Possible pathogenic mechanism of gluteal pain in lumbar disc hernia.

Recent reported results by Fang et al. published in BMC Musculoskeletal Disorders have added to the weight of evidence supporting association between gluteal pain and lumbar disc hernia. Their clinical finding shows the L4/5 level is the main level responsible for gluteal pain in lumbar disc hernia. Indeed, many possible mechanisms may explain why patients experience pain in the gluteal area. In this Correspondence, we would like to highlight several possible mechanisms of LDH-related gluteal pain based on detailed analysis of the sensory innervation of the gluteal region. We hope this can better explain the phenomenon found by Fang et al. We believe the principle mechanism is compression/irritation of L5 or S1 dorsal rami (intraspinal portion), which produce gluteal pain by irritating superior/medial cluneal nerve and referred pain from facet joints and sacroiliac joints. In addition, the presence of proximal sciatica could also induce gluteal pain. Lastly, fibers in the superior or inferior gluteal nerve could be compressed/irritated in LDH, inducing LDH-related gluteal pain. However, additional studies are needed in the future to delineate the exact mechanism(s).