术后可控制性微动锻炼与骨折愈合关系的研究进展

骨折是临床常见的一种疾病，其愈合过程复杂且与多种因素有关，对近年来骨折手术治疗后患者行可控制性微动锻炼与骨折愈合的关系进行综述，旨在探索微动促进骨折愈合的机制，提高患者生活质量。     

微动对骨折愈合影响的研究进展

微动对骨折愈合影响的研究进展张先龙曹炳芳骨折愈合是一个极其复杂的生物学修复过程，而且受到许多因素的影响。如何促进骨折愈合一直是骨科领域的研究热点。随着人们对骨折愈合研究的深入，对骨折的治疗也已进入了分子生物学时代，传统的骨折愈合理论也正在受到冲击。近...     

微动与骨折愈合

骨折愈合是一个非常复杂的过程，受很多因素的影响，其中力学环境的重要作用已为大家所共识。本文重点探讨了影响骨折端力学环境的众多因素中微动和微动的不同参数对骨折愈合的影响。     

微动应力与骨折间接愈合

骨折断端存在相对移动时,骨折以间接愈合的方式连接。微动应力能促进骨折的愈合,但程度与应力的方向及强度有关。机械应力对成骨细胞的生物刺激效应是促进骨痂形成的重要因素之一。应力使骨内发生应变,增加胰岛素样生长因子的分泌,促进骨形成。不过,骨折愈合不同阶段所需应力的相关参数尚未确立,其确切的细胞学机制与分子生物学机制仍不清楚。     

转化生长因子β与骨折愈合

转化生长因子β(ｔｒａｎｓｆｏｒｍｉｎｇｇｒｏｗｔｈｆａｃｔｏｒｂｅｔａ,ＴＧＦβ)是肌肉骨骼与免疫系统中一组功能广泛的多肽生长因子,在骨的发生、发展和修复过程中有重要作用。近年来,许多学者对ＴＧＦβ的结构、功能及其与骨折愈合的关系做了深入的研究。1　ＴＧＦβ的生化特点Ｄｅｌａｒｏ和Ｔｏｄａｒ〔1〕于1978年首先发现病毒转化的细胞能分泌一种具有使正常大鼠肾成纤维细胞表型发生转化能力的因子,并命名为ＴＧＦβ。它是由112个氨基酸组成的多肽亚单位,并通过二硫键相连的二聚体,分子量为23ｋｕ。成熟的ＴＧＦβ包括5种ＴＧ…     

可控性应力与微动对骨折愈合影响的组织学研究

目的 探讨骨折端在不同轴向应力作用下,不同骨折愈合时期所需轴向应力的适宜力值. 方法 32只青山羊均行股骨干中段横行截骨制作骨折模型,按骨折端施加实验动物自身体质量的0倍(对照组)、1/6(A组)、1/3(B组)、1/2(C组)应力分为4组,每组8只.术后4、8周分批处死,每次每组处死4只,行大体观察和组织学观察,测量骨折端骨外膜骨痂面积. 结果 对照组有1只动物骨折端发生成角畸形,实验A、B、C组分别有1、2、4只动物骨折端发生成角畸形.术后4周,对照组、A、B、C组骨折端骨外膜骨痂面积平均值分别为(1.15±0.34)、(1.86±0.28)、(2.18±0.36)、(1.99±0.33)cm~2,A、B、C组分别与对照组比较,骨折端骨痂生成多,骨外膜骨痂面积差异有统计学意义(P<0.05).术后8周,沿轴向排列骨外膜骨痂中骨性骨痂多、致密,皮质骨松化明显;对照组、A、B、C组骨折端骨外膜骨痂面积平均值分别为(1.38±0.31)、(2.09±0.23)、(2.69±0.28)、(2.71±0.31)cm~2,A、B、C组分别与对照组比较,B、C组分别与A组比较,差异均有统计学意义(P<0.05). 结论 骨折端施加轴向应力时能促进骨折端骨痂生长,较大的应力强度能更好地促进骨折端骨痂生长,但同时会造成骨折愈合成角畸形发生率增高.骨折端施加自身体质量的1/3应力时骨折端成角畸形发生率较低,最适宜促进骨折端骨痂生长.     

