Electrical and Magnetic Stimulation

After upper motor neuron SCI, bowel reflex centres within the sacral spinal cord may be released from descending inhibition, and may be influenced by somatic input (Frost et al. 1993). A number of studies have shown that electrical or magnetic stimulation of the somatic nervous system can bring about an alteration in visceral function in humans. For example, Riedy et al. (2000) showed that short periods of electrical stimulation with perianal electrodes resulted in an increase in anal pressures.

The sacral anterior root stimulator (SARS) employs electrodes implanted onto the second, third and fourth sacral anterior nerve roots to deliver short bursts of high voltage stimulation several times daily resulting in increased colonic activity, reduced constipation and sometimes defaecation during the stimulation.

A significant number of electrical or magnetic stimulation methods have been proposed and tested for their ability to improve bowel function in individuals with upper motor neuron SCI. These techniques are varied, from the relatively inexpensive and non-invasive abdominal muscle stimulation belt (Korsten et al. 2004) and percutaneous peripheral nerve stimulation (Mentes et al. 2007), to more complex and invasive techniques including implantation of epineural electrodes (Davis et al. 2001) and epidural or anterior sacral root electrodes (Kachourbos & Creasey 2000Chia et al. 1996Binnie et al. 1991MacDonagh et al. 1990) for functional electrical stimulation. Magnetic stimulation techniques have also been also used; a magnetic field is generated in order to induce an electric field, which then generates sufficient current to stimulate the peripheral nerves (Lin et al. 2002).

Sun et al. (1995) investigated the role of spinal reflexes in anorectal function. Their subjects (C6-T12 traumatic SCI) underwent anorectal manometry and electromyography before and after having a sacral posterior rhizotomy performed by the same neurosurgeon. They found that all subjects lost conscious control of the external anal sphincter as well as responses to intra-abdominal pressure and rectal distention (EAS electromyographic activity, increase in anal pressure), demonstrating the significant role of spinal reflexes.

A review paper on low amplitude chronic electrical stimulation of the sacral plexus (Kenefick & Christiansen 2004), has been reported to reduce fecal incontinence and constipation in selected patients with incomplete SCI. Magnetic stimulation may produce similar results and is noninvasive. Morren et al. (2001) studied the effects of magnetic sacral root stimulation on anorectal pressure and volume in individuals with fecal incontinence and in patients with SCI. They found that magnetic sacral root stimulation produces an increase in anal and rectal pressure and a decrease in rectal volume in healthy subjects and patients with fecal incontinence or a spinal cord injury.


A variety of methods using electrical or magnetic stimulation devices have been tested to determine whether or not they can improve bowel management outcomes in individuals with SCI.

The use of functional magnetic stimulation decreased mean colonic transit time (Tsai et al. 2009Lin et al. 2002Lin et al. 2001), as did stimulation of the abdominal muscles (Hascakova-Bartova et al. 2008Korsten et al. 2004). While preliminary results for posterior tibial nerve stimulation in individuals with SCI appear promising, it is important to note that the statistical significance of the improvements in clinical and physiological parameters were not reported and the study involved only two participants (Mentes et al. 2007).

In terms of implanted electrical stimulation systems, Binnie et al. (1991) found that an implanted Brindley (sacral anterior root) stimulator did not reduce oro-caecal time for individuals with SCI, however, subjects in the stimulator group did experience a significant increase in defecation compared to the control SCI group (Binnie et al. 1991).

Subsequent studies using sacral anterior root stimulation yielded improvements in bowel function, including better spontaneous evacuation (Lombardie et al. 2011Sievert et al. 2010Chia et al. 1996), reduced bowel program times (Kachourbos & Creasey 2000Vallès et al. 2009Lombardi et al. 2009), elimination of autonomic dysreflexia related to bowel management (Kachourbos & Creasey 2000), elimination of manual help for defecation (Macdonagh et al. 1990). Both Holzer et al. (2007), and increased quality of life (Sievert et al. 2010Lombardi et al. 2011Lombardi et al. 2009Holzer et al. 2007Kachourbos & Creasey 2000). Jarrett et al. (2005) found reduced number of incontinence episodes through the use of sacral nerve stimulation, but conflicting evidence on the effects on resting and squeeze anal canal pressures (Lombardi et al, 2011Holzer et al. 2007Jarrett et al. 2005). Gstaltner et al. (2008) found that sacral nerve stimulation improved fecal continence, quality of life, and deliberate retention of faeces in their study among subjects with cauda equine syndrome. Finally, the Praxis FES system increased the frequency of defecation and decreased the time required for bowel evacuation in one subject (Johnston et al. 2005).

