Letter to the Editor on “Summary measures for clinical gait analysis: A literature review” by V. Cimolin and M. Galli

Abstract

I read the recent article by Cimolin and Galli on ‘‘Summary measures for clinical gait analysis: A literature review’’ [1] with great interest. More and more gait laboratories use such summary measures to maximise the use of gait data but the complexity of the underlying mathematics often intimidates the end users. A comparative evaluation of simplified measures of gait deviation facilitates better comprehension of the various methods and therefore helps gait analysts make an informed choice of method. While the authors covered most gait summary measures in detail, it is unfortunate that the Movement Deviation Profile (MDP) was omitted. Its precursors were covered in the ‘‘Other summary measures’’ section but for the benefit of readers it is important to include the main study by Barton et al. [2] for completeness. The MDP meets many of the desirable criteria of a future method Cimolin and Galli [1] described in their conclusions. While it was created and tested with the same nine joint angle variables as the Gait Deviation Index (GDI), the MDP can use any waveform type data (angles, moments, EMG, etc.) even in combination. For example, the MDP was used to quantify the deviation of patients with shoulder instability using their 13-channel EMG [3]. An important advantage of the MDP is its immunity to an inaccurately defined gait cycle [2] which becomes a potential problem when direct measurement of foot contact is not available, for example when using only one force platform or inertia sensors in unrestricted gait analysis without foot contact sensors. I would be very interested to hear the authors’ and anyone else’s views on the above.