April 2012

Orthotic considerations for foot drop after stroke

Figure 1. Dynamic ankle orthosis

When prescribing an ankle foot orthosis or neuroprosthesis for a patient with acute drop foot following stroke, lower extremity practitioners should consider the device’s potential effects on neural plasticity and motor relearning in addition to its potential effects on gait.

By Chad Lairamore, PhD, PT, CBISt

Cerebrovascular accident (CVA) is a leading cause of disability in the US1 and frequently results in hemiparesis, impairing the patient’s ability to ambulate.2-5 The hemiparesis often affects dorsiflexion of the ankle, resulting in foot drop and decreased gait velocity.2-5

One method often employed to treat foot drop is the use of an ankle foot orthosis (AFO).  AFOs have been shown to provide many benefits for improving hemiparetic gait, including increased gait velocity,5-14 a more symmetrical gait pattern, improved foot clearance during swing,6,9,11,13,15 and decreased energy expendi­ture.8,12 Traditionally, a definitive custom plastic AFO is not prescribed until improvements in gait have reached a plateau, four to six months after CVA, as recommended by McCollough et al.16

This raises the question of what should be done to treat foot drop when an individual is in the initial recovery phase following CVA. Some authors have suggested using a hinged metal upright AFO during the initial recovery period to allow therapeutic adjustments to the AFO as the patient improves.16 A rigid Valens AFO also has been suggested as an integral part of CVA rehabilitation.15 However, many practitioners are reluctant to prescribe an AFO for patients with an acute stroke out of fear that using an orthosis encourages disuse of the tibialis anterior muscle, which may result in long-term dependence on bracing.15,17

The tibialis anterior muscle contributes significantly to control of the foot during the loading and swing phases of the gait cycle.18,19 Persistent impairments in the ability to contract the tibialis anterior muscle result in foot drop or foot slap and cause subsequent gait abnormalities.18 During the swing phase of gait the tibialis anterior muscle is maximally contracted to dorsiflex the foot and maintain dorsiflexion throughout the swing phase, providing foot clearance as the leg is advanced.18,19 If an individual is unable to contract the tibialis anterior muscle sufficiently they will exhibit foot drop and have difficulty advancing the leg and may exhibit excessive hip flexion, circumduction, lateral trunk lean, or vaulting to advance the limb.18 During the loading phase of gait the ankle plantar flexes and the tibialis anterior muscle is eccentrically active to control the rate of plantar flexion.18,19 If the tibialis anterior muscle is weak, an individual will exhibit foot slap, which disrupts the heel rocker, forward progression, and shock absorption.18

Several studies have demonstrated a decrease in tibialis anterior muscle activity during gait with use of an AFO. Hesse et al15 recorded a decrease in tibialis anterior muscle activation when individuals post-CVA walked with a rigid AFO compared with walking without an AFO. Geboers et al17 found an immediate decrease in tibialis anterior muscle firing when a rigid AFO was used in healthy individuals and those with peripheral paresis. A study by Crabtree and Higginson20 confirmed these clinical findings through an AFO computer model that predicted torque based on ankle angle and velocity during walking. The authors estimated tibialis anterior muscle activity would decrease across the entire gait cycle with use of a posterior leaf AFO.20 These studies support practitioners’ notions that use of an AFO may lead to decreased use of the tibialis anterior muscle.

Using functional magnetic resonance imaging, current research regarding CVA recovery has demonstrated plasticity of cortical areas of the brain related to walking.21-24 A major construct of neural plasticity for promotion of motor relearning is to use the affected limb after an upper motor neuron injury.25-28 In fact, the first two principles of experience-dependent plasticity espoused by Kleim and Jones are simply stated as: “use it or lose it” and “use it and improve it.”29 These principles of neuroplasticity suggest that use of an orthosis and the resulting decrease in muscle activity will likely result in a decreased opportunity for motor relearning during the recovery phase after CVA. This potential decrease in opportunity for motor relearning may make practitioners reluctant to use an orthosis for patients with an acute CVA.

