Association of Fatty Infiltration in Paraspinal Muscles With the Analgesic Effect of Lumbar Erector Spina Plane Block

Low back pain (LBP) is a common health problem that causes global disability. Lumbosacral radiculopathy (LR) is the most common cause of low back pain. Disc herniation is the most common cause of LR, in addition to spinal stenosis, foraminal stenosis, facet joint hypertrophy, and degenerative disease (1). Treatment options for lumbar disc herniation include conservative treatment, interventional pain management, and surgery. Lumbar erector spinae plane block (ESPB) is an interventional procedure for chronic axial and radicular low back pain which that is unresponsive to conservative treatment.

Lumbar paraspinal muscles play an important role in maintaining lumbar spine stability. Increased fat infiltration in the paraspinal muscles has been associated with high-intensity low back pain and poor functional status, and fat infiltration in the paraspinal muscles can be detected by lumbar magnetic resonance imaging. In this study, fatty infiltration in the bilateral lumbar multifidus muscles was evaluated at the L3 level using Goutallier classification.

The primary aim of this study was to investigate the potential relationship between the treatment outcome of lumbar ESPB and the degree of fatty infiltration in the paraspinal muscles in patients with chronic axial and/or radicular low back pain unresponsive to conservative treatments. The secondary aim was to identify other factors that may be associated with a successful response to lumbar ESPB and fatty infiltration of the paraspinal muscles.