To study mobility in older populations it can be advantageous to use portable gait analysis systems, such as inertial measurement units (IMUs), which can be used in the community. To define a normal range, 136 active subjects were recruited with an age range of 18 to 97. Four IMUs were attached to the subjects, one on each thigh and shank. Subjects were asked to walk 10 m at their own self-selected speed. The ranges of motion of thigh, shank, and knee in both swing and stance phase were calculated, in addition to stride duration. Thigh, shank, and knee range of movement in swing and stance were significantly different only in the > 80 age group. Regressions of angle against age showed a cubic relationship. Stride duration showed a weak linear relationship with age, increasing by approximately 0.1% per year.
Monda, Goldberg, and Smitham are with the UCL Institute of Orthopaedics and Musculoskeletal Science, Royal National Orthopaedic Hospital, Middlesex, UK. Thornton is with the Royal National Orthopaedic Hospital, Middlesex, UK. McCarthy is with the Pedestrian Accessibility and Movement Environment Laboratory, University College London, London, UK. Address author correspondence to Ian McCarthy at email@example.com.