Does the functional outcome of unstable pertrochanteric fractures improve with proximal femoral nailing? A prospective study of its usage in 50 patients

Abstract

Background: Proximal Femoral Nail (PFN) provides tangible evidence for its usage in unstable pertrochanteric fractures. There are a veritable number of references which show that PFN by virtue of its intramedullary fixation reduces the tensile strain thereby mitigating implant failure. Ours is a prospective study done on 50 subjects to assess the outcome of PFN usage in unstable pertrochanteric fractures. Methodology: 50 patients with Jensen Michaelsen type III, IV, V intertrochanteric and reverse oblique fractures were included in the study. The reduction obtained intra operatively was assessed using the modified criteria of Baumgaertner. Follow up evaluations were done at 6, 12, 24 and 52 weeks thereafter. Clinical evaluation was done using the Mobility score of Parker and Palmer. Radiographic parameters like fracture union, screw slide and degree of varus collapse were also assessed. Statistical analysis was provided by Friedman test. Results: Jensen Michaelsen type IV was the most common pattern observed (44%). The mean pre-injury parker score was 8.4. Patients with reverse oblique fracture morphology, type V fractures and patients with osteoporosis were treated with Long PFN (19 cases). The mean operating time was 92 minutes (range 60 - 180), and the mean blood loss during the surgery was 145 ml (range 100ml - 320 ml). The reduction was good in 40 patients (80%) and acceptable in the rest. The average time taken for fracture union was 15 weeks. It was observed that patients reached their preoperative mobility score of Parker and Palmer by 6 months post-surgery which was statistically significant (χ2 = 217.642, p < .001). Discussion: Proximal Femoral Nailing is done through a minimally invasive approach not disturbing the fracture hematoma which is a vital in fracture consolidation. The biomechanics of intramedullary fixation in cases of destabilised medial cortex is optimised by medialization of the fulcrum point and resultant reduction of the bending moment with respect to proximal fixation. Fracture reduction was good in 80% cases and in 10 cases the reduction was acceptable with a mean varus malalignment of 13.2 degrees.The mean intraoperative blood loss of 145 ml in our series compares favourably with previously reported values in the literature. Most of the fractures in our series (66%) united by 12-14 weeks. The mean preoperative mobility score of Parker was 8.4, which was reached by patients on their 6th postoperative month (p & lt; 0.001). Each period showed statistically significant improvement over the previous period as evident from the rank total of the scores and the critical ratio.