Description of soft tissue artifacts and related consequences on hindlimb kinematics during canine gait

Abstract

Background Soft tissue artifacts (STAs) are a source of error in marker-based gait analysis in dogs. While some studies have revealed the existence of STAs in the canine hindlimb, STAs and their influence on kinematic gait analysis remain unclear. Methods Thirteen healthy Taiwan dogs affixed with twenty skin markers on the thigh and crus were recruited. Soft tissue artifacts and their influence on the determination of segment poses and stifle angles were assessed by simultaneously measuring marker trajectories and kinematics of the underlying bones via a model-based fluoroscopic analysis method. Results Markers on the thigh showed higher STAs than those on the crus, with root-mean-square amplitudes up to 15.5 mm. None of the tested marker clusters were able to accurately reproduce the skeletal poses, in which the maximum root-mean-square deviations ranged from 3.4° to 8.1°. The use of markers resulted in overestimated stifle flexion during 40–60% of the gait cycle and underestimated stifle flexion during 80–90% of the gait cycle. Conclusions Considerable magnitudes and effects of STAs on the marker-based 3D gait analysis of dogs were demonstrated. The results indicate that the development of error-compensation techniques based on knowledge regarding STAs is warranted for more accurate gait analysis.

An update on mobility assessment of dogs with musculoskeletal disease

“…Kinematic gait analysis data can be collected using specialised retroreflective skin markers and motion capture cameras (Lin et al 2020) to identify specific anatomical locations, most commonly: C7, T13, L7, dorsal spine of the scapula, acromion, medial and lateral humeral epicondyle, ulnar styloid, wing of the ilium, greater trochanter, medial and lateral femoral epicondyle, femorotibial joint, lateral malleolus of the distal tibia (Sandberg et al 2020). Markers are also frequently placed on the fifth metacarpal bone of the toe (Carr & Dycus 2016) (Fig 3).…”

“…A rigorous calibration process is required for kinematic gait analysis to establish a global coordinate system (GCS), thus, allowing retroreflective skin markers to be defined relative to body segments (Kirtley 2006). However, soft tissue artefacts often occur due to the displacement of the skin surface in relation to the underlying musculoskeletal structures during movement, commonly during flexion/extension, thus, significantly influencing the accuracy of the spatiotemporal data collected (Torres et al 2011, Schwencke et al 2012, Lin et al 2020. Furthermore, horizontal plane (cranial and caudal located) markers result in a greater degree of marker distance than those placed in a vertical plane (dorsal and ventral location) (Torres et al 2011).…”

“…2012, Lin et al . 2020). Furthermore, horizontal plane (cranial and caudal located) markers result in a greater degree of marker distance than those placed in a vertical plane (dorsal and ventral location) (Torres et al .…”