Minimally Invasive (Epivastus) Approach for Total Knee Arthroplasty.

The aim of the study was to assess the efficiency of a developed minimally invasive (epivastus) approach in total knee arthroplasty (TKA) by comparing its early results with those of a standard medial mediapatellar approach (MMPA).

Materials and methods: A single-center, comparative randomized prospective study involved 127 patients, who underwent TKA using MMPA (n=62) and a modified minimally invasive epivastus approach (n=65) within the period from January to December, 2022. The study groups were comparable by gender, age, BMI, gonarthrosis stage, and knee joint functioning parameters.

Results: The surgery duration in the epivastus group was significantly lower compared to MMPA group (p<0.001). However, the interpretation of tissue trauma markers assessment appeared rather ambiguous. There were no statistically significant differences in lactate dehydrogenase (p=0.253). C-reactive protein, myoglobin, creatinine showed a significant increase in MMPA group (p<0.001; p=0.002 and p=0.048, respectively), while aspartate aminotransferase, creatine phosphokinase and ESR, in contrast, increased in the epivastus group (p<0.001; p=0.024 and p=0.010, respectively). Pain syndrome determined by VAS 3 days after the surgery was significantly lower in the epivastus group (p=0.006). The extent of blood loss appeared to be much greater in MMPA group (p=0.006). The joint function indicators on day 3 after the surgery were found to be better in the patients after TKA using an epivastus approach (p<0.001). The postoperative assessment of the endoprosthetic spatial orientation showed the indicators characterizing the correct endoprosthetic implantation to be comparable in both groups (p≥0.06).

Conclusion: The present study demonstrated the efficiency of the developed minimally invasive (epivastus) approach in TKA. However, it should be taken into consideration that surgeons should take a training course to be able to accomplish a high-quality approach.An ambiguous interpretation of tissue trauma markers assessment of performing minimally traumatic approaches requires terminology correction. It is probably necessary to change the approach to the approach marking and use the terms specifying minimal invasiveness and the reduction of muscle injury rather than soft tissues in general.