Worsøe et al.’s (2013) review of nerve stimulation techniques in neurogenic bowel dysfunction viewed neurostimulation as a way of ‘re-establishing neurogenic control and alleviating symptoms’.They reported that the sacral anterior root stimulator improves bowel function in some patients with complete SCI while sacral nerve stimulation can improve function in selected patients with a variety of incomplete neurologic lesions. They also suggest that peripheral stimulation using electrical stimulation or magnetic stimulation may offer non-invasive treatment alternatives for neurogenic bowels. However, they concluded that due to the lack of research evidence required to support informed choice, the latter techniques should be reserved for research at present.


There is level 1b evidence (from one RCT: Korsten et al. 2004) that electrical stimulation of the abdominal wall muscles can improve bowel management for individuals with tetraplegia.

There is level 2 evidence (from one prospective controlled trial: Binnie et al. 1991) that supports the use of sacral anterior root stimulation to reduce severe constipation in complete SCI.

There is level 4 evidence (from three pre-post studies: Tsai et al. 2009, Lin et al. 20012002) that functional magnetic stimulation may reduce colonic transit time in individuals with SCI.

There is level 4 evidence (from one pre-post study with two subjects: Mentes et al. 2007) that posterior tibial nerve stimulation improves bowel management for those with incomplete SCI.

There is level 4 evidence (from one pre-post study with two subjects: Johnston et al. 2005) that the Praxis FES system increases the frequency of defecation and decreases time required for bowel care in individuals with SCI.

Authors; Country

Date included in the review

Total Sample Size

Types of Articles




Level of Evidence

Worsoe et al. 2013;


Systematically reviewed articles from databases listed to the right (dates searched not listed)

Number of studies not listed

Level of evidence: methodological quality not assessed

Type of study:

No RCTs, all lower-level studies


Method: Systematic literature search of neurogenic bowel disorder in patients with SCI treated by sacral anterior root stimulation (SARS), sacral nerve stimulation (SNS), peripheral nerve stimulation, magnetic stimulation and nerve rerouting.

Databases: PubMed, Embase, Scopus, Cochrane Library

  1. SARS improves bowel function in some patients with complete SCI.
  2. Nerve re-routing is claimed to facilitate defecation through mechanical stimulation of dermatomes in patients with complete or incomplete SCI or myelomeningocele.
  3. SNS can reduce NBD in selected patients with a variety of incomplete neurologic lesions.
  4. Peripheral stimulation using electrical stimulation or magnetic stimulation may present non-invasive alternative
Author Year; Country


Research Design

Total Sample Size





Korsten et al. 2004;


PEDro = 6



Population: 8 male participants (6 tetraplegia; 2 paraplegia); age mean(SD): 48(14)yrs; duration of injury mean(SD):13(8)yrs.

Treatment: An abdominal belt with embedded electrodes was wrapped around at the umbilicus level and was used in conjunction with the subject’s regular bowel care but activation of the device was randomized. Participants used the belt for six bowel care sessions over 2 weeks (the belt was activated for three sessions and deactivated for three sessions).

Outcome Measures: Time to first stool, time for total bowel care.

  1. Time to first stool and time for total bowel care were significantly shortened in the 6 participants with tetraplegia, but not in the 2 participants with paraplegia.
Worsoe et al. 2012;




Level 4

Population: Participants with supraconal SCI (6M, 1F); Age: median (range) age: 50 (39-67); median (range) DOI: 19 (12-33).

