Impact of Age on Patello-femoral Arthroplasty Outcomes, Osteoarthritis Progression, and Survivorship: The Youngest and Oldest Achieve the Best Results

Background: Proper patient selection is essential to improve long-term outcomes in patellofemoral arthroplasty (PFA). This study aimed to assess the impact of age on functional outcomes, osteoarthritis (OA) progression, and survivorship in patients who underwent PFA using a modern implant. Methods: Patients who underwent primary isolated PFA with third-generation prosthesis were retrospectively reviewed. A total of 120 PFAs with a mean follow-up of 8.6 years were included. Patients were categorized into four age groups: Group I (< 55 years), Group II (56 to 65 years), Group III (66 to 75 years), and Group IV (> 76 years). Clinical and radiographic outcomes included knee range of motion, Knee Society scores, University of California Los Angeles Activity Score, Tegner Activity Scale, OA progression, and patient satisfaction. Survival analysis was also conducted. Results: Patients in Group I demonstrated significantly better functional outcomes, including higher Knee Society, Tegner, and University of California Los Angeles scores, compared to older groups (P < 0.01). Group I also showed the highest engagement in medium to low-impact sports (92%) and no significant OA progression. Groups I and IV had a 100% survivorship rate; in contrast, group II exhibited the lowest survivorship rate (90%) due to OA progression. Conclusions: A PFA in patients under 55 years resulted in superior clinical outcomes, minimal OA progression, and high survivorship rates. Even patients over 76 years demonstrated an excellent survival rate along with satisfactory clinical outcomes. Conversely, patients aged 56 to 65 years demonstrated the highest risk of revision. This study supports the effectiveness of PFA as a treatment option for isolated patello-femoral OA in very young and very old patients.