膝关节损伤生物材料及其生物力学特点

目的:总结近年对膝关节韧带的生物力学与人工韧带的研究进展,强调膝关节的损伤类型,膝关节前后交叉韧带修复的主要方法及进展.资料来源:以human knee cruciate ligament,biomechanics,xenogeneic ligamentous,reconstruction为检索词,检索PubMed数据库(2008-01/2009-07):以膝关节交叉韧带,生物力学,重建,人工韧带,康复为检索词,检索中国期刊全文数据库(2008-01/2009-07).文献检索语种限制为英文和中文.资料选择:纳入膝关节及人工韧带相关的内容.排除已被证实落后的研究及重复性研究.结局评价指标:①膝关节的生物力学特征.②膝关节韧带损伤的情况.③膝关节韧带的修复与重建方法.结果:计算机初检得到526篇文献,根据纳入排除标准,对膝关节损伤生物材料及其生物力学进行分析.常见的膝关节损伤主要是韧带损伤,为恢复其功能主要采用手术重建,其中利用自体中1/3骨-髌韧带-骨作为移植材料的挤压螺钉内固定重建术,已成为重建前交叉韧带的标准方法.羟基磷灰石是一类具有良好生物相容性的生物活性材料,羟基磷灰石生物活性陶瓷植入体内不仅安全、无毒,还能传导骨生长,即新骨可以从羟基磷灰石植入体与原骨结合处沿着植入体表面或内部贯通性孔隙攀附生长,能与组织在界面上形成化学键性结合.结论:对膝关节及膝关节韧带进行生物力学分析是防止和治疗膝关节损伤及疾病的基础.具有表面羟基磷灰石涂层无螺纹的假体松动率最低,是最适宜的假体置换材料.     

人工生物材料在肌腱损伤中的应用

背景:体育运动训练中肌腱损伤较为常见,肌腱损伤后由于腱鞘的完整性遭到破坏,其愈合周期较长甚至很难康复,随着组织工程学治疗技术应用于运动医学领域,运用人工生物材料干预肌腱损伤后的愈合与康复手段也日趋多样与成熟.目的:对人工材料干预肌腱康复与治疗的手段进行分类与归纳,对肌腱损伤后人工生物材料干预下的康复与治疗手段及机制进行探讨.方法:应用计算机检索PubMed数据库(http://www.ncbi.nlm.nih.gov/PubMed)及CNKI数据库(www.cnki.net/index.htm),在标题和摘要中以"生物材料,肌腱"或"biological material,tendon"为检索词进行检索.选择文章内容与肌腱治疗手段、材料学特点、生物相容性及其应用效果相关,同一领域文献则选择近期发表或发表在权威杂志文章,最终纳入34篇文献.结果与结论:腱鞘是防止肌腱粘连的重要屏障,肌腱损伤后,尤其损伤较为严重时腱鞘的完整性遭到破坏,临床上腱鞘损伤后很难再原位缝合.因此,肌腱损伤后在愈合过程中,如何避免其粘连的形成,是解决肌腱损伤后修复的一个关键问题.现代人工生物材料的妥善运用,为肌腱损伤后的快速良好康复提供了可能及保障.     

生物材料在预防肌腱粘连中的作用

长期以来,肌腱损伤后的修复存在一个关键问题,即粘连的形成使肌腱原有功能降低或丧失.经过多年来众多科学家的共同努力,这方面的研究取得了大量成果,如对肌腱愈合机制的认识逐步深入、肌腱损伤的修补方法及粘连预防的改进均改善了肌腱的愈合效果.文章就目前常用的几种生物材料预防肌腱粘连的作用机制及特点进行了探讨,以便更好地发挥其预防肌腱粘连的作用.     

人工生物材料在肌腱损伤中的应用

目的:着重讨论组织工程在肌腱损伤中的临床应用.方法:应用计算机检索Medline数据库、中国期刊全文数据库1974/2009相关文献,检索词为"生物材料,肌腱愈合机制,预防粘连,Biological material,Sinew mechanism heals",并手工查阅相关书籍.结果:国内外学者不断探索如何在肌腱修复过程中通过内外源性生长因子调控细胞增殖、分化以及基质合成,促进肌腱修复并减少肌腱粘连和生物力学强度的衰减.肌腱缺损的治疗主要有自体肌腱移植、异体肌腱移植、人工肌腱移植、组织工程化肌腱植入,虽各有优缺点,但目前的研究热点是人工生物材料肌腱,且已应用于临床.当然,还有许多问题需要解决:包括肌腱组织工程种子细胞的来源,同种异体肌腱细胞的免疫学反应,特殊力学强度和降解性能支架材料的制备和筛选,细胞与支架材料之间相互作用关系及细胞-材料复合体与周围组织相互关系的问题等.随着人们对肌腱修复愈合理论认识的深入,防止肌腱粘连的药物也从用单一的药物或生物材料发展到药物与屏障材料结合的复合式药膜,加之中药以及分子生物学产品的发展,使它们不但抑制了外源性愈合,还促进了内源性愈合.防治方法也由简单的手术处理发展到全程的立体综合治疗,以期望达到理想的最佳效果.结论:尽管肌腱修复的生物材料研究在某些方面取得了一些突破性进展,但在很多方面仍需进一步实验探讨.     