Treatment: Dorsal genital nerve (DGN) stimulation using an amplitude of twice the genito-anal reflex threshold. A pressure controlled phasic rectal distension protocol was repeated 4 times with participants randomized to stimulation during 1st and 3rd distension series or 2nd and 4th distension series.

Outcome Measures: Rectal cross sectional area (CSA) and rectal pressure

  1. Median rectal CSA was smaller with than without stimulation in all patients at 20cmH2O distension pressure (median decrease of 9%) and in 6/7 patients at 30cmH­2O distension pressure (median decrease 4%) above resting rectal pressure.
  2. Rectal pressure-CSA relation was significantly reduced during stimulation at 20cmH2O and 30cmH2O distension.
Tsai et al. 2009;



N = 22

Population: 22 chronic SCI participants with intractable neurogenic bowel dysfunction (19M, 3F), mean age 46.7 yrs, range 22–65yrs); divided into group 1 (supraconal lesion, N=15) and group 2 (incomplete conal/caudal lesion, N=7)

Treatment: subject underwent a

3-week stimulation period, consisting of 20-min stimulation sessions twice a day. Each session contained 10 min of thoracic nerve stimulation with the centre of the coil placed at the T9 spinal process, and another 10 min of lumbosacral nerve stimulation with the coil at the L3 spinal process. Participants underwent stimulation from a sitting position. The stimulation intensities were set at 50% on the first day, 60% on the second day, and then stabilized at 70% for the remaining days. The stimulation frequency, burst length, and interburst intervals were fixed at 20 Hz, 2 sec, and 28 sec, respectively.

Outcome Measures: Colonic transit times; Knowles-Eccersley-Scott Symptom Questionnaire (KESS, evaluates frequency of bowel movement using existing therapy, difficulty of evacuation, laxative use, and time taken for bowel evacuation)

  1. Mean colonic transit times decreased from 62.6 hrs to 50.4 hrs
  2. Frequency of laxative use, unsuccessful evacuation attempts, feeling of incomplete defecation, difficulty with evacuation, and time taken to evacuate significantly decreased
  3. Mean scores on the KESS significantly decreased from 24.5 to 19.2 points, indicating a significant overall improvement in bowel symptoms.
Hascakova-Bartova et al.



Prospective Controlled Trial

N = 10

Population: 7 participants in the electrical stimulation group (ESG) with level of injury ≥ T10 and complete paralysis of abdominal muscles (6M 1F; mean (SD) age: 42(19) yrs). 3 additional participants (all male, ages 25, 43, 63) were in the placebo group (PG).

Treatment: Surface abdominal neuromuscular electrical stimulation. administered 25 min/day, 5 days/wk, for 8 wks

Outcome Measures: colonic transit measured by radiopaque markers

  1. Accelerated colonic transit (ascending, transverse and descending colon) in all participants who received treatment. The ESG group had a significant decrease in % of number of markers in the ascending, transverse and descending colon after the NMES treatment (8.86 +/- 8.65% markers before NMES vs. 4.57 +/- 5.99% after NMES).
  2. No significant changes in the colonic transit for PG (% number of markers in the A+T+D colon: before NMES = 9.17 +/- 5.91 vs. 9.17 +/- 5.04).
Mentes et al. 2007




Population: A 51-year-old woman who had undergone discectomy for lumbar disc herniation 3 years ago and a 31-year-old man with a 10-year history of lumbar cavernous haemangioma.

Treatment: Posterior tibial nerve stimulation was performed for 30 min, every other day for 4 weeks, and was then repeated every 2 months for 3 times.

Outcome Measures: Rectal sensory threshold, Wexner fecal incontinence score, fecal incontinence severity index, fecal incontinence quality of life scales, resting pressure, and maximum squeeze pressure measurements.

  1. Both patients showed improvements in Wexner fecal incontinence score, fecal incontinence quality of life scales, clinical parameters and physiological measurements. Significance of improvements not reported in this study.
Lin et al. 2002;




Population: 4 participants with SCI between C3-C7, AIS class: 3 B,1 D;

5 controls, mean (SD) age: 42(5.8) yrs

Treatment: Each subject participated in a 3-day protocol; day 1: baseline gastric emptying study, day 2: no change in the eating pattern and no intervention,day 3: participants received functional magnetic stimulation (FMS) while undergoing a second gastric emptying study.

