To Resurface or Not to Resurface the Patella in Total Knee Arthroplasty, That Is the Question: A Meta-Analysis of Randomized Controlled Trials

Total knee arthroplasty without patella resurfacing leads to worse results in patients with patellafemoral osteoarthritis Iwano Stages 3-4: a study based on arthroplasty registry data

PURPOSE

To determine whether the preoperative degree of degeneration of the patellofemoral joint really affects the outcome of total knee arthroplasty (TKA) surgery without patella resurfacing and thus to establish a parameter that might serve as a guiding factor to decide whether or not to perform retropatellar resurfacing. It was hypothesized that patients with preoperative mild patellofemoral osteoarthritis (Iwano Stages 0-2) would significantly differ from patients with preoperative severe patellofemoral osteoarthritis (Iwano Stages 3-4) in terms of patient-reported outcome (Hypothesis 1) and revision rates/survival (Hypothesis 2) after TKA without patella resurfacing.

METHODS

Application of a retrospective-comparative design on the basis of Arthroplasty Registry data that included patients with primary TKA without patella resurfacing. Patients were allocated to the following groups based on preoperative radiographic stage of patellofemoral joint degeneration: (a) mild patellofemoral osteoarthritis (Iwano Stage ≤ 2) and (b) severe patellofemoral osteoarthritis (Iwano Stages 3-4). The Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC) score was assessed preoperative and 1 year postoperative (0: best, 100 worst). In addition, implant survival was calculated from the Arthroplasty Registry data.

RESULTS

In 1209 primary TKA without patella resurfacing, postoperative WOMAC total and WOMAC subscores did not differ significantly between groups, but potentially suffered from type 2 error. Three-year survival was 97.4% and 92.5% in patients with preoperative mild and severe patellofemoral osteoarthritis, respectively (p = 0.002). Five-year survival was 95.8% vs. 91.4% (p = 0.033) and 10-year survival was 93.3% vs. 88.6% (p = 0.033), respectively.

CONCLUSIONS

From the study findings, it is concluded that patients with preoperative severe patellofemoral osteoarthritis have significantly higher risks for reoperation than do those with preoperative mild patellofemoral osteoarthritis-when treated with TKA without patella resurfacing. Hence, it is recommended that patella resurfacing be applied in patients with severe Iwano Stage 3 or 4 patellofemoral osteoarthritis during TKA.

LEVEL OF EVIDENCE

III, Retrospective comparative.

Outcomes and Survivorships of Total Knee Arthroplasty Comparing Resurfaced and Unresurfaced Patellae

BACKGROUND

The decision to resurface the patella in total knee arthroplasty (TKA) is controversial. While there is some consensus that leaving the patella unresurfaced increases risk of reoperation, there is conflicting evidence about patient reported outcomes or indications for resurfacing. This study sought to determine recent rates of patellar resurfacing, examine factors affecting rates of resurfacing, and analyze the associations between patellar resurfacing and both revision rates and patient-reported outcome measures (PROMs).

METHODS

The American Joint Replacement Registry was used to identify primary TKAs performed for osteoarthritis between 2012 and 2021. Cases were classified as resurfaced patella and unresurfaced patella (URP). Outcomes analyzed included trends in patellar resurfacing, factors influencing rate of resurfacing, revision rates, operative time, and 2 PROMs.

RESULTS

Rates of patellar resurfacing decreased and rates of URP increased significantly faster in ambulatory surgery centers and among high volume surgeons. Operative time was significantly lower in URP versus resurfaced patella (88.15 versus 89.90 minutes). The URP were significantly more likely to require revision surgery (odds ratio = 1.206 (1.078, 1.35), P = .0011). There was no significant difference in the likelihood of achieving the minimal clinically important difference in PROMs between resurfaced and nonresurfaced TKAs at 1 year (odds ratio = 1.060 (0.710, 1.581), P = .7755).

CONCLUSION

There was no difference in minimal clinically important difference between resurfaced and URPs and no clinically relevant difference in operative time. However, URPs were more likely to require revision surgery. Therefore, the decision not to resurface should be made carefully considering the known risk of revision and the uncertain benefit.

Patellar Resurfacing in Total Knee Arthroplasty, a Never-Ending Controversy; Case Report and Literature Review

Total knee arthroplasty (TKA) remains a lifesaving procedure for advanced gonarthrosis. However, patella resurfacing (PR) in TKA remains a controversial procedure, leading to extensive discussions amongst orthopedic surgeons, regarding its indications and results. Based on these premises, we present a clinical case of a 70-year-old Caucasian woman admitted for pain, swelling and limitation of left knee joint mobility. Her medical history records an Ahlback stage IV gonarthrosis with simultaneous bilateral TKA surgery performed in different hospital, when two NexGen cemented total prostheses were implanted with patellar resurfacing being performed only on the right side. Our clinical (American Knee Society Score, Lonner and Feller scales) and radiological evaluations (CT scan and Xray) revealed left patellar arthrosis and a slight lateral subluxation of the patella. The chosen treatment plan was revision surgery for PR and patellar prosthesis with a cemented patellar component, cross-linked polyethylene, no 32 NexGen model with 8.5 mm thickness. The immediate and distant postoperative evolution was favorable. Extensive literature review shows that, at present, PR remains at surgeon's discretion mainly based on his previous results. Therefore, we believe there is an imperative need to develop high quality studies based on accurate scientific evidence to universally establish valid guidelines for PR in TKA.

The Added Value of Point-Light Display Observation in Total Knee Arthroplasty Rehabilitation Program: A Prospective Randomized Controlled Pilot Study

Background and Objectives: The present study aimed to assess the potential benefit of the observation of rehabilitation-related point-light display in addition to a conventional 3-week rehabilitation program, the objective being to improve functional capacity in patients having undergone total knee arthroplasty. Materials and Methods: Patients randomized in the control group had conventional rehabilitation treatment with two sessions per day 5 days a week of physical therapy (90 min), whereas patients in the experimental group had a program of conventional rehabilitation combined with a point-light display observation two times per day (5 min) and 3 days a week. Results: The patients of both groups had improved their performances by the end of the program, and the pre- and post-test improvement were superior for the experimental group over the control group concerning the total WOMAC score (p = 0.04), the functional WOMAC score (p = 0.03), and correct recognition of point-light displays (p = 0.003). Conclusions: These findings provide new insight favoring systematic point-light display observation to improve functional recovery in patients with total knee arthroplasty.