Neurological Disorders: Bulging Disc

A Bulging Disc also called as disc bulge is nothing but a bulge or protrusion formed on the surface of the disc material due to slight displacement of the inner contents within the intervertebral disc.

An intervertebral disc is a semisolid material that occupies the space between the two neighbor vertebrae. This soft material is enclosed within a fibrous sheath called as annulus fibrosus. If the soft inner contents come out of the fibrous covering it is called as disc herniation, however if the soft contents just protrude out but still confined to the annulus fibrosus then it is called as a disc bulge.

These bulges commonly occur in the lower back area although they can occur anywhere in the spine.

Size of disc bulge varies from small to large. The disc bulge may be focal or more diffused.

Some authorities consider a disc bulge is an early stage of disc herniation, but a disc bulge need not progress to a full blown herniated disc always.

The causes of disc bulge although not precisely known however thought to be similar to disc herniation. Aging, degeneration of the disc, injuries etc predispose to this condition. The fibrous annulus sheath becomes more elastic & lets the soft disc material to bulge through it. There is no tear or opening in the annulus sheath so the disc material stays inside of it.

Many of these disc bulges do not produce any symptoms and they are seen just incidentally on an MRI of the spine.

The can produce back or neck pain. If the disc bulge is big enough to put pressure effect on the spinal nerve roots then it can result in pinched nerve (pinched spinal nerve root) which can produce pain radiating from the back or neck to the legs or arms. It is called as radiculopathy. There could be muscle weakness, loss of DTR (deep tendon reflexes) and sensory symptoms & signs in the area supplied by the spinal nerve roots.

MRI of the spine is the investigation of choice. It can differentiae a disc herniation from a disc bulge.

An EMG test may help in ruling in or rule out radiculopathy.

Disc bulges are mostly treated non-surgically. Conservative measures including pain medications, physical therapy etc are the mainstay of treatment.

A neurologist is frequently involved in the care of patients with Bulging Disc.