Mater Researchers shed light on knee replacement therapy

Thursday 21 September 2023

Queensland Researchers are trialing new light therapy patches as a non-invasive treatment for pain on patients who have had knee replacement surgery at Mater Hospital Brisbane.

In a bid to help patients get back on their feet faster and pain-free, Mater Research Associate Professor  Liisa Laakso is running an investigational study of the effects of photobiomodulation (PBM) therapy on post-operative pain and functional recovery involving 60 patients from Mater Hospital Brisbane.

The randomised study tests the effectiveness of a light-emitting adhesive patch that shines red and blue light on the knee joint and thigh muscle.

The device being investigated uses a novel, 3-D printed self-adhesive patch with hundreds of micro-diodes (light emitting diodes are found in many home appliances) that emit specific light frequencies that have been found in other research to reduce inflammation and pain, said Dr Laakso.

“Red and blue photons (tiny packets of light energy) are absorbed by the cells of the body and stimulate the cell’s powerhouse called the mitochondria.

“The mitochondria create the cell’s energy for its designated function. An example is the use of light to stimulate wound healing in skin cells.”

According to the 2022 Australian Orthopaedic Association National Joint Replacement Registry, more than 68,000 knee replacements were performed in Australia in 2022, however Dr Laakso said up to 20 per cent of patients undergoing a knee replacement experienced continuing pain that could occur for up to several months following surgery.

“The aim of the study is to see whether there is an improvement in inflammation and pain by using the treatment,” Dr Laakso said.

She said people with severe osteoarthritis were often reluctant or unable to exercise due to pain.

“We expect that a reduction in pain from the light therapy will increase people’s willingness to participate more in physical activity thus strengthening the muscles and improving activities of daily living,” Dr Laakso said.

In a related study, the Mater researchers are investigating whether the light treatment reduces pain and improves mobility in people with knee osteoarthritis who are not yet ready or suitable for knee replacement surgery.

“In both studies, participants self-apply the patches at home to standardised positions over the large muscle at the front of the thigh, and around the knee at each treatment; and remove the patches following each 30-minute daily treatment.

After suffering severe hip and knee osteoarthritis for four years Brisbane grandmother of six Janice Stockill joined the osteoarthritis study in July.

The 78-year-old, from Durack in Brisbane’s southwest, said she had experienced a “significant reduction” in pain from the light therapy patches.

“My pain is about a one out of 10 now. I can now walk for a start. I used to spend a lot of time in bed.

“The patches have really helped relieve my pain. In time to come I can easily flick the walking stick!”

Osteoarthritis is a chronic condition that causes inflammation and damage to the joints.

Dr Laakso said that in Australia, osteoarthritis was the most common form of arthritis.

“Eventually, the cartilage layer protecting the ends of bones wears away and new spikes of bone are formed,” she said.

“Without cartilage, the bones in the joint rub together, causing pain, swelling, stiffness and reduced movement.

“This can make walking, climbing stairs, or doing other daily activities harder. The condition can affect any joint in your body, but often the knees, hips, fingers, big toes, ankles and spine.

“It can worsen over time. Treatment includes regular exercise, healthy eating and weight loss, pain management, and surgery in more severe cases.”

Dr Laakso said participants involved in the study were visited at home one week before the scheduled surgery, one day before the surgery, and at one week, two weeks, four weeks, and six weeks after knee replacement surgery and again at 6 months and 12 months after surgery.

In total, each participant will have 17 treatments of 30 minutes over the course of the study.