Making Spine Surgery 99% Safe

How safe is spine surgery today? In the hands of a well-equipped team, very safe: Dr. SK Rajan, Chief - Neuro Spine Surgery & Additional Director - Neurosurgery, Artemis Hospitals, Gurugram, India, says spine surgery has reached almost 99% safety over the past few decades. He credits three things working together: technology, teamwork and training specific to high-end spine surgery.

That figure is not a promise that every operation is risk-free. It is the result of a system built to close off each point at which spine surgery can go wrong, from the first consultation to the final screw. This guide sets out where complications come from, how a team is organised to prevent them, and which technologies make the difference in theatre.

Spine surgery safety starts with the right patient

Most people with back pain never need an operation. Almost everyone experiences back pain at some point in life, and Dr. Rajan's point of departure is that in the majority of patients it settles with medicines within six to eight weeks, because it is mostly muscular. Medicines, physiotherapy and exercise resolve most of the rest.

Surgery is reserved for a defined subset of patients: those with nerve or spinal cord compression from cervical spondylosis (age-related wear of the neck spine), tumours, infections such as spinal tuberculosis, and spinal deformity, fractures that do not settle with medical treatment, and spinal stenosis (narrowing of the spinal canal) that damages quality of life. The detail of each indication, and how a referring doctor can recognise it, is covered in the guide to when spine surgery is needed, with stay and cost.

The safety argument begins here because an operation that should never have been done cannot be made safe by any amount of technology. Selecting the right patient is the first safety measure, not an administrative step before the real work.

Spine surgery risks: what can go wrong

Every surgery carries risk, and the spine is no exception. Dr. Rajan lists the complications that a spine team works to prevent:

• Infection, from a superficial wound infection to deeper infection around implants.
• Nerve injury, to a nerve root or to the spinal cord itself.
• Bleeding.
• Dural tear, a tear in the dura, the tough membrane that encloses the spinal cord and nerve roots and holds the cerebrospinal fluid.
• Problems with bone cement or screws, where implants or cement end up where they should not be.

He illustrated the last category with images from operations done wrongly: in one, a screw had been driven into the spinal canal; in another, bone cement had leaked into the canal and was compressing the spinal cord. Both are technical errors of placement, and both are precisely the errors that modern intraoperative imaging is designed to catch.

In many places around the world, he notes, spine surgery is still very risky. The gap between that reality and a safety rate near 99% is the subject of the rest of this guide.

Why spine surgery complications happen: three points of failure

Dr. Rajan places the causes of complications at three levels: errors in the diagnosis, errors in selecting the right doctor for the surgery, and errors in the surgery itself. Each needs a different safeguard.

Errors of diagnosis

This is the level he singles out for referring doctors. Patients sometimes travel a long distance for spine surgery without a major reason to operate. His rules are direct:

1. If the cause of the pain or weakness cannot be found, it is not a case for surgery.
2. Simple back pain or simple leg pain is often not a good indication for surgery.
3. A bad-looking MRI does not, on its own, mean the patient needs surgery.

The third rule matters because degenerative changes on MRI are common in adults who have no symptoms at all. The decision to operate rests on matching the imaging to the patient's symptoms and examination findings, not on the scan alone.

Errors in choosing the surgeon

The second level is the choice of doctor. Complex spine surgery depends on training specific to high-end spine work, and on a surgeon who does it regularly. Dr. Rajan's own route is an example of what that training involves: a neurosurgeon by training, he completed medical school, a specialisation in surgery and then neurosurgery, followed by a few years of spine surgery training in hospitals in the USA, the UK and Bombay, and worked as a professor in the government sector before joining Artemis Hospitals.

Errors during the operation

The third level is the operation itself: the wrong level, a misplaced screw, a nerve injured during decompression, cement in the wrong place. This is where technology carries most of the weight, as the sections below explain.

Why spine surgery safety needs team, technology and talent

"Excellence", in Dr. Rajan's formulation, cannot be achieved in spine care without a combination of team, technology and talent. No single element is sufficient. A gifted surgeon with poor imaging can still misplace screws; the best equipment in the hands of an inexperienced team will not prevent a wrong diagnosis.

The integrated spine clinic

The team element is organised at Artemis Hospitals as an integrated spine clinic. Specialists who would otherwise see a patient in sequence work together to improve the quality of both diagnosis and treatment. The clinic brings together:

• a rheumatologist, for inflammatory and systemic causes of back pain;
• an orthopaedic surgeon;
• a neurologist, to separate spinal causes of weakness or numbness from neurological disease elsewhere;
• a pain specialist, for patients who can be managed without an operation;
• the spine neurosurgeon.