Outcome Measure: Rate of gastric emptying and time to reach gastric emptying half time (GEt1/2­

  1. Gastric emptying time post-stimulation was significantly shorter than the baseline for both AB and SCI groups. Mean (SE) GE t1/2 for the groups were: AB: baseline= 36(2.9); post- stim=33(3.1) SCI: baseline=84(11.1); post-stim=59(12.7)2.   There was significantly more gastric emptying at 30, 60, 90 and 120 min after FMS than at baseline. For the SCI group, % of gastric emptying at 30, 60, 90 and 120 min were: – baseline: 6(2.9); 16(7.6); 38(5.2); 55(6.7) – post-stim: 26(8); 49(10.2); 61(9); 69(8.6)
Lin et al. 2001;




Population: 13 SCI, 2 able-bodied controls; Level of injury: C3-L1; Duration of injury 11-35 yrs (protocol 2 only); AIS classes: 7 A, 3 B, 1 C.

Treatment: FMS was delivered via a magnetic coil placed on the trans-abdominal (suprapubic region while subject lay supine) and lumbosacral (L3-L4 along midline) regions. Protocol 1: measured the immediate effects of FMS on rectal pressure Protocol 2: measured the effects of FMS on total and segmental colonic transit times after a 5-week stimulation period (20 min sessions twice a day). Outcomes were collected before and after the 5-wk stimulation program.

Outcome Measures: rectal pressure, total and segmental colonic transit times

  1. Rectal pressures increased with sacrolumbar stimulation, and with transabdominal stimulation.
  2. After protocol 2, the mean (SD) colonic transit times decreased from 105.2(6.66) to 89.4(6.94) hours.
Author Year; Country


Research Design

Total Sample Size

Methods Outcome
Rasmussen et al 2015a




Population: N=277 (145M, 132F)

Median (range) age 49 (19-80)

Median (range) time from SCI to SARS surgery 10 (0-49) years

Median (range) time from SARS surgery to follow-up 13 (1-25) years

AIS-A/B/C: 234/38/5

131 cervical, 143 thoracic, 3 lumbar

Treatment: SARS implantation

Outcome Measures: 1-10 visual analog scale (VAS) questionnaire on SARS satisfaction and bowel dysfunction, NBD score, St. Marks fecal incontinence score, Cleveland constipation score

1.      Median (range) overall satisfaction with SARS 10 (0-10)

2.      Significant changes before and after SARS in median (range) of:

Overall severity of bowel symptoms:

6 (4-8) to 4 (2-6)

NBD score:

17 (11-21) to 11 (9-15)

St. Marks score:

4 (0-7) to 4 (0-5)

Cleveland score:

7 (6-10) to 6 (4-8)

3.      Lower total dependence on assistance, use of suppositories, digital evacuation, and mini enemas after SARS

Chen & Liao 2015


Retrospective case series



N=23 (17M, 6F) with spinal cord injury or disease underwent SNM testing (7-28 days):

Mean (SD) age 37.3 (2.9)

Mean (SD) time since onset 15.5 (3.6) years

9 SCI, 9 myelomeningocele

2 complete, 21 incomplete

N=13 (10M, 3F) of which underwent permanent SNM implantation:

Mean (SD) age 34.1 (3.2)

Mean (SD) time since onset 14.4 (4.8) years

Treatment: Sacral neuromodulation (SNM)

Outcome measures: Constipation (Wexner score) and bladder measures

1.    75.0% rate of improvement for constipation during testing

2.    After implantation, 12/13 experienced improvement in constipation; 11 of which experienced ≥50% improvement

3.    Loss of effect on constipation in 1 patient at 3 months post implantation

4.    Significant reduction in Wexner score (for those with urinary incontinence; N=9) from baseline to testing phase and from baseline to follow-up (17.5±2.0 months after implantation) stage

Lombardi et al. 2011;



N= 75

Population: 75 males with incomplete SCI who received permanent SNM implantation; Age:18-75yrs; year post injury>6 months; suffering from neurogenic bowel symptoms (NBS), neurogenic lower urinary tract symptoms, and/or neurogenic erectile dysfunction refractory to conservative management

Treatment: Sacral neuromodulation implantation (Medtronic, Inc)

Stage 1- electrode inserted percutaneously in third sacral foramina.

