Full length articleGait patterns in association with underlying impairments in polio survivors with calf muscle weakness
Introduction
Poliomyelitis is a highly infectious viral disease that has left many polio survivors with permanent muscle weakness [1], often including the calf muscles. Gait in calf muscle weakness is typically characterized by instability of the ankle and knee [2], [3] and by an increased walking effort [2], [4], [5], which may hamper daily-life activities [6].
To compensate for loss of calf muscle function and improve gait, a dorsiflexion restricting ankle-foot orthosis (DR-AFO) can be provided. Dorsiflexion restriction aims to allow an external dorsiflexion moment around the ankle without causing instability [7], [8], [9], and it may reduce walking effort [10]. Previous research in polio survivors with calf muscle weakness, however, suggests that the efficacy of DR-AFOs to improve stability and reduce walking effort is partly dependent on the patients’ gait deviations when walking without an orthosis [10]. Hence, when prescribing a DR-AFO for calf muscle weakness, a clear understanding of the gait pattern deviations is important.
Gait pattern deviations due to calf muscle weakness have been previously investigated [7], [11], [12], [13], [14]. Yet, available studies lack a complete description of the joint kinetics of gait in addition to joint kinematics, while both contain important information of the resultant gait deviations and compensatory strategies. Furthermore, in most studies [11], [12], [13] gait was assessed in healthy subjects with a temporarily induced isolated calf muscle paralysis, while in polio survivors calf muscle weakness is rarely isolated, often not fully paralytic, and almost always accompanied with other lower extremity impairments such as muscle and joint contractures and bony deformities. Available gait descriptions in polio survivors have not yet been related to underlying impairments of the lower extremities, although the gait pattern may depend on these [4], [10]. Better insight in the gait pattern characteristics associated with calf muscle weakness is expected to help in the search for an optimal effective DR-AFO [7], [15].
The aims of this study in polio survivors with calf muscle weakness were to identify discrete gait patterns; relate the identified gait patterns to underlying impairments of the lower extremities; and determine whether, based on these underlying impairments, the gait pattern and single gait parameters could be predicted.
Section snippets
Study population
A retrospective search of the gait laboratory database at our university hospital outpatient Rehabilitation and Polio Expertise Center was conducted for selecting polio patients who had undergone barefoot three-dimensional (3D) gait analyses within a patient-care setting. Inclusion criteria for selecting patients were presence of muscle weakness in a single limb, presence of calf muscle weakness in that limb (defined as a score <5 according to the Medical Research Council (MRC) scale, and/or
Identification of gait patterns and impairment clusters
Seven of the eight possible gait patterns and all eight impairment clusters were identified (Fig. 1, Fig. 2). Five gait patterns contained the data of eight or more limbs, and each of these was connected to at least three impairment clusters. Most frequently identified (n = 23) was the least deviant gait pattern (gait pattern 1), to which seven impairment clusters were connected (Fig. 1). Next, gait pattern 5 (strongly deviant ankle angle and mildly/non-deviant ankle moment and knee angle) was
Discussion
In total, seven gait patterns were identified, with two dominant gait patterns present. These included the least deviant gait pattern 1 (32%), with patients presenting a mildly/non-deviant ankle angle, ankle moment and knee angle in midstance, and gait pattern 5 (25%), characterized by a strongly deviant ankle angle, and a mildly/non-deviant ankle moment and knee angle in midstance. There was a great variety in underlying impairments, both in degree and distribution of muscle weakness and
Conclusion
We observed a large heterogeneity in gait patterns and impairment profiles in polio survivors with calf muscle weakness. Polio survivors with a rather homogenous presentation of impairments do not necessarily walk in the same manner. From physical examination data, the gait pattern and single gait parameters could not be accurately predicted. Therefore, in the process of prescribing orthoses in polio survivors with calf muscle weakness, we propose that gait kinematics and kinetics should always
Funding
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Conflicts of interest statement
All authors declare that they have no conflict of interests with this publication.
Acknowledgements
We would like to thank the Dutch International Society of Prosthetics and Orthotics for a travel grant for H.E. Ploeger to visit Gillette Children's Specialty Healthcare in St Paul, MN in the USA (director of Bioengineering Research M.H. Schwartz) to train in the Random Forest Algorithm used in this paper.
