Treatment of subtrochanteric fractures. A comparison of the Gamma nail and the dynamic hip screw: short-term outcome in 58 patients

The aim of this non-randomised prospective study was to evaluate the short-term outcome of Gamma nail and dynamic hip screw (DHS) fixation in the treatment of subtrochanteric hip fractures due to low-energy trauma in the elderly. All of the 1,624 femoral hip fractures in 1,511 patients of the Oulu Hospital, aged over 49 years, were prospectively registered from 1991−1999 using special forms. Seventy-three (4.5%) of the fractures were subtrochanteric. After exclusions, 58 patients constituted the final study group. Of these, 43 were treated with Gamma nails and 15 with DHS. Background factors before the fracture, complications, reoperations and functional parameters at 4 months were recorded using standardised forms. Intraoperative and hospital data were collected from patient records. The Seinsheimer fracture types IIIA, IIC and V were the most common fracture patterns when the Seinsheimer classification system was used, and Fielding II and AO 31A3.3, respectively, were the most common types in the Fielding and AO classification system. There were four (9%) intraoperative complications in the Gamma nail group as compared to none in the DHS group. On the other hand, postoperative complications were more common in the DHS group (27%) than in the Gamma nail group (7%). We recognised a correlation between certain fracture types and the likelihood of typical intra- or postoperative complications or difficulties with both devices: In Gamma nailing, difficulty in closed reduction as well as the rate of open reduction and the use of supplementary fixation were most frequent in the Seinsheimer IIC fractures. It is also noticeable that all of the postoperative device failures and fracture displacements of the DHS group occurred in the Seinsheimer type IIIA category. Detailed fracture classification is essential for the choice of the fixation device, and the present study confirms the presumption that, despite the perioperative problems associated with Gamma nailing, this technique may be preferable to plate fixation for specific fracture types with medial cortical comminution, such as Seinsheimer type IIIA.