If you’ve recently discovered that you’d need a spinal fusion to cure your back problems or just want to gain insights on this advanced spinal surgery, this article will help you understand all vital factors of spine fusion.

What is Spinal Fusion Surgery?
Simply put, spinal fusion surgery is needed for patients who need the spine to be fused. Due to some reason which we will discuss further on, spine has become unstable, vertebrae slip over one another (spondylolisthesis) and needs screws, plates and bone to become stable again.

Spine looks like a stack of bony blocks kept on one another (Figure 1). The stack is held together by muscles, ligaments, disc, bony architecture, spine curvature among other things. Any damage to any one of these factors can lead to cascading of the stack or slipping of vertebrae on one another called spondylolisthesis.

Factors such as large disc herniation, trauma, accidents, excessive wear and tear with age, congenital or systemic disorders may cause spine to loose its stability. These severe spinal disorders typically cause symptoms of predominant axial back pain which can only be rectified by spinal fusion surgeries. This surgery has greatly evolved over the years and can now be performed through minimally invasive surgery (MIS) techniques as well.

What happens in spondylolisthesis?
Spondylolisthesis (In Greek, spondylo means spine, and listhesis means slipping, sliding)is slippage of one vertebra over the other. Either due to congenital reason or degenerative process (age related wear and tear), a strong piece of bone called pars interarticularis breaks and the locking mechanism which holds the spine together is lost. The spine becomes unstable. When you normally bend forward or backward, there is physiological limitation to this movement which avoids abnormal or excessive damage to normal structures. In Listhesis, this normal limitation of movement is lost and there may be excessive abnormal movement. That is why, your doctor may ask for an Xray in lateral view in flexion and extension (Xray from side view while bending forward and backward).
The muscles and ligaments hold the bones together to a certain extent. Patietnt may have mild discomfort in back. These muscles start giving way and at one point, full tension by muscles and ligaments is inadequate to hold the bones in position. That is when patients starts getting unbearable symptoms. If the slippage is significant enough to cause nerve or dural tube compression, associated symptoms like sciatica, claudication, tingling numbness also start. In severe cases, urine or bowel control is lost.

What are the symptoms of spondylolisthesis?
Many patients with SL may be asymptomatic for many years before developing symptoms. They may have occasional low back pain. Symptomatic patients usually complain of persistent low back pain which increases with activity. The pain may also be present along the muscles of the back and they feel strain in the back due to spasm. They may also get hamstring pull and may walk with slightly bent knee. Change in posture typically worsens their symptoms. Patient mayhave maximum problem while sitting up from sleeping position or standing up from sitting position, or turning in bed may be painful. As discussed earlier, other symptoms like claudication, sciatica, tingling, numbness, urinary or bowel symptoms may develop depending on severity of disease.

What are investigations needed in spondylolisthesis?
Clinical examination is mainstay of diagnosing this condition. The doctor will elicit many signs which may guide him towards diagnosing spondylolisthesis. Important ones are Straight Leg Raising test (SLR), point tenderness over the back, heel walking, toe walking. He will also check the deep tendon reflexes with a hammer and sensory examination as well.
Xray is very important to confirm listhesis. Xray and CT scan show bony structures well whereas Sonography and MRI show soft tissue structures better. So, doctor may ask for an Xray in flexion and extension or oblique views in doubtful conditions. CT scan is most accurate and may be done prior to surgery. Doctor will see 2 main things on Xray/Ct scan – the bony discontinuity at pars and severity of listhesis. There is a grading of spondylolisthesis depending on percentage of slippage.

MRI shows status of nerve compression, disc herniation, soft tissues edema etc. Doctor may order additional tests like bone densitometry to rule out osteoporosis or any other systemic disorder.
What are treatment options for spondylolisthesis?
The mainstay of treatment for spondylolisthesis is conservative treatment. Conservative treatment includes:

  • Pain management- Doctor may prescribe medications to reduce pain, relieve muscle spasm. It has a drawback that muscle spasm in listhesis may be protective and its relief may aggravate the problem. Hot fomentation, bed rest, changing posture may help some patients. Rigorous massage is not recommended as it may further push the bone and increase the severity.
  • Physical therapy – mainstay of physical therapy is relief of spasm and increasing the muscle strength. If baseline strength is more, we may delay the surgery significantly or even avoid it altogether.
  • Bracing – Lumbar bracing using rigid belt is very important as it may reduce abnormal movement of spine and reduce the progression of slippage. It must be used at all waking hours but continuous use may lead to muscle atrophy in the long run.
  • Epidural injections – For patient with severe smptoms who are not yet ready for surgery, injections may be a good option. It will give a relief from symptoms for 3-6 months.

