What is the CAUSE of bone and joint diseases?
The most effective way of tackling bone and joint problems is to get to the root of them, whether it is looking and biomarkers that show signs of disease development, or by taking specific precautions during physical activity that will reduce the chances of arthritis later in life. In order to develop effective prevention strategies, we must first have a better understanding of what the underlying causes of bone and joint disease are.
Pedometers for Spinal Stenosis
Christy Tomkins, PhD and her team of researchers representing Mount Royal University, University of Alberta, and University of Calgary are using pedometers to increase physical activity and decrease fat mass in people with lumbar spinal stenosis. The project “Spinal Stenosis Pedometer and Nutrition Lifestyle Intervention Randomized Trial” was awarded $98,968 through the CIHR Catalyst Grant in E-health Innovations award. Recruitment for the trial began in September 2013. Spinal stenosis is a narrowing of the open spaces within the spine, which can put pressure on the spinal cord and the nerves that travel through the spine. Spinal stenosis occurs most often in the neck and lower back.
Are Youth Who Suffer a Knee Joint Injury in Sport at Greater Risk of Developing OA and Poor Health Outcomes?
Osteoarthritis is a degenerative joint disease affecting 4.6 million Canadians. About 50% of joint injury suffered in youth during sport or recreational activity lead to OA. A study in youth with joint injuries may reveal important clues about how joint injury leads to OA. Joint injuries may impact joint structure, physical activity participation, adiposity, neuromuscular function, mental health, health care utilization and blood chemistry as early as 3-10 years following injury. Carolyn Emery, PhD and her team of interdisciplinary researchers have been awarded a three year $380,640 Canadian Institutes of Health Research grant. The research will provide a better understanding of the interaction between the physical, chemical, structural, and behavioral consequences of joint injury and how these relate to developing OA. Subjects for this study are youth and young adults (ages 15-26) who incurred a sport-related knee joint injury 3-10 years ago. How do young adults who sustained a knee injury differ in physical activity participation, fitness, body composition, blood chemistry, ability to perform movement tests and muscle structure compare to those who did not experience a knee injury? The team will also look at beliefs about injury, sport participation and health care use. This research project will generate new information that will help to reduce the individual, societal, and economic health burden of joint injury and OA disease.
Understanding the Biomechanics of the Joint
Research in the Tissue and Joint Mechanics Facility is seeking to enhance our understanding of how the various tissues in a joint (for example, a knee) transmit load while the joint is in motion. By comparing healthy joints to injured or diseased joints, we have begun to identify the exact loads carried by the four major ligaments, the two menisci and direct cartilage (cartilage contact in the knee) information that can be used to enhance therapeutic interventions, such as ligament reconstruction, which currently have mediocre success rates. Nigel Shrive, DPhil (Director of the McCaig Institute) and Cy Frank, MD (Clinician-Scientist, McCaig Institute) have established a highly accurate robotic testing platform that makes use of a novel parallel robot, called the Rotopod. This system allows for the replication of true joint specific motion, measured in vivo during normal gait and recreated ex vivo on the testing platform. This group is unique is that they have designed and fabricated an Instrumented Spatial Linkage (ISL) system with six degrees of freedom that can be used to record joint kinematics during normal treadmill gait, and subsequently for feedback to the robotic testing platform to reproduce those same motions in vitro.
Compared to traditional motion analysis equipment that uses surface markers for detection, this linkage system enables reduced processing times and accurate motion reproduction - within 0.1 mm and 0.1 degree of in vivo, about 10 times more accurate than any other system in the world. To date, the robotics equipment has been constructed, calibrated and validated using motion analysis data from healthy (intact) joints. Studies are currently underway to collect data from various joint injury and disease models, the first consisting of an arthroscopic anterior cruciate ligament (ACL) reconstruction model and an OA model. Currently, this group is the only one in the world that can do research on the knee using the Rotopod with this level of accuracy. The combination of this technology with the motion analysis system has put these researchers several years ahead of anyone else in their field. This work has led to more than a dozen publications and has allowed Shrive and Frank to secure numerous grants. For this work, Shrive’s team was awarded the AIF Research Excellence Summit Award, presented by The Association of Professional Engineers, Geologists and Geophysicists of Alberta.
Understanding the Role of Cartilage Cells
Cartilage cells play a crucial role in maintaining tissue integrity and it is well known that mechanical loading is one of the key regulators that influence the activity of these cells. Using a dual photon confocal microscope, Walter Herzog, PhD (CRC Chair in Molecular and Cellular Biomechanics and now Killam Memorial Professor) has created a novel system in which cartilage cell mechanics and signaling are measured in the intact knee of a live animal while the joint is loaded by controlled muscular contractions. This method offers a significant advantage over the traditional use of isolated cells, cartilage explants or fixed tissue samples, in which the natural tissue structure is lost. His group remains the only one in the world to measure chondrocyte deformation and signaling in the joint of a live animal. The technologies developed by Herzog will help us to understand the critical role that the cartilage cells play in maintaining tissue health, and how these functions alter as a result of excessive loading, injury or disease. A clear understanding of the function and behavior of cartilage cells will dramatically improve our ability to develop effective prevention strategies and novel therapeutics for a diversity of joint conditions. Herzog’s post-doctoral fellow won the Journal of Biomechanics Award for this work, which recognizes the best study presented at the American Society of Biomechanics, and Herzog was awarded the Borelli Award from the American Society of Biomechanics and the Career Award from the Canadian Society of Biomechanics; the two most prestigious awards from each society for his work on cartilage and muscle. He was also appointed fellow of the Royal Society of Canada, the highest honour attainable by scholars, artists and scientists in Canada.
Studying Human Motion
To examine how injury and disease affects human mobility, the McCaig Institute has established a state-of-the-art Human Motion Facility. In this facility, eight high-tech digital cameras are used to track surface markers attached to the skin of a patient, and joint motion at the hip, knee and ankle can be captured. Two force platforms are used to determine mechanical loading, a 16-channel electromyography (EMG) system uses surface electrodes to measure muscle activity during dynamic tasks, and a harness mounted to a ceiling track is used to study stability and falls. The goals of this research facility are: (i) to enhance the detection of early disease by monitoring changes in mobility, (ii) to identify risk factors and new disease modifying targets for OA and other bone and joint diseases, and (iii) to improve interventions in order to enhance care for those currently affected with bone and joint conditions. Using this equipment, Janet Ronsky, PhD (Canada Research Chair in Biomedical Engineering and recipient of two APEGGA AIF Summit Awards for Research Excellence and Excellence in Teaching) has investigated motion patterns from healthy individuals and those with joint injuries or total joint replacements in order to understand fundamental differences in mobility caused by disease and injury. A recent study by this group determined how lunging movements in ballet dancers could be incorporated into a training regime to reduce the risk of falls in average people. In a separate study, this group determined how movements and loading patterns differ between patients with gender specific and non-gender specific knee replacements. Ronsky’s group is currently studying human motion in healthy and anterior cruciate ligament (ACL)-deficient individuals over time, to determine changes in loading and gait following ACL injury. This information will be paired with MRI imaging of the knees to better understand how anatomical differences in the joint can affect mobility and movement.
In addition to the motion analysis equipment, a highly novel dual fluoroscopy system was designed and installed in this facility. This equipment can be used to collect highly accurate three-dimensional human joint dynamics together with ground impact forces from an instrumented treadmill.
The dual fluoroscopy system is highly sophisticated and flexible and is the only one of its kind in Canada, and among a handful in the world. It is currently being used to merge dynamic joint imaging with high-resolution medical images, including MRI, to create the first ever integrated investigation into joint biomechanics.