1.0Best Spine Hospitalshttps://www.bestspinehospitals.com/blogdrspinehttps://www.bestspinehospitals.com/blog/author/drspine/L1: Definition, Uses, and Clinical Overview - Best Spine Hospitalsrich600338<blockquote class="wp-embedded-content" data-secret="mZioohuUFq"><a href="https://www.bestspinehospitals.com/blog/l1-definition-uses-and-clinical-overview/">L1: Definition, Uses, and Clinical Overview</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://www.bestspinehospitals.com/blog/l1-definition-uses-and-clinical-overview/embed/#?secret=mZioohuUFq" width="600" height="338" title="“L1: Definition, Uses, and Clinical Overview” — Best Spine Hospitals" data-secret="mZioohuUFq" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script type="text/javascript">
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L1 most commonly refers to the first lumbar vertebra in the lower back. It can also refer to the L1 spinal nerve and related dermatome (skin area) and myotome (muscle group). Clinicians use “L1” as an anatomic label in exams, imaging reports, and spine procedures. It is a key landmark at the thoracolumbar junction, where the thoracic spine transitions to the lumbar spine.