Total knee replacement performed with either a mini-midvastus or a standard approach

Abstract

We report the clinical and radiological results of a two- to three-year prospective randomised study which was designed to compare a minimally-invasive technique with a standard technique in total knee replacement and was undertaken between January 2004 and May 2007. The mini-midvastus approach was used on 50 patients (group A) and a standard approach on 50 patients (group B). The mean follow-up in both groups was 23 months (24 to 35). The functional outcome was better in group A up to nine months after operation, as shown by statistically significant differences in the mean function score, mean total score and the mean Oxford knee score (all, p = 0.05). Patients in group A had statistically significant greater early flexion (p = 0.04) and reached their greatest mean knee flexion of 126.5 degrees (95 degrees to 135 degrees ) 21 days after operation. However, at final follow-up there was no significant difference in the mean maximum flexion between the groups (p = 0.08). Technical errors were identified in six patients from group A (12%) on radiological evaluation. Based on these results, the authors currently use minimally-invasive techniques in total knee replacement in selected cases only.

Does Minimally Invasive Total Knee Arthroplasty Improve Isokinetic Torque?

“…Analogous to our study, Chin et al [7] measured the postoperative leg axis from whole-leg radiographs and reported inferior alignment in MIS TKA. The authors of other studies investigating the radiographic outcome of MIS TKA assessed component alignment alone [19,27], defined the leg axis on short standard radiographs [11,13,21], or did not mention the method used to measure the leg axis [20]. The clinical importance of the low mean valgus leg axis in MIS TKA we observed is debatable because published data concerning the consequences of tibiofemoral malalignment on TKA survival are controversial [17,39].…”

“…The same has been observed with respect to radiographic findings (leg alignment and/or component alignment). Some authors reported inferior radiographic alignment [7,19,44], whereas others reported similar alignment [11,13,15] for MIS and standard TKAs. There is some consensus in the literature regarding the rate of improvement in ROM; many authors have reported a faster gain in ROM for patients having MIS TKA, at least during the first few weeks postoperatively [8, 11-13, 18, 19, 21, 27].…”

Does Minimally Invasive Surgery Improve Short-term Recovery in Total Knee Arthroplasty?

“…However, prolonged postoperative pain and delayed return of function that may contribute to patient dissatisfaction or lengthy recuperative periods are the major concerns with the standard surgical approaches [20]. The concept of MIS TKA, introduced more than a decade ago, has created debate as a result of interest from orthopaedic surgeons and patients [46].…”

“…Defining MIS based on only the incision size is inappropriate; the aim of minimally invasive arthroplasty is to minimize damage to soft tissues and consequently to quadriceps function and knee stability. One study defined MIS TKA as an approach that was less damaging to the extensor mechanism and avoided eversion of the patella [20]. Several MIS TKA techniques have been described: traditional mini (mini-medial parapatellar [15], mini-midvastus [20,21], mini-subvastus [22,43]) and fully innovative techniques (quad-sparing) [25,39,48].…”

“…Several MIS TKA techniques have been described: traditional mini (mini-medial parapatellar [15], mini-midvastus [20,21], mini-subvastus [22,43]) and fully innovative techniques (quad-sparing) [25,39,48]. Advocates of MIS TKA commonly suggest it allows patients faster recovery time [9,15], less blood loss [20], decreased soft tissue trauma [30,37], more pain relief [18], better cosmetic appearance [15,18,26], and measurable improvement of function [9,15,48]. Critics of MIS TKA emphasize possible complications associated with long-term outcomes (eg, lower survival rates) and the length of the learning curve [31,38].…”