Stage 2- Permanent implantable pulse generator implanted in patient’s buttock only if main symptoms improved by at least 50% during phase 1.

Follow-ups scheduled at 1, 3, 6 months post implantation, and subsequently every 6 months

Outcome Measures: SF-36 health survey questionnaire; number of fecal incontinence episodes per week; number of evacuations per week and Wexner score (severity of fecal incontinence)

1.    Mean follow-up period from SNM permanent implantation to final visit was 53 months.

2.    Patients presenting with NBS improved all parameters by at least 50% compared with baseline for mean (SD) number of occurrence of fecal incontinence (4.33 (1.66) vs 1.25 (1.17)); days with pads (4.5 (1.51) vs 1.33 (1.16)) and Wexner scores (13.66 (1.50) vs 5.83 (0.98)) per week at baseline vs final visit.

3.    A significant improvement (20%) in SF-36 scores for all patients compared with baseline.

4.    11 adverse reactions were reported (5 individuals required change in stimulation sensation, 2 experienced loss of efficacy, 1 reported pain per leg spasticity, 2 reported pain at implanted pulse generator site, 1 reported adverse change in bowel function.

Sievert et al. 2010;



N SCI treated with SNM= 10

Population: 16 males with complete traumatic SCI (>T12, AIS A); 10 in treatment group, 6 controls; mean age 31 (range 19-47)

Treatment: Implanted with tined lead electrode/sacral nerve modulator (SNM) at third sacral foramen.

Controls: Prescribed oral antimuscarinics.

Outcome Measures: Participants provided bladder, bowel and erectile function diaries and answered questionnaires including laxative use

1.    SNM group reported they felt there was sufficient SMN colon movement without oral laxatives

2.    SNM group has improved bowel movement control (incontinence events decreased)

3.    All SNM participants reported significantly better quality of life than the controls. The specific SCI questionnaire used was not mentioned and no scores were given.

4.    No intra- or post-operative complications were reported for the implant participants.

Lombardi et al. 2009;



N = 23

Population: 15M 8F; 2 cervical, 9 thoracic, 13 lumbar; mean (SD) age = 36(9) years; 12 participants had constipation (C), 11 had fecal incontinence (FI).

Treatment: sacral neuromodulation – unilateral implantation in the foramen sacral S3 root

Outcome Measures: Wexner questionnaire, SF-36, number of fecal evacuations per week, time per defecation.

1.    Mean time from neurological diagnosis to SNM therapy was 41 months (range 18-96). Mean follow-up time from SNM implantation to final visit was 44.3 months (range 18-96).

2.    Both the constipation and fecal incontinence groups experienced significant improvements in the:
-Wexner score:
C group: pre-SNM=19.91, post-SNM final visit=6.82
FI group: pre-SNM=13.09, post-SMN final visit=4.91
-had increased evacuations per week: C group: pre-SNM=1.65, post-SNM final visit=4.98
– had decreased number of fecal incontinence per week

FI group: pre-SNM=4.55, post-SMN final visit=1.32
– reduced time per defecation:
C group: pre-SNM=45.85, post-SNM final visit=11.67 min.

– had a decreased number of pads used/day fecal incontinence: pre-SNM=2.36, post-SMN final visit=0.95

3.    Both groups had a significant improvement in the mental and general health subscales of the SF-36.

4.    A total of 1038 months yielded 12 adverse events in 5 patients: 4 related to pain at generator site, 3 to spasticity pain in lower limbs, 1 to excessive tingling in vaginal area, and 4 for battery changes.

