Nutritional Status and Arthroplasty: Malnutrition and Obesity

Malnutrition is common in patients undergoing primary total hip arthroplasty (13.9%) or primary total knee arthroplasty (17.8%). The prevalence is even higher in patients undergoing revision joint arthroplasty, especially in patients undergoing revision for an infection. The prevalence of obesity among patients undergoing primary and revision THA and TKA is increasing and higher than the national prevalence for the same time period. Malnutrition is often present in these obese patients. Serologic markers for malnutrition are associated with the development of postoperative complications in primary TJA. Obesity is a significant risk factor for severe osteoarthritis progressing to need for arthroplasty and obese patients with TJA are at an increased risk for immediate and long-term postoperative complications. Malnutrition can be diagnosed using laboratory values (albumin, total lymphocyte count, and transferrin), anthropometric measurements, and standardized scoring tools. BMI is commonly used to classify overweight and obese adults, but it actually measures excess weight and is only a surrogate measure of body fatness. In malnourished patients, some studies demonstrated that protein and vitamin D supplementation significantly improved outcomes after TJA. In obese adults, weight loss can be achieved through different methods, but it remains questionable if changes in BMI would truly affect arthroplasty outcomes.