The model works against the error of diagnosis he describes, which is operating on a patient whose pain has another cause. A patient whose back pain is inflammatory, or whose leg weakness is neurological rather than compressive, is identified before reaching the operating table.

The technology that makes spine surgery safer

Dr. Rajan describes a "circle of safety, accuracy and speedy recovery" built from six elements, each aimed at a specific failure:

• A modern operating microscope, which magnifies and illuminates the nerves and dura during decompression.
• Spine navigation, computer guidance that shows the position of instruments against the patient's own anatomy.
• Keyhole (minimally invasive) spine surgery through a tube system.
• The O-arm, for three-dimensional imaging inside the operating theatre.
• Intraoperative neuromonitoring, which tracks the function of the spinal cord and nerves while the operation is under way.
• A special positioning frame, which allows the patient to be positioned safely for spine surgery.

The O-arm and computerised spine surgery

The O-arm is a mobile imaging system that rotates around the patient on the operating table and produces three-dimensional images of the spine during surgery. Dr. Rajan calls the resulting set-up a digital spine theatre, and the technique computerised spine surgery.

The system acquires real-time data on the individual patient's anatomy and helps the surgeon navigate through the procedure. When screws are being placed, the images give an exact idea of the size of the screw, the size and quality of the bone, and the direction to take. Even before the incision is made, the surgeon can see the spine and bone from above the skin, which, in his words, increases accuracy tremendously. In his account, the O-arm has enabled his neuro spine team to perform minimally invasive keyhole spine surgery with more than 99% safety.

That is the direct answer to the misplaced screw and the leaked cement shown earlier. Both are placement errors, and both become visible on three-dimensional imaging taken in theatre. The masterclass on recent advances in spine surgery, a separate session by Dr. Rajan, compares the O-arm with 3D C-arms and intraoperative CT and explains how navigation is registered to the patient.

Intraoperative neuromonitoring

Intraoperative neuromonitoring records electrical signals travelling through the spinal cord and nerves during the operation, so that the team is warned if a structure is under threat while there is still time to change course. Dr. Rajan confirmed that his team uses it regularly. His presentation concentrated on minimally invasive surgery and navigation for reasons of time, but neuromonitoring is part of the same safety system.

Keyhole surgery as a safety measure

Keyhole surgery is usually presented as a comfort benefit: smaller scars and faster recovery. Dr. Rajan presents it also as a safety measure. Conventional open surgery requires the surgeon to cut through a large amount of back muscle to reach the spine; navigation-guided keyhole surgery reaches the same target without cutting the muscles.

Two technical details from his cases show how far the approach now extends:

• Through small tubes, an endoscope can be passed into the spinal canal. An "over the top" approach from one side allows the surgeon to decompress (relieve the pressure on) the nerve root on the opposite side as well, without a second exposure.
• In patients with osteoporotic bone, cement can now be delivered through specially designed screws to strengthen the bone around them, so that the screws grip securely. Elderly women who are overweight or osteoporotic can then have keyhole surgery rather than open surgery.

In his series, patients with dislocation of several vertebrae have had screws placed by the same keyhole method and were standing and walking the day after surgery. He also showed spinal tumours removed by the keyhole method, and screw fixations done through a small cut where open surgery would normally be needed.

Recovery after safer spine surgery

For the patient, safer surgery means a shorter, more predictable recovery. In the case series Dr. Rajan presented:

• a man whose arm was too weak to lift because of a compressed nerve in the neck had the disc removed and replaced with an implant, went home three days after surgery, and his strength was expected to return to normal after a few weeks of physiotherapy;
• an elderly woman with an osteoporotic spinal fracture, treated by injecting cement through a minimally invasive route, walked the next day;
• patients with lumbar canal stenosis treated through cuts about one inch long walked the next day.

For international patients who arrive walking, with neck and arm pain or back pain running into the legs, he puts the usual hospital stay at three to four days and the time in the country at about two weeks. His cost figures for common operations are set out in the article on when spine surgery is needed.

How to choose a safe spine surgery centre

A safe spine surgery centre guards against all three points of failure, because safety in spine surgery is a property of the whole system, not of one surgeon or one machine. When choosing where to send a patient, referring doctors can ask three questions:

1. Will the diagnosis be checked by more than one specialist?
2. Is the surgeon trained in, and regularly performing, high-end spine surgery?
3. Does the theatre have three-dimensional imaging, navigation and neuromonitoring available together?

The questions from referring doctors, including surgery for children with neural tube defects and the use of neuromonitoring, are collected in the Live Discussion from this masterclass. Further spine specialists and procedures are listed in the neuro spine surgery specialty hub.