Above (left to right): Olivia Samotus, PhD candidate; Larry Walleyn, research participant; and Dr. Mandar Jog
After being diagnosed with Parkinson’s disease in 2002, Larry Walleyn developed gait freezing. He had a hard time getting around, sometimes he couldn’t move at all and falls were frequent. His symptoms caused him to lose much of his independence.
Gait freezing is a symptom of Parkinson’s disease. It hinders the ability to produce continuous stepping movements. Freezing is unpredictable, which increases the risk of falls and injuries. Freezing episodes can be as short as a few seconds or can last hours.
A year ago, Larry became the first patient in Canada to undergo spinal cord stimulation (SCS) surgery to improve mobility in a study led by Lawson scientist Dr. Mandar Jog. In this surgery, two leads that send out electrical pulses are placed along the spinal cord in a patient’s lower back. A handheld device can control the frequency and strength of the electrical pulses.
After receiving the surgery, Larry says he saw a “huge improvement.”
According to Larry’s wife, Brenda Alderson, “As soon as they turned on the device for the first time, his walking improved and he wasn’t freezing as much. It kept getting better as time went on. Now I have a hard time keeping track of where he is sometimes!”
As part of this study, four other patients with advanced Parkinson’s disease have received the surgery, performed at London Health Sciences Centre (LHSC)’s University Hospital by Dr. Andrew Parrent, Lawson scientist and Chief of Neurosurgery at LHSC.
After the surgeries, Dr. Jog and his team then personalized the settings for the SCS over six months. The participants walked along a gait carpet wearing a motion capture body suit that allows the researchers to analyze all aspects of their gait, from head to toe. Using this data, they ensure the SCS is individualized to each patient’s gait dysfunction.
The five participants experienced an average decrease in the number of freezing episodes from 16 to 0 over 6 months, and showed significant improvements in walking speed and length of steps.
“Gait freezing limits the ability to perform daily activities so the improvements we’ve seen from SCS have really meant a better quality of life for these patients. For example, one patient was wheelchair bound before the study and now only uses it for long distances,” says Dr. Jog, who is also a neurologist at LHSC and a professor at Western University’s Schulich School of Medicine & Dentistry. “Considering gait freezing usually goes untreated, the potential for SCS to help patients with advanced Parkinson’s disease is very exciting.”
Oral medications have no impact on gait for many patients. Deep brain stimulation (DBS) surgery often provides minimal to no change in gait and only a fraction of patients are eligible for the surgery. In comparison to DBS surgery, SCS is minimally invasive and less risky, which would allow a wide range of patients to undergo the treatment.
The study in London, Ontario led by Dr. Jog is the first to use objective measures of gait and whole-body movements to better tailor SCS to each patient’s symptoms. With the five patients who participated in this study, a total of 33 human case studies on SCS have been published around the world.
“More research is needed to understand the full effects of SCS in improving gait dysfunction,” adds Dr. Jog.
Dr. Jog and his team plan on treating 20 more patients over the next three years, and will study changes to brain and spinal activity over a one-year period of using SCS.