Nonspecific back pain refers to pain that occurs without any known specific cause. The term can also be used to refer to back pain that arises from multiple causes simultaneously making it near impossible to determine what the primary cause of the pain is. This term only exists because of the inadequacy of medical diagnostic procedures and technology.

One of the reasons why back can be so non-specific is that the back has many moving parts most of which are pain sensitive. The appearance of the spine on advanced imaging studies such as computerized tomography (CT) and magnetic resonance imaging (MRI) does not always correlate with the presence of symptoms such as pain.

A comprehensive battery of tests may help uncover the cause of non-specific back pain in many cases, but in a small number of cases, the real causative factor(s) may be impossible to ascertain.