Results of total knee replacement with/without resurfacing of the patella

Comparison of clinical outcomes between patellar resurfacing and patellar non-resurfacing in cruciate retaining total knee arthroplasty

BACKGROUND

It is not established whether patellar resurfacing is better than patellar non-resurfacing during total knee arthroplasty (TKA). This study was to compare the clinical outcomes between groups with patellar resurfacing and non-resurfacing during cruciate retaining (CR) TKA.

METHODS

In this retrospective cohort study, subjects undergoing primary CR TKA for osteoarthritis between 2012 and 2019 were included. Of 500 subjects, 250 had patellar resurfacing (group 1) and 250 had patellar non-resurfacing (group 2) CR TKA. Knee society knee score (KSKS), knee society function score (KSFS), Western Ontario and McMaster Universities Osteoarthritis (WOMAC) scale, Kujala score, anterior knee pain, patellar compression test and range of motion (ROM) of the replaced knee were assessed and compared between the two groups.

RESULTS

There were no significant differences in KSKS, KSFS, WOMAC scale, Kujala score, prevalence of anterior knee pain and ROM of the replaced knee between the two groups at the last follow-up (p > .05). Group 2 had more subjects with positive patellar compression test than group 1 at the last follow-up (p = .010).

CONCLUSIONS

Clinical and functional outcomes of the replaced knee were not different between patellar resurfacing and non-resurfacing groups. Anterior knee pain was significantly reduced after total knee arthroplasty regardless of patellar resurfacing.

LEVEL OF EVIDENCE

Retrospective cohort study, Level III.

Patellar management during total knee arthroplasty: a review

The optimal management of the patella during total knee arthroplasty (TKA) remains controversial and surgeons tend to approach the patella with one of three general mindsets: always resurface the patella, never resurface the patella, or selectively resurface the patella based on specific patient or patellar criteria.

Studies comparing resurfacing and non-resurfacing of the patella during TKA have reported inconsistent and contradictory findings.

When resurfacing the patella is chosen, there are a number of available patellar component designs, materials, and techniques for cutting and fixation.

When patellar non-resurfacing is chosen, several alternatives are available, including patellar denervation, lateral retinacular release, and patelloplasty. Surgeons may choose to perform any of these alone, or together in some combination.

Prospective randomized studies are needed to better understand which patellar management techniques contribute to superior postoperative outcomes. Until then, this remains a controversial topic, and options for patellar management will need to be weighed on an individual basis per patient.

Cite this article: EFORT Open Rev 2021;6:861-871. DOI: 10.1302/2058-5241.6.200156

Functional Outcomes Following Total Knee Arthroplasty Without Patellar Resurfacing: A Minimum Two-Year Follow-Up Retrospective Cohort Study

This paper seeks to address the effectiveness of total knee arthroplasty (TKA) when performed without patellar resurfacing. The objective of this article is to investigate the effect of total knee arthroplasty without patellofemoral resurfacing on postoperative outcome.

All patients with degenerative knee osteoarthritis (OA) that underwent TKA without patellar resurfacing were included in the study. The clinical data of 163 patients, including 98 females and 65 males with a mean age of 63 years (range 54-78 years) were retrospectively analyzed from April 2008 to April 2011. Intraoperative cartilage degeneration according to Outerbridge classification criteria was as follows: 22 cases of grade I, 38 cases of grade II, 64 cases of grade III, 39 cases of grade IV. There were no significant differences in gender, age, and side differences between the patients at all levels (P > 0.05). The duration of tourniquet use and related complications were recorded. Knee function was assessed using the American Knee Society Scoring System (KSS) and the patellar score (PS). Patient satisfaction and knee pain were assessed by the pain visual analog scale (VAS). The evaluation was conducted using routine X-ray film to observe the position of the prosthesis and the patella. Statistical analysis used included a comparison between groups by analysis of variance (ANOVA) using the Student-Newman-Keuls (SNK) test and comparison of grade data using the rank-sum test.

The average tourniquet time was 125 minutes, with a range of 90-150 minutes. All the incisions healed with primary intention without early complications. All patients were followed for two to five years with an average of 3.6 years. At six months and at the last follow-up, the KSS and PS scores were significantly higher than those before surgery (P < 0.05). There was no significant difference between the sixth month and the last follow-up (P > 0.05). There were significant differences in preoperative KSS and PS scores between patients with different grades of cartilage degeneration (P < 0.05), but there was no significant difference at the last follow-up (P > 0.05). At the last follow-up, seven patients had persistent anterior knee pain, five patients had mild pain, and two patients had moderate pain according to the VAS assessment criteria. Patient satisfaction evaluation was as follows: 90 patients were very satisfied, 66 patients were satisfied, five patients were uncertain, and two patients were unsatisfied. There were no significant differences in satisfaction and knee pain between patients with different grades of patellofemoral degeneration (P > 0.05).

