Leaving the Patella Unresurfaced Does Not Increase the Risk of Short-Term Revision Following Total Knee Arthroplasty: An Analysis from the American Joint Replacement Registry

Abstract

The benefit of patellar resurfacing in total knee arthroplasty (TKA) remains uncertain, with conflicting evidence regarding associated revision rates and clinical outcomes. Although initial studies have reported higher revision rates associated with unresurfaced patellae, recent evidence questions the necessity of routine patellar resurfacing. This study aimed to evaluate the risk of revision following TKA performed with and without patellar resurfacing using data from the American Joint Replacement Registry (AJRR).

The AJRR was queried for all patients aged 65 years and older undergoing elective TKA between January 2012 and March 2020 with a minimum 2-year follow-up. Cases were linked using supplemental Centers for Medicare and Medicaid data. Cases with hybrid fixation, highly constrained implants, and revision components were excluded. Patients were categorized into two groups: those with a resurfaced patella and those without. Cumulative incidence function (CIF) curves and cause-specific Cox models were utilized to assess all-cause revision risk, adjusting for sex, age, femoral design (cruciate retaining vs. posterior stabilized), fixation type (cemented vs. cementless), and Charlson Comorbidity Index.

Of the 390,304 TKAs with minimum 2-year follow-up in our cohort, 22,829 had no patellar resurfacing performed. Adjusted hazard ratios (HRs) revealed no significant difference in all-cause revision (HR = 0.96, 95% confidence interval [CI]: 0.81–1.13, p = 0.656), revision for mechanical loosening (HR = 1.61 [0.88, 2.93], p = 0.122), or revision for infection (HR = 1.02 [0.79, 1.33], p = 0.860) associated with patellar resurfacing status.

Our study found that patients with an unresurfaced patella do not face an increased short-term revision risk following TKA. These findings challenge the necessity of routine patellar resurfacing and underscore the importance of considering other factors, such as femoral design, patient comorbidities, and implant-related variables in revision risk stratification.

 

MissingLinkText

Keywords

total knee replacement - patellar resurfacing - revision total knee replacement - American Joint Replacement Registry

The benefit of routine patellar resurfacing after total knee arthroplasty (TKA) remains highly debated and is dependent on several factors, including preoperative patellofemoral pain, size and quality of patellofemoral cartilage, severity of patellar osteoarthritis, patellar tracking, and history of inflammatory arthritis,[1] with significant variation in practice. Proponents of leaving the patella unresurfaced also cite avoiding an increased risk of fracture, loosening, wear, avascular necrosis, soft tissue impingement, and patellar and quadriceps tendon ruptures associated with patellar resurfacing.[2] [3] [4] [5] While most surgeons in the United States and Australia opt for routine patellar resurfacing, it is performed less commonly in Asia and Europe, with only 2 to 3% of TKAs being routinely resurfaced in countries such as Sweden.[6] However, according to the American Joint Replacement Registry (AJRR), the popularity of leaving the patella unresurfaced is rapidly increasing in the US and has almost tripled in the last 10 years to 11.4% of TKAs performed in 2022.[7]

Several randomized controlled trials and meta-analyses investigating routine patellar resurfacing during index TKA have been conducted with contrasting findings. While earlier studies found no difference in revision rates, several recent analyses reported higher revision rates in patients with unresurfaced patellae.[4] [5] [8] [9] Though this may indicate that primary patellar resurfacing lowers the risk of subsequent revision, it is currently uncertain if this is a function of addressing patellar-specific pathology or a surgeon-level bias toward secondary patellar resurfacing in patients with persistent pain after TKA. While preliminary studies reported decreased peripatellar pain with resurfacing,[2] it has been found that TKAs with patellar resurfacing can also present with anterior knee pain due to multifactorial etiology.[10] [11] [12] Contrasting data from a few trials in patients undergoing bilateral TKA with and without patellar resurfacing have shown no difference in revision rates and pain relief at 10 years follow-up.[9] [13] [14] In addition, recent studies have reported no difference in anterior knee pain,[15] [16] [17] range of motion,[17] [18] gait,[19] and patient-reported outcome measures[17] [20] between resurfaced and unresurfaced patellae.