References (30)
- et al.
How robust is human gait to muscle weakness
Gait Posture
(2012) - et al.
Contributions of the individual ankle plantar flexors to support, forward progression and swing initiation during walking
J. Biomech.
(2001) - et al.
Energy demands of walking in persons with postpoliomyelitis syndrome: relationship with muscle strength and reproducibility
Arch. Phys. Med. Rehabil.
(2006) - et al.
Disability and functional assessment in former polio patients with and without postpolio syndrome
Arch. Phys. Med. Rehabil.
(1999) - et al.
Ankle-foot orthoses that restrict dorsiflexion improve walking in polio survivors with calf muscle weakness
Gait Posture
(2014) - et al.
Inter-rater reliability for measurement of passive physiological movements in lower extremity joints is generally low: a systematic review
J. Physiother.
(2010) - et al.
Gait classification in children with cerebral palsy: a systematic review
Gait Posture
(2007) - et al.
Use of cluster analysis for gait pattern classification of patients in the early and late recovery phases following stroke
Gait Posture
(2003) - et al.
A case study of gait compensations for hip muscle weakness in idiopathic inflammatory myopathy
Clin. Biomech.. (Bristol, Avon)
(2007) - et al.
Do dynamic and static clinical measurements correlate with gait analysis parameters in children with cerebral palsy
Gait Posture
(2006)
Poliomyelitis: historical facts, epidemiology, and current challenges in eradication
Neurohospitalist
The relationship of lower extremity strength and gait parameters in patients with post-polio syndrome
Arch. Phys. Med. Rehabil.
Biomechanical abnormalities of post-polio patients and the implications for orthotic management
NeuroRehabilitation
Findings in post-poliomyelitis syndrome: weakness of muscles of the calf as a source of late pain and fatigue of muscles of the thigh after poliomyelitis
J. Bone Joint Surg. Am.
Orthoses for persons with postpolio syndrome
Cited by (25)
The effects of footplate stiffness on push-off power when walking with posterior leaf spring ankle-foot orthoses
2021, Clinical BiomechanicsCitation Excerpt :As such, we would like to demonstrate that the potential benefit of a posterior leaf spring in terms of energy storage and return may be maximized by optimizing footplate stiffness. Twelve healthy participants (7 male, mean (SD) age 24 (Rodda et al., 2004) years; height 175(0) cm; weight 71 (Ploeger et al., 2017) kg) were included in this study. All participants provided written informed consent in accordance with the procedures of the Institutional Review Board of the department of behavioral and movement sciences of VU University (Amsterdam, The Netherlands).
Polio survivors have poorer walking adaptability than healthy individuals
2021, Gait and PostureCitation Excerpt :Our results on stepping accuracy go a step further by also stratifying VE for most-affected and least-affected sides (Fig. 3b), yielding a poorer target-stepping accuracy for the least-affected (i.e. strongest) leg, possibly resulting from difficulties bearing weight on the most-affected (i.e., weaker) leg in the preceding single-support phase. Assumingly, foot placement with the least-affected leg is completed as quickly as possible to limit the effect of ankle and knee instability during single support with the most-affected leg [22]. A previous study in people after stroke reported equal foot-placement errors for the paretic and non-paretic side in both planned and reactive target stepping, possibly explained by both motor and neural deficits following a stroke [23].
Increased cerebral integrity metrics in poliomyelitis survivors: putative adaptation to longstanding lower motor neuron degeneration
2021, Journal of the Neurological SciencesCitation Excerpt :The cerebellum plays a key role in motor learning [89], and the coordination of a variety of functions including posture, balance, speech integrating inputs from the spinal cord and cortex. [90] Many polio patients acquired considerable physical disabilities such as leg length discrepancy, muscle atrophy, foot deformations and joint misalignments after the acute infection resulting in altered gait patterns. [91] Given the longstanding physical disability experienced by polio survivors, increased cerebellar grey matter volume and superior cerebellar white matter fibre organisation may represent an adaptive process to maintain gait and posture in face of lower extremity deformities, leg length discrepancies and lower motor neuron degeneration.