Session IX - Femur
Sat, 10/9/04 Femur, Paper #53, 4:35 pm
Femoral Nailing in the Obese Patient: The Agony of Antegrade Nailing
Purpose: Obese patients represent a growing proportion of our population. Treatment of fractures in this patient population presents unique challenges that must be faced ever more commonly. Retrograde femoral nailing has evolved as a rational treatment method because of difficulties with antegrade nailing in these patients. However, there is little data to document the problems with antegrade nailing in such patients. Furthermore, any differences in injury characteristics and clinical outcomes in obese patients remain unstudied. The purpose of this investigation was to compare obese to non-obese patients with regard to femoral shaft fracture characteristics, results of antegrade vs. retrograde femoral nailing, and clinical outcomes.
Methods: A total of 112 consecutive patients treated with intramedullary nailing for a femoral shaft fracture (OTA 32) were included in this prospective, multicenter, Institutional Review Board-approved study. There were 21 patients with a Body Mass Index (BMI) of more than 30 in the obese group (OG), and 91 with a BMI <30 in the lean group (LG). Intraoperative data were collected for all patients. Twelve patients were lost to follow-up, and the remaining subjects were observed at least to healing or development of a delayed union or nonunion (average, 10 months).
Results: Open fractures occurred less commonly in the OG (11%) than in the LG (22%), (P <0.05). The distribution of fracture patterns (OTA) was similar between the two groups (OG: 10, 32A; 6, 32B; 5, 32C; LG: 38, 32A; 31, 32B; 22, 32C) (P >0.05). Antegrade nailing in the OG was associated with increased average operative time (96 minutes) compared with antegrade nailing in the LG (68 minutes), retrograde nailing in the OG (61 minutes), and retrograde nailing in the LG (60 minutes), (P <0.05). There was no difference in the operative time between the OG and LG for retrograde nail insertion (P >0.05). Similarly, the average radiation exposure was greater in the antegrade OG (196 seconds) than in the antegrade LG (130 seconds), the retrograde OG (64 seconds), and the retrograde LG (83 seconds) (P <0.05). There was no difference in radiation exposure between the retrograde OG and the retrograde LG (P >0.05). Healing complications occurred in 10% of the OG patients (two delayed unions) and in 12% of the LG patients (two nonunions, nine delayed unions). There was one superficial infection in one patient from the OG. Functional outcome, as determined by the Lower Extremity Measure (LEM), showed similar initial decline from baseline and similar subsequent improvement over time.
Conclusions: Antegrade femoral nailing in obese patients is associated with significantly increased operative time and radiation exposure compared with both antegrade nailing in non-obese patients and retrograde nailing in any patient. Obese patients are less likely to have an open femur fracture than non-obese patients but can be expected to have similar healing and complication rates and similar functional recovery.