In addition to this conflicting literature, there is currently a paucity of evidence regarding patellar resurfacing based on nationwide data, which may allow for generalization across the current U.S. healthcare landscape. The AJRR may provide a unique opportunity to compare TKA outcomes with and without patellar resurfacing in the United States, particularly in the context of the increasing popularity of leaving the patella unresurfaced. The current study, therefore, aimed to determine if patellar resurfacing is independently associated with increased short-term revision risk following primary TKA using data from the AJRR.

Materials and Methods

Study Design

This study, in collaboration with the American Academy of Orthopaedic Surgeons Registry Analytics Institute, queried the AJRR for all primary TKA cases between January 2012 and March 2020. Only patients aged 65 years and older were selected for analysis to allow for linking to U.S. Centers for Medicare & Medicaid Services (CMS) data to supplement the collection of outcomes occurring outside AJRR reporting institutions, if applicable. Outcomes were captured through March 2022 to ensure a minimum 2-year follow-up. Patients with missing data on sex, fixation, and design, as well as cases with hybrid or reverse hybrid fixation, highly constrained implants, revision components, supplemental stem fixation, or augments, were excluded. Catalog numbers from each case were identified and used for classification into target component categories.

Each procedure identified in the AJRR was also assessed for linked revision surgery in either AJRR or CMS databases using four criteria: surgical date after the index procedure, matching patient IDs, matching surgical sites, and matching laterality. Laterality was inferred using the International Statistical Classification of Diseases and Related Health Problems Procedure Coding System (ICD-10-PCS) codes, or via Current Procedural Terminology (CPT) codes that were paired with an element that indicates laterality.

Data regarding age, sex, body mass index (BMI), Charlson comorbidity index (CCI), femoral component design (cruciate retaining [CR] or posterior stabilized [PS]), method of fixation (cemented or cementless), and patellar resurfacing were collected, as well as the indication for revision, if applicable. The outcomes considered were all-cause revision, revision for mechanical loosening, and revision for infection.

 

MissingLinkText

Data Analysis

Group characteristics were summarized using counts and percentages for categorical variables and mean and standard deviation (SD) and median and interquartile range (IQR) for continuous variables. Intergroup comparisons were performed using the Chi-Square test for categorical variables and the student's t-test or Wilcoxon Rank Sum Test as appropriate for continuous variables. Cause-specific Cox models were used to evaluate the association of patellar resurfacing with all-cause revision, revision due to mechanical loosening, and revision due to infection. All analyses were adjusted for age, sex, implant design (CR vs. PS), fixation technique (cemented vs. uncemented), and CCI. Hazard ratios (HRs) with 95% confidence intervals were reported, and group-specific cumulative incidence function (CIF) curves were generated. All analyses were conducted using SAS Enterprise Guide v.7.15 (SAS Institute Inc., Arlington, VA), and statistical significance was evaluated at p < 0.05.

 

MissingLinkText

 

MissingLinkText

Results

A total of 1,098,792 TKAs were identified from the AJRR, of which 462,586 TKAs had a minimum 2-year follow-up. After exclusion criteria, 390,304 TKAs were available for analysis ([Fig. 1]). Patellar resurfacing was performed in 367,475 TKAs, while the patella was not resurfaced in 22,829 TKAs. A cemented patellar component was used in 99.8% (n = 366,775) of cases, while an uncemented patellar component was used in 0.02% (n = 700) of cases. A higher proportion of the patients were women in both the resurfaced and unresurfaced groups (resurfaced: 60.66%, unresurfaced: 58.96%, p < 0.001). A higher percentage of posterior-stabilized designs were used with patellar resurfacing (resurfacing: 95.54% vs. non-resurfacing: 4.46%, p < 0.001) compared with cruciate-retaining designs (resurfacing: 92.60% vs. nonresurfacing: 7.40%, p < 0.001). Both comparison groups were similar in terms of age, BMI, and CCI. Group characteristics are reported in [Table 1].

