Shortening And Varus Collapse Of Femoral Neck Fractures In Young Patients (<55 Years): Percutaneous Cannulated Screws Vs. Dynamic Hip Screw

Abstract

Background: The treatment of femoral neck fractures in younger patients is controversial. The objective of this study is to compare varus collapse and shortening of the femoral neck in young patients (<55 years) with femoral neck fracture treated with three percutaneous cannulated screws (PCS) or with open reduction and internal fixation (ORIF) using a dynamic hip screw (DHS).

Methods: In a university hospital 66 consecutive patients with a femoral neck fracture were evaluated in a prospective way. Inclusion criteria included every femoral neck fracture aged < 55 years old attended at our department during the study period and treated by bone fixation (ORIF with a DHS or with three PCS). Fractures were classified according to Orthopedic Trauma Association (OTA), Garden and Pauwels classifications. We divided the degree of shortening into two groups: moderate (< 5 mm) or severe (> 5 mm), and the degree of varus collapse into two groups: moderate (< 7°) or severe (> 7°) with relation to the unfractured hip. Euroquol-5D (EQ5D) questionnaires were employed to evaluate clinical results.

Results: Mean age was 44.1 years (range, 22-55) and mean follow-up 3.2 years (range, 2-5). Thirty-seven fractures were treated with three PCS and twenty nine with ORIF using a DHS. There were 34 undisplaced fractures and 32 displaced fractures. 21 fractures showed comminution of the medial cortex and 14 of the posterior cortex. The rate of avascular necrosis (AVN) was 9.1% (6 cases). There were no cases of nonunion. Mean femoral neck shortening was 6.2 mm (range, 1-13) and mean varus collapse was 8.1° (range, 1-15°). Patients following AVN or with severe shortening and varus collapse presented lower quality of life scores.

Conclusion: We found a higher degree of varus collapse and shortening in patients treated with PCS.