[Special surgical technique of minimally invasive total knee replacement]

Due to the initial disappointing experience with minimally invasive knee arthroplasty, many surgeons still prefer the conventional technique. Sharing technical details, personal insights and results may help abbreviate the individual learning curve towards successful MIS.

Based on the experience of over 250 minimally invasive knee arthroplasties an operative algorithm was developed and evaluated to assure optimal realization of a gentle joint replacement using a mini-mid-vastus incision. Short-term results were compared to those of the conventional technique with particular regard to pain, use of analgesic medication, flexion of the knee and achievements at physiotherapy.

In comparison to the conventional procedure, MIS produced significantly better results regarding pain and function during early rehabilitation and did not affect the perfect positioning of the implants. The morphine-equivalent dose was less than a half on day 2 after operation. Flexion on days 1 and 3 was 70 degrees and 75 degrees respectively. 80 degrees were obtained after 4 days and after 6 weeks flexion was at an average of 115 degrees . In contrast, results of the conventional control group were notably worse, with 50 degrees and 65 degrees on days 1 and 3, 80 degrees being obtained on day 6 only and a mean flexion of 100 degrees after 6 weeks.

The special surgical technique of minimally invasive knee arthroplasty accelerates and facilitates the rehabilitation of the patient and thereby defines a new quality standard.