Radiological Evaluation of Effectiveness of PCCP Fixation for Femoral Neck Fracture: Med-term Effectiveness in a Retrospective Multicenter

Background It has been reported in the literature that the complication rate of percutaneous compression plate (PCCP) is the lowest among the new internal fixators for the treatment of femoral neck fracture (FNS). However, no multicenter studies of PCCP for FNS have been reported. This study aimed to evaluate the med-term effectiveness of PCCP in a multicenter mainly through radiology. Methods 265 patients with FNF treated with PCCP fixation in our five hospitals between January 2011 and December 2020 were retrospectively analyzed. 140 men and 125 women; aged 19-79 (mean 51.6）years. The follow-up time was 2-5 years (mean 3.1). Radiological evaluation of the therapeutic effect was the main outcome, and the function was the secondary outcome. Results One case of screw cutting out, 3 cases of screw back out, 25 cases of neck shortening, 2 cases of nonunion, 8 cases of delayed healing, and 29 cases of avascular necrosis (AVN). Bivariate correlation showed that shortening healing was correlated with age, Singh index, and Garden alignment index, poor healing was correlated with garden alignment index, and AVN was correlated with Pauwels and Garden classifications and operation timing. Further pairwise comparison analysis showed that age of > 65 and Singh index IV were dangerous factors for neck shortening, and the operation timing > 3 days, Pauwels II and III, and Garden III and IV were dangerous factors for AVN. The excellent and good rate of function in 198 patients who were readmitted for internal fixator removal or other surgery was 90.9%. Conclusion PCCP for FNS has satisfactory med-term efficacy with a low complication rate. The main complication is AVN, which is prone to occur in patients with displaced Pauwels II or III FNF and operation timing > 3 days. Another main complication is shortening healing, which is prone to occur in patients with an age of > 65 and Singh index IV.