New publication from the APPROACH consortium describing the relationship between motion, using the GaitSmart® system, and radiographic knee osteoarthritis
Title
Relationship between motion, using the GaitSmartTM system, and radiographic knee osteoarthritis: an explorative analysis in the IMI-APPROACH cohort.
Authors
Eefje M van Helvoort, Diana Hodgins, Simon C Mastbergen, Anne Karien Marijnissen, Hans Guehring, Marieke Loef, Margreet Kloppenburg, Francisco Blanco, Ida K Haugen, Francis Berenbaum, Floris P J G Lafeber, Paco M J Welsing
Available here.
Objective
Currently, a lot of techniques are used to evaluate progression of osteoarthritis. All have their own strengths and limitations. Conventional x-rays are the gold standard, but lack the ability to directly visualize changes in articular cartilage. Besides, clinical symptoms might be present 2-3 years before changes on conventional x-rays appear. MRI does have the ability to visualize all joint tissues, including cartilage, but is very costly and therefore not suitable for standard use in clinical practice. Questionnaires, assessing pain and functional limitations reflect the subjective opinion of a patient rather than being an objective measurement for functional severity. Therefore, there is still an unmet need for non- or minimal invasive techniques, adding to the evaluation of osteoarthritis.
One of the possible techniques is motion analysis using the GaitSmart® system. It is a user-friendly and objective method to assess gait. It uses six sensors, that are attached to the body, after which patients have to walk 15-20m at their own self-selected speed. Then the sensors are connected to a laptop which analyzes the results. It takes about 10-15 minutes and can be carried out anywhere.
This study evaluated whether GaitSmart® has additional value in the evaluation of knee OA.
Methods
At first, we assessed whether GaitSmart® motion analysis evaluates the same thing as conventional x-rays and/or questionnaires, or maybe measures another feature of osteoarthritis. Secondly, we evaluated if GaitSmart® motion analysis is able to predict the presence of tissue damage on conventional x-rays and, if so, also gives information on the severity of this damage.
Results
Not surprisingly, different questionnaires (or subscales of questionnaires) measure almost the same features of knee OA. Also, different measures determined on the conventional X-rays measure overlapping features of knee OA. However, GaitSmart® was found to measure different features of OA and provides additional information on a patients disease status.
Next, we used patient demographics (age, gender, and BMI), questionnaires and GaitSmart® motion analysis, to predict the presence of tissue damage on a conventional x-ray. It was found that solely demographics, but also the combination of demographics and questionnaires poorly predict the presence of tissue damage on a conventional x-ray. Using demographics, questionnaires, and GaitSmart® motion analysis, improved the prediction to moderate. In other words, by using GaitSmart® motion analysis, in addition to demographics, and questionnaires, the prediction of having tissue damage on a conventional x-ray (yes or no) improves.
Lastly, we evaluated whether GaitSmart® motion analysis gives information not only on the presence of tissue damage (yes or no), but also on the severity of this tissue damage. It was found that GaitSmart® does give additional information on the severity of tissue damage as seen on conventional x-rays, but not as much as it does for the presence (yes or no) of damage on conventional x-rays.
Conclusions
GaitSmart® motion analysis measures additional features of a patients disease status, compared to conventional x-ray and questionnaires. In addition, it improves prediction of the presence of tissue damage as seen on a conventional x-ray.