Admission Norton scale scores (ANSS) are associated with post-operative complications following spine fracture surgery in the elderly

Abstract

We sought to determine if low ANSS, usually associated with high pressure ulcer risk, are also associated with post-operative complications following spine fracture surgery in the elderly. This was a retrospective cross-sectional study conducted at the division of orthopedic surgery in a tertiary medical center between January 2008 and October 2010. The medical charts of consecutive elderly (≥ 65 years) patients admitted for spine fracture surgery were studied for the following measurements: ANSS, demographic data, co-morbidities, and post-operative complications. Except for pressure ulcers, post-operative complications included: acute coronary syndrome, acute renal failure, confusion, pneumonia, urinary tract infection, venous thromboembolism, and wound infection. The final cohort included 90 patients: 66 (73.3%) females and 24 (26.7%) males. Mean age for the entire cohort was 78.9 ± 0.7 years. Most patients had lumbar fractures (n=49; 54.4%) or thoracal fractures (n=26; 28.9%). Most patients underwent kyphoplasty (n=65; 72.2%). Mean ANSS was 15.9 ± 0.3, and 29 (32.2%) patients had low (<15) ANSS. Patients with low ANSS had significantly more post-operative complications relative to patients with high ANSS (1.0 ± 0.2 vs. 0.2 ± 0.1; p<0.0001). Among all post-operative complications, urinary tract infection was independently associated with ANSS (p<0.0001). Binary regression analysis showed that ANSS were independently associated with post-operative complications (p=0.001). We conclude that low ANSS are associated with post-operative complications and urinary tract infection in particular, following spine fracture surgery in the elderly. Hence, the Norton scoring system may be used for predicting and preventing post-operative complications in this population.