Fig. 1 Flow chart demonstrating exclusion and allocation of primary TKA cases into cohorts: patellar resurfacing (cemented and cementless) and unresurfaced patella. AJRR, American Joint Replacement Registry; CR, cruciate retaining; PS, posterior stabilized; TKA, total knee arthroplasty.

Table 1 Characteristics of the study cohort

	Patella resurfaced		Total	p-Value
	Yes	No
	(N = 367,475)	(N = 22,829)	(N = 390,304)
Sex
Female	222,910 (60.66%)	013,460 (58.96%)	236,370 (60.56%)	<0.001
Male	144,565 (39.34%)	009,369 (41.04%)	153,934 (39.44%)
Age
Mean (SD)	73.14 (5.76)	73.17 (5.85)	73.14 (5.77)	0.47
Median (IQR)	72.1 (68.4–76.9)	72.1 (68.4–77.0)	72.1 (68.4–76.9)	<0.001
Age categories
65–74 y	242,497 (65.99%)	015,089 (66.10%)	257,586 (66.00%)	0.74
75+ y	124,978 (34.01%)	007,740 (33.90%)	132,718 (34.00%)
BMI
Mean (SD)	31.37 (6.26)	31.57 (6.18)	31.38 (6.25)	0.002
Median (IQR)	30.7 (27.0–35.0)	30.9 (27.1–35.3)	30.7 (27.0–35.0)	<0.001
N (N missing)	180,919 (239,582)	1,0137 (12,692)	191,056 (252,274)
BMI categories
<35	117,934 (74.60%)	007,417 (73.17%)	125,351 (74.51%)	0.001
35+	040,154 (25.40%)	002,720 (26.83%)	042,874 (25.49%)
Missing	209,387 (56.98%)	012,692 (55.60%)	222,079 (56.90%)
CCI
2 or less	109,655 (29.84%)	006,925 (30.33%)	116,580 (29.87%)	0.025
3 to 4	227,908 (62.02%)	014,151 (61.99%)	242,059 (62.02%)
5 or more	029,912 (8.14%)	001,753 (7.68%)	031,665 (8.11%)
Design
CR	170,655 (46.44%)	013,640 (59.75%)	184,295 (47.22%)	<0.001
PS	196,820 (53.56%)	009,189 (40.25%)	206,009 (52.78%)
Fixation
Cemented	352,151 (95.83%)	021,440 (93.92%)	373,591 (95.72%)	<0.001
Cementless	015,324 (4.17%)	001,389 (6.08%)	016,713 (4.28%)

Abbreviations: BMI, body mass index; CCI, Charlson comorbidity index; CR, cruciate retaining; IQR, interquartile range; PS, posterior stabilized; SD, standard deviation.

After adjusting for covariates such as age, sex, BMI, CCI, fixation technique, and implant design, there was no significant difference in the all-cause revision risk between resurfaced and unresurfaced patellae (HR = 0.96 [0.82, 1.13], p = 0.656). There were also no differences observed in terms of revision for mechanical loosening (HR = 1.61 [0.88, 2.93], p = 0.122) or infection (HR = 1.02 [0.79, 1.33], p = 0.860). However, PS knees (HR = 1.19, [1.1, 1.28], p < 0.001), increasing BMI (HR = 1.01 [1.01, 1.02], p < .001), and greater CCI (HR = 1.43 [1.44, 1.46], p < 0.001) were found to be associated with an increased all-cause revision risk on adjusted analysis, while female gender (HR = 0.81 [0.75, 0.87], p < .001) and younger patients (HR = 0.93 [0.92, 0.94], p < .001) had a lower risk of all-cause revision ([Table 2]). The CIF curves for all-cause, mechanical loosening-related, and infection-related revision-free survival are presented in [Figs 2], [3], and [4].

