Maradit-Kremers, J Arthroplasty 2017 - Is Selectively Not Resurfacing the Patella an Acceptable Practice in Primary Total Knee Arthroplasty?

Is Selectively Not Resurfacing the Patella an Acceptable Practice in Primary Total Knee Arthroplasty?

Maradit-Kremers, Sierra, et al.·J Arthroplasty·2017·36 citations

Background

To resurface or not to resurface the patella remains a controversy in total knee arthroplasty (TKA). The purpose of this study was to assess the long-term outcomes associated with selectively not resurfacing the patella.

Methods

This was a historical cohort study of 15,497 patients with 21,371 primary TKA procedures performed at a single institution between 1985 and 2010.
The cohort included 402 (2%) knees with unresurfaced patellae and 20,969 knees with all-polyethylene patellae designs.
Reasons for not resurfacing the patella were documented.
Multivariable Cox regression analyses were used to estimate the risk of complications and revisions among procedures with unresurfaced patellae.

Results

According to the surgeon, reasons for not resurfacing were normal cartilage (226, 56%), young patient (30, 8%), thin patella (53, 13%), and surgeons' choice (93, 23%).
In age, sex, and calendar year-adjusted analyses, the risk of complications (hazard ratio [HR]: 1.25, 95% confidence interval [CI]: 1.06, 1.46) and all-cause revisions (HR: 1.39, 95% CI: 1.02, 1.89) were significantly higher after TKA with unresurfaced patellae.
However, after adjusting for femoral component types and operative diagnoses, these associations were no longer significant.
The only group with significantly worse outcomes were those with a thin patellae with increased risk of complications (HR: 2.66, 95% CI: 1.70, 4.17) and revisions (HR: 5.94, 95% CI: 2.35, 15.02).
Yet, the excess risk in the thin patellae group was mainly due to infections, and not related to unresurfaced patellae.

Conclusions

Selectively not resurfacing the patella seemed to provide similar results compared with routine resurfacing.

Supplemental

Is Selectively Not Resurfacing the Patella an Acceptable Practice in Primary Total Knee Arthroplasty?

Maradit-Kremers, Sierra, et al.J Arthroplasty201736 citations

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Is Selectively Not Resurfacing the Patella an Acceptable Practice in Primary Total Knee Arthroplasty?

Maradit-Kremers, Sierra, et al.·J Arthroplasty·2017·36 citations

DOI·PubMed

Background

Methods

This was a historical cohort study of 15,497 patients with 21,371 primary TKA procedures performed at a single institution between 1985 and 2010.
The cohort included 402 (2%) knees with unresurfaced patellae and 20,969 knees with all-polyethylene patellae designs.
Reasons for not resurfacing the patella were documented.
Multivariable Cox regression analyses were used to estimate the risk of complications and revisions among procedures with unresurfaced patellae.

Results

According to the surgeon, reasons for not resurfacing were normal cartilage (226, 56%), young patient (30, 8%), thin patella (53, 13%), and surgeons' choice (93, 23%).
In age, sex, and calendar year-adjusted analyses, the risk of complications (hazard ratio [HR]: 1.25, 95% confidence interval [CI]: 1.06, 1.46) and all-cause revisions (HR: 1.39, 95% CI: 1.02, 1.89) were significantly higher after TKA with unresurfaced patellae.
However, after adjusting for femoral component types and operative diagnoses, these associations were no longer significant.
The only group with significantly worse outcomes were those with a thin patellae with increased risk of complications (HR: 2.66, 95% CI: 1.70, 4.17) and revisions (HR: 5.94, 95% CI: 2.35, 15.02).
Yet, the excess risk in the thin patellae group was mainly due to infections, and not related to unresurfaced patellae.

Conclusions

Selectively not resurfacing the patella seemed to provide similar results compared with routine resurfacing.

Background

Methods

This was a historical cohort study of 15,497 patients with 21,371 primary TKA procedures performed at a single institution between 1985 and 2010.
The cohort included 402 (2%) knees with unresurfaced patellae and 20,969 knees with all-polyethylene patellae designs.
Reasons for not resurfacing the patella were documented.
Multivariable Cox regression analyses were used to estimate the risk of complications and revisions among procedures with unresurfaced patellae.

Results

According to the surgeon, reasons for not resurfacing were normal cartilage (226, 56%), young patient (30, 8%), thin patella (53, 13%), and surgeons' choice (93, 23%).
In age, sex, and calendar year-adjusted analyses, the risk of complications (hazard ratio [HR]: 1.25, 95% confidence interval [CI]: 1.06, 1.46) and all-cause revisions (HR: 1.39, 95% CI: 1.02, 1.89) were significantly higher after TKA with unresurfaced patellae.
However, after adjusting for femoral component types and operative diagnoses, these associations were no longer significant.
The only group with significantly worse outcomes were those with a thin patellae with increased risk of complications (HR: 2.66, 95% CI: 1.70, 4.17) and revisions (HR: 5.94, 95% CI: 2.35, 15.02).
Yet, the excess risk in the thin patellae group was mainly due to infections, and not related to unresurfaced patellae.

Conclusions

Selectively not resurfacing the patella seemed to provide similar results compared with routine resurfacing.

Background

Methods

This was a historical cohort study of 15,497 patients with 21,371 primary TKA procedures performed at a single institution between 1985 and 2010.
The cohort included 402 (2%) knees with unresurfaced patellae and 20,969 knees with all-polyethylene patellae designs.
Reasons for not resurfacing the patella were documented.
Multivariable Cox regression analyses were used to estimate the risk of complications and revisions among procedures with unresurfaced patellae.

Results

According to the surgeon, reasons for not resurfacing were normal cartilage (226, 56%), young patient (30, 8%), thin patella (53, 13%), and surgeons' choice (93, 23%).
In age, sex, and calendar year-adjusted analyses, the risk of complications (hazard ratio [HR]: 1.25, 95% confidence interval [CI]: 1.06, 1.46) and all-cause revisions (HR: 1.39, 95% CI: 1.02, 1.89) were significantly higher after TKA with unresurfaced patellae.
However, after adjusting for femoral component types and operative diagnoses, these associations were no longer significant.
The only group with significantly worse outcomes were those with a thin patellae with increased risk of complications (HR: 2.66, 95% CI: 1.70, 4.17) and revisions (HR: 5.94, 95% CI: 2.35, 15.02).
Yet, the excess risk in the thin patellae group was mainly due to infections, and not related to unresurfaced patellae.

Conclusions

Selectively not resurfacing the patella seemed to provide similar results compared with routine resurfacing.