Abstract
Objectives
We aimed to evaluate the relationship between Wiberg patella type and outcomes following cell-based cartilage repair (autologous chondrocyte implantation [ACI] or particulated juvenile allograft cartilage transplantation [PJAC]) for the treatment of patellar chondral lesions at minimum 2-year follow-up. We hypothesized that Wiberg classification of patella shape would have no impact on patient-reported outcome measures (PROMs) or graft survival.
Methods
Patients undergoing ACI or PJAC for full-thickness patellar chondral defects between 2016-2020 were retrospectively reviewed following Institutional Review Board approval. The change in PROMs, including International Knee Documentation Committee (IKDC), Kujala, Veterans Rand 12 (VR-12) Mental, and VR-12 Physical scores, from pre- to postoperative and the percentage of patients who achieved the MCID for IKDC and Kujala scores were compared for the Wiberg A versus Wiberg B versus Wiberg C groups. Log-rank test was used to evaluate for differences in survival between subgroups.
Results
Fifty-nine patients (63 knees) were included, with an average age of 33.3±8.6 years, median BMI of 26.0 kg/m2 (interquartile range:21.8–30.2 kg/m2), and median time to follow up of 3.5 years (interquartile range:2.6–4.2 years). Twenty-six patellae (41%) were Wiberg type A, 29 (46%) were Wiberg type B, and 8 (13%) were Wiberg type C. There were no differences between Wiberg A versus B versus C groups with respect to change in PROMs from pre- to postoperative or the percentage of patients who achieved the MCID for IKDC or Kujala scores (p>0.05 for all). There were no differences in survival between groups (p=0.45).
Conclusion
Wiberg patella type has no impact on patient-reported outcomes or graft survival at midterm follow-up. Patella dysplasia should not be seen as a contraindication for cell-based cartilage repair procedures.