胫骨远端前外侧解剖型锁定钢板治疗不稳定性Pilon骨折的生物力学研究

目的探讨胫骨远端前外侧解剖型锁定钢板治疗不稳定性Pilon骨折的生物力学性能。方法将7具新鲜湿润的成人踝关节标本随机分为四组,1具标本作为正常对照组(N组);其余6具均造成胫骨远端不稳定性Pilon骨折,分成3组,每组2具标本,分别采用胫骨远端前外侧解剖型锁定钢板(A组)、三叶草钢板(B组)、重建钢板固定(C组),后两组为对照组,测试各组的远端轴向强度、刚度,扭转生物力学性能,胫距关节面接触特征。结果 A组在胫骨远端不稳定性Pilon骨折的远端轴向强度、刚度,扭转生物力学性能以及胫距关节面接触特征上接近N组(P0.05),优于B、C组(P0.05)。结论胫骨远端前外侧解剖型锁定钢板治疗不稳定性Pilon骨折不但具有优越的生物力学性能,而且操作简便、安全可靠,Pilon骨折固定的关节稳定性明显比其他内固定材料占有较大的优势,是较为理想的选择。     

胫骨远端后侧解剖型锁定钢板治疗胫骨远端骨折的生物力学研究分析

[目的]探究胫骨远端后侧解剖型锁定钢板治疗胫骨远端骨折的生物力学特性。[方法]选取福建省闽东卫生学校解剖教研室提供的新鲜成人踝关节标本16具,其中4具作为正常对照组(正常组),其余12具制备成胫骨远端不稳定性骨折标本。将骨折标本随机分为胫骨远端后侧解剖型锁定钢板固定组(后侧钢板组)、胫骨远端内侧解剖型锁定钢板固定组(内侧钢板组)和三叶草钢板固定组(三叶草钢板组)各4具。比较各组标本的强度、轴向刚度、扭转力学性能以及胫距关节面接触特征。[结果]后侧钢板组胫骨远端平均强度与平均轴向刚度均显著高于内侧钢板组、三叶草钢板组两组,差异具有统计学意义(P<0.05),与正常组差异无统计学意义(P>0.05)。后侧钢板组平均扭矩与扭转刚度均显著高于内侧钢板组、三叶草钢板组两组,差异具有统计学意义(P<0.05),与正常组差异无统计学意义(P>0.05)。800 N作用力下,后侧钢板组平均接触面积>内侧钢板组、三叶草钢板组两组,平均接触应力<内侧钢板组、三叶草钢板组两组,与正常组差异无统计学意义(P>0.05)。[结论]与胫骨远端内侧解剖型锁定钢板和三叶草钢板相比,后侧解剖型锁定钢板内固定治疗胫骨远端不稳定性骨折的生物力学性质更佳,与正常胫距关节面的解剖形态相近,且操作简便,是一种新型适合于胫骨远端后侧的内固定材料。     

Pilon骨折

胫骨Pilon骨折一般是指胫骨远端1／3波及胫距关节面的骨折,胫骨远端关节面严重粉碎,骨缺损及远端松质骨压缩。常合并有腓骨下段骨折（约75％-85％）和严重软组织挫伤。Pilon骨折应包括：（1）踝关节和胫骨远端的干骺端骨折,通常伴有踝关节的关节面粉碎性骨折;（2）内踝骨折;（3）胫骨前缘骨折;（4）胫骨后面横形骨折。     

胫骨远端LCP结合外固定支架术中辅助复位治疗Pilon骨折

目的探讨胫骨远端锁定加压钢板（locking compression plate,LCP）结合外固定支架术中辅助复位治疗Pilon骨折方法和疗效。方法自2007年8月至2011年12月,采用胫骨远端LCP结合外固定支架术中辅助复位治疗Pilon骨折15例,以外固定支架恢复并维持胫距关节的高度、力线,使用微创经皮钢板内固定技术置入胫骨远端LCP,并在胫骨远端以较多的锁定螺钉（5～7枚）固定和支撑胫距关节面及植骨。结果本组15例患者全部获得随访,随访时间11～20个月,平均13个月。全部获得骨性愈合,术后踝关节功能评估优良率达86.7%。结论胫骨远端LCP结合外固定支架术中辅助复位是治疗Pilon骨折的有效方法。本治疗方法解决了手术治疗Pilon骨折时复位困难、复位难以维持的问题。     

