Influence of femoral implant design modification on anterior knee pain and patellar crepitus in patients who underwent total knee arthroplasty without patella resurfacing

Abstract

Background: The incidence of patient dissatisfaction due to anterior knee pain (AKP) and patellar crepitus after total knee arthroplasty (TKA) remains a concern. However, it has been shown that improvements in the femoral component of traditional prostheses could reduce these instances of pain in the case of TKA performed with patellar resurfacing. This study aims to investigate whether TKA without patellar resurfacing can also benefit from the aforementioned femoral component modification in reducing AKP and patellar crepitus post-TKA. Methods: Sixty-two patients (85 knees) who underwent TKA using the modern prosthesis and 62 age-and sexmatched patients (90 knees) fitted with the traditional prosthesis were enrolled in this study. The occurrence of AKP and patellar crepitus as well as the Knee Society Score (KSS) were consequently recorded, and the data was analyzed in order to determine whether there was a statistically significant difference between the two groups. Results: The incidence of AKP was significantly lower in the study group compared with the control group at the 3-month and 1-year follow-ups (4.7% vs. 13.3% [p = 0.048] and 3.5% vs. 13.3% [p = 0.021], respectively). In addition, the incidence of patellar crepitus was also significantly lower in the study group compared with the control group at the 3-month and 1-year follow-ups (15.3% vs. 34.4% [p = 0.004] and 10.6% vs. 28.9% [p = 0.002], respectively). There was no significant difference in the KSS between the two groups. Conclusions: These results revealed that TKA without patellar resurfacing will indeed benefit from the modified femoral implant design in reducing AKP and patellar crepitus, a finding that may be beneficial to surgeons who select implants for their patients when patellar resurfacing is not planned or not possible due to other reasons.

The Role of Stability and Alignment in Improving Patient Outcomes After Total Knee Arthroplasty

“…(2) perioperative factors such as postoperative pain control; (3) medical factors such as a history of substance abuse, Parkinson disease, and/or diabetes mellitus; and (4) technical factors such as alignment and stability of the knee [6][7][8] .…”

“…Even though TKA is one of the most effective operations in orthopaedic surgery, 20% to 30% of patients who have TKA experience residual symptoms after surgery 3-5 . A variety of factors have been implicated in this dissatisfaction rate: (1) patient-specific factors such as preoperative expectations; (2) perioperative factors such as postoperative pain control; (3) medical factors such as a history of substance abuse, Parkinson disease, and/or diabetes mellitus; and (4) technical factors such as alignment and stability of the knee 6-8 .…”

Notching is less, if femoral component sagittal positioning is planned perpendicular to distal femur anterior cortex axis, in navigated TKA

“…Similarly, although insignificant ( p = 0.1475 and 0.228), the incidence of AKP was less in Attune versus PFC-Sigma knees in both the FBRD and the FBRE group in our study. Similarly, past studies [ 27 , 28 ] have shown that the incidence of AKP was less in patients with Attune implant in comparison with that in patients with PFC-Sigma implant.…”

No difference in 1-year improvement of patient-reported physical functioning and pain between resurfaced and unresurfaced patellae: analysis of 17,224 primary total knee arthroplasties in the Dutch Arthroplasty Register

“…Our study shows that CR-type prostheses with patellar resurfacing result in less improvement on the functional outcome measures (KOOS-PS and OKS). Some studies suggest that more modern "patella-friendly" femoral designs outperform other TKA designs by reducing AKP and patellar complications in the unresurfaced knees (25,26). We compared resurfaced and unresurfaced knees for several surgical systems and saw no benefit of patellar resurfacing.…”