By Carrie McCulloch
Carrie McCulloch is a 4th-year medical student at the Mount Sinai School of Medicine, Co-Director of Kinected, and Co-Director of the Functional Anatomy for Movement & Injuries (FAMI) Workshop.
Degenerated discs, prolapsed discs, bulging discs, herniated discs—these terms float around Pilates studios quite freely. Indeed, these conditions are some of the most common reasons why clients with back pain seek help from Pilates instructors in the first place. Despite their familiarity, however, these terms—and the medical jargon surrounding them—can get quite confusing. Here’s a look at the particulars of three common disc problems.
Before delving into what goes wrong with discs, it’s best to start with a general anatomical review of what they are and do, when functioning properly.
The Intervertebral Disc
Commonly likened to a jelly doughnut, an intervertebral (IV) disc has two layers: an inner gelatinous mass (the nucleus pulposus), and an outer fibrous casing (the annulus fibrosus). The content of the nucleus pulposus is mostly water, affording it the ability to act as a modified hydraulic shock absorber every time the spine moves. The water composition, however, decreases with age, and contributes to the progressive decrease of one’s height over time. The tougher annulus fibrosus surrounds the inner pulposus with fibrocartilagenous concentric layers, increasing the disc’s shock absorption capability. In addition to shock absorption, the two components of the IV disc work together to provide intervertebral stability and an axis of rotation for spinal movement.
So what happens when our discs go south? What causes the problem, exactly, and what causes the pain? Here’s a look at three common disc injury scenarios:
DEGENERATIVE DISC DISEASE
What is it?
As mentioned above, as bodies age, so do their intervertebral discs: the nucleus pulposus dries out and loses its shock-absorbing abilities, while the annulus fibrosus becomes brittle and subject to tears. Whether we like it or not, these changes seem to be part of the spine’s normal aging process. In many people, this process goes unnoticed; in others, it causes back pain, the condition known as Degenerative Disc Disease (DDD) and a host of other consequences.
According to the working theory of DDD, which is based on studies of the lumbar spine, the aging process can provoke a degenerative cascade of events. Put as simply as possible, as a disc begins to tear and dysfunction, instability and inflammation ensue, and the spine attempts to compensate by producing more bone in the form of spurs (also called osteophytes). These changes occur on a continuum and can lead to other problems such as arthritis, disc herniations and spinal stenosis.
What causes the pain?
Some controversy surrounds the exact cause of pain in DDD. Current theories point to the interplay of the following factors: the disc’s own nerve supply, inflammation and microinstability. Part of the annulus fibrosus has many nerves running through it, and small tears, or inflammation caused by irritants within the nucleus pulposus, can be painful. This type of pain is known as discogenic as it arises from the disc itself. In addition, as a disc deteriorates and contributes to microinstability, nearby muscles may pick up the slack and provoke painful spasms.
The pain from DDD is usually localized to the site of injury, most commonly in the lumbar or cervical spines, and can be referred to other places in the body, such as the buttocks and posterior thighs. DDD pain, however, is often inseparable from other co-existing degenerative problems, such as disc herniations, that add their own assortment of aches and pains to the body.
DISC BULGE & DISC HERNIATION
What are they?
In addition to degenerating, discs are also infamous for bulging, herniating, protruding, prolapsing and a litany of other terms. Confused by the nomenclature? You’re not alone. A few years ago, it took an entire multidisciplinary task force of spine specialists to come up with recommendations for a universal vocabulary. Here’s a slimmed-down synopsis of their semantics:
Basically, there are two general scenarios that happen when a disc (or some part of it) is displaced from its intervertebral home. First, a disc bulge refers to a generalized outpouching of a disc’s outer edges—i.e., the whole disc appears swollen—that may result from a variety of reasons, both normal and abnormal. In contrast, a disc herniation is defined as a localized displacement—i.e., a focal protrusion—of disc material. In most cases, the disc’s nucleus pulposus is the protruding culprit; it peeps through a tear in the annulus fibrosus and often herniates into the vertebral canal where the spinal cord and nerves reside.
The rest of the terms, then, are regarded as either colloquial synonyms for a disc herniation (e.g. slipped, ruptured and prolapsed) or further classifications of its appearance. For example, a herniation can be called contained (if housed within the outer edges of the annulus fibrosus) or uncontained (if extended beyond the annulus fibrosus). It can also be categorized as protruded, extruded or sequestrated depending on its shape and location. [For images associated with the above terms, click here.]
Both disc herniations and bulges are commonly found in the lumbar and cervical spines and can either be symptomatic or silent.
What causes the pain?
Like DDD, symptomatic disc bulges and herniations can cause localized pain. The purported mechanisms are fairly similar as well: The disc and surrounding ligaments “hurt” from tearing or increased pressure, and if the contents within the nucleus pulposus escape to irritate nearby tissues, inflammation and painful localized muscle spasms can arise. Here’s the difference: If a herniated disc impinges or irritates a nearby spinal nerve root (called a radicle), an affected individual can develop the pain of a radiculopathy. Unlike the deep, aching mechanical pain of back spasms, radicular pain is often described as burning, sharp-shooting and electrical. It also often travels into the extremities, appearing in a particular pattern determined by a nerve’s dermatome (the circumscribed area of skin it supplies). This is why an individual with an impinged L5 spinal nerve root may experience radicular pain along the lateral aspect of the calf. In addition to pain, an impinged nerve may also cause patterns of weakness, numbness and paresthesias (abnormal sensations such as “pins-and-needles”).
Helping clients with disc problems
With its vitalization of core stabilizers and focus on postural awareness, the Pilates method may help clients with a history of disc problems continue their recovery by building and maintaining strong and healthy spines. It’s important to note, however, that working with this client population is not always as black-and-white as learning the anatomy and pathophysiology behind the damaged discs. To be sure, every client’s experience with an injury will differ, as will her response to movement. While guidelines can be helpful (and a few are highlighted below), instructors interested in working with this clientele base should obtain thorough training in anatomy, injuries, and special populations programming.
A few notes to keep in mind:
• Clients with back pain should first seek medical attention and clearance before beginning any exercise regimen. If a green light is given, communicate with the client’s physician and physical therapist to help get everyone on the same page. It may take extra legwork, but creating a dialogue between health care providers is a helpful way to maintain a safe and effective exercise regimen for your client.
• Movement indications and contraindications may differ depending upon the stage of the client’s recovery, the client’s response to movement, and the type, location, and confounding factors of the client’s injury. For example, whereas one individual may initially prefer extension, another may favor flexion. These factors—as well as the functional level of your client—play an important role in determining appropriate exercises and their progression. As a general rule: extreme ranges of motion, exercises that combine flexion and rotation or exert a downward, twisting pressure on the spine, as well as any movement which provokes pain or symptom exacerbation, should be avoided.
Please note: The information contained within this article is intended solely for the education of the reader. It is not to be used as a substitute for medical diagnosis, advice or treatment.
The article was edited from its original version on 1/21/09.
Response: Hard disk recovery programsSo many people do this: In place of a disk recovery utility they run a restore disk to try and recover their data. Nothing could be worse. It erases your files. If you don't know what you're doing call for help. You'll be guided to which software you need.