Dynamic ankle orthosis

Clinicians have attempted to design orthoses to provide ankle stability and dorsiflexion while minimizing the effects on decreasing muscle recruitment during gait to prevent learned nonuse.30 Included in this group of orthoses is the dynamic ankle orthosis (DAO) (Figure 1).30 A DAO is constructed from Polyflex II and consists of a calcaneal foot plate, a short medial upright, and a cuff.  It theoretically provides medial ankle stability and a proper base of support for weight acceptance, allows for normal tibial advance­ment during stance phase of gait, and assists in foot clearance during swing phase.30

Researchers from the University of Central Arkansas in Conway recruited 15 poststroke individuals who were recently discharged from inpatient rehabilitation to investigate the effects of DAO usage on hemiplegic gait. All participants were six months or less poststroke (mean days poststroke, 86.3 ± 50.41; range, 16-208 days). Investigators used a repeated measure design and participants walked at a self-selected speed under three conditions: wearing a DAO, wearing a posterior leaf spring AFO, or wearing no orthosis. Three-dimensional motion analysis and electromyography (EMG) of the tibialis anterior muscle were performed.

The findings, published in December in Prosthetics & Orthotics International, demonstrated a significant decrease in tibialis anterior muscle EMG activity during the swing phase of gait with the DAO compared with walking without an AFO.31 This suggests that even though the DAO is designed to be less restrictive than traditional AFOs, that design does not translate into increased tibialis anterior muscle activity during gait. In fact, there was no difference in muscle activity between the DAO and the posterior leaf spring AFO. While the DAO has a short footplate, functionally it is coupled with the shoe, and together they provide sagittal plane stability and subsequently reduce demand on ankle dorsiflexors.

Clinicians should take the decrease in tibialis anterior muscle activity into consideration. The decrease in muscle activity suggests that individuals recovering from a CVA may have less opportunity for motor relearning compared with walking without an orthosis. Yet clinicians should also consider the potential benefits of orthosis usage as well as the potential for an increase in the amount of walking which could offset any decrease in tibialis anterior activity.

Carbon fiber AFOs

Another type of AFO commonly used clinically for patients with foot drop following stroke is a carbon fiber AFO. A carbon fiber AFO stores energy throughout stance and has a spring-like effect, increasing the plantar flexion moment and power generation during push off.32-34 Additionally, use of this type of AFO in a population with chronic stroke has been shown to increase gait speed and decrease energy required to ambulate.35,36 However, research has shown the use of a carbon fiber AFO directly takes over the work of the ankle.35

Figure 2. Bioness L300

As with use of the DAO, the reduced demand on the ankle musculature may result in decreased opportunity for motor relearning, and clinicians should consider this when treating a patient during the initial recovery phase after a CVA. Conversely, it is plausible that use of a carbon fiber orthosis, which increases the capacity for gait by decreasing energy demand, may be more beneficial than walking without an AFO. Currently, there is limited research on carbon fiber AFOs and their use as a modality during rehabilitation and there is a need for longitudinal studies investigating the effect of carbon fiber AFO usage on relearning gait to inform clinical decision-making.

Functional electrical stimulation

Another method gaining popularity for eliciting dorsiflexion during gait in individuals with CVA is functional electrical stimulation (FES). FES is a technique in which a small electrical current is applied to the peroneal nerve and the tibialis anterior muscle during the swing phase of gait to elicit a contraction of the tibialis anterior muscle when the foot is advanced. Studies have shown the use of FES for its orthotic effect as a neuroprosthesis increases gait velocity, decreases the physiological demand of walking, improves gait symmetry, increases balance during gait, and improves social integration for individuals with CVA.37-46

In addition, use of FES has demonstrated a therapeutic effect on walking performance up to 11 months after its use in patients with chronic CVA.44,45 FES has been shown to facilitate normal tibialis anterior muscle electromyography and improve gait velocity in individuals with CVA.40,42,47 Additionally, long-term use of FES increases activation of motor cortical areas in the brain.48 It has also been suggested that regular use of FES can improve control over voluntary neural motor pathways and inhibit abnormal reflexes.49 Additionally, Dimitrijevic et al50 and Weingard et al51 both suggest use of FES during early gait training may promote motor relearning.

In a recent unpublished study investigating the effects of FES on tibialis anterior muscle activity, researchers from the University of Central Arkansas performed a single-blinded randomized controlled trial with 26 participants. All participants had foot drop secondary to an acute nonprogressive neurological injury and were enrolled in an acute inpatient rehabilitation facility. Participants were divided into two groups: one received FES during gait training and the other received sham stimulation during gait training. For the duration of the participants’ stay in the facility, FES or sham FES was administered during gait training three times a week in 45-minute sessions. Investigators used the Bioness L300 (Figure 2) to administer stimulation to the FES group as well as minimal sensory stimulation over the tibia to the sham stimulation group. Before and after intervention researchers evaluated EMGs of the tibialis anterior muscle and spatiotemporal gait parameters as participants walked 10 feet. The therapeutic effect of the FES was in question, therefore participants were tested without use of the FES in pre- and post-testing.

