[Nutritional, bone and body composition assessment of patients with knee and hip arthroplasty].

Introduction: malnutrition, both due to deficiency and excess of nutrients, correlates to the morbidity of the surgical patient. Objectives: to analyze the nutritional status, body composition and bone health of patients undergoing elective knee and hip arthroplasty. Methods: an observational cross-sectional study was carried out evaluating patients undergoing hip and knee replacement surgery from February to September 2019. The Malnutrition Universal Screening Tool (MUST), anthropometry, hand-grip dynamometry, bone densitometry, lumbar spine X-ray and bioimpedance analysis were performed. Results: eighty-six patients (61.6 % women) were evaluated, with a mean age of 69.5 ± 9.5 years. The mean body mass index (BMI) was 31.3 ± 4.5. According to MUST, 21.3 % were at risk of malnutrition; 16.9 % had decreased triceps skinfold with respect to p50 and 20 % had a pathological hand-grip dynamometry. In 91.4 %, vitamin D was < 30 pg/ml. In the bioimpedanciometry, the women presented significantly decreased muscle mass values. Age was correlated with a lower presence of fat-free mass, total and appendicular muscle mass. In those over 65 years of age, 52.6 % of men vs 14.3 % of women had a decreased muscle mass index; 58.5 % had low bone mineral density. We observed vertebral bone collapses in 13.9 %. Conclusion: there is a high prevalence of obesity in patients who are candidates for arthroplasty and this does not exclude the existence of a risk of malnutrition. They may also have decreased muscle mass and strength. Nutritional education and physical exercise recommendations are essential in order to optimize nutritional status for surgery.