Mechanisms of low back pain: a guide for diagnosis and therapy

Abstract

Chronic low back pain (CLBP) is a chronic pain syndrome in the lower back region, lasting for at least 3 months. CLBP represents the second leading cause of disability worldwide being a major welfare and economic problem. The prevalence of CLBP in adults has increased more than 100% in the last decade and continues to increase dramatically in the aging population, affecting both men and women in all ethnic groups, with a significant impact on functional capacity and occupational activities. It can also be influenced by psychological factors, such as stress, depression and/or anxiety. Given this complexity, the diagnostic evaluation of patients with CLBP can be very challenging and requires complex clinical decision-making. Answering the question "what is the pain generator" among the several structures potentially involved in CLBP is a key factor in the management of these patients, since a mis-diagnosis can generate therapeutical mistakes. Traditionally, the notion that the etiology of 80% to 90% of LBP cases is unknown has been mistaken perpetuated across decades. In most cases, low back pain can be attributed to specific pain generator, with its own characteristics and with different therapeutical opportunity. Here we discuss about radicular pain, facet Joint pain, sacro-iliac pain, pain related to lumbar stenosis, discogenic pain. Our article aims to offer to the clinicians a simple guidance to identify pain generators in a safer and faster way, relying a correct diagnosis and further therapeutical approach.

Keywords: CLBP; back; low back pain; spine.

Figure 1.. MRI sagittal image showing an abnormal alignment of lumbar vertebrae; black discs (red arrow) are pathogenetic for discogenic pain; facet joint hypertrophy (yellow arrow) is pathogenetic for facet joint pain.

Figure 2.. MRI axial image showing reduction in the size of the spinal canal (blue arrow), a pathogenetic finding in spinal stenosis; the red arrow shows radicular compression that can cause radicular pain.