Although there were no differences between groups at the onset of the study, the researchers found the group receiving FES exhibited significantly more tibialis anterior muscle activity during the swing phase of gait at the end of the study compared with the sham stimulation group. Given the evidence suggesting use of an orthosis decreases tibialis anterior muscle activity, the FES-facilitated increase in tibialis anterior muscle activity may play a role in improving motor relearning as opposed to performing gait training without FES or with an orthosis.

Another option for individuals with decreased ankle stability is to use FES in combination with an AFO.  Frequently individuals with hemiparesis demonstrate mediolateral ankle instability during stance in conjunction with foot drop during swing. For these individuals it may be beneficial to use an AFO in conjunction with FES, as the technique does not provide stimulation or stability during the stance phase of gait.

FES improves gait and foot clearance without diminishing tibialis anterior muscle activity, but it is not for everyone. Currently, there is minimal insurance coverage for an FES neuroprosthesis, and the cost is significantly greater than that of an AFO and may be prohibitive for many individuals. In addition, the tingling sensation associated with FES is not tolerated well by all individuals and contraindications, such as a demand-type pacemaker or excessive edema, may also limit use.


When making decisions about prescribing a device for treating foot drop during the initial recovery phase after a CVA one should consider how the orthosis or neuroprosthesis will influence recovery and brain plasticity, in addition to its effect on gait. Although further longitudinal studies are needed, the most recent literature suggests FES can provide foot clearance and improve gait characteristics while promoting motor relearning.

In situations in which a patient requires use of an orthosis, clinicians should consider the potential for decreased tibialis anterior muscle activity that can be associated with device use. Conversely, clinicians should also consider the benefits of different orthoses, including the possibility that orthosis use can be associated with increased activity levels and improved symmetry of gait, which could offset any decrease in muscle activity.

Chad Lairamore, PhD, PT, CBISt, is assistant professor at the University of Central Arkansas in Conway, and a physical therapist at Baptist Health Rehabilitation Hospital in Little Rock, AR.

Disclosure: The author has no affiliation with products, devices, or companies mentioned in the article.

