Disc herniation can occur at any spinal level, however, lumber disc herniation is the most common resulting in lower back pain which can include referred symptoms into the leg. A disc herniation occurs when part of the material from the disc is displaced into the intervertebral foramina. The herniation occurs when the outer annulus fibrous becomes compromised and the internal material from the nucleus pulposus gets pushed outwards. This can correlate with loading the lumbar spine through repeated bending over movements or staying in a flexed position for an extended period of time which results in increased compression of the disc.
As mentioned above the disc in made up of an outer annulus fibroses which is a serious of fibrous rings, and a gelatinous core that is the nucleus pulposus. This disc sits in between two vertebral bodies and allows for force dissipation and a cushioning between the two vertebras. The herniation of the disc occurs due to the compressive forces placed on the disc that causes the disc to bulge which may then press on the nerve root at that level. A local inflammatory response may also irritate the nerve root.
There are a variety of reasons that can cause disc herniations. The most common reason is due to age, as we get older out discs degenerate with the annulus fibroses becoming less elastic and the nucleus pulpous dehydrating, leading to the disc being less able to accommodate the compressive forces going through it. The next most common cause is due to an acute injury such, as lifting a heavy item off the floor or combined with a twisting motion such as throwing a bag into a skip etc.
Disc herniation can occur at any level of the spine with the lumber spine being the most common, followed by the cervical spine. 95% of disc herniations in the lumbar spine are between the L4/5 and L5/S1 level and in the neck the most common herniations occur between C5/6 and C6/7.
Disc herniation occur in 5-20 cases per 1000 adults annually and usually in 30 or 50 year olds. It has a 2:1 ration of male to female occurrences. It can also be common to have another herniation following a discectomy surgery.
You should consultant immediate medical treatment if you have any of the following symptoms:
- Sensory or strength loss in both legs
- Saddle anaesthesia – loss of sensation in the groin area
- Recent onset of bladder dysfunction (such as urinary retention or incontinence)
- Recent onset of bowel incontinence
- Recent onset of sexual dysfunction
Physiotherapy can help manage symptoms through education, advice and the prescription of:
- Aerobic and stretching exercises
- Motor control exercises
- Strengthening and Proprioceptive exercises
- Manual therapy and taping
- Cortico steroids can help in reducing inflammation in the area and reduce symptoms.
- Discectomies involve the surgical removal of the disc bulge that is compressing the nerve.