[Strategies of closed reduction in treatment of femoral neck fracture using cannulated screw fixation].

Objective: To study intraoperative reduction strategy in treatment of femoral neck fracture using cannulated screw fixation and the relationship between excellent and good rate of reduction and postoperative effectiveness.

Methods: A retrospective analysis was made on the clinical data of 174 cases of femoral neck fracture treated between August 2005 and March 2015. There were 78 males and 96 females with an average age of 53.8 years (range, 23-75 years). The injury causes were falling in 85 cases, traffic accident in 61 cases, and falling from height in 28 cases. According to Garden typing, there were 35 cases of type I, 56 cases of type Ⅱ, 47 cases of type Ⅲ, and 36 cases of type Ⅳ. The time from injury to operation was 1-7 days (mean, 2.74 days). Based on reduction strategy, closed 3 hollow compression screws were used; evaluating standards for fracture reduction effect were also established. Harris score was used for effectiveness evaluation.

Results: All the cases received follow-up of 12-42 months (mean, 36.5 months). Bone healing was obtained in 152 cases at 6-12 months (mean, 9 months). Non-union and internal fixation failure occurred in 9 and 3 patients respectively, who underwent hemiarthroplasty; femoral head necrosis occurred in 6 patients after removing internal fixator at 15-26 months (mean, 18.5 months) after operation, who underwent total hip arthroplasty; 4 patients with non-union received vascular pedicle iliac flap transplantation. No other serious complications were observed. At last follow-up, the excellent and good rate of reduction was 94.29% for Garden type I, 91.07% for type Ⅱ, 87.23% for type Ⅲ, and 75.00% for type Ⅳ, with a total excellent and good rate of 87.36%; the excellent and good rate of Harris score was 97.14% for Garden type I, 78.57% for type Ⅱ, 68.09% for type Ⅲ, and 50.00% for type Ⅳ, with a total excellent and good rate of 73.56%.

Conclusions: To obtain high Harris score in fixation of femoral neck fractures by using hollow screws, surgeons not only need reasonable technology, but also follow correct and good reduction strategy and assessment,fracture complexity is inversely proportional to excellent and good rate of reduction. Higher excellent and good reduction rate of complexity fracture should be obtained as much as possible in order to achieve good prognosis.