Impaired Reactive Stepping in Stroke

Introduction[edit | edit source]

Individuals with stroke are at increased risk for falls, particularly so after hospital dischage. The ability to react to a balance perturbation is critical to maintain balance and prevent falls. Impaired reactive stepping is a prevalent problem for ambulatory patients with stroke preparing for discharge. A falls risk assessment should be carried out prior to discharge, including testing balance ability when perturbed and stepping reactions. In this way it is possible to identify those at risk for falls and to direct appropriate intervention strategies.

  • Knowledge of the locations of the limbs on the trunk and the head on the trunk is essential for making the correct transformations.
  • To achieve the dual goals of dynamic stability and appropriate orientation during movement, both anticipatory and reactive mechanisms are utilized. [1]

Mechanism[edit | edit source]

Compared to young individuals, elderly subjects more often rely on stepping strategies as opposed to ankle or hip strategies to recover balance following a postural perturbation[1]. So the ability to initiate a quick and efficient step is a critical factor for postural control in this population.

Stroke patients especially the elderly group demonstrates impaired anticipatory postural adjustments, delays in timing, an inability or unwillingness to initiate a step with the paretic limb, and the use of multi-step responses or the need for assistance to regain stability.

Clinical Assessment[edit | edit source]

Patients wear a safety harness attached to an overhead support

Reactive postural control mechanisms govern the fast, feedback-driven corrections that appropriately redirect foot placement when necessary. Reactive balance control is less frequently assessed.

  • Reactive stepping can be evaluated by using a "lean-and-release" balance perturbation method.
  • Patients need to wear a safety harness attached to an overhead support, and a physical therapist supervises to ensure safety. [2]

Training strategies for improving stepping in people with stroke[edit | edit source]

1. Neurodevelopmental approaches to improve stepping[edit | edit source]

The goal of treatment is a normal quality of gait and upper extremity movement. Emphasis is placed on bearing weight and using the extremities on the affected side to prevent learning to compensate with the intact side. As gait training begins, walking is accomplished with the aid of the therapist but without devices or bracing, encouraging the patient to bear weight and walk symmetrically. The philosophy of NDT is summarized in Berta Bobath’s statement that ‘it must always be remembered that the aim of this type of treatment is to improve the quality of movement on the affected side.’ … ‘In order to prepare for a reasonably normal gait, balance, stance and weight transfer should be practiced. If all this is first practiced while in the standing position, [the patient] will develop a better walking pattern than if he is made to walk immediately without the necessary control of his leg.’”

2. Task-Specific Training for Mobility[edit | edit source]

Salbach et al. (2004) demonstrated task-specific training of lower extremities designed to strengthen the lower extremities and enhance walking balance, speed, and distance showed improvement in a number of gait parameters[3].

3. Treadmill Training and Partial Weight Support[edit | edit source]

Treadmill training has been used as a form of gait specific training despite conflicting evidence as to whether or not it is more beneficial than standard gait training. Moseley et al. (2003) conducted a meta-analysis to determine the effectiveness of treadmill training and body weight support for walking after stroke. The authors found that, as compared to other physiotherapy interventions, treadmill training (with and without other task-oriented exercises) had no significant effects on walking speed. Nevertheless, there has been some indication that more aggressive progressive training programs may help to improve the effectiveness of treadmill training. For example, Pohl et al. (2002) found that stroke patients who received structured speed-dependent treadmill training scored significantly higher on measures of walking speed, cadence, stride length, and functional ambulation after 4 weeks of training[4].

Partial body weight support and treadmill training is a promising new approach that enables non-ambulatory stroke survivors the repetitive practice of complex gait cycles rather than single limb gait preparatory maneuvers.

4. Functional Electrical Stimulation in the Lower Extremity[edit | edit source]

Functional electrical stimulation (FES) in the lower extremity has been used to enhance ankle dorsiflexion during the swing phase of gait. Weak ankle dorsiflexion with plantarflexion hypertonicity results in a drop foot, which is typically corrected by an ankle-foot orthosis (AFO). FES of the common peroneal nerve during the swing phase of gait would appear to be a suitable alternative. Although not widely used or universally available, for highly motivated patients, able to walk independently or with minimal assistance, there is growing evidence that treatment with FES can improve dropped foot, which in turn can improve gait. Both implantable and surface electrodes may be used. A meta-analysis by [5]Glanz et al. (1996) including four RCTs (Bowman et al. 1979, Winchester et al. 1983, Merletti et al. 1978, Levin 1992), reported a favorable treatment effect associated with FES compared to a no treatment control. The effect size associated with a statistically significant change in paretic muscle force of contraction was 0.63 (95% CI 0.29, 0.98), although the clinical significance of this outcome is unclear. There were no other common outcomes among the four included studies.

5. Body weight supported treadmill training (BWSTT)[edit | edit source]

Body weight supported treadmill training (BWSTT) is a task-oriented technique for gait restoration after stroke. BWSTT has the advantage over conventional therapy as it offers higher intensity, more repetitive and task-oriented practice over the same period of time when compared to conventional therapy.[6]

BWSTT can significantly improve spatiotemporal parameters with three weeks of training. Improvement in gait pattern is related to the improvement of hip joint motion during walking. BWSTT is superior to conventional overground therapy in improving spatiotemporal parameters. Improvement in gait pattern is related to the improvement of kinematic pattern of proximal lower limb. Kinematic training of proximal lower limb may facilitate gait recovery.

Resources[edit | edit source]

https://www.frontiersin.org/articles/10.3389/fneur.2019.00711/full

References[edit | edit source]

  1. 1.0 1.1 Tseng, S. C., Stanhope, S. J., & Morton, S. M. (2009). Impaired reactive stepping adjustments in older adults. The journals of gerontology. Series A, Biological sciences and medical sciences64(7), 807–815. https://doi.org/10.1093/gerona/glp027
  2. Inness EL, Mansfield A, Lakhani B, Bayley M, McIlroy WE.Impaired reactive stepping among patients ready for discharge from inpatient stroke rehabilitation.Phys Ther. 2014 Dec;94(12):1755-64. doi: 10.2522/ptj.20130603. Epub 2014 Aug 7.
  3. Salbach NM, Mayo NE, Wood-Dauphinee S, Hanley JA, Richards CL, Côté R. A task-orientated intervention enhances walking distance and speed in the first year post stroke: a randomized controlled trial. Clin Rehabil. 2004 Aug;18(5):509-19. doi: 10.1191/0269215504cr763oa. PMID: 15293485.
  4. Pohl M, Mehrholz J, Ritschel C, Rückriem S. Speed-dependent treadmill training in ambulatory hemiparetic stroke patients: a randomized controlled trial. Stroke. 2002 Feb;33(2):553-8. doi: 10.1161/hs0202.102365. PMID: 11823669.
  5. Glanz M, Klawansky S, Stason W, Berkey C, Chalmers TC. Functional electrostimulation in poststroke rehabilitation: a meta-analysis of the randomized controlled trials. Arch Phys Med Rehabil 1996;77:549-53.
  6. Mao YR, Lo WL, Lin Q, Li L, Xiao X, Raghavan P, Huang DF. The Effect of Body Weight Support Treadmill Training on Gait Recovery, Proximal Lower Limb Motor Pattern, and Balance in Patients with Subacute Stroke. Biomed Res Int. 2015;2015:175719. doi: 10.1155/2015/175719. Epub 2015 Nov 16. PMID: 26649295; PMCID: PMC4663281.