The human spine is a beautiful structure – strong enough to bear our weight, keep us erect and protect our spinal cord, but at the same time flexible enough to let us bend and rotate. This remarkable strength and manoeuvrability is because of the arrangement of the bones, called vertebrae, which make up the spine. 33 spinal bones or vertebrae are arranged one on top of each other. Strong ligaments and muscles surrounding the spine keep the bones in position and therefore, the spine remains erect. These vertebrae surround and protect the spinal nerves that arise from the brain and travel to different parts of the body. Between each of these vertebrae are cushion like structures called discs which act as shock absorbers. When the disc present between 2 vertebrae gets injured due to lifting of heavy weights, trauma or straining, it could bulge outside, compress the spinal cord /nerves and cause a disease known as disc bulge or a disc prolapse. It could also be called slipped disc or disc herniation.
Who gets a disc prolapse?
Disc prolapse can occur for anybody. It is more common in males and its incidence is high between 30 to 50 years of age.
What causes a disc prolapse?
Disc prolapse could be caused by an accident or trauma, lifting unaccustomed heavy weights, travelling in bumpy roads, straining your backs too much. In a good numbers of patients, the correct inciting event may not be picked up at all.
At which level in the spinal cord are disc prolapses common?
Disc prolapses are common in the lumbar (lower back) level because of the curvature of the spine (lordosis). Therefore it is common to see disc prolapses at L4-5 and L5-S1 levels. This prolapse can cause compression of the spinal nerves exiting the spine and cause symptoms like pain, tingling and numbness radiating down the legs. Another common region to have disc prolapse is the cervical (neck) spine which causes pain, tingling and numbness radiating down the hands.
What exactly goes wrong in a disc prolapse?
When the disc actually bulges out, it commonly goes towards the back or posteriorly where the spinal cord and spinal nerves are passing down the spine. This compression causes a mechanical and inflammatory change around the nerves. This results in symptoms like pain, tingling and numbness radiating down the course of the nerve. In case of a lumbar disc prolapse, patients have radiating pain down the legs (Sciatica)
What are the symptoms of disc prolapse?
Mild compression causes symptoms like back pain radiating down the legs, tingling, numbness, ‘electric shock’ like sensations, pins and needles, etc. These symptoms may be there in the lower backs, buttocks, back / side of the thighs, back of the knees, calf muscles, and ankles and all the way down to the soles and toes. These symptoms can occur in any one side or on both. Depending on the level and degree of compression, the symptoms may vary. On visiting a physician, he may check sensations, motor power and reflexes along the different suspected nerves. Straight leg raising test can clinically suggest nerve root compression.
What happens in case of a severe compression?
Severe disc prolapse and compression of the spinal nerves results in inability to move the ankle or foot, inability to control bowel habits and urination or total numbness of the entire limb. Severe compression could also lead to numbness around the saddle region (around the anus) called cauda equine syndrome. This could be because of a trauma or a major fall requires urgent surgical decompression. Other red flags of back pain include back pain with high fever suggestive of an infection, tumour, major trauma, vertebral fracture, etc. If you have any of these symptoms, see your physician immediately.
Does disc prolapse always require treatment?
Luckily in about 70 to 80% of patients, the disc prolapse resolves on its own. So even though patients have sciatica pain due to disc prolapse, unless it is a severe disc prolapse, conservative management is sufficient for the first 6 weeks. So most disc prolapses can be treated conservatively with pain killers for the first 6 weeks.
How is it possible to confirm the diagnosis of disc prolapse?
Your physician may ask you to take x rays and MRI of the lumbar spine. X rays may show reduction in disc height and MRI may confirm presence of disc bulge / disc prolapse / disc herniation. Nerve conduction studies and EMG may supplement these findings. Keeping these records safely is essential for medical records and insurance purposes.
How is disc prolapse treated conservatively?
Conservative management is required in the first 6 weeks or if your physician feels the disc prolapse is mild in nature.
- Medicines: Simple analgesics or anti-inflammatory medications may be prescribed.
- Nerve related medications: Nerve pain responds to certain medicines better than it does to regular painkillers.
- In some situations, nerve medicines, muscle relaxants and oral steroids are used.
- Avoid lifting heavy weights, avoid smoking.
- Physical therapy is essential to resume normal activities. Modalities like TENS, ultrasonic waves, interferential therapy, are beneficial and work well in mild disease. Spinal flossing and core strengthening exercises will hasten recovery. Yoga is beneficial.
- Bed rest for more than 3 days is not advisable. Patients should be encouraged to resume mild activity and physical therapy and rehabilitation exercises with medications as soon as possible.
- Wearing lumbar belt / supports continuously or for long periods of time can cause muscle atrophy and is not advisable unless specifically indicated. Spinal traction has conflicting evidence in terms of usage in disc prolapse patients.
How to treat disc prolapse?
If in spite of conservative management, back pain and radiating leg pain still persists, patients could consider nerve root / epidural injections in pain clinics. Pain physicians offer interventional procedures for pain like
- Nerve root injections: Nerve root injections are done with x ray guidance around the nerve which is suspected to be compressed. Medications like local anesthetics and steroids may be used in these procedures. The anti-inflammatory medication reduces nerve root inflammation and edema caused by compression and relieves pain.
- Epidural injections: Caudal and lumbar epidural injections are effective in relieving sciatic pain. Supplementary physical therapy exercises will prolong the effects of therapeutic injections. If required, these procedures can be repeated.
- Disc decompression procedures: Disc decompression procedures like decompressors, hydro dissections, nucleotomes are pain procedures meant to reduce the disc material and thereby relieve pain. Percutaneous discectomies are day care procedures done under local anesthesia and are safe because they are done by injections through the skin and can not cause any permanent damage.
- Endoscopic Discectomy: Endoscopic Discectomy is a keyhole minimally invasive targeted spine procedure. This procedure is done under sedation and is meant to remove the protruded disc material through keyhole.
What are the surgical options available for disc prolapse?
Open surgery under general anesthesia is reserved for patients with neurological deficits like foot drop, complete numbness of the legs, inability to control bladder and bowel habits, severe pain not responding to conservative management or nerve root blocks. Cauda equine syndrome requires urgent surgical decompression.
Surgical options available include laminectomies, discectomies, micro discectomies, endoscopic discectomies, lumbar stabilizations, lumbar interbody fusion surgeries (TLIF), disc replacements, etc.
These procedures require a hospital stay of 3-5 days and recovery time of 2-3 weeks. Post-operative physical therapy / spine strengthening is always advised. Complications include infection, bleeding, paraplegia, recurrence of pain, etc.