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Hydroxyapatite

spine-health — Fri, 04 Jan 2008 07:52:57 -0800

Definition

Hydroxyapatite is a calcium phosphate mineral contained in normal bone. The lattice-like structure of hydroxyapatite crystals accounts for the rigidity of bones. Hydroxyapatite is often used in the manufacture of bone void filler products that provide scaffolding for bone growth to supplement a patient’s own bone in orthopedic procedures.

If hydroxyapatite crystals become embedded in or around joints, it may result in a painful inflammatory condition known as hydroxyapatite crystal disease.

Herniated Disc

spine-health — Fri, 04 Jan 2008 07:52:56 -0800

Definition

A herniated disc is a condition in which the annulus fibrosus (outer portion) of the vertebral disc is torn, enabling the nucleus (inner portion) to herniate or extrude through the fibers. The herniated material can compress the nerves around the disc and create pain that can radiate through the back and sometimes down the arms (if the herniation is in the cervical spine) and legs (if the herniation is in the lumbar spine).

Harrington Rod

spine-health — Fri, 04 Jan 2008 07:52:56 -0800

Definition

Harrington rod is a surgical implant used to stretch the spine in order to correct abnormal curvature. The rod is attached to the spine with hooks inserted into the vertebra at the top of the curve and the vertebra at the bottom of the curve.

The Harrington rod has a ratcheting mechanism that works to straighten the spinal curve and stabilize the spine. The vertebrae in between the hooks are then allowed to fuse.

Halo

spine-health — Fri, 04 Jan 2008 07:52:55 -0800

Definition

Halo is a medical device used to stabilize the cervical spine after traumatic injuries to the neck, or after spine surgery. The apparatus consists of a halo vest, stabilization bars and a metal ring encircling the patient’s head and fixated to the skull with multiple pins. The metal pins push up to the skull and not into it. The are placed opposite one another giving counter force and resulting in very firm fixation to the skull. The pin sites require daily cleaning to keep from becoming superficially infected.