不同方法固定胫骨不稳定 pilon 骨折的生物力学研究

目的 探讨不同方法 固定胫骨不稳定pilon骨折的生物力学性能. 方法 用7具新鲜国人踝关节标本制备Ruedi-Allgower Ⅲ型pilon骨折,根据不同固定方法 分5组,A组:内侧支撑钢板固定,B组:胫骨远端前外侧解剖型钢板加内侧空心钉固定,C组:外侧外固定支架加内侧空心钉固定,D组:外侧外固定支架加内侧支撑钢板固定,E组:内侧外固定支架加胫骨远端前外侧解剖型钢板固定.比较各组的强度、刚度、失效载荷等生物力学性能. 结果 A、B、C、D、E组胫骨远端的抗压应力值分别为(1.31±0.10)、(1.61±0.14)、(1.17±0.13)、(0.90±0.08)、(0.98±0.08)MPa,轴向刚度分别为(1224.49±115.40)、(1016.95±102.32)、(1395.34±140.12)、(1935.48±180.42)、(1764.71±174.76)N/mm,水平剪切刚度分别为(3076.92±304.20)、(2553.19±250.73)、(3529.41±344.42)、(4800.00±490.61)、(4444.45±451.52)N/mm,失效载荷分别为(2448±208)、(2034±184)、(2791±265)、(3871±382)、(3529±342)N,等效刚度值分别为(703±56)、(583±62)、(805±74)、(1100±108)、(1035±110)N·m/Deg. 结论 对于胫骨不稳定性pilon骨折,采用胫骨内侧支撑钢板或胫骨远端前外侧解剖型钢板附加外固定支架固定,不但具有优越的生物力学性能,等效刚度高,而且固定坚强、可靠,操作方便,踝关节稳定性好,为Ruedi-Allgower Ⅲ型pilon骨折切开复位手术固定选择提供了理论参考.     

胫骨远端解剖钢板治疗Pilon骨折

目的：探讨胫骨远端解剖钢板治疗Pilon骨折手术时机和疗效。方法：对1995-2000年接受手术治疗的45例Pilon骨折患者进行随访。骨折类型：Ⅰ型14例，Ⅱ型16例，Ⅲ型15例。22例行切开复位胫骨远端解剖钢板内固定，23例行有限切开内固定辅以外固定。术后平均随访40.8月。结果：按Mazur评分系统，45例中优37例，良5例，可2例，差1例。术后并发症：伤口不愈合（4例），伤口感染（2例），骨折延迟愈合（1例），踝关节肿胀（8例），踝关节僵硬（1例）。结论：治疗方法的选择应遵循个体化原则。术前伤品处理、术中关节面解剖复位和应用解剖钢板坚强内固定是提高Pilon骨折临床疗效的有效措施。     

单侧组合式外固定器治疗胫骨远端干骺端骨折

目的探讨应用单侧组合式外固定器结合选择正确的腓骨固定方法治疗胫骨远端干骺端骨折的效果。方法对31例胫骨远端干骺端骨折AO分型为A、B、C型骨折的患者进行治疗。腓骨骨折固定：A型不予固定;B、C型位于下胫腓联合上〈5 cm者用1/3管形钢板内固定,高位者不予固定,B型下胫腓联合以下者可不予固定,C型下胫腓联合以下者行腓骨远端解剖钢板固定。胫骨骨折固定：A、B型行闭合复位外固定器固定,C型行切开克氏针内固定后再用外固定器固定。并对该方法的治疗结果进行评估。结果 31例均获随访,时间6～23（16&#177;7）个月。关节面复位：优26例,良3例,差2例;肢体力线恢复：优27例,良3例,差1例。Phil-lips＆Shwart踝关节评分为78～92（85&#177;0.3）分。结论根据骨折类型,用单侧组合式外固定器固定结合选择正确的腓骨固定方式可有效避免伤口并发症,更好地恢复骨折端的解剖复位,固定牢固,疗效好。     

