Longissimus Thoracis Muscle

Description

Centered on the posterior trunk of an adult female, the longissimus thoracis is highlighted as the lateral column of the erector spinae, running parallel to the spinous processes and immediately lateral to the intermediate spinalis and the deeper multifidus. Superiorly it ascends toward the thoracic region beneath the overlying trapezius, while inferior fibers blend with the thoracolumbar fascia and arise from the lumbar transverse processes and posterior iliac crest region. Laterally, the muscle belly approaches the angles of the ribs, with segmental slips spanning from transverse processes to adjacent ribs, and it sits medial to the more superficial latissimus dorsi along the posterolateral back. Clinically, this view matters because the longissimus thoracis is a frequent generator of axial low back pain and thoracolumbar myofascial trigger points, and its bulk and tone strongly influence lumbar lordosis and extension control during lifting. Palpation and injection planning often target the paraspinal gutter just lateral to the spinous processes, and the illustration clarifies why deeper needles risk contacting the transverse processes before reaching the plane of multifidus. Spine surgery also cares: posterior midline approaches strip the erector spinae from the laminae, while muscle-splitting or Wiltse approaches exploit the natural plane between multifidus and longissimus to reduce denervation and postoperative atrophy. Use this artwork in anatomy and kinesiology courses covering the erector spinae, in physical therapy texts on lumbar stabilization and paraspinal palpation, and in orthopedic or neurosurgical teaching files comparing posterior approaches to the thoracolumbar spine. A strong reference for labeling longissimus thoracis in female back anatomy plates and patient-facing rehabilitation materials. Anatomical accuracy verified by SciePro's Medical Advisory Board.