Compensations in lower limb joint work during walking in response to unilateral calf muscle weakness

Compensations in lower limb joint work during walking in response to unilateral calf muscle weakness

Waterval, Niels F.J. (Universiteit van Amsterdam)
Brehm, Merel Anne (Universiteit van Amsterdam)
Ploeger, Hilde E. (Universiteit van Amsterdam)
Nollet, Frans (Universiteit van Amsterdam)
Harlaar, J. (TU Delft Biomechatronics & Human-Machine Control; Vrije Universiteit Amsterdam)

2018

Background: Patients with calf muscle weakness due to neuromuscular disorders have a reduced ankle push-off work, which leads to increased energy dissipation at contralateral heel-strike. Consequently, compensatory positive work needs to be generated, which is mechanically less efficient. It is unknown whether neuromuscular disorder patients compensate with their ipsilateral hip and/or contralateral leg; and if such compensatory joint work is related to walking energy cost. Research question: Do patients with calf muscle weakness compensate for the increase in negative joint work by increasing positive ipsilateral hip work and/or positive contralateral leg work? And is the total mechanical work related with walking energy cost? Methods: Seventeen patients with unilateral flaccid calf muscle weakness and 10 healthy individuals performed the following two tests: i) a barefoot 3D gait analysis at comfortable speed and matched control speed (i.e. 0.4 non-dimensional) to assess lower limb joint work and ii) a 6-minute walk test at comfortable speed to assess walking energy cost. Results: Patients had a lower comfortable walking speed compared to healthy individuals (1.05 vs 1.36 m/s, p < 0.001) and did not increase positive lower limb joint work at comfortable speed. At matched speed (1.25 m/s), patients showed increased positive work at their ipsilateral hip (0.38 ± 0.08 vs 0.27 ± 0.07, p = 0.001) and/or contralateral leg (0.99 ± 0.14 vs 0.69 ± 0.14, p < 0.001). Patients with weakest plantar flexors used both strategies. No relation between total positive work and walking energy cost was found (r = 0.43, p = 0.122). Significance: Patients with unilateral calf muscle weakness compensated for reduced ankle push-off work by lowering their comfortable walking speed or, at matched speed, by generating additional positive joint work at the ipsilateral hip and/or contralateral leg. The additional positive joint work at matched speed did not explain the elevated walking energy cost at comfortable speed, which needs further exploration.

Ankle push-off
Gait compensations
Muscle weakness
Neuromuscular disorders
Walking energy cost

http://resolver.tudelft.nl/uuid:fd1c0c1c-71dc-4a9b-89f7-fcffff42cd1b

https://doi.org/10.1016/j.gaitpost.2018.08.016

2019-02-20

0966-6362

Gait & Posture, 66, 38-44

Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Institutional Repository

journal article

© 2018 Niels F.J. Waterval, Merel Anne Brehm, Hilde E. Ploeger, Frans Nollet, J. Harlaar