Total Knee Arthroplasty in Obesity: In-Hospital Outcomes and National Trends

• Published in: The Journal of arthroplasty 2016-11, Vol.31 (11), p.2408-2414
• Main Authors: Woon, Colin Y.L., MD, Piponov, Hristo, MD, Schwartz, Brian E., MD, Moretti, Vincent M., MD, Schraut, Nicholas, BS, Shah, Ritesh, MD, Goldstein, Wayne, MD
• Format: Article
• Language: English
• Subjects: Aged; Arthroplasty, Replacement, Knee - statistics & numerical data; complications; Female; Hospitals; Humans; Length of Stay; Male; Middle Aged; obesity; Obesity - complications; Obesity, Morbid - epidemiology; Orthopedics; osteoarthritis; Patient Discharge; total knee arthroplasty; Treatment Outcome; United States - epidemiology
• ISSN: 0883-5403; 1532-8406
• DOI: 10.1016/j.arth.2016.04.028

Abstract Background Both the prevalence of obesity and the utilization rate of total knee arthroplasty are increasing. The rate and proportion of TKA performed in the setting of obesity/morbid obesity is increasing significantly over time. Methods Using ICD-9 codes, we searched the National Hospitals Discharge survey national database for patients admitted for primary TKA between 2001 to 2010. We then used ICD-9 codes for obesity (BMI 30-40kg/m2 ) and morbid obesity (BMI ≥ 40kg/m2 ) to select the obese cohorts. Results We found 29,694 non-obese, 2,645 obese and 1150 morbidly obese patients. There was an increase in each group over time. The rate of obesity/morbid obesity was strongly correlated with time. Obese and morbidly obese patients were more likely to be younger, female, diabetic and have Medicaid than non-obese patients. Obese and morbidly obese patients had shorter hospital stays, and higher home discharge rates than non-obese patients. Obese and morbidly obese patients had lower transfusion rates, shorter hospital stays, and no increase in inpatient wound infection or venous thromboembolic complications than non-obese patients. The Midwest region saw a greater burden of obese TKA patients. Conclusion With the right measures and precautions, satisfactory in-hospital outcomes are possible in the obese patient following primary TKA. A limitation of this study is short in-hospital stay of the index procedure as complications may present later following discharge.