Human spine is made up of series of bone called vertebrae placed one above another, in between these vertebrae intervertebral disc is located. Disc is a cushion like substance acting like a shock absorber in between two vertebrae. It has inner soft jelly like material (nucleus) covered by outer tough rubbery ring (annulus).
Herniation refers to displacement of disk material beyond the normal boundary of the disk space. When the herniated disk bulges out toward the spinal canal, it puts pressure and pinches the spinal nerves, causing pain. A herniated disk occurs anywhere along the spine, but most often occurs in the lower back
It is called by different terms slip disc, bulging disc, herniated disc, protruding disc, ruptured disc etc.
Common facts:
- Lumbar disc prolapse is the common cause of back and leg pain (sciatica and radiculopathy)
- Estimated incidence of herniated disc – 5 to 20 cases per 1000 adults annually
- Life time incidence of 2% for symptomatic disc herniation
- 95% of disc herniation occurs in lower lumbar levels (L4-L5, L5-S1)
- Imaging shows 20% & 35% of working population have asymptomatic disc herniation
- 85% patients with symptoms associated with acute herniated disc will resolve within 8 to 12 weeks
Risk factors:
- Increasing age – Often related to gradual wear and tear process that occur as we grow older (35 – 50 years of age)
- Male have roughly doubled risk of ruptured disc compared with women
- Improper lifting – Improper lifting technique, using back muscle instead of legs and twisting while lifting might results in disc prolapse
- Weight – Excess weight gain adds stress on the disk to support additional weight in the lower back
- Strenuous and repetitive activities that strain your back – Majority of jobs are physically demanding requiring continuous and repeated lifting, pulling, bending, or twisting strains your back leads disc prolapse
- Cigarette smoking – Nicotine used in cigar restricts blood flow to disc there by aggravates degeneration process and delays healing leading to cracks in disc
- Family history
- Genetic and environmental factors
Causes:
Repetitive strenuous mechanical activities
- Sudden violent trauma
- Poor posture – at work and during normal routine daily activities
- Sedentary life style
Symptoms:
- Lumbar disc prolapse can present with varied presentation
- Continuous or intermittent back pain
- Sciatica or Leg pain
- Activity related back pain
- Numbness in lower limbs
- Weakness in lower limbs
- Loss of sensation in leg and foot
- Difficultly in griping the footwear
- Bowel and bladder disturbance (urgency, loss on control, straining- Cauda Equina syndrome –seek immediate medical attention)
- Muscle spasms
- The presence of these symptoms warrants an hospital visit
- Lumbar disc prolapse can diagnosed by MRI
- Not all disc prolapse will require surgery, only few percentage of them depending upon the symptoms and severity of disc prolapse on MRI
Treatment options: is varied based on nature of disc prolapse
- Self-care – Restricting the activity, ice/heat therapy – Too long bed rest may give you fragile and weak muscles, and rigid joints, which will make it difficult to do activities that could help curtail the pain.
- Medication – Nonsteroidal anti-inflammatory medications, Analgesic (painkiller), muscle relaxants
- Local epidural steroid injection if not relived by medications
- Physiotherapy – Strengthening exercises following percutaneous electrical nerve simulation (PENS) and transcutaneous electrical nerve simulation (TENS) to reduce muscle spasm
- No role of traction
- Steroids – No long-term benefits, can have drug related complications
Indications for surgery include
- Non-improvement of symptoms after a period of conservative therapy
- Recurrent episodes of pain
- Weakness of leg with bowel and bladder disturbance
Goal of surgery is to remove a portion of disc, which has come out of its confines and is pressing on the nerve, called discectomy.
Discectomy is performed in a minimal invasive fashion by endoscopy or tubular assisted approach to minimise the damage to surrounding muscles. Surgery is performed under general anaesthesia with a small incision (around 2 cms ) in the back
What can I expect after surgery?
- Patient are made to walk the same day
- Patients who undergo surgery generally do well and experience benefits of early regression of pain and early return to activity.
- Typically leg pain is the first symptom to reduce followed by back pain and weakness in leg
- There’s a 5 % to 10 % chance of recurrent disc herniation after the surgery
Lifestyle modification, strengthening of back muscle, routine exercises reduces the percentage of recurrence.
For details – read section on “Lumbar disc surgery”