  1. Lloyd-Jones D, Adams RJ, Brown TM, et al. Heart disease and stroke statistics—2009 update: a report from the American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Circulation 2009;119(7):e21-e181.
  2. DeQuervain IA, Simon S, Leurgans S, et al. Gait pattern in the early recovery period after stroke. J Bone Joint Surg Am 1996;78(10):1506-1514.
  3. Fish D, Kosta CS. Walking impediments and gait inefficiencies in the CVA patient. JPO 1999;11(2):33-37.
  4. Lehmann JF. Push-off and propulsion of the body in normal and abnormal gait. Correction by ankle-foot orthoses. Clin Orthop Relat Res 1993;(288):97-108.
  5. Lehmann JF, Condon SM, Price R, deLateur BJ. Gait abnormalities in hemiplegia: their correction by ankle-foot orthoses. Arch Phys Med Rehabil 1987;68(11):763-771.
  6. Caillet F, Mertens P, Rabaséda S, Boisson D. Three dimensional gait analysis and controlling spastic foot on stroke patients. Ann Readapt Med Phys 2003;46(3):119-131.
  7. Corcoran PJ, Jebsen RH, Brengelmann GL, Simons BC. Effects of plastic and metal leg braces on speed and energy cost of hemiparetic ambulation. Arch Phys Med Rehabil 1970;51(2):69-77.
  8. Franceschini M, Massucci M, Ferrari L, et al. Effects of an ankle-foot orthosis on spatiotemporal parameters and energy cost of hemiparetic gait. Clin Rehabil 2003;17(4):368-372.
  9. Gök H, Küçükdeveci A, Altinkaynak H, et al. Effects of ankle-foot orthoses on hemiparetic gait. Clin Rehabil 2003;17(2):137-139.
  10. Mojica JA, Nakamura R, Kobayashi T, et al. Effect of ankle-foot orthosis (AFO) on body sway and walking capacity of hemiparetic stroke patients. Tohoku J Exp Med 1988;156(4):395-401.
  11. Rao N, Chaudhuri G, Hasso D, et al. Gait assessment during the initial fitting of an ankle foot orthosis in individuals with stroke. Disabil Rehabil Assist Technol 2008;3(4):201-207.
  12. Tyson SF, Thornton HA. The effect of a hinged ankle foot orthosis on hemiplegic gait: objective measures and users’ opinions. Clin Rehabil 2001;15(1):53-58.
  13. Wang RY, Lin PY, Lee CC, Yang YR. Gait and balance performance improvements attributable to ankle-foot orthosis in subjects with hemiparesis. Am J Phys Med Rehabil 2007;86(7):556-562.
  14. Wang RY, Yen L, Lee CC, et al. Effects of an ankle-foot orthosis on balance performance in patients with hemiparesis of different durations. Clin Rehabil 2005;19(1):37-44.
  15. Hesse S, Werner C, Matthias K, et al. Non-velocity-related effects of a rigid double-stopped ankle-foot orthosis on gait and lower limb muscle activity of hemiparetic subjects with an equinovarus deformity. Stroke 1999;30(9):1855-1861.
  16. McCollough NC. Orthotic management in adult hemiplegia. Clin Orthop Relat Res 1978(131):38-46.
  17. Geboers JF, Drost MR, Spaans F, et al. Immediate and long-term effects of ankle-foot orthosis on muscle activity during walking: a randomized study of patients with unilateral foot drop. Arch Phys Med Rehabil 2002;83(2):240-245.
  18. Perry J, Burnfield J. Gait analysis: Normal and pathological function. 2nd ed. Thorofare, NJ: Slack Inc; 2010.
  19. Anderson FC, Pandy MG. Individual muscle contributions to support in normal walking. Gait Posture 2003;17(2):159-169.
  20. Crabtree CA, Higginson JS. Modeling neuromuscular effects of ankle foot orthoses (AFOs) in computer simulations of gait. Gait Posture 2009;29(1):65-70.
  21. Enzinger C, Johansen-Berg H, Dawes H, et al. Functional MRI correlates of lower limb function in stroke victims with gait impairment. Stroke 2008;39(5):1507-1513.
  22. Daly JJ, Ruff RL. Construction of efficacious gait and upper limb functional interventions based on brain plasticity evidence and model-based measures for stroke patients. Scientific World J 2007;7:2031-2045.
  23. Dobkin BH, Firestine A, West M, et al. Ankle dorsiflexion as an fMRI paradigm to assay motor control for walking during rehabilitation. Neuroimage 2004;23(1):370-381.
  24. Uy J, Ridding MC, Hillier S, et al. Does induction of plastic change in motor cortex improve leg function after stroke? Neurology 2003;61(7):982-984.
  25. Schaechter JD, Kraft E, Hilliard TS, et al. Motor recovery and cortical reorganization after constraint-induced movement therapy in stroke patients: a preliminary study. Neurorehabil Neural Repair 2002;16(4):326-338.
  26. Sunderland A, Tuke A. Neuroplasticity, learning and recovery after stroke: a critical evaluation of constraint-induced therapy. Neuropsychol Rehabil 2005;15(2):81-96.
  27. Krakauer JW. Motor learning: its relevance to stroke recovery and neurorehabilitation. Curr Opin Neurol 2006;19(1):84-90.
  28. van der Lee JH. Constraint-induced movement therapy: some thoughts about theories and evidence. J Rehabil Med 2003;(41 Suppl):41-45.
  29. Kleim JA, Jones TA. Principles of experience-dependent neural plasticity: implications for rehabilitation after brain damage. J Speech Lang Hear Res 2008;51(1):S225-S239.
