Coccyx consists of 3-5 vertebrae that fuse together by age 30. It's an inverted triangle with base at top and apex at bottom. Usually contains 4 coccygeal vertebrae (Co1-Co4). Can vary in number from 3 to 5 vertebrae
L5-S1 segment bridges lumbar and sacral spine, transferring loads to pelvis. Disc herniation occurs when nucleus pulposus protrudes through annulus fibrosus. Lumbar spine consists of 5 vertebrae (L1-L5) supporting upper body
Uncomfortable electrical sensation running down back and limbs. Can feel up or down spine, sometimes painful. Often elicited by bending head forward. Named after French neurologist Jean Lhermitte
CES occurs when nerves below spinal cord end are damaged. Main symptoms include severe back pain, saddle anesthesia, and bowel/bladder control loss. Can present with sciatica, weakness in lower legs, and sexual dysfunction
Tarlov cysts are CSF-filled sacs located in sacral region of spinal cord. Named after American neurosurgeon Isadore Tarlov, who described them in 1938. Most commonly found between S1 and S4/S5, rarely in cervical or thoracic spine
DISH is a common condition characterized by bony proliferation at tendinous and ligamentous insertion sites. Most common in thoracic spine, affecting 6th-7th decades with male predominance. Estimated prevalence ranges from 3-42%, with higher prevalence in developed countries