Lower back pain is one of the most frequent reasons for consultation in the general population,which may affect up to 80-85% of people throughout life and being the most disabling symptom in young or middle-aged individuals.Causes of lower back pain can be multiple, as well as the individual characteristics of each lesion,so their management should be individualized.Currently, management of these patients consists in control studies by plain radiography,CT and MRI.These techniques cannot reliably assess early bone fusion, except in cases where a bridge or bone ingrowth exists as a sign of complete fusion.Metabolic bone changes in the fused area may become apparent by nuclear medicine techniques before anatomic changes could be observed by these traditional imaging modalities.In this book,the most innovative techniques in 3-dimensional SPECT/CT reconstruction are richly explained.3D reconstructed images has important value as it gives us information about the spatial relationship of pathological focus of radiotracer uptake respect to osteosynthesis material, helping the surgeon identify more clearly the clinical relevance of focuses,and providing an overview of the regional anatomy.