胫骨Pilon骨折手术治疗方法的选择及临床疗效分析

目的通过对严重胫骨Pilon骨折患者行不同内固定物手术治疗,观察其临床疗效。方法选取2011年11月至2013年12月来我院诊治的胫骨Pilon骨折120例患者,通过术前检查及常规术前处理,分别行胫骨远端解剖钢板、胫骨远端锁定钢板及有限内固定结合外固定架手术治疗.术后观察3组骨折愈合时间、术后并发症发生及术后踝关节功能恢复情况,并发症包括伤口有无感染、内固定物是否松动及骨髓炎是否发生。踝关节功能恢复根据Mazur评价标准。结果胫骨远端锁定钢板组术后骨折愈合时间及踝关节功能恢复优于其他两组,且并发症的发生少于其他两组,胫骨远端锁定钢板组与其他两组比较有统计学差异性（P〈0.05）。解剖钢板组与有限内固定结合外固定架组组间比较差异无统计学意义（P〉0.05）。结论虽然解剖钢板和有限内固定结合外固定架内固定物在治疗严重胫骨Pilon骨折效果较好,但本文认为胫骨远端锁定钢板在治疗此类骨折效果更佳,值得临床广泛应用。     

三种新型内固定方式治疗胫骨平台双髁四象限骨折的有限元研究

目的 通过有限元分析比较3种新型内固定方式治疗胫骨平台双髁四象限骨折的生物力学差异,探讨最符合力学原理的内固定方式。方法 利用1名健康男性志愿者胫骨平台CT图像数据,采用有限元分析软件建立胫骨平台双髁四象限骨折模型。在此基础上,建立3组内固定有限元模型。其中,A、B、C组前外侧均为倒L形解剖锁定钢板固定;A组前内侧、后内侧重建钢板纵向固定,后外侧重建钢板斜向固定;B、C组内侧胫骨近端T形钢板固定后,重建钢板分别纵向固定后内侧、斜向固定后外侧。于胫骨平台施加1 200 N轴向载荷（模拟体质量60 kg成年人生理步态下行走情况）,观测3组骨折块整体发生的最大位移和胫骨、骨折缝、内植物的最大Von-Mises应力。结果 有限元分析示各组胫骨应力集中分布于骨折缝及螺纹连接处,内植物应力集中分布于骨折块部位螺钉连接处。施加1 200 N轴向载荷时,3组模型骨折块最大位移相近,其中A组最大（0.74 mm）,B组最小（0.65 mm）。内植物承受的最大Von-Mises应力C组最小（95.49 MPa）,B组最大（177.96 MPa）;胫骨承受的最大Von-Mises应力C组最小（43.35 M...     

Pilon骨折的术前评估与治疗进展

正胫骨远端Pilon骨折,也称作Pilon骨折,指胫骨远端关节面在受到轴向暴力引起的胫骨远端关节内压缩塌陷型骨折。Pilon骨折常因高能量暴力导致关节面损伤严重且伴有严重的软组织损伤。Pilon骨折因其关节面损伤严重,常须手术治疗,Rüedi和Allg?wer最早描述了Pilon骨折的分型及其治疗。Pilon骨折的手术治疗复杂,临床预后并发症较多。本文主要总结分析了近年来Pilon骨折的术前评估与分型、切口选择、内固定选择及治疗方法,并对本期发表的相关文章进行点评。     

双钢板夹持内固定治疗Ruedi—AllgowerⅢ型Pilon骨折的三维有限元分析

目的 探讨双钢板夹持内固定治疗Ruedi—AllgowerⅢ型Pilon骨折的生物力学性能,为临床应用提供科学依据。方法 应用三维有限元方法模拟Ruedi—AllgowerⅢ型Pilon骨折,分别应用双钢板、胫骨远端内侧解剖板、胫骨远端外侧解剖板固定骨折,对模型施以500N的垂直轴向载荷,计算固定后骨折块间及钢板的最大位移,并将加载下的骨应力分布同正常胫骨加载下的应力分布进行比较。结果 3种固定中,双钢板固定最牢固,双钢板在加载下的应力分布与正常胫骨相似。结论 采用双钢板夹持内固定治疗Ruedi—AllgowerⅢ型Pilon骨折,固定牢固,在力学性能上,能保证骨折以最佳方式愈合。     

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.     

Calcar screw position in proximal humerus fracture fixation: Don’t miss high!