When Is Spinal Fusion Recommended?
Spine fusion is only recommended after all conservative treatments, such as rest, physical therapy, and pain management medication, bracing and belt have fail to improve the spinal condition. As the condition aggravates over time, the doctor will check for conditions and disorders such as:

  • Severe stiffness and pain in the lower back region
  • limited range of back motion due to muscle spasm
  • Failure to maintain normal posture
  • Muscle spasms and tightened hamstrings
  • Weakness and imbalance in legs while tiptoeing or heel walking
  • Sudden limping episodes while walking
And a spinal surgery will only be recommended if one or a combination of the above symptoms develop in the patient for several days despite other non-surgical treatments.

Which Disorders Are Treated By Spinal Fusion?
A spondylolisthesis may benignly develop slowly over several years or due to sudden traumatic injuries. However, several spinal disorders can be treated via a spinal fusion surgery, such as:
  • Large lumbar discs herniations
  • Degenerative disc diseases
  • Spinal stenosis (narrowing of the spinal column)
  • Spondylolisthesis
  • Vertebral fractures
  • Pars-fracture
  • Scoliosis
  • Spinal tumours
How is Spinal Fusion Performed?
The goal of this surgery is to release the compression exerted on the spinal nerves and re-establishing appropriate spinal shape and overall stability. Spine fusion surgery can now be performed in the following ways:

Open Spinal Fusion:
  • When the damage is due to trauma with mutiple pathologies, tumor, redo surgery, etc; open spine surgery helps achieve that goal through a single long incision.
  • In this surgery, as described in the picture above, the surgeon removes the damaged disc between two vertebrae and then fuses those two adjacent vertebrae by using bone grafts and titanium implants such as screws and rods. The incision is closed with surgical sutures, staples and bandages.
  • This surgery takes a while to perform and slightly longer to heal completely.
MIS Lumbar Fusion/ MIS-TLIF
  • Also known as transforaminal lumbar interbody fusion (MIS-TLIF), here, the surgeon repairs the damaged spinal area from the sides of the spine through small incisions (1-2 cms), preventing the permanent and avoidable damage to the muscles and bones by open surgical approach.
  • The patient is positioned facing down, and retractors are inserted from both sides through which the surgeon removes the damaged parts with MIS instruments and an endoscope or microscope.
  • Finally, the bone grafts with cage is inserted into disc space and supported by metal fixations using pedicle screws and rods. The small incisions are closed with relatively fewer sutures and heal much faster as compared to the open surgical incision.
  • Patient is mobilised immediately next day and can continue daily walking and other activities like climbing up and down the stairs, sitting on a chair, etc.
  • Extreme bending, squatting position is avoided for 6-8 weeks.
A typical before and after surgery Xray of lumbar spine with spondylolisthesis If you’re specifically looking for an endoscopic spine surgeon in Mumbai who can guide you with your back pain problems and recommend the most suitable treatment, then you must visit the PowerSpine Clinic in Mumbai. You can also visit the other sections in this PowerSpine Clinic website to learn more about spine and other back pain treatment in Mumbai.


Vertebroplasty/ kyphoplasty is considered to be an advanced MIS treatment whose outcome majorly depends on the experience of the surgeon and the accuracy of the technologies used. And if you’re looking for such a spine surgeon in Mumbai, then Dr. Sumeet Pawar’s PowerSpine Clinic is the only place you’ll need to visit. Dr. Pawar treats all back and spine related problems with the most advanced techniques and devices to ensure highly effective outcomes. You can visit the PowerSpine Clinic at Lilavati Hospital, Bandra; Bhatia Hospital, Tardeo or Savla Hospital, Chembur to learn more about his treatments and consult him to get the best back pain treatment in Mumbai

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