Intervertebral discs are located between adjacent vertebrae of the spine.   They consist of an outer layer called the annulus fibrosus, that surrounds the nucleus pulposus.  The annulus fibrosus consists of many concentric rings of fibrous material that contains the gel like nucleus pulposus. The nucleus acts as a shock absorber and allows movement between adjacent vertebrae. The disc can be thought of as a doughnut: the annulus fibrosis is analogous to the dough and the nucleus pulposus the jelly filling.

There are three grades of disc injury

• Grade 1: Annular strain – this is the lowest grade of disc injury and involves a tearing some of the outer fibres of the annulus fibrosus.
• Grade 2: Disc bulge – due to ageing and injury cracks form in the annulus fibrosus that allows the jelly like nucleus pulposus to move through the annulus towards the edge of the disc.  This causes the disc to bulge, impinging onto adjacent structures causing pain.  If the bulge presses onto a nerve root it can cause pain, weakness and altered sensation along the path of the nerve.
• Grade 3 Disc Prolapse (Slipped Disc).  A disc bulge may develop into a prolapsed disc (slipped disc) in which the jelly like nucleus pulposus breaches the annulus fibrosus.  The contents of the nucleus cause a strong inflammatory reaction in the surrounding tissues and therefore may be very painful.  Almost all slipped discs in the lower back occur between L4 and L5 or L5 and S1 i.e. in the lowest two most discs.

Causes of disc injury

• Disc injuries are most common in the 25-45 age group.  As we grow older the jelly like nucleus pulposus dries out making it less likely to bulge or herniate.
• Injuries are more common with a history of heavy manual work – especially if incorrect lifting techniques are employed.
• Trauma – discs may be damaged in an accident are especially vulnerable when lifting with a bent and rotated back.

Symptoms of Slipped Disc

Disc bulges and herniation may press against adjacent structures causing pain.  Overlying muscles may go into spasm.  Nerves branch off the spinal cord and body exit the spine just above each disc. A spinal disc herniation can press against the adjacent nerve causing symptoms along the course of that nerve. A slipped disc can produce varying degrees of pain in the back along with numbness or weakness.

• Numbness, tingling, weakness, or pain in the buttocks, back, legs , or feet
• Pain down the back of each leg from the buttocks to the knee (this is called sciatica)
• Symptoms are worse in the morning for 20-60 minutes and at the end of the day
• Slipped Disc Pain aggravated by
  • Bending forwards
  • Sitting
  • Lifting
  • Coughing or straining on the toilet
• Slipped Disc Pain relieved by
  • Lying down
  • Standing up and moving around
• Less common symptoms – if experienced seek medical attention immediately
  • Numbness and tingling around the anus or genitals
  • Difficulty controlling bowel movements or bladder function

Symptoms typically last 3-6 months.

What you can do

• Ice therapy
• Rest  -  avoidance and reduction of aggravating activities
• Employ correct posture and body use to avoid unnecessary stress on back
• Anti inflammatory medication – speak to your doctor or pharmacist about a suitable product

Slipped Disc Treatment

• Massage to relieve spasm in overlying muscles and therefore decrease pain
• Osteopathic techniques to increase circulation to discs e.g. traction
• Prescribe exercises to alleviate pain and reduce spinal disc herniation
• Reduce mechanical load on affected area by:
  • Improving alignment of spine and pelvis
  • Spinal manipulation and joint stretches to increase movement in adjacent areas of the spine to reduce loading on affected discs
  • Hamstrings stretching to reduce flexion loading on spine
  • Prescription of exercises to improve core stability

Tags: back pain, low back pain