IntroductionIn locked plate fixation of proximal humerus fractures, the calcar is an important anchor point for screws providing much-needed medial column support. Most locking plate implants utilize a fixed-trajectory locking screw to achieve this goal. Consequently, adjustments of plate location to account for patient-specific anatomy may result in a screw position outside of the calcar. To date, little is known about the consequences of “missing” the calcar during plate positioning. This study sought to characterize the biomechanics associated with proximal and distal placement of locking plates in a two-part fracture model.Materials and methodsThis experiment was performed twice, first with elderly cadaveric specimens and again with osteoporotic sawbones. Two-part fractures were simulated and specimens were divided to represent proximal, neutral, and distal plate placements. Non-destructive torsional and axial compression tests were performed prior to an axial fatigue test and a ramp to failure. Torsional stiffness, axial stiffness, humeral head displacement and stiffness during fatigue testing, and ultimate load were compared between groups.ResultsCadavers: Proximal implant placement led to trends of decreased mechanical properties, but there were no significant differences found between groups. Sawbones: Distal placement increased torsional stiffness in both directions (p = 0.003, p = 0.034) and axial stiffness (p = 0.018) when compared to proximal placement. Distal placement also increased torsional stiffness in external rotation (p = 0.020), increased axial stiffness (p = 0.024), decreased humeral head displacement during fatigue testing, and increased stiffness during fatigue testing when compared to neutral placement.DiscussionThe distal and neutral groups had similar mechanical properties in many cadaveric comparisons while the proximal group trended towards decreased construct stiffness.Resultsfrom the Sawbones model were more definitive and provided further evidence that proximal calcar screw placements are undesirable and distal implant placement may provide improved construct stability.ConclusionSuccessful proximal humerus fracture reconstruction is inherent upon anatomic fracture reduction coupled with medial column support. Results from this experiment suggest that missing the calcar proximally is deleterious to fixation strength, while it is safe, and perhaps even desirable, to aim slightly distal to the intended target.     

手术时机选择对胫骨Pilon骨折手术疗效的影响

目的：评估伤后手术时机选择对胫骨Pilon骨折疗效的影响。方法：选取自2003年6月至2008年5月有随访记录的65例胫骨Pilon骨折患者,男42例,女23例;年龄15～62岁,平均（37.53±6.32）岁。按受伤至手术时间分为两组,A组30例,伤后3～7d行切开复位植骨解剖钢板内固定术;B组35例,采用分步延期开放复位内固定,于伤后7～24d软组织肿胀消退后行切开复位植骨内固定术。术后观察两组创面及骨折愈合情况,参照Bourne对胫骨Pilon骨折的愈合评价进行踝关节功能评估。结果：65例患者均获得随访,时间7～24个月,平均16.23个月。A组3例并发感染,4例刀口裂开,1例内固定物外露,1例骨髓炎;B组2例表浅感染,其余全部Ⅰ期愈合,B组在伤口愈合方面明显优于A组。A组患者的骨折愈合时间为（18.3±3.2）周,B组为（15.7±2.5）周,A组骨折愈合时间明显长于B组（P〈0.05）。参照Bourne对胫骨Pilon骨折的愈合评价：A组优12例,良10例,差8例,优良率为73.3%;B组优21例,良8例,差6例,优良率为82.9%,B组优于A组（P〈0.05）。结论：手术时机的选择是高能量胫骨Pilon骨折治疗的关键,选择合适的手术时机,采用分步延期开放复位内固定是治疗高能量胫骨Pilon骨折有效的方法。     

微创经皮解剖钢板治疗胫骨远端骨折的病例对照研究

目的:探讨应用经皮微创钢板固定(minimally invasive percutaneous plate osteosynthesis,MIPPO)技术治疗胫骨远端骨折的临床疗效。方法:对2006年2月至2009年3月收治的87例胫骨远端骨折患者的临床资料进行回顾性分析。经皮微创解剖钢板固定组(A组)35例,男25例,女10例;年龄(34.12±7.10)岁;采用闭合复位、解剖钢板内固定;经皮微创锁定钢板固定组(B组)11例,男8例,女3例;年龄(29.03±4.12)岁;采用闭合复位、锁定钢板内固定;传统切口解剖钢板固定组(C组)26例,男15例,女11例;年龄(31.07±6.31)岁;采用切开复位、解剖钢板内固定;传统切口锁定钢板固定组(D组)15例,男9例,女6例;年龄(30.27±6.52)岁;采用切开复位、锁定钢板内固定。比较4组手术时间、术中出血量、住院时间、住院费用、骨折愈合时间、末次随访AOFOS评分、并发症发生情况等指标。结果:87例均获随访,时间16～48个月,平均(24.6±2.2)个月。4组手术时间、末次随访AOFOS评分差异均无统计学意义。A、B组的术中出血量少于C、D组,住院时间、骨折愈合时间短于C、D组。A、C组的住院费用少于B、D组。结论:应用微创内固定技术创伤小、住院时间短,特别是应用经皮微创技术结合传统解剖钢板能够降低医疗费用。     