Valles et al. 2009;



N = 18

Population: 9M 9 F; 4 cervical, 13 thoracic, 1 lumbar; AIS: 14 A, 1 B, 3 C; mean age 39 (range 18-63)yrs,

Treatment: Sacral anterior root stimulator, follow up from 12-21 months post implantation

Outcome Measures: Use of laxatives, number of bowel evacuation methods used, frequency of and time dedicated to bowel movements, prevalence of constipation, Wexner questionnaire

1.    After implantation, fewer patients took laxatives (10 vs. 13) and patients used significantly less methods to evacuate bowel (1.5 vs. 2.1)

2.    The frequency of bowel movements significantly increased (10 vs. 6 participants had bowel movements every day), and time dedicated decreased (11 vs. 9 participants dedicated <30min) but was not significant.

3.    Prevalence of constipation significantly decreased (7 vs. 11); episodes of fecal incontinence increased (18 vs. 16) and the mean Wexner score decreased (4.6 vs. 5.2) but these results were not significant.

Gstaltner et al. 2008;



N = 11

Population: Cauda equine syndrome with flaccid paresis of the anal sphincter muscle and fecal incontinence

Treatment: Participants underwent percutaneous nerve evaluation (PNE); following this analysis, a period of external temporary sacral nerve stimulation was performed in the both sides of the S2 or S3, and if the patient showed improvements in outcome measures, a permanent stimulator was implanted (N=5)

Outcome Measures: Wexner questionnaire, participants’ subjective perceptions of quality of life determined through interview.

1.    Improved fecal continence in all 5 participants (median score of Wexner score decreased from pre-SNS (15 (9-19)) to post-SNS (5(2-9)).

2.    Reported perianal sensitivity and deliberate retention of feces improved in all 5 participants.

3.    Reported improved quality of life in all 5 participants.

4.    One complication was reported – one patient had minimal leakage of cerebrospinal fluid following the PNE, after removal of the needle, no further symptoms were reported.

Holzer et al. 2007;



N = 36

Population: 17 participants with SCI from spinal cord surgery, 11 from spinal cord trauma, 4 from meningomyelocele; 14M 22F; median age 49 (range 10-79) yrs.

Treatment: Sacral nerve stimulation in the sacral foramina S2-S4; follow up after 12 and 24 months for those who underwent permanent implantation after initial evaluation (N=29)

Outcome Measures: Number of incontinence episodes, maximum resting and squeeze anal canal pressure, American Society of Colorectal Surgeons (ASCRS) Quality of Life questionnaire

1.    Median number of incontinence episodes decreased from 7 (range 4-15) to 2 (range 0-5) in 21 days

2.    There were statistically significant improvements in maximum resting and squeeze anal pressure after 12 and 24 months.

3.    There was significant improvement in the ASCRS Quality of Life questionnaire for participants who underwent permanent implantation

Jarrett et al. 2005;



N = 12

Population: 6 participants with SCI from disc prolapse, 4 from trauma, and 1 from spinal stenosis; 4M 9F; median age 58yrs (range 39-73). Exclusion criteria: paraplegia.

Treatment: Temporary sacral nerve stimulation, permanent implant if subject demonstrated positive results, median follow up is 12 months (range 6-24)

Outcome Measures: Frequency of incontinence; resting and squeeze anal canal pressure ASCRS QoL questionnaire; SF-36 quality of life questionnaire

1.    12 participants demonstrated positive results and underwent permanent implantation

2.    Mean (SD) frequency of incontinence decreased from 9.33 (7.64) episodes per week at baseline to 2.39 (3.69) at last follow up

3.    ASCRS QoL coping score significantly improved; the SF-36 QoL scores did not change

4.    Neither resting nor squeeze anal canal pressure changed significantly compared to baseline

Johnston et al. 2005;



N=3 (2 had neurogenic bowel outcome measures, results presented for 1)

Population: Age: 17-21yrs; all with motor-complete thoracic SCI (T3-T8) of 1-1.5 years duration.

Treatment: All participants received implantation of epineural electrodes for skeletal muscle stimulation for upright mobility. 2 participants also received additional extradural electrodes (S2,3,4) for bowel and bladder management. Stimulation was conducted via 22 channel implanted Praxis FES system.

