Functional Electrical Stimulation to Improve Locomotor Function

Author Year; Country
Research Design
Sample Size
Methods Outcomes

Thrasher et al. 2006; Canada
Level 4

Population: 5 males and females; age 24-72 yrs; all participants had an incomplete SCI; C5-T12 lesion level; 2-24 yrs post-injury.
Treatment: Gait training regimen with FES neuroprosthesis 2-5x/week for 12-18 weeks. First 4-8 sessions consisted of lower limb muscle strengthening performed in 4 sets of 5 min with 5 min rest. Participants then performed walking exercises with the neuroprosthesis for 15-30 min/session (rest as needed) either on a treadmill or overground.
Outcome Measures: Walking speed, stride length, step frequency
  1. 4/5 participants significantly increased walking speeds (95% significance level). These 4 participants also significantly increased step frequency and stride length (95% significance level).

Ladouceur & Barbeau 2000a; Canada
Level 4
N=14 (enrolled)
N=10 (analyzed)

Population: 14 participants; age 25-49 yrs; all participants had an incomplete SCI; C3-L1 lesion level; 1.8-19.1 yrs post-injury,
Treatment: Surface FES: bilateral or unilateral common peroneal nerve, home use as much as possible ~1 year (26 and 56 weeks), 2 participants also had bilateral quadriceps.
Outcome measures: temporal gait measures.
  1. There were significant increases in mean walking speed (0.10 m/s, p=.007) and mean stride length (0.12 m, p=.065) both with and without FES over the first year of FES use.
  2. FES-assisted walking led to minor increases in mean walking speed, but these changes were not significant (p=.543).

Ladouceur & Barbeau 2000b; Canada
Level 4
N=14 (recruited)
N=10 (completed)

Population: 14 participants; age 25-49 yrs; all participants had an incomplete SCI; C3-L1 lesion level; 1.8-19.1 yrs post-injury
Treatment: Surface FES: bilateral or unilateral common peroneal nerve, 2 participants also had bilateral quadriceps, home use as much as possible ~1 year.
Outcome measures: temporal gait measures.
  1. 7/14 participants showed improvement based on type of ambulatory device.
  2. 13/14 participants improved gait speed with FES.
  3. Training/carryover effect after long-term use: increase evident even when FES off in 12/14 participants.

Wieler et al. 1999; Canada
Level 4

Population: 31 males and females; mean (SD) age 36(2) yrs; all participants had an incomplete SCI; mean(SD) 6(1) yrs post-injury.
Treatment: Surface FES: common peroneal nerve; some participants also received FES to hamstrings, quadriceps, gluteus medius, duration of FES ranged from 3 months to over 3 years. Each participant was tested at the start and end of the study both with and without FES.
Outcome measures: walking speed, stride length, cycle time
  1. There was a significant improvement in gait speed in participants when treated with FES (p<.01) but that improvement in gait speed persisted even when participants walked without FES (p<.01)
  2. The slowest quintile of participants increased their walking speed by 70% while the fastest quintile of participants increased their walking speed by 20%.
  3. The initial gait speed at the start of study was significantly faster when patients used FES than when no FES was used (p<.05)

Klose et al. 1997; USA
Level 4

Population: Mean (SD) age 28.4 (6.6) years; all participants had complete SCI; T4-T11 lesion level; 0.7-9.0 yrs post-injury
Treatment: Surface FES: Parastep: 6 channels (bilateral common peroneal nerve, quadriceps, glutei); 3X/week, 32 sessions (once participants had sufficient strength to stand).
Outcome measures: walking distance and speed (with FES).
  1. Most participants improved endurance and gait speed. Longest distance walked with FES was between 12 to 1707 m (mean: 334 m; SD 402 m).
  2. There were significant differences in distance travelled (p<.001) and gait speed (p<.001) over the 11 weeks.

Granat et al. 1993; Scotland
Level 4

Population: 6 males and females; age 20-40 yrs; all participants had diagnosis of Frankel C and D; C3-L1 lesion level; 2 to 18 yrs post-injury
Treatment: Surface FES: quadriceps, hip abductors, hamstrings, erector spinae, common peroneal nerve,
home program >30 min, 5X/week, 3 months.
Outcome measures: walking speed, stride length, cadence.
  1. Significant mean increase in stride length, but not speed or cadence.
  2. 3 to 4 participants had significant individual increases in gait speed, stride length and cadence.

