Total knee arthroplasty was an effectiveness method for treatment the severe osteoarthritis of knee which has been approved and accepted by the orthopedic community. This technique has been developed more than thirty years and the clinical results have been followed up over twenty years and reliable by the orthopedic doctors. But postoperative pain and long period of recovery times and rehabilitation program were the major problems of the traditional total knee arthroplasty. There has been recent attention concerning minimally invasive technique for knee arthroplasty. Reviewing the relative articles, the surgical criterias were limited to knee varus < 10 degree or valgus < 15 degree and flexion contracture < 10 degree. It is not clear whether these complicated technique can be reproduced to knee varus <10 degree, or valgus < 15 degree and flexion contracture 10 to 15 degree.
This prospective study was carried out under the particular criteria to assess safety, satisfaction and efficacy of a minimally invasive total knee arthroplasty comparison to traditional total knee arthroplasty. The study consisted of 48 knees, including 25 knees receiving traditional procedure and 23 knees receiving minimally invasive procedure.
The results revealed that the mean skin length, mean total blood loss, mean hospital staying in the minimally invasive group were shorter than the traditional group and statistic significantly. But the mean operation time was longer (P<0.05) in the minimally invasive group. There were one partial popliteal tendon injury and two tibial component mildly internal rotation in the minimally invasive group. The above complications did not affect the finally clinical results. The early mean knee society scores, including objective and functional scores, minimally invasive group was better than traditional group but the difference got closely after 12 weeks postoperation and similar results were found at 6 months and 12 months following up postoperation. The satisfaction of both groups were similar after one year postoperation. The residual flexion contracture of knee was higher in minimally invasive group, but the p value > 0.05 and no statistic significantly. Most of the cases were shorter and obesity patient (body weight > 80kg). In this study, minimally invasive total knee arthroplasty showed less total blood loss, shorter hospital staying, quickly early range of motion and similar complication rate to traditional total knee arthroplasty. In summary, under the limited criterias, minimally invasive technique could be safety reproducible and created functional satisfaction.
But this technique should need longer period to follow its clinical results.
