Back to Search
Start Over
Influence of Body Mass Index (BMI) on Functional Improvements at 3 Years Following Total Knee Replacement: A Retrospective Cohort Study.
- Source :
- PLoS ONE; Mar2013, Vol. 8 Issue 3, p1-9, 9p
- Publication Year :
- 2013
-
Abstract
- Background: The number of patients presenting for total knee replacement who are classified as obese is increasing. The functional benefits of performing TKR in these patients are unclear. Aim: To assess the influence pre-operative body mass index has upon knee specific function, general health status and patient satisfaction at 3 years following total knee replacement. Design: Retrospective comparative cohort study using prospectively collected data from an institutional arthroplasty register. Methods: 1367 patients were assessed using the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and Medical Outcomes Trust Short Form-36 (SF-36) scores supplemented by a validated measure of satisfaction pre-operatively and subsequently at 1,2 and 3 year post-operatively. Comparisons were made by dividing the cohort into 4 groups based on body mass index (BMI) 18.5–25.0 kg/m<superscript>2</superscript> (n = 253);>25.0–30.0 kg/m<superscript>2</superscript> (n = 559);>30.0−35.0 kg/m<superscript>2</superscript> (n = 373);>35.0 kg/m<superscript>2</superscript> (n = 182). Results: Despite lower pre-operative, 1 and 3 year WOMAC and SF-36 scores patients with the highest BMIs >35.0 kg/m<superscript>2</superscript> experienced similar improvements to patients with a ‘normal‘ BMI (18.5–25.0 kg/m<superscript>2</superscript>) at 1 year (Difference in WOMAC improvement = 0.0 (95%CI −5.2 to 5.2), p = 1.00) and this improvement was sustained at up to 3 years (Difference in 1 year to 3 year improvement = 2.2 (95%CI: −2.1 to 6.5), p = 1.00). This effect was also observed for the SF-36 mental and physical component scores. Despite equivalent functional improvements levels of satisfaction in the >35.0 kg/m<superscript>2</superscript> group were lower than for any other BMI group (>35.0 kg/m<superscript>2</superscript> = 84.6% satisfied versus 18.5–5.0 kg/m<superscript>2</superscript> = 93.3% satisfied,p = 0.01) as was the proportion of patients who stated they would have the operation again (>35.0 kg/m<superscript>2</superscript> = 69.6% versus 18.5–25.0 kg/m<superscript>2</superscript> = 82.2%,p = 0.01). Conclusion: Obese and morbidly obese patients gain as much functional benefit from total knee replacement as patients with lesser body mass indexes. This benefit is maintained for up to 3 years following surgery. However, these patients are less satisfied with their knee replacement and almost a third would not have the operation again. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 19326203
- Volume :
- 8
- Issue :
- 3
- Database :
- Complementary Index
- Journal :
- PLoS ONE
- Publication Type :
- Academic Journal
- Accession number :
- 87681045
- Full Text :
- https://doi.org/10.1371/journal.pone.0059079