Stein et al. 1993; Canada
Level 4

Population: 10 males and females; age 20-44 yrs; all participants had an incomplete SCI; C2-T10 lesion level; 2.5-10 years post-injury.
Treatment: Surface, percutaneous, or implanted FES of common peroneal nerve, and sometimes quadriceps, glutei, and psoas.
Outcome measures: speed, gait parameters.
  1. All participants improved gait speed when FES was on (mean change was 4 m/min)
  2. Participants with more severe SCI were the most receptive towards the FES treatment

Granat et al. 1992; Scotland
Level 4

Population: 3 males and 3 females; age 18-40 yrs; all participants had an incomplete SCI; C4-T12 lesion level; 2-10 yrs post-injury.
Treatment: 12-months of FES to quadriceps for strengthening and gait (specific program not specified). Additional stimulation to hip abductors and erector spinae as needed.
Outcome Measures: walking speed with FES compared to orthosis.
  1. No significant difference in gait speed with FES compared to ambulation with orthosis.
  2. Participants were able to use FES for 10-45 minutes.
  3. All participants were able to use FES at home for standing and walking; 2 also use FES for outdoor walking.
  4. 3 patients eventually discontinued use of FES citing impracticality for regular use.


To date, there are no randomized controlled or blinded assessments of the training effects of FES to improve mobility after SCI. Furthermore, only three of the studies reviewed here (Thrasher et al. 2006Granat et al. 1993Klose et al. 1997) report specific usage parameters for FES during gait rehabilitation, whereby FES was applied for at least 30 minutes, 2 to 5 times/week for up to 4.5 months. In the remainder of the studies, participants were provided with FES systems to use at home “as much as possible” or “as desired” over the course of the study (Ladouceur and Barbeau 2000a2000bWieler et al. 1999Stein et al. 1993). Results from the ten pre-post studies included here show that almost all the participants showed improvements in gait parameters (walking speed or distance) when FES was used (Thrasher et al. 2006; Ladouceur and Barbeau 2000a2000b; Wieler et al. 1999Klose et al. 1997Granat et al. 1993Stein et al. 1993Granat et al. 1992). This is not surprising, given that the FES could compensate for weakened or paralyzed muscle function during gait. Of greater interest is the finding of carryover effects after FES training. Several investigators have also reported a carryover effect after FES training such that improvements in functional ambulation (e.g. overground walking speed and distance, step length) persisted even when the stimulator was turned off (Ladouceur and Barbeau 2000bWieler et al. 1999). This suggests that neuroplastic changes may have taken place in response to regular use of FES during walking. Indeed, it has been shown in non-disabled human participants that the combination of treadmill walking and FES led to an acute increase in corticospinal excitability that persists even after the cessation of FES (Kido Thompson and Stein 2004). Improved muscle strength and conditioning after regular use of FES could also contribute to carryover effects in walking function (Granat et al. 1993). The use of FES and weight-bearing also helps to maintain the subtalar and midfoot joint mobility needed for walking (Bittar & Cliquet 2010).

Although laboratory studies advocate the efficacy of FES systems for improving ambulatory function in patients with SCI, the effectiveness of any technology is only as good as its acceptance by the intended users. Wieler et al. (1999) reported that the majority of their participants found they could use the FES device easily on a regular basis and that they walked better with the FES. Those who reported difficulties reported problems with finding the proper stimulation site or technical difficulties with the leads, switches, or electrodes. There have also been reports of musculoskeletal complications such as ankle sprain, calcaneum fracture, back pain, or falls with FES use (Brissot et al. 2000Gallien et al. 1995). Some of these complications may have been associated with commencement of upright exercise (gait) after a period of being non-ambulatory. Anecdotal reports found in several studies suggest that most participants mainly use FES indoors or at home, for short distance walking, to prevent complications due to prolonged immobilization, and to enhance physical fitness rather than functional community ambulation (Brissot et al. 2000Gallien et al. 1995Klose et al. 1997). Participants who do use FES outdoors for community ambulation tend to be those less severely impaired (Brissot et al. 2000Granat et al. 1993).

The functional benefits derived from FES are also quite variable. For instance, Stein et al. (1993) report that most participants showed a modest improvement in gait speed (average: 4 m/min), which was more significant for the more severely disabled participants. Higher-functioning participants felt that this small benefit in gait speed did not warrant the daily use of FES. In contrast, Ladouceur and Barbeau (2000b) reported that there was a tendency for the participants with initially faster gait speed to have greater absolute improvements. Thus, outcomes from FES-use also seem to be quite variable in terms of walking speed (Ladouceur and Barbeau 2000bStein et al. 1993) or distance (Klose et al. 1997).


There is level 4 evidence (Thrasher et al. 2006; Ladouceur and Barbeau 2000a2000bWieler et al. 1999Klose et al. 1997Granat et al. 1993Stein et al. 1993Granat et al. 1992) that FES-assisted walking can enhance walking speed and distance in complete and incomplete SCI.

There is level 4 evidence from 2 independent laboratories (Ladouceur and Barbeau 2000a,bWieler et al. 1999) that regular use of FES in gait training or activities of daily living leads to persistent improvement in walking function that is observed even when the stimulator is not in use.