Lumbar Disc Herniation
Spinal discs play a crucial role in the lower back, serving as shock absorbers between the vertebrae, supporting the upper body, and allowing a wide range of movement in all directions. If a disc herniates and leaks some of its inner material, though, the disc can quickly go from easing daily life to aggravating a nerve, triggering back pain and possibly pain and nerve symptoms down the leg.
Lumbar disc herniations most often affect people aged 30 to 55 but can occur at all ages. In physical therapy, patients frequently will present with a history of relaxed sitting spinal alignment, engage in frequent flexion of the lumbar spine, and commonly demonstrate limited ability range of motion when extending the lumbar spine. Only 35% of patients afflicted with lower back pain will experience sciatica as a majority of cases manifest as only local back pain.
Disc herniation symptoms usually start for no apparent reason. At the time of initial consultation with a physician or physical therapist 66% of patients effected with lower back pain are unable to identify the reason for their symptoms. Only one third of patients are able to identify an event that produced their disorder.
This article covers how a lumbar herniated disc develops, how it is diagnosed, and the available surgical and non-surgical treatment options.
How a Lumbar Disc Herniates
A tough outer ring called the annulus protects the gel-like interior of each disc, known as the nucleus pulposus.
Due to aging and general wear and tear, the discs lose some of the fluid that makes them pliable and spongy. As a result, the discs tend to become flatter and harder. This process—known as disc degeneration—starts fairly early in life, often showing up in imaging tests in early adulthood.
When pressure or stress is placed on the spine, the disc’s outer ring may bulge, crack, or tear. If this occurs in the lower back (the lumbar spine), the disc herniation or protrusion may push against the nearby spinal nerve root and can irritate the nerve. The result is shooting pains into the buttock and down the leg referred to as sciatica.
A person with a herniated disc may be told by the doctor that degenerative disc disease led to the lumbar herniated disc. This term can be alarming and misleading. Degenerative disc disease is not a progressive disease per se, and it does not always cause chronic or persistent problems.
Lumbar Herniated Disc Symptoms Are Usually Short-Lived
While a lumbar herniated disc can be extremely painful, for most people the symptoms are not long-lasting. About 48% of patients afflicted with lower back pain will no longer report symptoms after one week of symptom onset. That number improves up to 86% by the end of the first month and soars up to 92% after 8 weeks, even if they have had no medical treatment.
In the management of lumbar disc herniations that have been present for less than one-year, lumbar extension stretching exercises are the standard of care to help move the herniated area away from the spinal nerves. In general, it is thought that the symptoms get better because the smaller size of the herniated material reduces the likelihood it will irritate the nerve root.
Although a lumbar herniated disc usually triggers attention when it becomes painful, medical research has found it is common for people to have a lumbar disc herniation in their lumbar spine, but no associated pain or other symptoms. It is for this reason that care must be taken in the diagnosis to be sure a herniated lumbar disc is causing the problem.
Other Terms for Herniated Disc: Slipped Disc, Ruptured Disc
A herniated disc may be referred to by many names, such as a slipped disc, or a ruptured or bulging disc. The term slipped disc can cause confusion since spinal discs are firmly attached to the vertebrae and do not slip or move—rather, it is just the gel-like inner material of the disc “slips” out of the inside.
Another common term for a herniated disc is a pinched nerve. This term describes the effect the herniated disc material has on a nearby nerve as it compresses or “pinches” that nerve.
A lumbar herniated disc may also be described in reference to its main symptoms, such as sciatica, which is caused by the leaked disc material affecting the large sciatic nerve. When a nerve root in the lower back that runs into the large sciatic nerve is irritated, pain and symptoms may radiate along the path of the sciatic nerve: down the back of the leg and into the foot and toes. Sciatica may also be referred to by its main medical term, radiculopathy.