Proximal femoral nail antirotation (PFN-ATM) fixation of extra-capsular proximal femoral fractures in the elderly: retrospective study in 102 patients.

BACKGROUND

The best surgical strategy for extra-capsular proximal femoral fractures (PFFs) is controversial in the elderly. Poor bone quality and neck screw instability can adversely affect the results with currently available fixation devices, which predominantly consist in dynamic hip screw-plates and proximal reconstruction nails.

HYPOTHESIS

The helical blade of the proximal femoral nail antirotation (PFN-A™) achieves better cancellous bone compaction in the femoral neck, thereby decreasing the risk of secondary displacement.

MATERIALS AND METHODS

We retrospectively reviewed consecutive cases of PFN-A™ fixation performed between 2006 and 2008 in 102 patients (75 females and 27 males) with a mean age of 84.9 ± 9.5 years (range, 70-100 years). Functional outcomes were assessed using the Parker Mobility Score.

RESULTS

Mean follow-up in the 102 patients was 21.3 ± 17.5 months (4-51 months). Fracture distribution in the AO classification scheme was A1, n=45; A2, n=41; and A3, n=16. At last follow-up, Parker Mobility Score values in the 65 survivors were 0-3, n=35; 4-6, n=11; and 7-9, n=19. Fracture union was consistently achieved, after a mean of 10.3 ± 3 weeks. Blade back-out allowed by the device design occurred in 16 (15.7%) patients but caused pain due to screw impingement on the fascia lata in only five patients (of whom two underwent reoperation). Cephalic blade cut-out was noted in three (2.9%) patients, of whom one required reoperation because of acetabular penetration. Two hardware-related fractures were recorded.

DISCUSSION

The new PFN-A™ device ensures reliable fixation with low mechanical complication rates. Although our data do not constitute proof that a helical blade is superior over a neck screw, they suggest a decreased rate of construct failure and may serve as a basis for a comparative study.