Holdswoh classification of thoracolumbar spine fracture is based on how many columns of spine?

Surgery

Holdswoh classification of thoracolumbar spine fracture is based on how many columns of spine?

A tender swelling in submandibular triangle is mostly likely diagnosed as

In transfacial proportions, the face Is divided into how many segments:

Specific for Ankylosing spondylitis is true?