MEDICAL MATTERS Dr Muiris HoustonIt is not often you get to read about original breakthroughs in medicine. Yet this is precisely what awaits readers of a recently published biography of Malachy Smyth, a Monoghan-born orthopaedic surgeon.
To abolish pain is one of the most satisfying achievements of a physician's life. Dr Smyth went one step further: he carried out a definitive experiment showing that sciatic back pain was due to a problem with the intervertebral disc. He demonstrated, beyond doubt, the cause of back pain in his patients and how it could be eradicated.
Now retired in Co Monaghan, after a varied life that took him from Britain to the US, via military service in the RAF in North Africa, Dr Smyth has told his fascinating life story to author Aubrey Malone.
As a young orthopaedic surgeon in training, Malachy Smyth began a series of experiments on patients with back pain.
He chose those between 20 and 25 years of age, all with first-time symptoms of a herniated intervertebral disc.
He removed the patient's diseased disc in every case. But rather than sew up the patient, the now missing disc was replaced by a nylon loop which passed under the nerve at the same site the disc had pressed on.
Both ends of the loop were brought to the outside through the skin incision. The nylon was wound round the first sacral root, a large nerve supplying many of the leg muscles.
The patient woke up, pain free, in his bed. Two days later, the experiment started and is vividly described.
"The two ends of nylon stuck through the wound like two antennae. Malachy grasped both of them and took up the slack. Nothing happened. He increased the pressure. At once the patient jumped and said he felt pain. Malachy asked: 'Is it just in the skin?'. 'No', the patient replied, 'It's deep in my spine. It's my old pain coming back.'"
When Dr Smyth pulled even harder, the pain spread from the patient's back into the back of his leg and increased in severity. When he relaxed the nylon, the pain disappeared completely.
The first patient went home a week later. But before he left hospital, Malachy Smyth marked in indelible ink the path the pain followed when the nerve was stimulated.
The intrepid orthopaedic surgeon continued with his research. He repeated the same experiment on a further eight patients before turning to all the other nerves that protrude from the lumbar spine. Eventually, he was able to map out a pain pathway for each one.
He eloquently demonstrated the effects of a diseased intravertebral disc pressing on the nerve root behind it.
Dr Smyth went on to describe how the two small joints, called facet joints, on each side of the vertebral bone could also contribute to back pain.
"A patient tilts and rotates his spine to face the nerve root from the protruding disc. In doing so, he strains the small joints at the sides of the vertebral bone. This, in turn, causes severe pain in these small joints. The great muscles of the back then go into spasm to protect them."
Dr Smyth now believes the terms herniated and slipped disc should be abandoned. Why? Because he believes they conjure up a catastrophic event in people's minds which leads to many of the social and psychological problems associated with chronic back pain. His preferred term is: "cartilage cyst in a vertebral joint".
Dr Smyth's research was published in the Journal of Bone and Joint Surgery. In 1977, the seminal work was republished as a classic paper.
Many patients, this writer included, have reason to be thankful to Dr Smyth and the many specialists who have since refined lumbar disc surgery. It has made back surgery a less serious procedure, allowing patients return home a few days after the operation.
Dr Smyth's biography is an entertaining read for reasons other than his groundbreaking work on back pain. His stories of front-line medicine during the second World War are stark. Describing the treatment of young pilots whose entire backs were destroyed, he says: "It was like putting a sticking plaster onto a cancer wound."
A Life in Medicine by Aubrey Malone is published by Web Publications, priced €9.99. All proceeds from the sale of the book wil be donated to the Irish Red Cross.
Dr Muiris Houston is pleased to hear from readers at mhouston@irish-times.ie but regrets he cannot answer individual queries.