ländryggen

Ländryggen, or the lumbar region, refers to the lower part of the back between the thoracic spine and the pelvis. In humans it largely corresponds to the area of the lumbar spine and the surrounding muscles and ligaments, and it bears much of the body's weight during standing and movement.

Anatomy and structure

The lumbar region contains five lumbar vertebrae, designated L1 through L5, and their intervertebral discs. The vertebrae articulate with each other via facet joints and connect to the sacrum at the lumbosacral junction (L5-S1). Muscles in the region include the erector spinae group and the quadratus lumborum, with the psoas major forming part of the deep anterior support. The thoracolumbar fascia and several ligaments, such as the posterior and anterior longitudinal ligaments, provide additional stability. The lumbar spine houses the lower spinal nerves (L1–L5) and contributes to the cauda equina below the conus medullaris.

Function

The ländryggen supports body weight, stabilizes the trunk, and allows movements such as forward bending, backward bending, and side bending, with limited rotation. It helps protect neural structures at the end of the spinal cord and serves as an attachment point for muscles that control posture and locomotion.

Clinical relevance

Low back pain is a common condition associated with the lumbar region. Issues include degenerative changes, lumbar disc herniation, and radiculopathy when nerve roots are irritated (often at L4–L5 or L5–S1). Diagnosis relies on clinical evaluation and imaging as needed. Treatments range from physical therapy and medications to injections or, in selected cases, surgical interventions such as discectomy or fusion.