低频可控性微动影响长骨骨折愈合的实验研究

目的应用可控性微动外固定支架研究骨折端低频微动对骨痂增殖和骨折愈合的影响。方法绵羊39只,双侧胫骨中段横行截骨,间隙2mm,用连有微动装置的单边外固定支架固定。术后10d,随机选择一侧肢体进行微动,按不同的微动频率分为3组:A组0.5Hz,B组1Hz,C组5Hz;幅度为0.25mm,4周结束(30min/d)。另一侧肢体不微动,为对照组。分别于术后4、6、9周切取标本进行大体观察、X线检查、组织学检测及生物力学测试。结果大体与X线检查显示各实验组均有大量的骨痂生成,4周末达高峰;组织学检测显示微动组骨痂软骨内骨化与类骨质形成的速率在6周最为明显,均快于对照组,以B组形成速率最快。9周末生物力学测试微动组弯曲刚度均强于对照组,以B组的力学强度最大。结论骨折端低频微动在骨折愈合早期均能有效地促进骨痂生长,加速骨痂的矿化,以1Hz频率效果最佳。     

针灸促进骨折愈合机制的研究进展

针灸对促进骨折愈合有着显著的疗效,具有疏通经络、调和气血、消肿散淤等作用,然而其机制仍然未完全阐明。随着研究的不断深入,近年来发现针灸促进骨折愈合的机制涉及调节细胞生长因子表达水平,激活WNT/β-catenin等信号通路,改善局部的血液循环,影响骨中矿物元素的含量,调节内分泌系统,促进骨细胞的分化与增殖,促进成骨细胞的增生与激活和影响骨细胞凋亡等多方面。针灸促进骨折愈合的机制非常复杂,尚处于动物实验和细胞水平,本文对以上研究进展进行综述总结。     

中药对小鼠骨折后血管重建与骨折愈合方式关系的影响

目的 探讨中药对小鼠骨折后血管重建与骨折愈合方式关系的影响。方法 昆明种小鼠50只，制作闭合性胫腓骨骨折模型，随机分为两组，实验组口服中药，对照组口服生理盐水。分别于术后第3、7、15、21、28天处死动物。腹主动脉墨汁灌注，制成石蜡切片。HE染色，光镜观察。结果 实验组骨折部位血管的增生、扩张程度高于对照组。软骨内成骨占整个骨痂的比例少于对照组。实验组较对照组约提前1周愈合。结论 中药通过促进骨折部位血管增生、扩张，加速软骨骨痂改建，减少软骨内成骨，增加膜内成骨的比例，促进骨折的愈合。     

胶原蛋白与骨折愈合的关系

胶原蛋白在骨和体内其他组织中的分布到目前为止人们已经发现了19种基因编码不同的胶原蛋白,各种类型的胶原按其发现顺序用罗马数字标记,按照它们的结构特点的不同又可分组[1,2].     

中西医结合治疗骨折微循环研究

本项研究采用大耳白兔为实验动物，采用外骨膜广泛剥离、部分肌肉切除的桡骨骨折的动物模型，采用自身对照法，分成对照组、实验组。对照组不包括软组织损伤及骨膜广泛剥离的骨折模型。利用组织学、电镜及血管灌注等方法对骨折愈合微循环变化进行了观察。并将软组织损伤对骨折愈合过程中的微循环及超微结构的变化进行了分析。术后１～８周随机分批处死动物，标本观察。实验结果显示：１．１至４周毛细血管代偿性扩张较对照组差，新生毛细血管管腔狭窄、闭塞。５周后骨折处微循环开始接近正常。２．骨皮质外侧四分之一的骨细胞变性坏死比较明显。３．形成骨痂的成骨细胞活性明显降低、胶原合成不良、骨折愈合相对迟缓。此项研究显示软组织损伤及骨外膜剥离与骨折愈合过程中的微循环改变具有直接关系。软组织损伤及骨外膜剥离可加重骨折断端的缺血，导致骨折愈合过程相对迟缓。     

细微运动对长骨干骨折愈合的作用——动物实验系列研究初步总结

新西兰兔108只,造成股骨中段骨折用髓针内固定86只;胫骨中段骨折用钢板螺钉内固定22只,随机分成三组。A组用脉冲电流刺激仪刺激肌肉收缩,B组用脉冲机械振动仪振动骨折段,C组是对照组。实验结果显示:骨折肢体的血流,骨痂的钙和镁元素,GH、B_2m、AKP和低分子蛋白定量,以及骨折愈合的刚度和强度,实验组A、B均较对照组高,骨折愈合快。临床启示:骨折内固定后接受细微运动而产生骨折段内应变,能促进骨折愈合。     

