Pisiform

The pisiform bone (also called pisiform or lentiform bone) is a small, pea-shaped carpal bone found in the proximal row of the carpus. It is located where the ulna joins the carpus (wrist). It articulates only with the triquetral.

It is a sesamoid bone.

Surfaces and Articulations

Its dorsal surface presents a smooth, oval facet, for articulation with the triquetral.

The palmar surface is rounded and rough, and gives attachment to the transverse carpal ligament, flexor carpi ulnaris, abductor digiti quinti.

The lateral and medial surfaces are also rough, the former being concave, the latter usually convex.

Radiculopathy

The term radiculopathy refers to describe pain, and other symptoms like numbness, tingling, and weakness in your arms or legs caused by a irritation or compression of nerve roots.

This term comes from a combination of the Latin word “radix,” which means the roots of a tree, and  “pathos,” which means a disease.

This condition is often caused by direct pressure from a herniated disc or degenerative changes in the lumbar spine that cause irritation and inflammation of the nerve roots.

Pain and numbness is felt in  the area of skin supplied the by sensory fibers of the nerve root. In addition the muscles supplied can show weakness.

Radiculopathy pertaining to lower limb is commonly referred to as sciatica.

Neoplasm

Neoplasm is an abnormal mass of tissue as a result of neoplasia.

Neoplasia means new growth in Greek. It denotes abnormal proliferation of cells.

The growth of this clone of cells exceeds, and is uncoordinated with, that of the normal tissues around it.

One of the features of the neoplastic growth is that it persists in the same excessive manner even after cessation of the stimuli.

Neoplasms may be benign, pre-malignant or malignant.

The term tumor is synonymous with a neoplasm that has formed a lump.

Not all neoplasms form lumps.

Posterior Longitudinal Ligament

The posterior longitudinal ligament is situated within the vertebral canal, and extends along the posterior surfaces of the bodies of the vertebrae, from the body of the axis, where it is continuous with the membrana tectoria, to the sacrum.

It is broader above than below, and thicker in the thoracic than in the cervical and lumbar regions.

The ligament is more narrow at the vertebral bodies and wider at the intervertebral disc space. This is significant in understanding certain pathological conditions of the spine such as the typical location for a spinal disc herniation.

At  intervertebral fibrocartilages and contiguous margins of the vertebrae, the ligament is more adherent and  broad.

It is narrow and thick over the centers of the bodies, from which it is separated by the basivertebral veins.

It has an anterior counterpart called anterior longitudinal ligament