Table 2 Unadjusted and adjusted hazard ratios

Variable	Unadjusted		Adjusted
	HR (95% CI)	p-Value	HR (95% CI)	p-Value
All revisions
Uncemented vs. cemented	1.02 (0.92, 1.14)	0.649	1.07 (0.92, 1.24)	0.382
PS vs. CR femur	1.31 (1.26, 1.37)	<0.001	1.19 (1.1, 1.28)	<0.001
Patella resurfaced vs. unresurfaced	0.83 (0.76, 0.91)	<0.001	0.96 (0.82, 1.13)	0.656
Female vs. male	0.78 (0.75, 0.81)	<0.001	0.81 (0.75, 0.87)	<0.001
Patient BMI	1.02 (1.02, 1.03)	<0.001	1.01 (1.01, 1.02)	<0.001
Age	0.97 (0.96, 0.97)	<0.001	0.93 (0.92, 0.94)	<0.001
CCI	1.2 (1.18, 1.21)	<0.001	1.43 (1.4, 1.46)	<0.001
Revisions for mechanical loosening
Uncemented vs. cemented	0.91 (0.68, 1.23)	0.551	1.38 (0.9, 2.12)	0.14
PS vs. CR femur	1.69 (1.5, 1.9)	<0.001	1.51 (1.21, 1.89)	<0.001
Patella resurfaced vs. unresurfaced	1.18 (0.89, 1.56)	0.252	1.61 (0.88, 2.93)	0.122
Female vs. male	1.07 (0.95, 1.2)	0.242	1.15 (0.92, 1.44)	0.208
Patient BMI	1.01 (0.99, 1.03)	0.287	0.99 (0.97, 1.01)	0.316
Age	0.93 (0.92, 0.94)	<0.001	0.88 (0.86, 0.91)	<0.001
CCI	1.1 (1.05, 1.14)	<0.001	1.46 (1.36, 1.56)	<0.001
Revisions for infections
Uncemented vs. cemented	0.95 (0.8, 1.12)	0.528	1.01 (0.78, 1.29)	0.963
PS vs. CR femur	1.27 (1.19, 1.36)	<0.001	1.15 (1.02, 1.29)	0.023
Patella resurfaced vs. unresurfaced	0.92 (0.79, 1.07)	0.295	1.02 (0.79, 1.33)	0.86
Female vs. male	0.54 (0.51, 0.58)	<0.001	0.55 (0.49, 0.62)	<0.001
Patient BMI	1.03 (1.03, 1.04)	<0.001	1.03 (1.02, 1.04)	<0.001
Age	0.98 (0.97, 0.98)	<0.001	0.94 (0.93, 0.95)	<0.001
CCI	1.35 (1.32, 1.37)	<0.001	1.51 (1.47, 1.56)	<0.001

Abbreviations: BMI, body mass index; CCI, Charlson comorbidity index; CI, confidence interval; CR, cruciate retaining; HR, hazard ratio; PS, posterior stabilized.

Fig. 2 Cumulative incidence function curve for all-cause revision-free survival. CIF, cumulative incidence function.

Fig. 3 Cumulative incidence function curve for mechanical loosening-related revision-free survival. CIF, cumulative incidence function.

Fig. 4 Cumulative incidence function curve for infection-related revision-free survival. CIF, cumulative incidence function.

 

MissingLinkText

Discussion

The debate over patellar resurfacing in TKA has endured for decades and has been shaped by evolving surgical techniques, implant designs, and varying patient outcomes. Early studies suggested benefits with routine patellar resurfacing, including reduced anterior knee pain,[15] [16] [17] improved range of motion,[17] [18] and decreased revision rates.[19] However, recent evidence has challenged these assertions, prompting a reassessment of the necessity, outcomes, and clinical significance[15] [16] [17] [18] [19] [20] of routine patellar resurfacing.[10] [11] [12] In this analysis of AJRR data in patients aged 65 years and older, we found no difference in short-term all-cause revision, revision for mechanical loosening, or revision for infection between TKAs with resurfaced or unresurfaced patellae.