Recent Advances Toward the Clinical Application of PTH (1-34) in Fracture Healing

PTH 1-34, an active form of parathyroid hormone, has been shown to enhance osteoblastic bone formation when administered as a daily subcutaneous injection. The effect of the intermittent administration of PTH (1-34) is an uncoupling of bone turnover with an increase in bone mass and density and decrease in risk of vertebral and nonvertebral fractures. While PTH (1-34) has been used clinically to increase bone mass and reduce fracture risk in postmenopausal women with osteoporosis, there is increasing evidence that PTH (1-34) may promote fracture healing. Animal studies have demonstrated accelerated callus formation with enhanced remodeling and biomechanical properties of the healing fracture. Given these effects, PTH (1-34) will likely be used clinically to enhance fracture union in poor healing situations such as osteoporosis and recalcitrant nonunions.     

Fracture Healing: A Concept of Competing Healing Factors

In the discussion concerning the theory of the healing of shaft fractures the demand for absolute stability of the fracture has been a dominating factor. This cannot be an absolute prerequisite because fractures of the tibia or femur heal well even with continued weight-bearing and movement. the ingrowth of vessels is apparently not a crucial factor. It is evident, however, that fractures caused by direct violence with soft tissue damage heal more slowly than fractures caused by indirect violence, irrespective of the treatment. Soft tissue heals with fibrous scar; fractures heal by bone regeneration. the author postulates that the damaged tissue stimulates (possibly via molecular determinants) the structural genes of undifferentiated cells to produce mRNA and proteins for either fibrous tissue or bone formation. the rate of healing of the fracture is determined by the degree of bone damage in relation to soft tissue damage. in fractures with extensive soft tissue injury there occurs a competitive condition in the common haematoma, with a risk of delayed fracture healing due to the dominance of cells that are triggered off by fibrous tissue formation.     

Fracture Healing: A Concept of Competing Healing Factors

In the discussion concerning the theory of the healing of shaft fractures the demand for absolute stability of the fracture has been a dominating factor. This cannot be an absolute prerequisite because fractures of the tibia or femur heal well even with continued weight-bearing and movement. the ingrowth of vessels is apparently not a crucial factor. It is evident, however, that fractures caused by direct violence with soft tissue damage heal more slowly than fractures caused by indirect violence, irrespective of the treatment. Soft tissue heals with fibrous scar; fractures heal by bone regeneration. the author postulates that the damaged tissue stimulates (possibly via molecular determinants) the structural genes of undifferentiated cells to produce mRNA and proteins for either fibrous tissue or bone formation. the rate of healing of the fracture is determined by the degree of bone damage in relation to soft tissue damage. in fractures with extensive soft tissue injury there occurs a competitive condition in the common haematoma, with a risk of delayed fracture healing due to the dominance of cells that are triggered off by fibrous tissue formation.     

The Role of the Immune Cells in Fracture Healing

Purpose of review

Bone fracture healing is a complex physiological process relying on numerous cell types and signals. Inflammatory factors secreted by immune cells help to control recruitment, proliferation, differentiation, and activation of hematopoietic and mesenchymal cells. Within this review we will discuss the functional role of immune cells as it pertains to bone fracture healing. In doing so, we will outline the cytokines secreted and their effects within the healing fracture callus.

Recent findings

Macrophages have been found to play an important role in fracture healing. These immune cells signal to other cells of the fracture callus, modulating bone healing.

Summary

Cytokines and cellular signals within fracture healing continue to be studied. The findings from this work have helped to reinforce the importance of osteoimmunity in bone fracture healing. Owing to these efforts, immunomodulation is emerging as a potential therapeutic target to improve bone fracture healing.

     

Assessment of Fracture Healing by Vibration

The wave signal from percussion of a bone (i.e. percussion-note) has been used to evaluate the extent of bony consolidation after fracture.

Forty-one cases with a fresh tibial fracture and eight cases of delayed union of the tibia were investigated. The medial malleolus of the tibia was struck with a tapper and the vibration signal was picked up at the medial region of the tibial tuberosity. The changes in the signal waveform of the percussion-note with time were investigated.

As healing proceeds, the signal waveform of the fractured bone approaches that of intact bone. In cases of delayed union, the character of the wave does not improve sufficiently with time. The authors are convinced that this is a promising new method for the early diagnosis of delayed union.