Proximal Femoral Shortening after Operation with Compression Hip Screws for Intertrochanteric Fracture in Patients under the Age of 60 Years

PURPOSE We aimed to quantify proximal femoral shortening after operation with compression hip screws for intertrochanteric fracture in patients under the age of 60 years. MATERIALS AND METHODS We followed 37 consecutive patients with intertrochanteric fractures treated with compression hip screws from March 2005 to February 2014. We designated the aspect of the fracture, a defect of the postero-medial wall, a defect of the lateral wall, and the degree of reduction as four potentially important factors we assumed would strongly affect proximal femoral shortening. We quantified proximal femoral shortening and compared the effects of above factors. We divided femoral shortening into two plane vectors; femoral offset in the horizontal plane and leg length discrepancy in the vertical plane. We measured shortening separately during two periods: during operation and after weight bearing (called dynamic compression). RESULTS After bone union, the average femoral offset shortening was 5.45 mm. Patient groups with anatomic reduction and intact postero-medial wall showed lower femoral offset shortening than the respective opposite groups. As to functional score using modified Harris hip score, low femoral offset shortening group showed more 2.35 scores than high groups. None of the factors significantly affected leg length shortening. CONCLUSION We found that a stable medial buttress is involved in lower femoral offset shortening. Thus, surgeons need to attempt to recover the defect of the medial wall and to reduce anatomically when operating intertrochanteric fractures with compression hip screws.