Relationship Between On Weight Bearing Time and Femoral Head Necrosis after Operation of Femoral Neck Fracture

Objective:To investigate the relationship between on weight bearing time and femoral head necrosis after operation of femoralneck fracture,and to provide theoretic basis for the proper exercise after operation.Methods:The 139 cases of femoral neck fracture were followed-up for 5～10 years after fixation operation.They were randomly divided into three groups according to their on weight bearing time after operation,on weight bearing time before 3 months(3-month-group) ,on weight bearing time between 3 and 6 months(3～6-monthgroup) ,on weight bearing time after 6 months(6-month-group) .The rate of femoral head necrosis was analyzed and compared in eachgroups.SPSS 11.0 Stat.software was used to analyze the results.Results:There were 43 femoral head necrosis occurred in all cases.Thetotal necrosis rate was 31%.17 cases in 3-month-group,13 cases in 3～6-month-group,13 cases in 6-month-group.The necrosis rate of 3-month-group was higher than other groups(P0.05) .The difference in the necrosis rate between 3～6-month-group and 6-month-group was not significant(P 0.05) .Conclusion:The rate of femoral head necrosis after the femoral neck fracture differs with the time of on weight beaing.Among them,unloaded activity between 3 and 6 months is the best way to restitution their function.