To study the short-term effect on femoral head after removal of femoral neck internal fixation.

From March 2014 to January 2018, 68 cases of adult patients with femoral neck fracture received reduction and internal fixation of femoral neck fracture, Among them, 32 cases were treated with removal of femoral neck internal fixation after fracture healing. According to whether the internal fixation was removed, the patients were divided into the removal group(32 cases) and the retention group(36 cases). Two independent samples t test, chi square test, Fisher exact probability method and repeated measurement ANOVA were used to compare the general situation, fracture healing time, femoral head necrosis rate and Harris hip score between the two groups.

The follow-up time of the removal group was (31.7±6.8) months. At the last follow-up, the healing rate of the removal group was 21.9%, the incidence of femoral head necrosis was 34.4%. Harris hip score of the removal group before the operation was (12±3); at the last follow-up, the Harris hip score was (84±20). The follow-up time of the retention group was (32.7±7.0)months. At the last follow-up, the incidence of femoral head necrosis of the retention group was 8.3%. The Harris hip score of the retention group before operation was (13±4), and (91± 14)at the last follow-up. The femoral head necrosis rate (t=7.027)and Harris hip score of the retention group(F=7.835) were better than the removal group (both P<0.05).

Because of the biomechanical changes, the healing rate of the nail path is low in a short time after the removal of the femoral neck internal fixation, which increases the incidence of femoral head necrosis and leads to the deterioration of hip joint function.