BACKGROUND: This retrospective medium-term follow-up study compares the outcomes of medial fixed-bearing unicompartmental knee arthroplasty (mUKA) using a cemented metal-backed (MB) or an all-polyethylene (AP) tibial component.
METHODS: The database of our institution was mined for primary mUKA patients implanted with an MB or an AP tibial component (the MB-UKA and AP-UKA groups, respectively) from 2015 to 2018. We compared patient demographics, patient-reported outcome measures (PROMs), and motion analysis data obtained with the Riablo™ system (CoRehab, Trento, Italy). We conducted propensity-score-matching (PSM) analysis (1:1) using multiple variables.
RESULTS: PSM analysis yielded 77 pairs of MB-UKA and AP-UKA patients. At 5 years, the physical component summary (PCS) score was 52.4 ± 8.3 in MB-UKA and 48.2 ± 8.3 in AP-UKA patients (p < 0.001). The Forgotten Joint Score (FJS-12) was 82.9 ± 18.8 in MB-UKAs and 73.4 ± 22.5 in AP-UKAs (p = 0.015). Tibial pain was reported by 7.8% of the MB-UKA and 35.1% of the AP-UKA patients (p < 0.001). Static postural sway was, respectively, 3.9 ± 2.1 cm and 5.4 ± 2.3 (p = 0.0002), and gait symmetry was, respectively, 92.7% ± 3.7 cm and 90.4% ± 5.4 cm (p = 0.006). Patient satisfaction was 9.2 ± 0.8 in the MB-UKA and 8.3 ± 2.0 in the AP-UKA group (p < 0.003).
CONCLUSIONS: MB-UKA patients experienced significantly better 5-year static sway and gait symmetry outcomes than AP-UKA patients. Although the PROMs of the two groups overlapped, MB-UKA patients had a lower incidence of tibial pain, better FJS-12 and PCS scores, and were more satisfied.

While considered a satisfactory solution, unicompartmental knee arthroplasty (UKA) still raises concerns in regard to its durability. These concerns particularly focus on the tibial component. This study aims to compare two different cemented tibial components belonging to the same UKA design: all polyethylene (AP) versus metal backed (MB), at a long-term follow-up.
We retrospectively reviewed 143 successive patients, 83 of which underwent surgery with AP tibial component UKA (37 males, 46 females), and 67 with MB ones (17 males, 50 females). All implants had the same prosthetic design (Accuris UKA, Smith e Nephew) with identical femoral oxinium component but different tibial component, AP or MB. The KSS and KOOS were assessed at a mean of 11.5-year follow-up and compared to pre-operative, post-operative, and one year evaluation. Statistical analysis was performed with SPSS for Mac (version 17.0). To assess potential statistically significant differences, t test was used and significance was set at P < 0.05.
Final KSS at a mean of 11.5-year follow-up was 94.27 for the AP group and 96.12 for the MB ones. The final KOOS was 87 for AP components and 89.67 for the MB group. These results demonstrated, in all cases, statistically significant better results for MB tibial components compared to AP regarding KSS (P = 0.048), KOOS (P = 0.000), and pain (P = 0.014) at the 11.5-year follow-up. Survivorship for AP tibial component implants was 97.6%, while it was 89.5% for MB ones.
While the survivorship rate has been found to be greater for AP implants compared to MB tibial components, this study reveals statistically better functional results according to KSS and KOOS, and pain, at a long-term follow-up for MB implants.

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