Coccyx Flashcards
What is the number of coccygeal somites?
Ten
What is the typical number of segments that unite to form the adult coccyx?
4 segments
When is ossification of coccyx completed?
About age 30
What is the direction of fusion of coccygeal segments?
From caudal to cranial, the last segments to fuse together are Co1 and Co2
What is the direction of the coccygeal curve?
Posterior (kyphotic)
What is the major motion and range of motion for coccyx?
Flexion- extension, 5-20 degrees
How many coccygeal nerves are present in the fetus?
Typically 5 pairs of coccygeal nerves are present
What forms the coccygeal nerve plexus?
S4, S5, and Co1 nerves
What is the ganglion impar?
A midline sympathetic ganglion
What is the coccygeal glomus or coccygeal body?
An enlarged encapsulated arteriovenous anastomosis located near the last segment of coccyx
What innervates the coccygeal glomus or coccygeal body?
Both sympathetic and parasympathetic fibers are identified
What joint classifications are present for coccyx?
Cartilaginous (amphiarthrosis) symphysis and fibrous (amphiarthrosis) syndesmosis
What ligaments of the vertebral column will be attached to coccyx?
Anterior sacrococcygeal ligament, superficial posterior sacrococcygeal ligament, deep posterior sacrococcygeal ligament, posterior sacrococcygeal ligament, intercornual ligament, anococcygeal ligament, sacrospinous ligament, sacrotuberous ligament, short posterior sacro-iliac ligament, long posterior sacro-iliac ligament and intervertebral disc
