治疗复杂股骨转子间骨折的疗效及对预后的影响。方法:选择2008年1月~2012年5月我院骨科收治的复杂股骨转子间骨折患者85例,按知情同意原则分成人工髋关节置换组(A组,46例)及内固定组(B组,39例)2组,记录患者的一般临床资料及治疗情况,比较两组患者疗效指标及预后指标。结果:A组患者卧床时间低于B组患者,差别有统计学意义(P0.05);术后1、3、6个月的Harris评分情况A组均优于B组患者,差异有统计学意义(P0.05)。结论:人工髋关节置换治疗复杂股骨转子间骨折能有效缩短患者卧床时间,迅速恢复关节功能,远期疗效效果好。     

Numerical investigation of mechanical effects caused by various fixation positions on a new radius intramedullary nail

Fracture of the radius diaphysis is an unusual injury in adults. Open reduction and plate osteosynthesis has been recommended by most of the authors. However, this trend has started to change with the recent introduction of newly designed interlocking intramedullary (IM) nails. New generation of IM nails are developed in order to utilise the advantages of IM nails against plates. Because of its anatomical structure, the radius bone has a complex geometry. Therefore, the callus structure, which forms during the healing period, should not be affected from external effects, such as excessive loads or motion. In this study, effects of radial styloid process (RSP), dorsal side and ulnar notch edge fixations of a new design radius IM nail on the healing period were numerically investigated. A three-dimensional solid model of radius was obtained from computed tomography images of a volunteer and callus structure model, was placed accordingly and different fixations of implants were performed. The models were analysed under axial loads transferring from the wrist to the radius bone using finite element method. As a result of the analysis, fixation of IM nail from RSP was found to be beneficial on healing period in terms of both callus motion and emerging stresses.     

Development of a locking femur nail for mice

We herein report on a novel locking intramedullary nail system in a murine closed femur fracture model. The nail system consists of a modified 24-gauge injection needle and a 0.1-mm-diameter tungsten guide wire. Rotation stability was accomplished by flattening the proximal and distal end of the needle. Torsional mechanical testing of the implants in osteotomized cadaveric femora revealed a superiority of the locking nail (3.9+/-1.0 degrees rotation at a torque of 0.9 Nmm, n=10) compared to the unmodified injection needle (conventional nail; 52.4+/-3.2 degrees, n=10, p<0.05). None of the implants, however, achieved the rotation stability of unfractured femora (0.3+/-0.5 degrees, n=10). In a second step, we tested the feasibility of the in vivo application of the locking nail to stabilize a closed femoral midshaft fracture in C57BL/6 mice. Of interest, none of the 10 animals showed a dislocation of the locking nail over a 5-week period, while 3 of 4 animals with conventional nail fracture stabilization showed a significant pin dislocation within the first 3 days (p<0.05). Mechanical testing after 5-weeks stabilization with the locking nail revealed an appropriate bone healing with a torque at failure of 71.6+/-3.4% and a peak rotation before failure of 68.4+/-5.3% relative to the unfractured contralateral femur. With the advantage that closed fractures can be fixed with rotation stability, the herein introduced model may represent an ideal tool to study bone healing in transgenic and knockout mice.     

扩髓更换髓内钉治疗髓内钉固定后股骨干肥大性骨不连

目的:评价扩髓更换髓内钉治疗髓内钉固定后股骨干肥大性骨不连的临床疗效及手术适应症。方法:自1998年4月至2009年6月采用扩髓更换髓内钉治疗11例髓内钉固定后股骨干肥大性骨不连,其中男9例,女2例,年龄23-61岁。平均36.2岁,骨折部位在股骨上1/3者2例;中1/3者6例;下1/3者3例,原始骨折Winquist-Hansen分型:I型2例,II型3例,III型4例,IV型2例。结果:11例患者均获随访,时间:11～56个月,平均27.4个月,2例患肢短缩1 cm。另4例未获得骨性愈合,3例再次采用附加钢板合并自体髂骨植骨,1例远端锁钉动力化,再次干预后获得骨性愈合,愈合时间6～16个月,平均8.3个月。结论:扩髓更换髓内钉是治疗髓内钉固定后股骨肥大性骨不连的传统方法,基于力学稳定和临床观察,更适用于股骨中段骨不连。     

Nail position has an influence on anterior knee pain after tibial intramedullary nailing

Our aim was to determine the possible relationship between anterior knee pain (AKP) and nail position marked as a distance from tip of nail to tibial plateau (NP) and to the tuberositas tibiae (NT). Nail position has an influence on anterior knee pain after tibial intramedullary nailing. We evaluated postoperative outcome results of 50 patients in the last 3 years with healed fractures initially treated with intramedullary (IM) reamed nails with 2 or 3 interlocking screws on both parts of the nail and with the use of medial paratendinous incision for nail entry portal. Patients marked a point on the visual analog scale (VAS) that corresponded to the level of postoperative AKP felt. Two groups of patients were formed on the basis of AKP (pain level was neglected): groups A and B, with and without pain, respectively. The difference between the two groups concerning NP measurements was statistically significant (p < 0.05), but not concerning NT measurements at the p < 0.05 level. Patients were classified by pain with high accuracy (98%) according to a classification tree. Symptoms of AKP did not appear if the tip of the nail position was more than 6.0 mm from the NP and more than 2.6 mm from the NT. However, for better evaluation of these results it will be necessary to examine a larger number of postoperative patients with AKP.     

SPI-23 of S. Derby: Role in Adherence and Invasion of Porcine Tissues

Salmonella enterica serovars Derby and Mbandaka are isolated from different groups of livestock species in the UK. S. Derby is predominantly isolated from pigs and turkeys and S. Mbandaka is predominantly isolated from cattle and chickens. Alignment of the genome sequences of two isolates of each serovar led to the discovery of a new putative Salmonella pathogenicity island, SPI-23, in the chromosome sequence of S. Derby isolates. SPI-23 is 37 kb in length and contains 42 ORFs, ten of which are putative type III effector proteins. In this study we use porcine jejunum derived cell line IPEC-J2 and in vitro organ culture of porcine jejunum and colon, to characterise the association and invasion rates of S. Derby and S. Mbandaka, and tissue tropism of S. Derby respectively. We show that S. Derby invades and associates to an IPEC-J2 monolayer in significantly greater numbers than S. Mbandaka, and that S. Derby preferentially attaches to porcine jejunum over colon explants. We also show that nine genes across SPI-23 are up-regulated to a greater degree in the jejunum compared to the colon explants. Furthermore, we constructed a mutant of the highly up-regulated, pilV-like gene, potR, and find that it produces an excess of surface pili compared to the parent strain which form a strong agglutinating phenotype interfering with association and invasion of IPEC-J2 monolayers. We suggest that potR may play a role in tissue tropism.     

Biomechanical assessment and clinical analysis of different intramedullary nailing systems for oblique fractures

The aim of this study is to evaluate the fracture union or non-union for a specific patient that presented oblique fractures in tibia and fibula, using a mechanistic-based bone healing model. Normally, this kind of fractures can be treated through an intramedullary nail using two possible configurations that depends on the mechanical stabilisation: static and dynamic. Both cases are simulated under different fracture geometries in order to understand the effect of the mechanical stabilisation on the fracture healing outcome. The results of both simulations are in good agreement with previous clinical experience. From the results, it is demonstrated that the dynamization of the fracture improves healing in comparison with a static or rigid fixation of the fracture. This work shows the versatility and potential of a mechanistic-based bone healing model to predict the final outcome (union, non-union, delayed union) of realistic 3D fractures where even more than one bone is involved.