Indentation stiffness of the cancellous bone in the distal human tibia

Total ankle arthroplasties tend to fail mainly on the tibial side. Fifteen fresh amputation specimens were used for assessment of the stiffness of the cancellous bone in the distal tibia. Because all current ankle replacements sacrifice the subchondral bone plate, the change in stiffness of cancellous bone was studied in transverse sections taken proximal to the subchondral plate of the ankle. The articular cartilage was removed from the tibial plafond, and serial 1-cm sections were taken, radiographed, and tested in compression on an Instron 1125 Universal Testing machine with the use of a 4-mm-diameter indentor. In the distal tibia, it was found that subchondral bone has an elastic modulus on the order of 300-450 MPa; removal of the subchondral bone plate reveals bone with a compressive resistance that is 30%-50% lower than with the bone plate intact; there is virtually no resistance to compression in the trabecular bone at a distance of more than 3 cm proximal to the subchondral bone plate; and stiffness characteristics in the distal tibia parallel the radiographic appearance of the trabeculae. The strongest cancellous bone in the region of the distal tibia is that near the subchondral bone plate. This material should be preserved, if possible, in the surgery for total ankle implants.     

Additional fixation of medial plate over the unstable lateral locked plating of distal femur fractures: A biomechanical study

IntroductionLateral locked plating is a standard treatment option for distal femur fractures. However, the unstable conditions after lateral locked plating are increasing. The objective of this study was to investigate the biomechanical strength of additional medial plate fixation over the unstable lateral locked plating of distal femur fractures.Materials and methodsA distal femur fracture model (AO/OTA 33-A3) was created with osteotomies in the composite femur. Three study groups consisting of 6 specimens each were created for single-side lateral locked plating with 6 distal locking screws (LP-6), single-side lateral locked plating with 4 distal locking screws (LP-4), and additional medial locked plating on LP-4 construct (DP-4). A compressive axial load (10 mm/min) was applied in the failure test. Mode of failure, load to failure, and ultimate displacement were documented.ResultsAll single-side lateral locked plating (LP-4 and LP-6) showed plate bending at the fracture gap, while none of the DP-4 showed plate bending at the fracture gap. Load to failure of DP-4 (mean 5522 N) was 17.1% greater than that of LP-6 (mean 4713.3 N, p < 0.05) and 29.2% greater than that of LP-4 (mean 4273.2 N, p < 0.05). Ultimate displacement of DP-4 (mean 5.6 mm) was significantly lower than that of LP-6 (mean 8.8 mm, p < 0.05) and LP-4 (mean 9.1 mm, p < 0.05).ConclusionsAdditional fixation of medial plate significantly increased the fracture stability in distal femur fractures fixed with the lateral locked plating. Especially in the clinical situations where sufficient stability cannot be provided at the distal segment, the medial plate may be considered as a useful biomechanical solution to obtain adequate stability for fracture healing.     

胫骨远端骨折两种治疗方法的疗效比较

目的：评价两种不同方法治疗胫骨远端骨折的临床适应证、并发症及其疗效。方法：45例闭合性胫骨远端骨折采用不同手术方法：A组25例,男18例,女7例;按AO／ASIF分类：A型4例,B型14例,C型7例;采用切开复位解剖型钢板内固定。B组20例,男12例,女8例;A型5例,B型9例,C型6例;采用微创经皮锁定钢板内固定。术后观察患者疼痛程度、切口皮肤坏死、深部感染发生率等并发症以及骨折愈合时间、踝关节运动功能进行对比研究。结果：患者术后随访10-15个月,平均12个月。按视觉模拟量袁（VAS）评分：A组中度-重度,B纽轻度-中度;骨性愈合时间：A组平均（16．0±4．2）周,B组平均（13．0±3．2）周,差异有统计学意义（火0．01）。A组术后并发症发生率高于B组（P〈0．05）。踝关节功能评定按照Kofoed评分标准,术后踝关节功能恢复B组总体优良率明显高于A组（P〈0．05）。结论：微创经皮锁定钢板内固定较切开复位解剖型钢板内固定治疗胫骨远端骨折具有手术创伤小,对骨骼血供影响小,骨折愈合快,并发症少,踝关节功能恢复好的优点,符合生物力学内固定。