Previous studies using registry data have reported lower revision rates in TKA patients with resurfaced patellae. A study by Eiel et al. using AJRR data reported that unresurfaced patellae were more likely to require revision surgery.[21] Another Australian registry-based study found that TKAs performed without patellar resurfacing were four times more likely to require revision than TKAs in which the patella was resurfaced.[1] Yet these studies failed to control for the confounding risk factors described in this study. In contrast, the 2020 annual report from the Swedish National Arthroplasty Register indicated that the revision rates between resurfaced and unresurfaced TKAs were similar.[22] Similar findings were reported in a study conducted by Maney et al using data from the New Zealand Joint Registry.[23] While the reasons for these differences remain unclear, they may be influenced by regional variations in the preference for patellar resurfacing. Countries such as Norway (4%) and Sweden (0%) report significantly lower patellar resurfacing rates compared with the United States (89%) and Australia (76.1%), where the procedure is more commonly performed.[7] [24]

In this study, unadjusted analyses initially indicated lower revision rates with patellar resurfacing than when the patella was left unresurfaced. However, adjusted analyses found no statistically significant differences in the revision rates between knees with patellar resurfacing and those left unresurfaced, irrespective of the indication for revision (all-cause revision, revision due to mechanical loosening, or revision due to infection). This may be due to our analysis controlling for known nonmodifiable and modifiable risk factors such as age, sex, BMI, and CCI, as well as surgical variables, including component design and fixation technique, underscoring the importance of controlling for such confounding factors in further investigations. It has been widely reported that certain implant designs are associated with increased anterior knee pain, patella subluxation, and patellar erosion following surgery.[25] A study using New Zealand Arthroplasty Registry data reported implant design-specific differences in the incidence of all-cause revision across various patellar resurfacing strategies, although no differences in revision rates were observed between the various resurfacing strategies themselves.[23] Selective resurfacing performed in posterior-stabilized TKA was found to be associated with a lower incidence of revision, while it was associated with a greater incidence of revision with mobile-bearing TKA. Therefore, it is imperative to interpret the existing literature's findings in a design-specific context while selecting an appropriate resurfacing strategy in patients undergoing elective TKA.

The precise indications for patellar resurfacing also remain to be determined conclusively. Although various patients may benefit from this procedure, there are currently no established guidelines regarding when to resurface the patella. Consequently, surgical practice varies widely: some surgeons routinely resurface the patella, others do so selectively, and some avoid resurfacing altogether. While prior studies suggest that patellar resurfacing may be advantageous for certain patient populations,[15] [16] [17] this may not apply universally, particularly in patients at higher risk for extensor mechanism disruption. Patients with patellar abnormalities, such as patella baja or alta, abnormal patellar tracking, or comorbidities like diabetes, renal disease, obesity, or osteoporosis, may require additional consideration due to an increased risk of complications.[26] Although the current study did not assess the impact of patellar resurfacing strategies on short-term outcomes following TKA, future research should aim to identify specific patient groups who might derive a clear benefit from patellar resurfacing versus leaving the patella unresurfaced.

Our study's strengths lie in its robust methodology, drawing from a large, nationally representative dataset encompassing close to 400,000 patients. By addressing previous studies' limitations in controlling for confounding factors and the potential lack of generalizability of their findings, the current study provides a wider perspective on the impact of patellar resurfacing on revision risk following TKA. The inclusion of diverse practice settings inherent within the AJRR in our analysis enhances the external validity of our findings by reflecting broader contemporary TKA practices in the United States.[27] Despite these strengths, our study is not without its limitations. Being retrospective in nature, it is susceptible to selection bias inherent to registry data. Furthermore, while the AJRR offers unparalleled breadth in orthopedic data, the variability in surgeon expertise and practice patterns across contributing sites may introduce potential bias, though this diversity may also enhance generalizability.[28] In addition, this study only examined short-term revision risk, and longer follow-up may reveal differences in the risk of revision between resurfaced and unresurfaced patellae. Only patients aged 65 years and older were analyzed, and so, we are unable to comment on if differences in revision risk exist for younger patients. Additionally, given AJRR is not a government-mandated registry, it only captures a portion of the total U.S. volume of arthroplasty cases. Thus, only revision TKA cases are reported for those patients with linked CMS data for surgeries performed outside of AJRR reporting institutions, while other subsequent knee procedures such as arthroscopic lysis of adhesions and manipulation under anesthesia are currently not included in the dataset. We were also unable to compare cemented and cementless patellar components in our analysis, although the method of patellar fixation may impact revision risk. Finally, the current study only evaluated revision risk as an outcome. Future investigations exploring additional outcomes, including functional scores, patient satisfaction, and long-term implant survivorship, may provide a more cohesive interpretation of the impact of patellar resurfacing on primary TKA outcomes.

