TITLE: Results of TKA with Porous Tantalum Monoblock Tibial Component

TITLE: Results of TKA with Porous Tantalum Monoblock Tibial Component

Clinical and Radiographic Results of 105 Knees

AUTHOR(S): Amir A. Shahien, MS; Hilary W. Thompson, PhD; Vinod Dasa, MD

AFFILATION(S): Department of Orthopedic Surgery, LSUHSC, New Orleans, LA, 70112; Department of Biostatistics, LSUHSC, New Orleans, LA 70012

______

Background: The use of uncemented total knee arthroplasty (TKA) with monoblock tibial component has regained favor in orthopedic practice due to the improvement of biomaterials and reduction in complications and revisions.

Design and Methods: This retrospective cohort study examined patient reported clinical outcomes and radiographic data of 105 TKAs. The clinical outcome measure data were gathered via patient-reported surveys, including Oxford Knee score (OKS), WOMAC score (WS), Short Form 12 score (SF-12), and the American Knee Society function score (KSS). Post-operative radiographs were evaluated for radiolucence, subsidence, and angles of varus/ valgus alignment. Survey score trends over time and post-operative radiograph measurements were analyzed by multiple regression, logistic regression, and t-test comparison of means with the SAS statistical package.

Results: The average age of patients undergoing TKA at time of surgery was 59 years (range 24 – 70) and the average follow-up time for patients was 30 months. The average BMI of patients undergoing TKA was 35 (range 19 – 55). There was significant improvement between the mean values of pre-operative and post-operative survey scores for the Oxford Knee score (OKS) (p< .0001), WOMAC score (WS) (p< .0001), and Short Form 12 score (SF-12) (p 0.0018), respectively, regardless of patient BMI, height, age, and sex. Additionally, there was no difference in post-operative radiographic measurements of the femorotibial angle, tibial component coronal angle, and tibial component sagittal angle between groups of patients categorized by BMI, height, age, and sex. In the cohort analyzed, there were two surgical revisions, neither due to failure of the tibial component.

Conclusion: Although it has been recently suggested that stringent patient selection is an essential precursor to the successful outcomes following TKA with monoblock tibial component, this study suggests that there is significant clinical improvement and no radiographic evidence of post-operative complications regardless of patient demographic factors such as BMI, height, age, and sex.