Abstract
Background: Obesity is considered to be a contraindication for unicompartmental knee replacement (UKR). The aim was to study the impact of BMI on failure rate and clinical outcome of the Oxford mobile bearing UKR.
Method: Two thousand four hundred and thirty-eight medial Oxford UKRs were studied prospectively and divided into groups: BMI < 25 (n = 378), BMI 25 to < 30 (n = 856), BMI 30 to < 35 (n = 712), BMI 35 to < 40 (n = 286), and BMI 40 to < 45 (n = 126) and BMI ≥ 45 (n = 80).
Results: There was no significant difference in survival rate between groups. At a mean follow-up of 5 years (range 1–12 years) there was no significant difference in the Objective American Knee Society Score between groups. There was a significant (p < 0.01) trend with the Oxford Knee Score (OKS) and Functional American Knee Society Scores decreasing with increasing BMI. As there was an opposite trend (p < 0.01) in pre-operative OKS, the change in OKS increased with increasing BMI (p = 0.048). The mean age at surgery was significantly (p < 0.01) lower in patients with higher BMI.
Conclusions: Increasing BMI was not associated with an increasing failure rate. It was also not associated with a decreasing benefit from the operation. Therefore, a high BMI should not be considered a contra-indication to mobile bearing UKR.
Level of evidence :IV
Method: Two thousand four hundred and thirty-eight medial Oxford UKRs were studied prospectively and divided into groups: BMI < 25 (n = 378), BMI 25 to < 30 (n = 856), BMI 30 to < 35 (n = 712), BMI 35 to < 40 (n = 286), and BMI 40 to < 45 (n = 126) and BMI ≥ 45 (n = 80).
Results: There was no significant difference in survival rate between groups. At a mean follow-up of 5 years (range 1–12 years) there was no significant difference in the Objective American Knee Society Score between groups. There was a significant (p < 0.01) trend with the Oxford Knee Score (OKS) and Functional American Knee Society Scores decreasing with increasing BMI. As there was an opposite trend (p < 0.01) in pre-operative OKS, the change in OKS increased with increasing BMI (p = 0.048). The mean age at surgery was significantly (p < 0.01) lower in patients with higher BMI.
Conclusions: Increasing BMI was not associated with an increasing failure rate. It was also not associated with a decreasing benefit from the operation. Therefore, a high BMI should not be considered a contra-indication to mobile bearing UKR.
Level of evidence :IV
| Original language | English |
|---|---|
| Pages (from-to) | 461-465 |
| Journal | The Knee |
| Volume | 20 |
| Issue number | 6 |
| Early online date | 26 Oct 2012 |
| DOIs | |
| Publication status | Published - Dec 2012 |
Access to Document
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NOTICE: this is the author’s version of a work that was accepted for publication in The Knee. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in The Knee, 2013, DOI 10.1016/j.knee.2012.09.017