 

MissingLinkText

Conclusion

Our findings demonstrate that patellar resurfacing in TKA has a similar short-term risk of revision compared to leaving the patella unresurfaced, with a minimum 2-year follow-up. Continued research is required to evaluate patient factors and functional outcomes of TKA with and without patellar resurfacing to comprehensively assess which patient populations may benefit from patellar resurfacing versus those who may benefit from an unresurfaced patella in primary TKA.

 

MissingLinkText

 

MissingLinkText

Conflicts of Interest

None declared.

Note

The study was exempt from institutional review board approval.

• References

• 1 Clements WJ, Miller L, Whitehouse SL, Graves SE, Ryan P, Crawford RW. Early outcomes of patella resurfacing in total knee arthroplasty. Acta Orthop 2010; 81 (01) 108-113
• 2 Levai JP, McLeod HC, Freeman MAR. Why not resurface the patella?. J Bone Joint Surg Br 1983; 65 (04) 448-451
• 3 Meneghini RM. Should the patella be resurfaced in primary total knee arthroplasty? An evidence-based analysis. J Arthroplasty 2008; 23 (7, Suppl): 11-14
• 4 Delgado-González A, Morales-Viaji JJ, Arteaga-Hernández JG. et al. To resurface or not to resurface the patella in total knee arthroplasty, that is the question: a meta-analysis of randomized controlled trials. Medicina (Kaunas) 2022; 58 (02) 227
• 5 Johnson TC, Tatman PJ, Mehle S, Gioe TJ. Revision surgery for patellofemoral problems: should we always resurface?. Clin Orthop Relat Res 2012; 470 (01) 211-219
• 6 Abdel MP, Parratte S, Budhiparama NC. The patella in total knee arthroplasty: to resurface or not is the question. Curr Rev Musculoskelet Med 2014; 7 (02) 117-124
• 7 The American Joint Replacement Registry. Ann Rep 2023. Accessed on Aug 31, 2024. Available at: https://connect.registryapps.net/2023-ajrr-annual-report
• 8 Parvizi J, Rapuri VR, Saleh KJ, Kuskowski MA, Sharkey PF, Mont MA. Failure to resurface the patella during total knee arthroplasty may result in more knee pain and secondary surgery. Clin Orthop Relat Res 2005; 438 (438) 191-196
• 9 Longo UG, Ciuffreda M, Mannering N, D'Andrea V, Cimmino M, Denaro V. Patellar resurfacing in total knee arthroplasty: systematic review and meta-analysis. J Arthroplasty 2018; 33 (02) 620-632
• 10 Tang X, He Y, Pu S. et al. Patellar resurfacing in primary total knee arthroplasty: a meta-analysis and trial sequential analysis of 50 randomized controlled trials. Orthop Surg 2023; 15 (02) 379-399
• 11 Barrack RL, Wolfe MW, Waldman DA, Milicic M, Bertot AJ, Myers L. Resurfacing of the patella in total knee arthroplasty. A prospective, randomized, double-blind study. J Bone Joint Surg Am 1997; 79 (08) 1121-1131
• 12 Teel AJ, Esposito JG, Lanting BA, Howard JL, Schemitsch EH. Patellar resurfacing in primary total knee arthroplasty: a meta-analysis of randomized controlled trials. J Arthroplasty 2019; 34 (12) 3124-3132
• 13 Waters TS, Bentley G. Patellar resurfacing in total knee arthroplasty. A prospective, randomized study. J Bone Joint Surg Am 2003; 85 (02) 212-217