  30. Nawoczenski DA, Epler ME. Orthotics in functional rehabilitation of the lower limb. 6th ed. Philadelphia: Saunders WB; 1997.
  31. Lairamore C, Garrison MK, Bandy W, Zabel R. Comparison of tibialis anterior muscle electromyography, ankle angle, and velocity when individuals post stroke walk with different orthoses. Prosthet Orthot Int 2011;35(4):402-410.
  32. Desloovere K, Molenaers G, Van Gestel L, et al. How can push-off be preserved during use of an ankle foot orthosis in children with hemiplegia? A prospective controlled study. Gait Posture 2006;24(2):142-151.
  33. Bartonek A, Eriksson M, Gutierrez-Farewik EM. Effects of carbon fibre spring orthoses on gait in ambulatory children with motor disorders and plantarflexor weakness. Dev Med Child Neurol 2007;49(8):615-620.
  34. Wolf SI, Alimusaj M, Rettig O, Döderlein L. Dynamic assist by carbon fiber spring AFOs for patients with myelomeningocele. Gait Posture 2008;28(1):175-177.
  35. Bregman DJ, Harlaar J, Meskers CG, de Groot V. Spring-like ankle foot orthoses reduce the energy cost of walking by taking over ankle work. Gait Posture 2012;35(1):148-153.
  36. Danielsson A, Sunnerhagen KS. Energy expenditure in stroke subjects walking with a carbon composite ankle foot orthosis. J Rehabil Med 2004;36(4):165-168.
  37. Burridge JH, Taylor PN, Hagan SA, et al. The effects of common peroneal stimulation on the effort and speed of walking: a randomized controlled trial with chronic hemiplegic patients. Clin Rehabil 1997;11(3):201-210.
  38. Hausdorff JM, Ring H. Effects of a new radio frequency-controlled neuroprosthesis on gait symmetry and rhythmicity in patients with chronic hemiparesis. Am J Phys Med Rehabil 2008;87(1):4-13.
  39. Kesar TM, Perumal R, Jancosko A, et al. Novel patterns of functional electrical stimulation have an immediate effect on dorsiflexor muscle function during gait for people poststroke. Phys Ther 2009;90(1):55-66.
  40. Kottink AI, Oostendorp LJ, Buurke JH, et al. The orthotic effect of functional electrical stimulation on the improvement of walking in stroke patients with a dropped foot: a systematic review. Artif Organs 2004;28(6):577-586.
  41. Laufer Y, Hausdorff JM, Ring H. Effects of a foot drop neuroprosthesis on functional abilities, social participation, and gait velocity. Am J Phys Med Rehabil 2009;88(1):14-20.
  42. Laufer Y, Ring H, Sprecher E, Hausdorff JM. Gait in individuals with chronic hemiparesis: one-year follow-up of the effects of a neuroprosthesis that ameliorates foot drop. J Neurol Phys Ther 2009;33(2):104-110.
  43. Ring H, Treger I, Gruendlinger L, Hausdorff JM. Neuroprosthesis for footdrop compared with an ankle-foot orthosis: effects on postural control during walking. J Stroke Cerebrovasc Dis 2009;18(1):41-47.
  44. Robbins SM, Houghton PE, Woodbury MG, Brown JL. The therapeutic effect of functional and transcutaneous electric stimulation on improving gait speed in stroke patients: a meta-analysis. Arch Phys Med Rehabil 2006;87(6):853-859.
  45. Stein RB, Everaert DG, Thompson AK, et al. Long-term therapeutic and orthotic effects of a foot drop stimulator on walking performance in progressive and nonprogressive neurological disorders. Neurorehabil Neural Repair 2010;24(2):152-167.
  46. Taylor PN, Burridge JH, Dunkerley AL, et al. Clinical use of the Odstock dropped foot stimulator: its effect on the speed and effort of walking. Arch Phys Med Rehabil 1999;80(12):1577-1583.
  47. Daly JJ, Roenigk K, Holcomb J, et al. A randomized controlled trial of functional neuromuscular stimulation in chronic stroke subjects. Stroke 2006;37(1):172-178.
  48. Everaert DG, Thompson AK, Chong SL, Stein RB. Does functional electrical stimulation for foot drop strengthen corticospinal connections? Neurorehabil Neural Repair 2010;24(2):168-177.
  49. Thompson AK, Estabrooks KL, Chong S, Stein RB. Spinal reflexes in ankle flexor and extensor muscles after chronic central nervous system lesions and functional electrical stimulation. Neurorehabil Neural Repair 2009;23(2):133-142.
  50. Dimitrijevic MR. Clinical practice of functional electrical stimulation: from “Yesterday” to “Today”. Artif Organs 2008;32(8):577-580.
  51. Weingarden H, Ring H. Functional electrical stimulation-induced neural changes and recovery after stroke. Eura Medicophys 2006;42(2):87-90.

2 Responses to Orthotic considerations for foot drop after stroke

  1. mahmod says:

    please note that i have droop foot from the PERONEAL NERVE


  2. Tammy R Fleeman says:

    I have drop foot with inversion. It happened due to low back problems. Had L4 to S1 fused with 6 screws & 2 rods placed in my spine. The surgery did not help in curing the drop foot. Can’t wear ago or braces due to them causing pain. Will this help my foot drop and the inversion?

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.