The Effect Of Different Movements On The Healing Of Articular Fracture And Cartilage Injury In Knee Joint

Objective(1)To study the effect about different modes of movements on healing of avulsion fracture of tibial inter-condylar eminence. (2)To study the effect about different modes of movement on shallowly/deeply damage of articular cartilage. (3)To observe ACL(anterior cruciate ligament) adherent area in tibial eminence in a morphological and anatomical way and explore some relative problems. Methods (l)Established 24 New Zealand white rabbit models for fixation of avulsion fracture of tibial inter-condylar eminence. All the animals were distributed in 3 different groups of movements equally. After imposing active movement, passive movement, gypsum fixation before free movement on the knee joints, then gauged P-ROM / X-ray / HE matoxylin and eosin examinations of the knee joint. (2)Established 24 New Zealand white rabbit models for shallowly/deeply damage of articular cartilage. After imposing active movement, passive movement, gypsum fixation before free movement on the knee joints, observed specimens after HE matoxylin and eosin under LM and collagen-fibers on the surface structure of articular cartilage under SEM. (3)Measured the dimensions, positions and profile of ACL adherent area in tibial eminence of 101 dry Chinese skeleton-specimens. Results (1)X-ray: Within the first 3 weeks, the healing level of active movement group was higher than that of passive movement group, however, there came a contrary result after the first 3 weeks. LM: During 2~5 weeks, the proliferous level of osteoid tissue in active movement group was higher than that of passive movement group; during 5~10 weeks this superiority of active movement group was inchmeal weaken. On the orther side, thelevel maturing of osteoid tissue in passive movement group was higher than that of active movement group. (2)LM & SEM: the proliferation of cartilage cells might be caused in passive movement group while shallowly damaged of articular cartilage. Moreover, passive movement seemed to provide better adaptation to make the damaged area recover more like the normal cartilage tissue in morphological structure. The other two groups came to the worse recover results on shallowly damage of articular cartilage, and the proliferous connective tissue appeared to invaded the remained cartilage tissue of the damaged area in the latest observational period, so as to accelerate the deterioration of the damaged articular cartilage. All the three movements came to nearly negative recover results in deeply damaged of articular cartilage, although aroused limited proliferation of cartilage cells that only provided serious insufficient recovery. (3)Width of adherent area was(9.38±1.67)mm, length (15.93±2.52)mm, the distance from front margin of ACL adherent area in tibial eminence to front margin of tibial eminence was (7.85±1.52)mm, the angle from axis of ACL adherent area to median sagittal axis was (21.54+4.61)°, the majority(57.4%) in the profile of ACL adherent area in tibial eminence was likely a inverted triangle. Conclusion (l)it bring unacceptable healing results of articular fracture in gypsum fixation condition . Active movement could held the proliferation of osteoid tissue in dynamic level, meanwhile passive movement could benefit the maturing of osteoid tissue. (2)Only the passive movement could probably arouse limited healing results to compensate the deficient area in sballowly damaged of articular cartilage. None of each group performed a satisfying result in deeply damaged of articular cartilage. (3)The stability of ACL against exterior lacerating forces under varied extreme motions is strengthened by the anatomical position of ACL adherent area in tibial eminence meanwhile ACL being lacerating may cause the increase rate of meniscus injures in knee joint. The irregular distribution of fibre within ACL adherent area in tibial eminence bring difficulties in locating the entrance of tibial channel in reconstruction of ACL by arthroscopic assisted "isometric point".