Insertion: Which muscle inserts on the transverse processes of the lumbar vertebrae?

Insertion: Which muscle inserts on the transverse processes of the lumbar vertebrae?

• A. Longissimus capitis
• B. Iliocostalis lumborum
• C. Splenius cervicis
• D. Longissimus cervicis

Answer: (B)

Understanding where back muscles attach helps explain their actions. The iliocostalis group sits along the side of the spine and has distinct insertion points. The iliocostalis lumborum starts from the iliac crest and sacral area and its fibers ascend to insert into the transverse processes of the lumbar vertebrae (as well as the lower ribs). That specific attachment to the lumbar transverse processes is what ties it to the question. The other muscles listed attach elsewhere: longissimus cervicis goes to the transverse processes of the cervical vertebrae, longissimus capitis reaches the skull near the mastoid, and splenius cervicis attaches to the transverse processes of the upper thoracic and cervical vertebrae. So, the muscle that inserts on the transverse processes of the lumbar vertebrae is the iliocostalis lumborum.

Understanding where back muscles attach helps explain their actions. The iliocostalis group sits along the side of the spine and has distinct insertion points. The iliocostalis lumborum starts from the iliac crest and sacral area and its fibers ascend to insert into the transverse processes of the lumbar vertebrae (as well as the lower ribs). That specific attachment to the lumbar transverse processes is what ties it to the question.

The other muscles listed attach elsewhere: longissimus cervicis goes to the transverse processes of the cervical vertebrae, longissimus capitis reaches the skull near the mastoid, and splenius cervicis attaches to the transverse processes of the upper thoracic and cervical vertebrae. So, the muscle that inserts on the transverse processes of the lumbar vertebrae is the iliocostalis lumborum.