踝关节内侧韧带损伤肌腱重建的三维有限元分析

背景：踝关节内侧三角韧带损伤的重建方法很多,但是目前还没有研究对这些方法进行对比。目的：三维有限元法对比Wiltberger、Deland、Kitaoka和Hintermann4种修复方法重建踝关节内侧韧带损伤肌腱后的效果。方法：建立踝关节三维有限元模型,模型中包括踝周的6块骨性结构、软骨和主要韧带。对模型进行验证试验后,在其基础上建立三角韧带损伤、Wiltberger、Deland、Kitaoka和Hintermann重建模型。在踝关节不同屈曲角度上对模型施加外翻及外旋应力,比较重建后的踝关节生物力学。结果与结论：4种重建方法均不能使踝关节生物力学完全恢复正常,其中Kitaoka法在恢复踝关节外旋稳定性上最有效,Deland法在恢复踝关节外翻稳定性上最有效。提示4种内侧韧带肌腱重建术式中,Kitaoka和Deland法较其他方法能够相对有效的恢复踝关节旋转稳定性。     

医用生物材料在肌腱损伤后粘连修复中的应用

背景：选用何种生物材料预防肌腱粘连,是目前医学界研究的热点。目的：总结近年生物材料在肌腱损伤术后粘连修复中的应用现状。方法：由作者应用计算机检索1999-01/2009-10维普数据库,选择生物材料修复肌腱损伤术后粘连的有关文章,共入选相关文献30篇。结果与结论：几丁糖具有良好的生物学特性,是一种无毒、无刺激性、无抗原性、组织相容性良好、在体内可降解吸收的新型医用生物材料,具有显著预防肌腱粘连作用。医用生物蛋白胶具有优良的止血与封闭作用、良好的生物相容性、生物降解功能,一定的杀菌作用,可减少和控制创伤炎症反应。大量临床研究及动物实验研究显示医用透明质酸钠、明胶海绵、糜蛋白酶等均具有防止术后组织粘连的作用。     

医用生物材料在肌腱损伤后粘连修复中的应用

背景:选用何种生物材料预防肌腱粘连,是目前医学界研究的热点.目的:总结近年生物材料在肌腱损伤术后粘连修复中的应用现状.方法:由作者应用计算机检索1999-01/2009-10 维普数据库,选择生物材料修复肌腱损伤术后粘连的有关文章,共入选相关文献30 篇.结果与结论:几丁糖具有良好的生物学特性,是一种无毒、无刺激性、无抗原性、组织相容性良好、在体内可降解吸收的新型医用生物材料,具有显著预防肌腱粘连作用.医用生物蛋白胶具有优良的止血与封闭作用、良好的生物相容性、生物降解功能,一定的杀菌作用,可减少和控制创伤炎症反应.大量临床研究及动物实验研究显示医用透明质酸钠、明胶海绵、糜蛋白酶等均具有防止术后组织粘连的作用.     

踝关节内侧韧带损伤肌腱重建的三维有限元分析☆

背景:踝关节内侧三角韧带损伤的重建方法很多,但是目前还没有研究对这些方法进行对比.目的:三维有限元法对比Wiltberger、Deland、Kitaoka和Hintermann 4种修复方法重建踝关节内侧韧带损伤肌腱后的效果.方法:建立踝关节三维有限元模型,模型中包括踝周的6块骨性结构、软骨和主要韧带.对模型进行验证试验后,在其基础上建立三角韧带损伤、Wiltberger、Deland、Kitaoka和Hintermann重建模型.在踝关节不同屈曲角度上对模型施加外翻及外旋应力,比较重建后的踝关节生物力学.结果与结论:4种重建方法均不能使踝关节生物力学完全恢复正常,其中Kitaoka法在恢复踝关节外旋稳定性上最有效, Deland法在恢复踝关节外翻稳定性上最有效.提示4种内侧韧带肌腱重建术式中,Kitaoka和Deland法较其他方法能够相对有效的恢复踝关节旋转稳定性.     

