Clinical Research On Epiphysis Changes In Avascular Necrosis Of Femur Head Between Pre- And Post-operation In The Development Dislocation Of Hip

Objective:To explore the pathogenesis of avascular necrosis (AVN)of femur head developed after treatment in development dislocation of hip(DDH)and to summarize the surgical treatment experience according to the epiphysis changes between pre- and post-operation. Methods:From 2002 to 2005, 16 patients with AVN of femur head secondary to DDH in our hospital were examined retrospectively. Based on radiography materials and biomechanical principles, analyses of anatomy, biomechanics and pathophysiology on acetabular and epiphysis of the femur head were made, and researches on the shape changes of femur head epiphysis were underwent. Thus the possible factors of AVN of femur head in DDH were detected and the surgical treatment experiences were summarized. Results:After surgery on 16 patients with iatrogenic AVN of femur head in DDH, according to the grading standard by Zhang and Dai the final results can be divided as excellent in 2case(12.5%),good in 6 cases(37.5%)and poor in 8(50%). Conclusion:Through clinical research we regard that there are multiple factors on AVN of femur head after the treatment of DDH, which can cause larger stress between the acetabular and the epiphysis of the femur head. The surgical treatments can relive the abnormal stress of the hip joint, regain the concentric containment in proper physiological status and facilitate the recovery and natural development of femur head epiphysis. There are always integrated reasons and each case has its trait, so special analysis should be carried out in order to make a clear treatment project and improve the clinical effects. If the patient is much younger, and the illness is slighter, early dignosis and early treatment as well as active exercises postoperativly can be made, the effect should be much better. On...