Factors Associated with Femoral Neck Shortening After Closed or Open Reduction and Screw Fixation

Purpose This study aimed to evaluate the incidence of femoral neck shortening (FNS) after the treatment of displaced and non-displaced femoral neck fractures with closed or open reduction internal fixation, and determine the independent factors associated with this condition. Method The study included 81 patients who underwent internal fixation by closed or open reduction with multiple screws between 2013 and 2018 due to femoral neck fracture (FNF) and were followed up for at least 1 year. Patients were divided into two groups as with and without FNS. The patient, fracture, and surgical parameters compared between the two groups, and the factors affecting development of FNS were investigated. Results Internal fixation was applied by closed reduction in 56 patients (69.1%) and open in 25 (30.9%). FNS was detected in 41 patients (50.6%), with the mean shortening 6.3 ± 6.4 mm. Fracture union achieved in 72 patients (89%). The mean time to fracture union was 4.3 ± 2.3 months. No statistically significant relationship found between FNS and the parameters of gender, age, smoking, reduction type, number, type and orientation of screws, Singh index, and Garden fix index ( p > 0.05). However, there was significant difference between two groups regarding energy of the fracture, fragmentation, coronal angulation, Garden type, and fixation with medial buttress plate ( p < 0.05) Conclusion FNS is an expected condition in FNF fixed by screws. Patients with high-energy traumas and advanced Garden types are more likely to have FNS. The use of medial plate may be effective in preventing FNS.