基于三维模拟动态分析健脾活骨方治疗早中期非创伤性股骨头坏死生物力学机理研究

Osteonecrosis of femoral head(ONFH) is a common and intractable diseases in clinics which is most frequently found in youth adult patients aged from 30 to 50. Previously, our research group apllied JianPiHuoGu Formula to manage early-to-middle stage ONFH cases and received favorable effects. The mechanism of this modality was proved related to suprrsion of osteoclastogenesis and its activation which gave birth to regeneration of bone trabeculae and bone mass increasement. However, due to the shortage of data involving restoring degree and speed of femoral head in terms of biomechanical capacity after bone mass augment, the duration of immobilization in clinical became a intractable for both physicians and patients. This study intends to adopt a method with dymamic three-dimiension simulating analysis to establish a three-dimension model. Thereafter, mechanecial load of verious kinds of acitivities in daily life will be loaded for different stages in therapy with help of computer aided design softwares to observe the stress distribution and collapse conditon of femoral head and to discuss risk level of collapse, in other word, to prodict wether the femoral head will collapse. In addtition, to investigate the repairing ability of JianPiHuoGu Formula on early-to-middle stage ONFH patients as to better understand the biomechanical mechanism of Chinese Medicine on this medical condition and eventually to o provide a fairly objective evidences for doctors to guide patients rehabilitate as well as for sufferers to recuperate more efficiently.

股骨头坏死是骨科常见疑难病，好发于30-50岁的青壮年，前期课题组采用健脾活骨方治疗早中期非创伤性股骨头坏死取得较为满意效果，其作用机制与抑制破骨细胞的生成和活化，从而促进骨小梁的修复、增加骨量有关。但是，由于缺乏对其骨量增加后力学承载程度、速度的研究，临床中制动的时限长短成为困扰医生和患者的难题。本项目采用三维模拟动态分析方法，建立股骨头坏死三维模型，分别运用日常中各种活动方式的力学载荷对治疗过程的不同阶段进行加载，再通过计算机软件进行分析，检测坏死区的应力分布情况及塌陷情况，探索引起坏死股骨头塌陷的危险程度，预测股骨头塌陷的危险性。然后通过动态力学承载探索健脾活骨方对早中期非创伤性股骨头坏死的骨修复的能力，更好地了解中医治疗早中期非创伤性股骨头坏死的生物力学机理，为临床医生指导患者的康复、使患者尽快恢复正常活动提供客观依据。

目的：通过探讨健脾活骨方治疗早中期非创伤性股骨头坏死的生物力学机理，探索引起坏死股骨头塌陷的危险程度，预测股骨头塌陷的危险性。方法：采用有限元分析方法，建立正常股骨头、未塌陷股骨头坏死及塌陷股骨头坏死三维模型，分别运用日常中各种活动方式的力学载荷对治疗过程的不同阶段进行加载，检测受力面及坏死区的应力分布及形变情况。通过优化力学仿真算法的骨骼密度-弹性模量测试实验得到更适用于中国人的骨骼强度的力学参数以及预测股骨头塌陷的力学参数。结果：正常股骨头表面应力分布均匀，股骨头内压应力延压力性骨小梁均匀分布在股骨头内，股骨近端内侧承受大部分压应力，而外侧仅承受少量压应力；未塌陷股骨头坏死股骨头表面应力较集中，股骨头内压应力分散于股骨头与股骨颈交界处，股骨颈外侧较正常股骨头应力明显增大，股骨近端内侧与外侧同时承受的压应力相当；塌陷股骨头坏死力学传导机制与未塌陷股骨头坏死相似，但应力集中现象较未塌陷股骨头坏死明显。塌陷股骨头坏死治疗前股骨头受力面及坏死区应力及形变均明显大于未塌陷股骨头坏死与正常股骨头，未塌陷股骨头坏死治疗后3个月与治疗后1年与治疗前比较，应力集中情况明显减轻，受力面与坏死区的等效应力与形变明显减小。塌陷股骨头坏死治疗后3个月与治疗前比较，应力集中情况未见明显改善，塌陷股骨头坏死治疗后3个月较治疗前比较，受力面与坏死区的等效应力与形变虽有减少，但相对于同期未塌陷股骨头坏死比较，受力面与坏死区的等效应力与形变较大。不同步态测试结果显示随着步态由正常行走到慢速跑步，再到快速跑步，其股骨头受力面及坏死区等效应力与形变随之增加。结论：塌陷股骨头坏死股骨头受力面及坏死区应力集中现象明显，治疗后应力集中情况虽有减轻但未得到明显改善，坏死骨骨小梁长期承受较大应力而引起塌陷。相对于塌陷股骨头坏死，未塌陷股骨头坏死受力面及坏死区应力集中现象较轻，且治疗后3个月及1年受力面及坏死区等效应力与形变均明显减少，说明坏死区骨质得到修复，承受应力较为均匀，应力集中情况得到改善。不同步态测试可以看出随着步态频率增加，坏死区所承受压力及位移值增加明显，股骨头塌陷的风险逐渐增大，尤其在快速跑步下，股骨头坏死塌陷风险更大，故治疗期间应尽量避免跑步等剧烈活动