Does obesity influence clinical outcome at nine years following total knee replacement?

• Published in: Journal of bone and joint surgery. British volume Vol. 94; no. 10; pp. 1351 - 1355
• Main Authors: COLLINS, R. A, WALMSLEY, P. J, AMIN, A. K, BRENKEL, I. J, CLAYTON, R. A. E
• Format: Journal Article
• Language: English
• Published: London British Editorial Society of Bone and Joint Surgery 01.10.2012
• Subjects: Adult; Aged; Aged, 80 and over; Arthroplasty, Replacement, Knee - adverse effects; Biological and medical sciences; Body Mass Index; Diseases of the osteoarticular system; Female; Humans; Male; Medical sciences; Metabolic diseases; Middle Aged; Obesity; Obesity - complications; Orthopedic surgery; Osteoarthritis, Knee - complications; Osteoarthritis, Knee - surgery; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Treatment Outcome; Obesity; Total knee arthroplasty; Orthopedic surgery; Prognosis; Treatment; Nutrition disorder; Nutritional status
• ISSN: 0301-620X; 2044-5377
• DOI: 10.1302/0301-620x.94b10.28894

A total of 445 consecutive primary total knee replacements (TKRs) were followed up prospectively at six and 18 months and three, six and nine years. Patients were divided into two groups: non-obese (body mass index (BMI) < 30 kg/m(2)) and obese (BMI ≥ 30 kg/m(2)). The obese group was subdivided into mildly obese (BMI 30 to 35 kg/m(2)) and highly obese (BMI ≥ 35 kg/m(2)) in order to determine the effects of increasing obesity on outcome. The clinical data analysed included the Knee Society score, peri-operative complications and implant survival. There was no difference in the overall complication rates or implant survival between the two groups. Obesity appears to have a small but significant adverse effect on clinical outcome, with highly obese patients showing lower function scores than non-obese patients. However, significant improvements in outcome are sustained in all groups nine years after TKR. Given the substantial, sustainable relief of symptoms after TKR and the low peri-operative complication and revision rates in these two groups, we have found no reason to limit access to TKR in obese patients.