Outcome Measures: Rectum and anal sphincter local pressures, patient self-report diary wherein he described the quantity of stool passed during each daily session, the time spent, and a numerical ‘satisfaction’ rating from 1 (least satisfied) to 10 (most satisfied)

1.    Low-frequency electrical stimulation (20 Hz, 350 μs, 8mA) at S3 increased anal sphincter and rectal pressure

2.    Over a 2-month period, daily use of electrical stimulation appeared to provide a significant improvement in bowel management, causing an increased frequency of defecation, a decrease in time required for bowel evacuation (from 52 min to 23 min), and improved satisfaction over non-stimulation evacuation methods. 2 stimulation strategies were used by the patients: 1) low-freq stim. for 30s on, 30s off for 5-10 min; 2) 5-10 min of low-freq. stim followed by 5 min of low/high freq. combination stim.

Kachourbos & Creasey 2000;



N= 16

Population: Adults with SCI (demographics not reported) and a history of bowel complications

Treatment: Implantation of sacral roots electrodes (S1-S3) with rhizotomy at the conus medularis. Stimulation was delivered via use of VOCARE Bladder and Bowel Control System (Finetech-Brindley stimulator).

Outcome Measures: Bowel program times; occurrence of autonomic dysreflexia due to bowel movement; quality of life regarding dependence, socialization, sense of control, and overall quality of life

1.    Bowel program times were reduced from a mean of 5.4 hours per week pre-operatively to 2.0 hours per week post-operatively.

2.    Autonomic dysreflexia due to bowel movements was eliminated.

3.    Users reported a greater sense of independence, increased socialization, greater control over their lives, improved self-image, decreased feelings of depression, improved interpersonal relationships and an overall improvement in quality of life.

Chia et al. 1996;




Population: Level of injury: 4 C4-C6, 4 T3-T11; 6M: 2F; Age: mean 40, range 20-53yrs. All participants suffered from severe constipation (≤2 bowel movements/week and/or straining at stool for >25% of the time)

Treatment: Anterior sacral roots electrodes (S2,3,4) implanted for electrical stimulation.

Outcome Measures: Bowel frequency, laxative use, suppository use, need for digital evacuation, anorectal monometry

1.    6/8 patients had improvement in bowel function: 4/6 were able to evacuate spontaneously after stimulation, 1 described digital evacuation as “easier,” 1 used an occasional suppository without the need to digitally evacuate.

2.    Six participants with improved bowel routine also showed increased rectoanal pressure immediately after stimulation.

Binnie et al. 1991;


Prospective Controlled Trial


Population: 3 groups:
1) a control group of 10 healthy volunteers (8M 2F; mean age: 29.1)
2) 10 SCI participants without the Brindley implant (9M 1F; C4-T10; mean age: 34.1; mean DOI: 8.1 yrs)
3) 7 SCI participants with implanted Brindley implant (6M 1F; C5-T3; mean age: 36.3; mean DOI: 7.4 yrs; mean time since implant: 2.6 yrs)Treatment Brindley anterior sacral root stimulator implantOutcome Measures: Oro-caecal and oro-anal transit time, fecal water content, and frequency of defecation
1.    There was no significant difference in mean (SEM) oro-caecal times between the AB group (2.95 (0.15) hrs) and the SCI group (3.4 (0.34) hrs) or between the AB group and the Brindley stimulator group (3.4 (0.34)).

2.    Paraplegics in stimulator group (0.78 (SEM=0.08) days) had a significant increase in defecation frequency compared to the SCI control group (0.37 (0.07)).

3.    There was a non-significant trend towards a more rapid CTT in the stimulator group compared to the SCI group.

MacDonagh et al. 1990;




Population: Complete supraconal spinal cord lesions, 9M 3F, mean age: 33 (range: 21-49), 10 thoracic, 2 cervical, > 2 years post-injury

Treatment: Brindley-Finetech intradural sacral anterior root stimulator implant

Outcome Measures: full defecation

1.    6 patients achieved full defecation with implant and manual help was no longer required.

2.    Time taken to complete defecation was reduced.

3.    All were free from constipation.