The spinal column is made up of spinal bones, called vertebrae, which stack on top of each other. Most vertebrae are separated from the next by intervertebral discs. These intervertebral discs work as shock absorbers. They are made up of a tough fibrous outer layer (annulus fibrosus) and a gelatinous inner core (nucleus pulposus). When the fibrous outer layer of the disc tears (annular tear), the gelatinous inner core can bulge out (herniate); this is a disc herniation.
A herniated disc is also referred to as bulging disc, slipped disc, disc prolapse, torn disc, disc protrusion and ruptured disc. There is not one single correct phrase.
Some disc protrusions are more long standing and associated with bony spurs (osteophytes). This is a type of arthritis of the spine.
The spinal column in the neck region is termed the cervical spine. It is made up of 7 bones (C1 to C7 vertebra) with 8 nerves (C1 – 8) exiting the spinal cord on each side. These nerves supply the back of the head, neck, shoulders and arms.
The spinal column in the chest region is termed the thoracic spine. It has 12 bones (T1-T12). The spinal column in the lower back is termed the lumbar spine and has 5 bones (L1 – 5). The pelvic part of the spine is termed the sacrum and also has 5 bones which are usually fused together (S1 – 5).
The first two cervical vertebra are different from the others. They act as a pivot joint and do not have an intervertebral disc separating them. This allows much more rotation of the head.
Cervical disc herniations can occur at any other level in the neck. Most commonly, they affect the C5/6 and C6/7 discs. C3/4, C4/5 and C7/T1 disc herniations are less common. C2/3 disc herniations are rare.
Disc herniations are often described according to the size and side of the affected disc (e.g. large left C5/6 disc protrusion).
Symptoms of Disc Herniation
Annular tears and disc herniations can cause severe pain. Some disc herniations cause compression of the nearby spinal cord or spinal nerves. Disc herniations in the cervical spine can result in severe pain, numbness, weakness or even paralysis and may require urgent medical attention.
Symptoms typically vary depending on the position of the disc and the size of the herniation.
Symptoms of a disc herniation in the cervical region of the spine (the neck) may include:
- pain in the neck which radiates into the arms;
- pain or numbness in the area of the shoulder blades;
- pins and needles and/or numbness in the arms or hands;
- weakness in the arms or hands;
- unsteadiness or clumsiness.
Causes of Disc Herniation
A disc herniation may be caused by a variety of reasons. Age is one factor. A healthy disc is well hydrated and the outer layer securely encases the inner gel. As discs get older and degenerate they become less hydrated, flatter and the outer layer can become more brittle. This means that it is more likely to let some of the inner gel leak out (herniate). Poor posture, awkward bending or heavy lifting in an awkward position can exert extra pressure on the discs.
Other factors may also increase the risk of developing a prolapsed disc which include a job that involves a lot of lifting or sitting; weight bearing and axial loading occupations, sports and other recreational activities; lack of exercise; obesity, smoking or genetic factors.
MRI (magnetic resonance imaging) typically produces detailed images of bones (vertebrae), discs (intervertebral discs) and nerves in the cervical region and allows for exact diagnosis. Sometimes additional diagnostic investigation is required such as SPECT-CT bone scan, EOS scan, flexion/extension X-ray or nerve conduction studies and electromyography (electrical studies). Occasionally, CT-guided nerve injections can be used for both diagnosis and treatment.
Conservative (non-operative) treatment options will often be considered initially and will aim to reduce pain and associated symptoms and can include:
- medication including simple over-the-counter painkillers or prescribed medication such as mild opiates, short course low-dose muscle relaxants or nerve-type analgesia e.g. pregabalin, amitriptyline;
- manual therapy and massage;
- exercise, including physiotherapy with core strengthening;
- posture optimisation;
- weight optimisation;
- reducing exacerbating factors e.g. ensuring workplace is ergonomic and reducing heavy lifting, twisting or straining;
- CT-guided injections, usually a combination of local anaesthetic and steroid.
If symptoms do not improve with conservative treatment or are severe, e.g. significant weakness or numbness, then surgery should be considered.
The most common operations for cervical disc herniations are foraminotomy (with or without microdiscectomy) and anterior cervical discectomy.
Sydney Disc Herniation Surgery
Dr Laban is a Sydney neurosurgeon and spine surgeon who sees patients with all types of neck and back pain related problems and conditions. If your neck pain and related symptoms are getting in the way of life and not resolving themselves then it is important to get an expert opinion. Contact us to book an appointment with Dr Laban and get the diagnosis and help you need.