The effect of the "mini" incision in total hip arthroplasty on component position.

This study compares cemented and uncemented total hip arthroplasties performed through either a standard or mini incision. The parameters evaluated were dislocation rates, Gruen and DeLee zones, Barrack cement grading, component positioning, and heterotopic bone levels. There were no statistically significant differences found between the mini and standard incision groups except in 2 parameters. Analysis of femoral stems not in neutral position revealed statistically significant differences between cemented and uncemented stems. The mean anteversion of the mini incision cup was also significantly less than the standard group, although probably not clinically significant. In conclusion, the mini incision does not compromise total hip arthroplasty results on the acetabular side, but varus positioning of the cemented femoral component nearing 2 degrees is concerning for the long-term success of these arthroplasties.