Lumbar region
Regio lumbalis
Definition
The lumbar region corresponds to the dorsal and lateral portion of the trunk located between the thoracic cage and the pelvic area, at the level of the lumbar vertebrae. It forms the central part of the back.
Anatomically, this region includes the lumbar vertebrae and their transverse processes, the erector spinae muscles, the dorsal abdominal muscles (internal oblique, external oblique, and transversus abdominis), and it overlies internal organs such as the kidneys and part of the large intestine depending on the species.
The morphology of the lumbar region varies among species: in dogs and cats, it is flexible and mobile, allowing a wide range of motion; in ruminants, it is more rigid, adapted for weight-bearing and stability; in horses, it is long and powerful but relatively inflexible; in humans, it forms the lower back, composed of five massive vertebrae adapted to upright posture and load-bearing.
References
Dyce KM, Sack WO, Wensing CJG. Textbook of Veterinary Anatomy. 5th ed. St. Louis: Elsevier; 2017.
König HE, Liebich HG, editors. Veterinary Anatomy of Domestic Mammals: Textbook and Colour Atlas. 6th ed. Stuttgart: Thieme; 2020.
Evans HE, de Lahunta A. Miller’s Anatomy of the Dog. 4th ed. St. Louis: Elsevier; 2013.
