A two to fifteen year follow-up case series of ninety one patients after onlay patellofemoral arthroplasty highlighting the impact of preoperative symptoms and mental health.

Onlay patellofemoral arthroplasty produced significant improvements in WOMAC total scores from preoperative to final follow-up.

• WOMAC total score improved from 57.3% preoperatively to 22.5% at final follow-up (p < 0.001)
• Follow-up data were available for 91 knees (88 patients) with a mean follow-up of 6.1 ± 3.4 years
• Mean patient age was 60.7 ± 10.3 years
• The study used a retrospective design covering surgeries performed between 2009 and 2023 using the Journey™ PFJ implant (Smith & Nephew)

Onlay PFA resulted in significant improvements in both physical and mental health quality of life scores as measured by the SF-12.

• SF-12 physical component score improved from 29.6 preoperatively to 43.5 at final follow-up (p < 0.001)
• SF-12 mental component score improved from 46.8 preoperatively to 52.7 at final follow-up (p < 0.001)
• Both physical and mental improvements were statistically significant at p < 0.001

Onlay PFA resulted in significant improvements in pain and functional outcomes as measured by the numerical analog scale.

• NAS function score improved from 4.7 preoperatively to 7.2 at final follow-up (p < 0.001)
• NAS pain score improved from 7.8 preoperatively to 3.1 at final follow-up (p < 0.001)
• Both NAS pain and function improvements were statistically significant at p < 0.001

Patients who did not achieve the minimal clinically important difference had significantly higher preoperative WOMAC scores than those who did.

• Patients not achieving MCID had mean preoperative WOMAC scores of 61.3% compared to 46.0% in those who achieved MCID (p = 0.018)
• A high preoperative WOMAC score was identified as a potential predictor of less favourable postoperative outcomes

Preoperative mental health status as measured by the SF-12 mental component summary score was correlated with both pre- and postoperative WOMAC scores.

• SF-12 mental component summary (MCS) scores were correlated with pre- and postoperative WOMAC scores (r2 = 0.21–0.32; p ≤ 0.002)
• Poor mental health, as indicated by the SF-12 MCS, may be associated with less favourable postoperative outcomes
• The correlation applied to both preoperative and postoperative WOMAC measurements

Kaplan-Meier analysis demonstrated declining but acceptable implant survivorship rates over 5, 10, and 15 years.

• PFA survivorship rates were 89% at five years, 75% at ten years, and 67% at 15 years
• The original cohort comprised 128 knees (123 patients) who underwent onlay PFA between 2009 and 2023
• Follow-up data were available for 91 knees (88 patients), representing a follow-up rate of approximately 71% of knees

Patellofemoral osteoarthritis substantially impairs quality of life and isolated patellofemoral arthroplasty is a surgical option for therapy-refractory symptoms.

• The study included patients with PFOA who underwent onlay PFA using the Journey™ PFJ implant (Smith & Nephew)
• Patients were retrospectively analyzed with assessments of WOMAC, SF-12, and NAS for pain and function preoperatively and at final follow-up
• Postoperative complications and revisions were also recorded