Effects of noradrenaline on blood supply of femoral head in dogs

AIM: To observe the changes of the hip in means of injecting 2‰ noradrenaline (NA) into the hip joint cavity and study the pathogenesis of transient sy-novitis of hip. METHODS: Forty 2-3 months old dogs were divided into 10 groups, and 2‰ NA was injected into the hip joint. 99mTC-MDP triphasic imaging was used to observe the local blood supply of femoral head, intra-articular pressure was determined, and patholoyical changes were observed to understand the natural course of the disease process. RESULTS: Injecting 2‰ noradrenaline resulted in transient contraction of blood vessels in femoral head and after 3 hours blood vessels begun to expand, exudation of hip joint caused an increase of pres-sure in hip joint. This process continued for 2 weeks. There was no necrosis of synovium and femoral head. The whole process resembled transient synovitis of hip in the clinical manifestation. CONCLUSION: Injecting 2‰ noradrenaline results in extension and congestion of blood vessels. An increase of pressure in hip joint causes transient ischemia in femoral head. The whole process resembles transient synovitis of hip in the clinical manifestation . Noradrenaline may play an important role in the pathogenesis of transient synovitis of hip.