The Oswestry Spinal Risk Index (OSRI): an external validation study.

Abstract

The Oswestry Spinal Risk Index (OSRI) was recently reported as an adjunct in the management of metastatic spinal disease. Based on the tumour type and a general condition score, survivorship is predicted. We aimed to externally validate this new score. We assessed the survivorship of 121 patients identified from a prospectively collated database in the National Spinal Injuries Unit in the Republic of Ireland. Actual survivorship was calculated according to the tumour subtype and general conditioning, according to the Karnofsky Performance Score (OSRI = Primary Tumour Pathology + (2-General Conditioning Score)). Our results were then compared to those previously published. 45.5 % were female (n = 55). The mean age at presentation was 61.5 years (range 23-85). Breast and prostate cancers were the most frequent diseases encountered. The actual survival in our cohort closely mirrored the predicted survival, according to the equation used to calculate the OSRI with an overall strong correlation found (r = 0.798, p = 0.001). We found that the OSRI is a simple to use scoring system. We found a strong correlation in our results with the predicted survivorship based on the OSRI. The OSRI can be used as a useful adjunct in the management of patient with metastatic disease of the spine.