Expandable Proximal Femoral Nail versus Gamma Proximal Femoral Nail for the treatment of hip reverse oblique fractures.

ABSTRACT

BACKGROUND: Reverse oblique intertrochanteric fractures are classified by the AO/OTA as 31A3 and account for 2-23% of all trochanteric fractures. The Gamma 3-Proximal Femoral Nail (GPFN) and the Expendable Proximal Femoral Nail (EPFN) are among the various devises used to treat this fracture. The aim of this study was to compare outcomes and complication rates in patients with AO/OTA 31A1-3 fractures, treated by either a GPFN or an EPFN. PATIENTS AND METHODS: A total of 67 patients (40 in the GPFN group and 27 in the EPFN group, average age 78.8 years) were treated in our institution between July 2008 and February 2016. Data on postoperative radiological variables, including peg location and tip-apex distance (TAD), as well as orthopedic complications, such as union rate, surgical wound infection and cut-outs rates were also recorded, along with the incidence of non-orthopedic complications and more surgical data. Functional results were evaluated and quantified using the Modified Harris Hip Score (MHHS) and by the Short Form 12 Mental Health Composite questionnaire (SF-12 MHC) in order to assess the quality of life. RESULTS: The total prevalence of postoperative orthopedic complications including postoperative infection showed a significant difference with a p-value of 0.016 in favor of the EPFN group. Nonetheless, the frequency of revision did not differ between the two groups, being 0.134. The main orthopedic complication in both groups was head cut-out of the GPFN lag screw and the EPFN expendable peg, which was 20% and 7.4%, respectively, and required a revision surgery using a long nail or total hip replacement (THR). However, the average TAD did not significantly differ between groups which might be due to a relatively low cohort to reach a significant difference. Nonunion rate of 5% occurred solely in the GPFN group, with similar results of intraoperative open reduction between both groups. The EPFN group achieved better scores in both questionnaires (p = 0.027 and p = 0.046, respectively). Both the MHHS and SF-12 MCS values significantly differed between groups, with the EPFN group achieving better scores than the GPFN group in both questionnaires (p = 0.027 and p < 0.05, respectively). CONCLUSIONS: According to this study, the EPFN yields better results in comparison with the GPFN, with relatively less complications rate, for the treatment of unstable reverse oblique pertrochanteric fracture. In light of this results, we conclude that the EPFN might be as good as GPFN for the treatment of reverse oblique intertrochanteric fractures. LEVEL OF EVIDENCE Level III retrospective study. The local institutional review board of the Tel Aviv Medical Center approved this study and all the surgeries were done exclusively in this institution.