The Difficulties of Nutritional Assessment in Major Hip Surgery

There are many factors affecting the outcome of major hip surgery. One postulated factor is the patient’s peri-operative nutritional status. Several papers have confirmed the benefits of dietary supplements for malnourished patients. Despite this, there are currently no guidelines as to how best to assess nutrition in orthopaedic patients.

The aim of this study was to find a simple diagnostic test that accurately reflects nutritional status in patients undergoing major hip surgery. Twentyfive patients with fracture neck of femur and 25 total hip replacement patients were assessed. Nutritional risk assessment scores, body mass index (BMI), anthropometric and biochemical tests were applied. The different indices were correlated. Length of hospital stay was used as a measure of morbidity.

The correlations between the individual indices of nutritional status were disappointingly low. The only significant correlations for the Total Hip Arthroplasty group were BMI to triceps skinfold thickness (r_s=0.769, 95%CI: 0.505 to 0.900, p=0.0001) and BMI to skeletal muscle mass (r_s=0.501,95%CI: 0.092 to 0.766, p=0.018). The assessment of BMI is in practice very difficult in patients with fractures of the neck of the femur. There were no statistically significant correlations between any of the nutritional indices measured and postoperative morbidity.

This study was unable to accurately assess nutritional status in patients undergoing major hip surgery. A simple nutritional assessment that can be used on a busy orthopaedic ward has not been identified.