Twenty-five randomised studies were included initially and were reported in the analysis. However, the authors reported that 20 studies were included. The same sample size (n=3,464) was reported for both sets of studies. The authors did not present any detailed quality assessment results.
Femoral hip fracture rates varied from zero to 17% in patients treated with Gamma nails and zero to 3% in patients with compression hip screw. Overall, Gamma nails showed a significantly increased risk of femoral shaft fracture compared with compression hip screws (RR 2.93, 95% CI 1.51 to 5.68; 25 studies, n=3,464).
Analysed by time (year of study), earlier studies (1988 to 1996) showed a significantly higher risk of femoral shaft fracture with Gamma nails compared to compression hip screw (RR 4.5, 95% CI 1.78 to 11.36; 11 studies; n=1,585). Recent studies (1997 to 2005) did not show increased risk with Gamma nails compared to compression hip screws (RR 1.87, 95% CI 0.73 to 4.82; 13 studies; n=1,879). Very recent studies (2000 to 2005) also did not show increased risk with Gamma nails compared to compression hip screws (RR 1.65, 95% CI 0.5 to 5.44; eight studies; n=1,431).
No heterogeneity was detected between the included studies (I2=0%) for all the pooled analyses.