A COMPARATIVE STUDY OF THE MIDVASTUS AND MEDIAL PARAPATELLAR APPROACHES FOR TOTAL KNEE ARTHROPLASTY IN THE EARLY POSTOPERATIVE PERIOD

Objective To compare clinical parameters associated with medial parapatellar and midvastus approaches for total knee arthroplasty in the early post-operative period. Methods and results We present a prospective observational study of 77 patients undergoing primary total knee arthroplasty using medial parapatellar(40) or midvastus approach(37). The prosthetic design and physical intervention was standardised in all the patents. The Oxford Knee Score, pain scale, knee flexion, unassisted straight leg raise, standing and walking were compared at 3rd, 5th and 7th day post-operatively, then at 6 weeks and at 3 months. The patients and physiotherapist were blinded to the type of approach used. The average age was 67 years (range 42 to 88). There were 42 women and 35 men. The average hospital stay was 7 days (range 2 to 15). There was statistically significant difference in duration of hospital stay, unassisted straight leg raise and standing at 3 days (p=0.001) and pain scale at 5 days, all in favour of midvastus approach. There was no statistically significant difference in Oxford Knee Scores and duration to achieving full flexion and walking. The average duration to achieving straight leg raise for the midvastus group was 5 days and for the medial parapatellar approach group was 8 days. Conclusion The study shows that total knee arthroplasty performed through the midvastus approach resulted in less post-operative pain, earlier unassisted straight leg raise and ambulation and, therefore, shorter hospital stay as compared to a medial parapatellar approach.