‘We require awareness on spine surgery and spine instrumentation’

Dr Hillol Kanti Pal is the first spine surgeon in north India to perform a two-level lumbar disc replacement (spine arthroplasty) on a 38-year old woman. An AIIMS alumnus, Dr Hilol is presently working at Dr Ram Manohar Lohia (RML) Hospital, New Delhi . His areas of expertise include spine instrumentation, basic neurosciences, neurotrauma, skull base surgery and medical videofilms. Dr Hilol was the first surgeon in India to conduct extra cranial-intra cranial by pass surgery. A quest for challenge made him foray into spine arthroplasty. Dr Pal spoke to Sapna Dogra about the procedure and other aspects related to spine surgery.

What is spine arthroplasty?

Spine arthroplasty provides restoration of the original structure and in course, restoration of pain-free natural mobility of the spine. It is an artificial disc replacement surgery for replacing the damaged spinal disc using an artificial lumbar disc. In this case, we used FDA-approved SB Charite artificial lumbar disc. In December 2004 the US FDA approved this technique.

This surgery is specially done in those cases wherein the backache/neck pain arises due to degeneration of disc. This particular pain responds best to rest. For instance, the patient would not feel any pain in the morning, but as the day progresses the pain becomes unbearable, incapacitating the patient. The pain is so severe that the patient has to lie down to get relief. It affects young patients in their 30s and 40s. This particular implant has been approved by the FDA for patients up to 60 years of age.

Tell us about the patient on whom you did this procedure for the first time.

The patient had been suffering from severe pain for about two years due to degenerative disease of lumber spine. The pain was so severe that she couldn’t stand. She underwent routine radiological investigations including plain radiographs, MRI and CT imaging of her Lumbosacral spine. These investigations confirmed significant degenerative changes at multiple levels. These changes were most marked at L4-L5 and L5-S1 levels. There was a large central disc herniation at L4-L5 and the disc at L5-S1 was largely replaced by air making it dysfunctional.

In our experience, an isolated disc removal at L4-L5 level does not help providing complete relief to this group of patients as almost one-third of them complain of backache subsequently and are termed “Failed Back”. Luckily for her, the FDA had approved the SB Charite Artificial Disc for the lumbosacral spine six months back and it was available. The neurosurgical team at RML offered to do a total replacement of the discs at these two levels. The L4-L5 disc was removed first and a size 3 implant was used. The L5-S1 disc was then removed and surprisingly it accepted only a size 2 implant. This surgery using Charite disc has been performed in six cases in South India in the last six months; but all of these cases have been single level disc replacements.

Who needs this replacement?

This type of surgery is meant for problems where disc has become dysfunctional due to loss of disc height and presence of mediators of pain in the area of disc. The MRI of such cases will show a black disc. Till recently, there was tremendous confusion whether this should be treated or not. Even in latest journals, there are only five-six citations of spine arthroplasty cases. This is a very specific surgery done only in specific cases. I did my first case in April this year and after that have done three more cases.

Is it a simple procedure or a complex one?

It is a complicated surgery as we operate from the front; we open the abdomen whereas most procedures for the back pain are done from the back. Therefore, here certain amount of risk is involved as one has to move major blood vessels like aorta.

One has to have an experience of doing 100-150 spine surgeries to venture into this area. And that’s the reason why very few people venture into this area.

What are the advantages of this surgery? What is the cost of the procedure?

Majority of patients with disc degeneration are conventionally treated by medication and physical therapy. However, a few of them would require surgery. In conventional surgery, the diseased disc is removed through microsurgery. The disc space is allowed to fuse spontaneously.

However, this fusion can lead to potential problems in the future, like accelerated degeneration in discs at the adjacent levels. Artificial disc replacement had been introduced as a solution to this problem.

The major advantage of arthroplasty is that the patient can be mobilised after 24 hours of the surgery. Arthroplasty allows the patient to have normal movement of that particular vertebral body where implant has been put. It has now been shown that it retards the accelerated degeneration that occurs in the posterior elements. This procedure allows almost normal preservation of all spine movements at the operated levels and restores the lordotic curvature of the lumbosacral spine. The option of fusion at a later date, if required, exists.

The surgery is reasonably cheap. One has to pay only for the cost of implant, which is Rs 65,000. The surgery is free.

What do you foresee in spine instrumentation?

In the future, we will have better designs. And it is possible that we would not use metal after some years because of a theoretical risk. Say 40 years down the line, when the bones become brittle but the metal retains it metallic strength, we are afraid that the metal might jet out like rods out of some of old buildings.

Research is being conducted to find such a substance for the implant which will crumble after 10-15 years, so that there is no rod jetting out. As this surgery is only one-year-old, we don’t know what will happen in the future. But I am sure the designs will certainly evolve. I am also going to work on nano-technology and spine fusions. The scenario in India is different. Indians have small and narrow bones and patients come to a doctor very late. Therefore, we need different implants for correction. The companies are also working on to make implants specific to Indian bodies.

What is the state of spine surgery in India?

Spine surgery is at its crossroads as it is neither part of orthopaedics nor neurosurgery. It is unfortunate that hospitals do not have time to perform spine surgeries. There are only 75 spine surgeons doing certain number of cases in the country on a regular basis. I have taken it upon myself to train as many people as I can through CMEs, conferences etc. I want to spread awareness about spine surgery in general and spine instrumentation in particular.

sapna.dogra@expressindia.com