In conclusion, at six months and at the last follow-up, outcome measures for patients were significantly higher than before surgery for TKA without the use of patellar resurfacing and the majority of patients were satisfied with the outcome of the procedure. TKA continues to be a successful procedure without the use of patellar resurfacing.

Patellar Resurfacing in Total Knee Arthroplasty: Systematic Review and Meta-Analysis

BACKGROUND

Patellar resurfacing in total knee arthroplasty remains controversial. The aim of this study is to evaluate this technique through an analysis of comparative studies in the current literature.

METHODS

We performed a comprehensive search of PubMed, MEDLINE, Cochrane, CINAHL, and EMBASE databases using various combinations of the keywords "Knee," "Replacement," "Prosthesis," "Patella," "Resurfacing," and "Arthroplasty." All articles relevant to the subject were retrieved, and their bibliographies were hand searched for further references relevant to primary patellar resurfacing in total knee arthroplasty. Only articles published in peer-reviewed journals were included in this systematic review.

RESULTS

The percentage for a reoperation was 1% for the patellar resurfacing group (17/1636) and 6.9% for the non-resurfacing group (118/1699) (odds ratio [OR] 0.18, 95% confidence interval [CI] 0.11-0.29, P < .00001). The patellar resurfacing group showed a significantly higher postop Knee Society Score (KSS) pain (OR 1.52, 95% CI 0.68-2.35, P = .004) and postop Hospital for Special Surgery score (OR 4.35, 95% CI 3.21-5.49, P < .00001), over the non-resurfacing group.

CONCLUSION

Based on the outcome scores of KSS (pain), KSS (function), and Hospital for Special Surgery postop, patellar resurfacing TKAs have performed better than non-resurfaced TKAs. The lower secondary operation and revision rates for patellar resurfaced TKAs also demonstrate that this technique is the more effective option. However, the full impact of patellar resurfacing still needs to be critically evaluated by larger randomized controlled trials with long-term follow-up.

The role of patelloplasty in total knee arthroplasty

INTRODUCTION

Anterior knee pain (AKP) is a frequent complication after total knee arthroplasty (TKA). Patelloplasty, defined as reshaping the patella for optimal tracking in the trochlea, has been proposed to reduce the rate of this complication in patellar retaining implants. Aim of this study was to analyze the available literature regarding the outcomes of patelloplasty and to assess its methodological quality.

MATERIALS AND METHODS

A comprehensive review of the English literature was performed using the keywords "total knee arthroplasty", "patelloplasty" and "patellaplasty" with no limit regarding the year of publication. All the selected articles were evaluated with the Coleman score.

RESULTS

Seven full text articles were retrieved. The initial cohort included 461 knees in the study groups and 465 in the control groups. At an average FU of 70.6 months 447 knees were reviewed in the study group and 447 in the control groups. The global rate of AKP after patelloplasty was 11.3 % which compared to 7.9 % in the patella resurfacing control group. No signs of specific patellar complications due to patelloplasty were reported. Average Coleman score was 66.9.

CONCLUSION

Most of the literature has barely sufficient methodological quality. Patelloplasty aims at reducing patellar thickness and improve its tracking with TKA. This procedure is a safe and easy option with no reported adverse effects. In the included studies, outcome seemed to be superior in comparison with isolated osteophyte removal and denervation with a lower rate of AKP. The included studies, however, report a lower rate of AKP following TKA with patellar resurfacing. Patelloplasty may have the potential to improve the outcome of patellar retaining implants.

LEVEL OF EVIDENCE

4, systematic review.

Do surgical patellar interventions restore patellar kinematics in fixed-bearing, cruciate-retaining total knee arthroplasty?: An in vitro study

Despite different surgical patellar interventions, the decision how to treat the patella during TKA remains controversial. The purpose of this study was to quantify the effect of different reconstructive patellar interventions on patellar kinematics during TKA using optical computer navigation. We implanted ten navigated TKAs in full body specimens. During passive motion, the effect of different surgical patellar interventions on patellar kinematics was analysed. A contrarily tilt behaviour was observed in the TKA group without patellar intervention compared to the natural knee. Lateral release led to similar tilt values (P < 0.05). All surgical interventions led to a 3 to 5mm medial shift of the patella (P < 0.05). None of the analysed surgical patellar interventions could restore natural patellar kinematics after TKA.