Comparative study on early period of recovery between minimally invasive surgery total knee arthroplasty and minimally invasive surgery-quadriceps sparing total knee arthroplasty in Chinese patients

Background Different kinds of minimally invasive surgery (MIS) procedures have now been used in total knee arthroplasty (TKA). Compared with traditional TKA procedure with a long skin incision, 'clinical studies showed MIS procedures had some advantages. Quadriceps sparing (QS) procedures are the most minimally invasive MIS procedure until now. This study was aimed to find the insertion types for Chinese patients' vastus medialis and if the QS procedure had some advantages in patients' early recovery. Methods Between February 2006 and May 2007, 120 consecutive patients underwent unilateral primary TKA under general anesthesia, among whom 14 patients were lost to follow-up, the remaining 106 cases were enrolled in this study. Among the 106 cases there were 85 right knees, 21 left knees (15 men and 91 women, with a mean age of 65.1 +/- 7.4 years); osteoarthritis in 97 patients (91.5%) and rheumatoid arthritis in 9 patients (8.5%). MIS TKA was performed in 49 cases (MIS TKA group), while MIS-QS TKA in 57 cases (MIS-QS TKA group). During the operation, the type 1, 11 and III insertions of the vastus medialis for all patients were recorded. Each knee was rated post-operatively according to the Hospital of Special Surgery (HSS) scoring system. Clinical follow-up was undertaken at 1 week, 2, 6, 12 and 24 weeks. Operating time and complications were recorded. Results There was no statistically significant difference between the two groups for gender distribution, age, left or right knee incidence, pre-operative diagnosis, incidence of varus or vaigus deformity. Of the 106 cases there was 1 (0.9%) case with a type I insertion of the vastus medialis, 4 (3.8%) cases with type 11 insertions, 101 (95.3%) cases with type III insertions. The HSS scoring was significantly different between the MIS-QS TKA group and MIS TKA group within the first two weeks post operation. From 2 weeks later to 24 weeks, no significant difference was found. The average operating time was (53.3 +/- 12.4) minutes in the MIS TKA group and (64.1 +/- 15.1) minutes in the MIS-QS TKA group (P <0.001). In the MIS-QS TKA group, 1 patient had delayed healing of the partial skin incision (1.8%). No other complications were found in either group. Conclusions Although most of the Chinese patients had type III insertions of the vastus medialis, the MIS-QS TKA procedure showed less injury to the quadriceps than the standard MIS TKA and this could contribute to the earlier recovery of the patients. But a shorter skin incision and more tension on the skin may also lead to more skin complications.