Abstract
Obesity is clearly a worldwide epidemic with significant social, healthcare and economic implications.
A clear association between obesity and the need for both hip and knee replacement surgery has been demonstrated. Specifically the presence of class 3 obesity (BMI > 40) increases the incidence of THA by 8.5 times, and the incidence of TKA by 32.7 times, compared with patients of normal weight.
Issues related to TJA in the morbidly obese include: Outcomes - There is a growing body of evidence to support the premise that patients undergoing either THA or TKA who are morbidly obese derive significant benefit from the surgical intervention. Specifically patient and disease specific outcome measures (WOMAC, SF-12, KSCRS, HSS) demonstrate equal change between preoperative and postoperative scores in those patients of normal weight compared to the morbidly obese cohort; Complications - It would appear that the rate of deep infection is increased in the morbidly obese, and that the greater the BMI, the greater the risk of infection. This is important to understand and appreciate preoperatively as the surgeon discusses the risk/benefit ratio of the operative intervention.
There is little debate that performing total joint arthroplasty in the morbidly obese is technically challenging and that the potential for increased perioperative morbidity, particularly in the form of infection is present. That being said, the realised benefit to the patient of the surgical intervention is significant, and denying surgery on the basis of obesity alone is not justified.
