Spinal discs act as cushions between the vertebrae in your spine. They’re composed of an outer layer of tough cartilage that surrounds softer cartilage in the centre. Spinal discs are the shock-absorbing rings of fibrocartilage that separate our bony vertebral bodies while allowing movement at each spinal level, and enough room for the major spinal nerves to exit from the spinal canal and travel to our limbs. The annulus is the outer section of the spinal disc, consisting of several layers of multi-directional fibrocartilaginous fibres all densely packed to create a wall around the glycoprotein filled jelly-like central disc nucleus. The degree of spinal disc injury varies considerably from mild disc strains or internal derangements, mild-moderate-severe disc bulges through to complete disc rupture and herniation of the nucleus through the annular wall. As discs age, biochemical changes occur, they lose their water content, collapse and start to bulge. Again, this occurs in all human beings over time. As a disc slowly degenerates, the surrounding bone sees more stress and bone reacts to stress by forming more bone, hence the development of bone spurs. This is a normal aging process of the spine. Whereas 100% of us develop bulging discs and bone spurs beyond 60 years, roughly 7-10% of people end up having surgery on the lumbar spine. About 1% of us have surgery on the cervical spine. The most common reason for this is because the nervous system, which runs down the middle of the spine for protection, becomes impinged by either disc material or bone spurs. At the cervical and thoracic levels, the spinal cord could be pinched or the nerve roots that come off the spinal cord in the lumbar region could be pinched.
Disks show signs of wear and tear with age. Over time, disks dehydrate and their cartilage stiffens. These changes can cause the outer layer of the disk to bulge out fairly evenly all the way around its circumference. A bulging disk doesn’t always affect the entire area of a disk. Only the outer layer of tough cartilage is involved. A herniated disk, on the other hand, results when a crack in the tough outer layer of cartilage allows some of the softer inner cartilage to protrude out of the disk. Herniated disks are also called ruptured disks or slipped disks, although the whole disk does not rupture or slip. Only the small area of the crack is affected.
The most common cause for a bulging disk is age. This condition can happen to people in their 20’s, but it is more commonly found in people who are in their 30’s and 40’s. When you get older the cartilage dries out or stiffens and a part of the outer layer of your disk will starts to bulge out. If the bulging disk comes in contact with the spinal nerve, the condition can cause discomfort and pain. The prevalence of disk degeneration in asymptomatic individuals increased from 37% of 20-year-old individuals to 96% of 80-year-old individuals. Disk bulge prevalence increased from 30% of those 20 years of age to 84% of those 80 years of age. Disk protrusion prevalence increased from 29% of those 20 years of age to 43% of those 80 years of age. The prevalence of annular fissure increased from 19% of those 20 years of age to 29% of those 80 years of age. A bulging disc is usually considered a normal part of aging. Some discs most likely begin to bulge as a part of both the aging process and the degeneration process of the intervertebral disc. A bulging disc is not necessarily a sign that anything serious is happening to your spine.
A herniated disc on the other hand, means that the outer layer of the disk gets ruptured or cracked and the inner and softer part gets squeezed out. As previously stated, a herniated disk is likely to cause more pain since it usually extends further out and therefore is more likely to irritate nerve roots. Symptoms of a herniated disk include back pain, numbness or weakness in an arm or a leg. If you feel any back pain or neck pain you should visit a spine specialist. Compared with a bulging disk, a herniated disk is more likely to cause pain because it generally protrudes farther and is more likely to irritate nerve roots. The irritation can be from compression of the nerve or, much more commonly, the herniation causes a painful inflammation of the nerve root.
As with many mechanical problems in our body. If we try and keep ourselves mobile and strong, we can hopefully prevent a lot of injuries. The same applies with discs. Hence, it is important to try and maintain a good posture as much as possible. Avoid slumped postures, slumping will over-stress a disc over time. Perhaps it could cause an injury, or predispose to one if the area is weakened. Practice good lifting technique. Use your legs as much as you can when lifting to avoid the strain coming through the back. Stand straight onto the object you’re lifting, and hold the object close to your body where possible. Don’t overdo it! If it’s too heavy for you, ask for help or wait until someone is around to help you.
Most people with back pain with leg symptoms have a herniated disc on MRI. If an imaging test indicates that you have a herniated disk, that disk might not be the cause of your back pain. Many people have MRI evidence of herniated disks and have no back pain at all. Both scenarios are possible. Hence it is important to be assessed by a spine specialist who deals with such issues as a routine in his/ her practice. Herniated disc with alarming symptoms will need more invasive treatment like surgery as elaborated in our website elsewhere whereas most disc bulges may need only life style modifications and simpler treatment. It is in your best interest to get evaluated by a Spine specialist nearby for best assessment. It is important to be assessed by a spine specialist so that your symptoms can be matched with radiologic findings.