Surgical Factors Affecting the Union Rate of Complex Distal Femoral Fractures

Background:

Management of complex, comminuted distal femoral fractures present a challenge to orthopaedic surgeons. High rate of complications are associated with surgical management of such injuries especially in elderly patients. This study aims to review the outcome of surgical fixation of these complex injuries at our trauma unit, to identify correctable surgical factors associated with rate of union.

Methods:

Patients undergoing open reduction, internal fixation of distal femoral fractures at our Institute from 2008 to 2018 were included in the study. A retrospective analysis of patient factors, surgical parameters, complications and union rate was performed.

Results:

79 patients were included in the analysis with mean age of 73 years (range, 33-101 years). There were 11 male and 68 female patients. The mean time to surgery was 3 days (0-14 days). There were 58 native femur fractures and 21 periprosthetic fractures. All patients had fixation with locking plates with MIPO technique. Those patients (49/79) who had fixation performed with longer plates (>10 holes) and ‘flexible construct’ achieved 100% union rate. However, there were 3(10%) non-unions in patients where fracture fixation was performed with ‘stiff construct’ (p=0.05). These three patients eventually healed with revision surgery using longer plates and flexible construct.

Conclusion:

Longer plate with ‘end to end’ fixation of femur in comminuted distal femur fractures employing flexible construct are related to improved outcomes. Stiff construct and short plates may lead to non-union in such complex injuries. Longer plates and ‘flexible constructs’ are recommended to fix comminuted distal femoral fractures to increase the union rate.