Mechanical Biomarkers to Assess Knee Function

The knee is one of the largest and most complex joints in the human body. An injury or knee pain most often leads to loss of mobility and the reduction or termination of sports activities. In addition, people with knee problems use more medication and are more likely to suffer from depression. The WHO predicts that the prevalence of knee pathologies will increase by 40% by the year 2025.

Meanwhile, a lack of tools to assess knee function results in poor management of patients experiencing knee pain. Diagnostic tests are based on static imaging tests, often non-weight bearing, and only provide information on structural integrity. In order to identify the cause of pain, it is vital to assess the functional state of the knee. Researchers at the Marcelle-Gauvreau Engineering Research Chair in Mechanical Biomarkers intend to fill this gap. With the tool they developed to assess knee kinematics in patients with osteoarthritis—the KneeKGTM or Knee Kinesiography—they plan to extend this tool to other knee conditions. 

Biomarkers, the Basis of Dynamic Motion Analysis

The term biomarker, originally used in cell biology, refers to “a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes or pharmacological responses to a therapeutic intervention.” Transposed to the science of motion, a mechanical biomarker becomes a characteristic in a patient’s movements, observable only in affected individuals.

The KneeKGTM allowed the Chair researchers to identify the mechanical biomarkers of knee osteoarthritis by analyzing the kinematic curves of walking. More specifically, these biomarkers are maxima, minima and slopes extracted from each curve of knee motions.

In addition to an objective assessment of knee function, these biomarkers make it possible to direct treatment by supplying physiotherapists or kinesiologists with accurate information on specific problems based on the patient’s own biomechanics. Biomarkers also make it possible to measure the progress and ascertain the relevance of a treatment.

Chair Researchers Targeting New Biomarkers

Nicola Hagemeister, professor in the Systems Engineering Department and chairholder of Marcelle-Gauvreau Engineering Research Chair in Mechanical Biomarkers

Future work with the Chair will be focused on discovering clinically significant biomarkers for other knee conditions, such as ligament rupture and patellofemoral syndrome. To achieve this, the researchers will analyze walking patterns of subjects suffering from these pathologies and compare them to the patterns of healthy subjects. 

Biomarkers to better plan knee replacement surgeries will also be studied in order to better customize prostheses and restore the knee to its original function rather than its morphology.

The discovery of these types of biomarkers promises more efficient support for patients with knee pain and a revolution in the management of these pathologies.