Multifidus Muscle Under the Skin

Description

Running deep to the erector spinae group, the multifidus is rendered as a series of short, obliquely oriented fascicles spanning from the sacrum and posterior iliac crest region to the spinous processes of the lumbar, thoracic, and lower cervical vertebrae. A posterior view of the male upper back and neck places the vertebral column on the midline, with multifidus positioned medial to the longissimus and iliocostalis and immediately lateral to the spinous processes. Superficially, the trapezius and posterior deltoid contour the shoulder girdle, while latissimus dorsi frames the lower posterior trunk. Depth is the point. Segmental anatomy of multifidus matters because its short fiber length and multisegment attachments make it a primary stabilizer of individual motion segments, a concept often tested in spine biomechanics and motor control teaching. Clinically, selective multifidus atrophy and fatty infiltration are common on MRI in chronic low back pain and after lumbar surgery, and this posterior layering helps explain why ultrasound-guided or exercise-based reactivation targets deep medial paraspinals rather than the more superficial erector spinae. Surgeons also rely on these relationships during midline posterior approaches to the lumbar spine, where subperiosteal elevation from the spinous processes and lamina risks denervating medial paraspinal musculature. Use this artwork in musculoskeletal anatomy courses to teach posterior trunk layering from trapezius and latissimus dorsi down to the transversospinalis group, or in spine-focused modules discussing segmental stabilization and postoperative muscle change. It also fits well in rehabilitation texts, pain medicine presentations, and journal figures illustrating paraspinal anatomy, vertebrae landmarks, and the sacrum-to-cervical distribution in an adult male. Anatomical accuracy verified by SciePro's Medical Advisory Board.