JOA - 2026-06-23 - Journal Article
Classification and Outcomes of 214 Periprosthetic Patellar Fractures in Primary Total Knee Arthroplasty.
Ducharme MT, Selemon NA, Bedard NA, Spangehl MJ, Springer BD, Hidden KA, Yuan BJ, Berry DJ, Abdel MP, Hannon CP
Topics
Key Takeaway
Type II and III periprosthetic patellar fractures carry dramatically higher revision risk than Type I, with 10-year revision-free survivorship of 60% for Type II versus 80% for Type I and hazard ratios of 8.4 and 17.0 for Types II and IIIA, respectively.
Summary Depth
Choose how much analysis to show on this article page.
Summary
This study classified and analyzed outcomes of 214 periprosthetic patellar fractures following primary TKA at a single institution from 1989–2020 using the Ortiguera and Berry classification. Postoperative fractures (n=206) were predominantly Type I (76%), with 66% occurring atraumatically; 10-year revision-free survivorship was 71% overall but dropped to 60% for Type II and was further compromised in Types IIIA and IIIB. Intraoperative fractures (n=8, incidence 0.02%) were rare and carried 88% 10-year revision-free survivorship.
Key Limitation
The 31-year study window encompasses substantial evolution in patellar implant design, cementing technique, and surgical approach, making it impossible to attribute outcomes to any specific technical or implant variable.
Original Abstract
INTRODUCTION
Long-term data following periprosthetic patellar fractures around primary total knee arthroplasty (TKA) are lacking. The purpose of this study was to describe the classification, management, and outcomes of periprosthetic patellar fractures in, to our knowledge, the largest series to date.
METHODS
We identified 214 (213 cemented and one uncemented) periprosthetic patella fractures (205 patients) around a primary TKA sustained between 1989 and 2020. There were eight intraoperative fractures and 206 postoperative fractures. Postoperative fractures were classified according to the Ortiguera and Berry classification. There were 76% Type I fractures, 12% Type II fractures, 6% Type IIIA fractures, and 6% Type IIIB fractures. The mean patient age was 66 years (range 22 to 90), 56% were men, and their mean body mass index (BMI) was 32 (range, 21 to 54). The mean patient follow-up was seven years (range, two to 19).
RESULTS
The incidence of intraoperative patellar fracture was 0.02%, occurring most frequently during exposure, implant preparation, or trialing (75%). The 10-year survivorships free of any revision and any reoperation after intraoperative fractures were both 88%. Among the 206 postoperative fractures, the majority (66%) occurred atraumatically, while 31% occurred after ground level falls. Among postoperative fractures, the 10-year survivorship free of any revision and any reoperation was 71 and 61%, respectively. Revision and reoperation risk after postoperative fracture varied by Ortiguera and Berry classification. The 10-year survivorship free of any revision was highest in Type I (80%) and significantly lower in Type II (60%) fractures. Compared to Type I fractures, survivorship free of revision was decreased in Type II (hazard ratio (HR) 8.4, P < 0.001), Type IIIA (HR 17.0, P < 0.001) and Type IIIB (HR 8.1, P < 0.001) fractures. Mortality following postoperative periprosthetic patellar fractures was 7% at two years and 55% at 10 years.
CONCLUSION
Intraoperative periprosthetic patellar fractures during primary TKA were rare and generally well-tolerated. Ortiguera and Berry Types II and III fractures were associated with the highest risk of revision and reoperation.