云南白药外敷治疗踝关节损伤

治疗方法:取云南白药4～8g,以酒精或正骨水将其调成糊状涂在患处,上盖纱布4～6层.初次敷药后保留7天,药糊干固可喷酒使其湿润,以保持药效的渗透作用.轻症者无须再换药,韧带部分断裂及单踝稳定性骨折者需7天换药一次,共用药2～3次即可.     

Syndesmosis injuries of the ankle

Ankle syndesmosis injuries are relatively frequent in sports, especially skiing, ice hockey, and soccer, accounting for 1 %–18 % of all ankle sprains. The evolution is unpredictable: When missed, repeated episodes of ankle instability may predispose to early degenerative changes, and frank osteoarthritis may ensue. Diagnosis is clinical and radiological, but arthroscopy may provide a definitive response, allowing one to address secondary injuries to bone and cartilage. Obvious diastasis needs to be reduced and fixed operatively, whereas less severe injuries are controversial. Nonoperative treatment may be beneficial, but it entails long rehabilitation. In professional athletes, more aggressive surgical treatment is warranted.     

Foot and ankle injuries in dance

Although dancers develop overuse injuries common in other athletes, they are also susceptible to unique injuries. This article reviews common foot and ankle problems seen in dancers and provides some basic diagnosis and treatment strategies.     

Effects of repeated ankle stretching on calf muscle-tendon and ankle biomechanical properties in stroke survivors

Background

The objective of this study was to investigate changes in active and passive biomechanical properties of the calf muscle–tendon unit induced by controlled ankle stretching in stroke survivors.

Methods

Ten stroke survivors with ankle spasticity/contracture and ten healthy control subjects received intervention of 60-min ankle stretching. Joint biomechanical properties including resistance torque, stiffness and index of hysteresis were evaluated pre- and post-intervention. Achilles tendon length was measured using ultrasonography. The force output of the triceps surae muscles was characterized via the torque–angle relationship, by stimulating the calf muscles at a controlled intensity across different ankle positions.

Findings

Compared to healthy controls, the ankle position corresponding to the peak torque of the stroke survivors was shifted towards plantar flexion (P < 0.001). Stroke survivors showed significantly higher resistance torques and joint stiffness (P < 0.05), and these higher resistances were reduced significantly after the stretching intervention, especially in dorsiflexion (P = 0.013). Stretching significantly improved the force output of the impaired calf muscles in stroke survivors under matched stimulations (P < 0.05). Ankle range of motion was also increased by stretching (P < 0.001).

Interpretation

At the joint level, repeated stretching loosened the ankle joint with increased passive joint range of motion and decreased joint stiffness. At the muscle–tendon level, repeated stretching improved calf muscle force output, which might be associated with decreased muscle fascicle stiffness, increased fascicle length and shortening of the Achilles tendon. The study provided evidence of improvement in muscle tendon properties through stretching intervention.     

MR imaging of ankle inversion injuries

Ankle inversions are common in the general population and in athletes. Multiple concurrent injuries are a common result of an ankle-inversion injury. Syndesmosis injury, lateral ankle ligament tears, peroneal retinaculum or tendon injury, osteochondral lesion, or fracture may occur. Chronic pain or instability may result from one or more of these injuries. MR imaging provides superior soft tissue resolution, high sensitivity for occult fractures, and the ability to image the articular cartilage and ankle ligaments directly. This article discusses the MR imaging evaluation of acute and chronic ankle inversion injuries.     

Magnetic resonance imaging of ankle injuries

Stress placed on the ankle from sport activity predisposes it to a variety of injuries. MRI, with its multiplanar capability and excellent soft tissue contrast, is uniquely suited for examining the complex anatomy of the ankle. It is the procedure of choice for imaging suspected tendon and cartilage damage. It is also highly sensitive in detecting radiographically occult bone injuries. This review first addresses technical factors important in generating high-resolution images that are crucial for accurate diagnosis in this area. Pathogenesis and MRI appearance of commonly encountered sport-related soft tissue and bone injuries around the ankle are presented and discussed.     

Leg, ankle, and foot injuries

The emergency provider (EP) must be aware of the anatomy of the leg, ankle, and foot. The varied presentation of common injuries must be recognized as well as the unique presentations of uncommon injuries. The astute EP must rely on a focused history and a precise examination to avoid the pitfalls and missed injuries from an over-reliance on radiographic studies. In some cases, emergent orthopedic consultation is required. Potential complications associated with these injuries must be anticipated and avoided if possible.