Introduction: Technical and patient care improvements have occurred with the posterior mini-incision total hip replacement (THR). The hypothesis of this study was that these changes would provide better results for patients in the posterior mini incision surgery (MIS) THRs performed in our institution.

Methods: The clinical and radiographic results of 100 THRs performed with the posterior mini incision between January 2004 and October 2004 were compared with 100 mini incision THRs performed between December 2001 and September 2002. The second group was subjected to improved operative technique, the post-operative analgesia protocol, rehabilitation and patient advise. The acetabular cup abduction angle, anteversion angle, and stem varus/valgus alignment angle were measured in the post-operative radiographs in both groups. Pain score and Harris hip score were recorded at 6 weeks and 3 months. Statistical analysis was performed using Student 2-tailed t test, Chi-squared test and Wilcoxon-Mann-Whitney tests to compare the incision length, operative time, estimated blood loss, length of hospital stay, pain score and radiographic measurements between the two groups.

Results: The results showed that the component positions were not compromised in either group. There were statistical improvements in 2004 group with less estimated blood loss, decreased hospital stay, reduction of postoperative pain and opioid analgesic use and earlier muscle recovery. In 2004 group there were no complications of infection, dislocation, or sciatic palsy.

Discussion: The posterior mini-incision operation has shown improved results with experience and changes in technique and patient care treatment. We have continued our practice using this new technique.