Patient’s Pedal Power Tests Knee Strength

Five Orthopaedic Surgeons at St John of God Murdoch Hospital, including Mr Mark Hurworth and Mr Gerald Lim from Murdoch Orthopaedic Clinic, have embarked on a study that will get patients pedalling on bicycles to measure the recovery of muscle function following knee replacement surgery.

This innovative idea was the brainchild of lead investigator Mr Mark Hurworth, who says there is currently no standard way to accurately and reliably test knee muscle function after knee arthroplasty (replacement) surgery.  “Common practice is to test muscle strength subjectively in the clinic,” Mr Hurworth says. “But we really need a more scientifically rigorous method to test muscle function and outcomes of the surgery.”

In the study, The Knee Stress Test, 90 patients who are undergoing total knee replacements at the hospital will use a bicycle with a power meter to test improvements in muscle power before and after surgery. They will take the pedal test pre-operatively and then at three, six and 12 months after surgery.  Participants will perform three sprint phases of 10 seconds separated by one-minute recovery phases using the InfoCrank power meter on a road bike attached to a stationary trainer.

“We are confident the bike power meter will prove to be a reliable and easy test and will help us identify those patients who are not recovering well,” Mr Hurworth says. “We will then be able to provide these patients with more rehabilitation to speed up their recovery from surgery.  Once we can show this is an effective measurement tool, we will be able to use it in future studies for other orthopaedic procedures such as knee surgeries, total hip replacements, as well as to investigate the effect of physiotherapy interventions.”