Discogenic low back pain (DLBP) accounts for 39% of chronic lower back pain (CLBP). Unfortunately, accurate diagnosis remains challenging, as clinical examination and magnetic resonance imaging (MRI) may be normal. Provocative Discography (PD) is one method of distinguishing DLBP from other back pain causes. Though technically safe it is considered to be an invasive procedure, and has been linked to latent acceleration of disc degeneration. It is thus reserved for surgical planning, leaving many patients definitely undiagnosed.
This dilemma, has prompted the development of various novel diagnostic approaches, such as intervertebral disc ultrasound, provocative electric vibration and the study of serological biomarkers. Though promising, perhaps the most useful diagnostic marker is the presence of a high intensity zone (HIZ) in the annulus in one of the discs in a CLBP patient. In this case, there is a positive predictive value (PPV) of 88- 90% that the lumbar disc is the pain generator.
It would appear however that the significance of the HIZ remains underappreciated and a poorly understood marker for the non-invasive diagnosis of DLBP.
This paper explores how symptoms, imaging, and examination findings when considered together, might further improve diagnostic accuracy of DLBP in a non-invasive manner.
Combined criteria are already in use for diagnosing of ankylosing spondylitis (AS) and rheumatoid arthritis (RA).
Though this series was small, the back pain symptom patterns and examination findings were consistent with a DLBP patterns anecdotally reported by pain clinicians experienced in discography.
Therefore the development of a more formal DLBP diagnostic system, using not only the presence of HIZ, but symptoms-examination and imaging findings may offer a more accurate diagnosis for CLBP sufferers who are not candidates for provocative discography.