New hope is on the horizon for people with back pain, one of the world’s leading causes of disability.
Four million Australians suffer from back pain – banana grower and Coffs Harbor mechanic Jaswir Grewal is one of them.
Jaswir has a decades-long history of crippling back pain caused by hard work, particularly the heavy lifting and bending required of an auto mechanic. In the past, pain reigned over her life and “took hold of everything.” He had three spinal fusion surgeries for ruptured lumbar discs, but they did not relieve his pain. Over time, Jaswir relied on increasing doses of oral opioids and fentanyl patches to get through the day, and he felt like he was “falling into a black hole.”
Jaswir eventually traveled to Sydney to visit the Michael J. Cousins Center for Pain Management and Research at the Royal North Shore Hospital. Jaswir was delighted that Australian pain medicine pioneer Professor Michael Cousins AO was his physician. He knew Professor Cousins had pioneered new back pain treatments and hoped there might be light at the end of the tunnel for him.
One pain management technique that Professor Cousins observed as it evolved was spinal cord stimulation, which first appeared in the 1970s. Pain specialists did not know not why spinal cord stimulators reduced back pain in some patients and not in others, but they believed that the current produced by the device reduced the constant state of increased reactivity or liquidation in the central nervous system people with chronic pain. .
Professor Cousins said that a major problem for researchers and pain specialists, even thirty years after the appearance of spinal cord stimulators, was that they did not know how much the stimulation relieved the pain. pain.
“In its early days, spinal cord stimulation was robust. It was a one-way system. You put on electrical pulses, but you didn’t know what happened to them unless the patient said, “Wow, this is great or this is terrible,” he said.
Another problem was that the stimulation often became too strong and could cause severe pain.
“When this happens,” explained Professor Cousins, “most patients decrease the volume of stimulation to avoid painful flare-ups, thereby reducing the pain relief they receive.”
He remembers a patient with a traditional spinal cord stimulator who used to grab a nearby wall or shelf to stand up whenever he coughed. Professor Cousins said he did it because he received massive overstimulation from a percussion wave passing through the spinal cord – the whipped spinal cord.
“His experience was like having a little electric shock. In some people, it caused them to fall because it hurt a lot. The patient ended up lowering the level of stimulation, reducing his pain relief, but preventing unwanted overstimulation.
Other patients have reported a throbbing sensation associated with their pacemaker. “The spinal cord contracts and swells with each heartbeat, which can increase stimulation to a painful level,” Professor Cousins said. “In some patients, older style pacemakers effectively shut off with every heartbeat. It meant it was on, off, on, off, on, off all the time. The pins and needles and the beat was the movement that the spinal cord superimposed on sensory input.
Yet thousands of people around the world have benefited from traditional spinal cord stimulation. In a 2011 interview with Australian doctorProfessor Cousins said in some patients, spinal stimulators provide a life-changing improvement. “This can prevent them from falling into the spiral of deterioration in mental and physical functioning that is so frequently seen in chronic pain.”
But, the devices have major limitations, and pain specialists don’t know why they help some patients and not others.
The limitations of traditional spinal cord stimulators worried Professor Cousins. So in 2009, he teamed up with scientist Dr John Parker to develop a more advanced form of spinal cord stimulation, which they said would solve the problems associated with traditional pacemakers. Several years of grueling early morning studies of sheep ensued in the bowels of a hospital at the Royal North Shore Hospital in Sydney. Once the new pacemaker, with a built-in feedback loop, was ready for patient testing, Professor Cousins and Dr Parker implanted it in a few patients for a week. It worked and provided essential information to further refine the device.
In 2015, during one of Jaswir Grewal’s appointments at the pain clinic, Professor Cousins told him about the closed-loop pacemaker. He explained the risks of the surgery and that the new device might not work.
“Would you like to try?” He asked. “You would be the first person in the world to have it.”
Jaswir nodded. He accepted the risk because if it helped him his life would be irrevocably changed for the better.
On October 13, 2015, pain specialist Dr. Charles Brooker implanted Jaswir’s device. Professor Cousins attended the proceedings. Before the operation, Jaswir said his pain was eight out of ten, but it was two out of ten after the operation.
“As soon as they turned it on, the pain in my back was gone,” Jaswir said. “It gave me instant mental relief.”
After Jaswir’s operation, Professor Cousins supported him as he slowly reduced his opioid use. Now he’s thrilled to be completely drug free.
“The pacemaker took control of my pain,” Jaswir said. “It does all the work of the opiates and other pain relievers that I took. My spinal cord stimulator is the best thing that has ever happened to me.
Dr Charles Brooker said that unlike previous spinal cord stimulators, closed-loop technology feeds back signals from the body to help guide treatment.
“The machine can adjust to produce any level defined by the patient,” he said. “This is a big step forward because before, whenever people moved or their hearts beat, various things made the electrical signal oscillate quite significantly. They would get feelings of shock and not be able to effectively live their lives in many cases. “
“It was a real Eureka moment in pain medicine!” said Professor Cousins. “Conventional implants are blind to what’s going on. They send a signal. They can talk, but they cannot listen. In comparison, the closed-loop device allows two-way conversation. It is the first device where the stimulus adjusts in response to feedback from the patient’s nervous system, optimizing the level of pain relief. So, by listening, the device regulates the amount of stimulus to match the pain level, providing a dose of pain relief tailored to the patient’s needs at that time.
Repeated studies around the world have shown that closed loop pacemakers provide significant pain relief in the majority of patients 18 months after implantation. These studies found that overstimulation, shocks and bangs do not occur with a closed loop system, allowing patients to maintain a constant flow of stimulation and pain relief, even when coughing.