骨和骨愈合生物学.pptVIP

* 延迟愈合是骨折未能在平均愈合时间内愈合。这种并发症是骨折愈合过程缓慢的表现，但并不意味着会导致畸形或者愈合失败。这些情况下，愈合过程需要额外附加的时间，但最终骨是会愈合的 畸形愈合是骨折愈合，但是伴随着骨折区的异常角度和畸形。畸形愈合可在骨折愈合的任何阶段被检测到，在治疗过程中或治疗后。在骨折愈合完成前，骨折部位的过度畸形可通过对线复位和重新固定来进行不同程度的修正。如果骨折愈合接近完成，对线复位就必须在外科手术下完成。一些畸形愈合不值得冒着增加延迟愈合和骨不连的风险去反复的尝试对线。 骨不连指的是在6到9个月以后仍未能获得骨折区完全、坚强与稳定的愈合。骨不连的特点是在骨折部位有过多的活动性，成为一个假关节 血管化，在愈合过程中，再血管化是极其重要的。如果骨折碎片有良好的血供，碎片可以成活，没有其他并发症的情况下，骨折就可以愈合。下肢远端骨折的血液循环损失或减少是最严重的并发症之一 血液循环中断可引起： 骨折端软组织肿胀 骨折端大血管创伤性断开 如果一个碎片失去血供，碎片坏死，存活的碎片会联合或融合，坏死的碎片会和存活的碎片在某一个点联合而复活或者融合成一个死骨。融合是很缓慢的，需要骨折线的绝对稳定固定。如果两个碎片都无血供，骨的愈合在再血管化前就不会发生。 Delayed union is failure of the fracture to consolidate within the time usually required for union. This complication is indicative of retardation of the healing process but does not mean resulting deformity or failure of union. The healing process in these cases requires additional time, but solidarity of the bone eventually occurs. Mal-union is indicative of union of the fracture but with an increased degree of angulation or deformity at the fracture site. Mal-union may be detected at any stage throughout the healing process or after it is complete. Before completion of the healing process, excessive deformity at the fracture site may be corrected to varying degrees through realignment and reimmobilization. If the healing process is near completion, correction of the alignment must be accomplished by surgical intervention. Some degrees of mal-union are not worth the risk of repeated attempts to correct the alignment because of increased incidence of delayed union or malunion. Non-union is the failure of a fracture site to consolidate and produce a complete, firm, and stable union after 6 to 9 months. Non-union is characterized by excessive mobility at the fracture site, creating a false joint or pseudarthrosis. VASCULARIZATION During the time of healing, revascularization is extremely important. If both fracture fragments have a good blood supply and are therefore alive, the fracture will heal, provided there are no other complicatio