Multifidus Muscle, Gross Anatomy

Description

Posterior trunk anatomy is rendered to emphasize the multifidus muscle in a male, layered deep to the erector spinae and arranged as short, obliquely oriented fascicles spanning adjacent vertebral segments. Along the midline, the spinous processes form the medial boundary, while the multifidus bellies thicken in the lumbar region and taper superiorly toward the thoracic spine, where ribs project laterally from the vertebrae. Superficially, the paired erector spinae columns flank the vertebral column, and the scapulae sit posterolaterally over the upper thorax; inferiorly, the sacrum and posterior pelvis anchor the lumbosacral junction. Segmental orientation matters here. Multifidus provides fine control of intervertebral motion and resists shear at the lumbar spine, a point that becomes clinically visible in mechanical low back pain and in postoperative deconditioning, where multifidus atrophy and fatty infiltration are commonly discussed after lumbar disc herniation or posterior decompression. Palpation, dry needling, and ultrasound-guided rehabilitation often target the lumbar multifidus medial to the longissimus, while pain procedures such as lumbar medial branch blocks and radiofrequency ablation depend on understanding the posterior elements and the relationship of paraspinal muscles to the facet joints. Use this artwork in gross anatomy teaching on the intrinsic (deep) back muscles, in physiotherapy and sports medicine materials on lumbar stabilization, or in spine surgery and interventional pain publications that need a clear posterior map of paraspinal layers relative to the vertebrae, ribs, scapulae, and pelvis. Clean landmarks. Anatomical accuracy verified by SciePro's Medical Advisory Board.