• 14 Lan RH, Bell JW, Samuel LT, Kamath AF. Evolving outcome measures in total knee arthroplasty: trends and utilization rates over the past 15 years. J Arthroplasty 2020; 35 (11) 3375-3382
• 15 Chen K, Dai X, Li L, Chen Z, Cui H, Lv S. Patellar resurfacing versus nonresurfacing in total knee arthroplasty: an updated meta-analysis of randomized controlled trials. J Orthop Surg Res 2021; 16 (01) 83
• 16 Dong Y, Li T, Zheng Z, Xiang S, Weng X. Adding patella resurfacing after circumpatellar electrocautery did not improve the clinical outcome in bilateral total knee arthroplasty in Chinese population: a prospective randomized study. J Arthroplasty 2018; 33 (04) 1057-1061
• 17 Burnett RSJ, Boone JL, McCarthy KP, Rosenzweig S, Barrack RL. A prospective randomized clinical trial of patellar resurfacing and nonresurfacing in bilateral TKA. Clin Orthop Relat Res 2007; 464: 65-72
• 18 Myles CM, Rowe PJ, Nutton RW, Burnett R. The effect of patella resurfacing in total knee arthroplasty on functional range of movement measured by flexible electrogoniometry. Clin Biomech (Bristol, Avon) 2006; 21 (07) 733-739
• 19 Smith AJ, Lloyd DG, Wood DJ. A kinematic and kinetic analysis of walking after total knee arthroplasty with and without patellar resurfacing. Clin Biomech (Bristol, Avon) 2006; 21 (04) 379-386
• 20 Campbell DG, Duncan WW, Ashworth M. et al. Patellar resurfacing in total knee replacement: a ten-year randomised prospective trial. J Bone Joint Surg Br 2006; 88 (06) 734-739
• 21 Eiel ES, Donnelly P, Chen AF, Sloan M. Outcomes and survivorships of total knee arthroplasty comparing resurfaced and unresurfaced patellae. J Arthroplasty 2023; 38 (07, Suppl 2): S227-S232
• 22 The Swedish Knee Arthroplasty Register. Ann Rep 2022. Accessed on Aug 31, 2024. Available at: https://registercentrum.blob.core.windows.net/sar/r/SAR_Annual-report-2023_EN-DS5gryeOB.pdf
• 23 Maney AJ, Koh CK, Frampton CM, Young SW. Usually, selectively, or rarely resurfacing the patella during primary total knee arthroplasty: determining the best strategy. J Bone Joint Surg Am 2019; 101 (05) 412-420
• 24 Fraser JF, Spangehl MJ. International rates of patellar resurfacing in primary total knee arthroplasty, 2004–2014. J Arthroplasty 2017; 32 (01) 83-86
• 25 Insall JN, Ranawat CS, Aglietti P, Shine J. A comparison of four models of total knee-replacement prostheses. J Bone Joint Surg Am 1976; Sep; 58 (06) 754-765
• 26 Ng J, Balcells-Nolla P, James PJ, Bloch BV. Extensor mechanism failure in total knee arthroplasty. EFORT Open Rev 2021; 6 (03) 181-188
• 27 Hegde V, Stambough JB, Levine BR, Springer BD. Highlights of the 2022 American Joint Replacement Registry Annual Report. Arthroplast Today 2023; 21: 101137
• 28 Porter KR, Illgen RL, Springer BD. et al. Is American Joint Replacement Registry data representative of national data? A comparative analysis. J Am Acad Orthop Surg 2022; 30 (01) e124-e130

Publikationsverlauf

Eingereicht: 06. September 2024

Angenommen: 13. November 2024

Accepted Manuscript online:
14. November 2024

Artikel online veröffentlicht:
02. Dezember 2024