The lumbar vertebrae

How they differ along the set

What changes from one end of the series to the other, which is most of what there is to know about any one of them.

• Seven, with bodies longer than those of the thoracic vertebrae.Miller 2020, p. 279
• They widen steadily through the series, and lengthen through the first five or six; the body of the seventh is about as long as that of the first.Miller 2020, p. 279
• The spines are tallest and heaviest in the middle of the loin, about half as long and twice as broad across the top as those at the front of the chest, and they lean slightly forwards.Miller 2020, p. 284
• The transverse processes point forwards and a little down, and are longest in the middle of the loin; in a thin dog their broad ends can be felt through the skin.Miller 2020, p. 284
• Accessory processes are well made on the first three or four and gone by the fifth or sixth.Miller 2020, p. 284
• The articular processes lie mostly in sagittal planes, and the caudal ones sit between the cranial ones of the vertebra behind, which is what checks side-to-side bending.Miller 2020, p. 284
• Every cranial articular process carries a mamillary process.Miller 2020, p. 284
• Thoracic and lumbar together come to twenty, and that number barely varies: of three hundred dogs, one had twenty-one.Miller 2020, p. 284

Named parts

What a member of this set carries, and what each part is called in the Nomina Anatomica Veterinaria.

BodyCorpus vertebrae

The block the vertebra is built on, waisted in the middle, convex in front and hollowed behind.Miller 2020, p. 260

Vertebral archArcus vertebrae

The two pedicles and two laminae that roof the spinal cord.Miller 2020, p. 260

Spinous processProcessus spinosus

The single blade on top, where the laminae meet.Miller 2020, p. 261

Transverse processProcessus transversus

The arm reaching sideways where the pedicle leaves the body.Miller 2020, p. 261

Cranial vertebral notchIncisura vertebralis cranialis

The shallow step in the front edge of the arch.Miller 2020, p. 261

Caudal vertebral notchIncisura vertebralis caudalis

The deep step behind it; the two notches of neighbouring vertebrae make the intervertebral foramen the spinal nerve leaves by.Miller 2020, p. 261

Mamillary processProcessus mamillaris

The knob on every cranial articular process.Miller 2020, p. 284

Accessory processProcessus accessorii

The spur reaching back beside the articular processes of the next vertebra, on the first three or four only.Miller 2020, p. 284

The members

In order along the set. Any one of them can be singled out in the model above, with the picker beneath it.

• Lumbar vertebra IVertebra lumbalis I
• Lumbar vertebra IIVertebra lumbalis II
• Lumbar vertebra IIIVertebra lumbalis III
• Lumbar vertebra IVVertebra lumbalis IV
• Lumbar vertebra VVertebra lumbalis V
• Lumbar vertebra VIVertebra lumbalis VI
• Lumbar vertebra VIIVertebra lumbalis VII

References

Where to read this set in full, and where everything above was read.

• Miller 2020Miller 2020, ch. 4 The Skeleton, Lumbar Vertebrae, PDF p. 279
• König & Liebich 2020vertebral column, p. 109
• Dyce 2017ch. 12 Neck, Back and Vertebral Column of the Dog and Cat, p. 390 (anticlinal T11, p. 393-394)
• NAV 2017Osteologia