Clinical Evaluation of Efficacy and Performance of All-Poly Tibial Freedom® Total Knee System for Treating Osteoarthritis Patients: Three-Year Follow Up Study

J Clin Diagn Res. 2017 Sep;11(9):RC01-RC05. doi: 10.7860/JCDR/2017/26418.10671. Epub 2017 Sep 1.

Abstract

Introduction: Advancement in technology in terms of design and building materials has made Total Knee Replacement (TKR) a highly effective, safe, and predictable orthopedic procedure.

Aim: To review the clinical outcomes for efficacy and performance of Freedom Total Knee System for the management of Osteoarthritis (OA), at a minimum of three years follow up.

Materials and methods: For this retrospective, post-marketing study, clinical data of patients treated with Freedom Total Knee System was retrieved from the clinical records after approval from the Institutional Ethics Committee . All the patients above the age of 18 years who completed at least three years after TKR were observed for the study purpose. Patients treated for OA were included while the patients who received the implant for treatment of rheumatoid arthritis and traumatic injury were excluded. Factors such as aseptic loosening, implant failure, and need for revision surgery were observed to evaluate implant performance. Cases were recruited for clinical assessment of primary efficacy endpoint in terms of post-surgery maximun range of motion. Secondary efficacy endpoint was to determine the clinical and social quality of life as per the American Knee Society Score (AKSS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and stiffness scores.

Results: A total of 158 patients who had 191 TKR were observed for performance. The mean age of the patients was 67.67 years; mean BMI was 28.97±3.33, and the group comprised of 43% men and 57% women. Telephonic follow up at three years of 158 patients identified that none of them required revision surgery or had aseptic loosening suggesting excellent performance. Final clinical follow up at three years was available for only 35 patients (41 knee implants). The range of motion significantly improved from preoperative 104°±5.67° (range, 85°-119°) to 119.8°±11.05° (98°-123°) at follow-up (p<0.05). There was a significant improvement in clinical and functional AKSS score and WOMAC score at follow-up.

Conclusion: The evaluation of Freedom Total Knee System for TKR in treating OA, at a minimum of three years follow up showed excellent outcomes in terms of performance, range of motion, reduced postoperative stiffness and pain, and improved functionality.

Keywords: AKSS scores; All-poly tibial component; Range of motion; Total knee replacement; WOMAC score.