RESUMO
OBJECTIVE: To conduct a systematic review to compare the early efficacies of minimally invasive surgery (MIS) versus conventional approaches in TKA (total knee arthroplasty). METHODS: Randomized controlled trials (RCTs) and clinical controlled trials (CCTs) were retrieved from the databases of MEDLINE (1996.6 - 2010.12), EMBASE (1996.6 - 2010.12), PubMed (1996 - 2010.12) and Cochrane Library (Issue 2, 2012). Journal of Orthopedics (from establishment to December 2010) and Orthopedic Journal of China (from establishment to December 2010) were manually searched. Both RCTs and CCTs were included. The data were extracted by two reviewers with designed extraction form RevMan 4.2.8 software for data analysis. The criteria were as follows: (1) operative duration and reduced blood loss; (2) VAS (visual analog scale) score; (3) faster recovery of ROM (range of movement); (4) quadriceps muscle strength; (5) component positioning malalignment; (6) tibiofemoral angle; (7) rate of complications. RESULTS: A total of 18 RCTs were included. Compared with the standard TKA procedure, the MIS group had a longer operative duration (WMD (weighted mean difference) 14.16, 95%CI (confidence interval) (12.61, 15.71)); reduced blood loss (WMD 8.31, 95%CI (6.16, 10.46)); lower VAS score at Days 3-5 post-operation (WMD 4.99, 95%CI (4.19, 5.78)); better Mean Knee Society scores at Week 6 post-operation (WMD 4.99, 95%CI (4.19, 5.78)), improvement in ROM occurred more rapidly at Month 3 post-TKA (WMD 14.59, 95%CI (8.39, 20.80)). Although the differences were not statistically significant, tibiofemoral angle was more precise in the standard group and the rate of component malalignment occurred more frequently in the MIS group (WMD 0.20, 95%CI (-0.12, 0.52)) (RR 1.57, 95%CI (0.88, 2.83)). CONCLUSION: MIS leads to a faster recovery than conventional surgery with a shorter operative duration, a reduced blood loss, a lower VAS score and a faster recovery of ROM and quadriceps muscle strength. However, the rates of component malalignment and complications occur more frequently in the MIS group. Potential benefits in long-term survival rate and functional improvement require further investigations.
