Intrathecal Baclofen Pump and Sacral Root Stimulation

An intrathecal baclofen pump is a device for treatment of severe spasticity. This medical device is placed under the skin during a surgery (generally under abdominal skin) and is used to deliver baclofen directly into the intrathecal space surrounding the spinal cord. Baclofen stimulates GABA-B receptros and acts as a skeletal muscle relaxant.

For sacral anterior root stimulation (SARS) implantation, a laminectomy is performed between S2-L4 to expose the sacral nerve roots of S2-S4 and possibly S5 (Worsoe et al. 2013). Anterior and posterior nerve roots are distinguished using intraoperative stimulation (Worsoe et al. 2013; Creasey et al. 2001). Then the sleeved electrodes are placed bilaterally along the S2-4 anterior roots and sutured onto the target nerves (Creasey et al. 2001). Meanwhile, the S2-5 posterior root nerves are sacrificed through a bilateral rhizotomy. This procedure enables urinary continence during stimulation, maintenance of bladder capacity, and reduces the risk of AD by abolishing the reflex arcs mediated by these nerves (Valles et al. 2009; Creasey et al. 2000). The electrode cables are then subcutaneously tunneled between the costal margin and iliac crest and connected to a subcutaneous transmitter box in the anterior abdominal wall (Creasey et al. 2001). The transmitter box and subsequently the stimulation can be activated by the patient using a wireless receiver block.

Author Year; Country
Research Design
Total Sample Size
Methods Outcome
Lombardi et al. 2008
Prospective Comparison trial
Level 2
Population: 54 males with SCI (mean age
42.8) suffering from Lower Urinary Tract
Symptoms (LUTS) and concomitant erectile
Group A – 30 neurogenic patients, (mean
age 41.3; range 27–69), all showing at least
partial peripheral or central preservation of
the upper motor neuron. 6 had incomplete
SCI, 3 had myelitis, 1 had MS, 2 had disk
herniation, and 2 had peripheral
Group B consisted of 24 idiopathic patients
(mean age 44.6; range 27–62).
To evaluate if sacral neuromodulation
(SNM) using the InterStim system improves
erectile function. Stimulation consisted of
continuous pulses with a frequency of 20
Outcome Measures:
the five-item version of the International
Index of Erectile Function (IIEF-5)
A score of IIEF-5 equal to or higher than
25% compared to baseline indicated
remarkable clinical enhancement. Three
months after permanent implantation, the
IIEF-5 was completed again. Those who
benefited significantly in erectile function
completed the IIEF-5 semiannually. A final
checkup was performed in July 2007.
1. In the first post-SNM visit, there was a
significant improvement in the median
IIEF-5 score of group A (Neurogenics)
(from 14.6 (range 11–18) to 18 (range
12–23) using the Wilcoxon test (P<0.02).
2. The patients’ history revealed that
erectile impairment was concomitant to
LUTS (Fisher test P=0.008) in 12
neurogenic subjects compared to two
idiopathic subjects.
3. Overall, 22 out of 52 males (42.3%)
showed erectile impairment according to
the IIEF-5. More precisely, 14 out of the
29 neurogenic patients (48.2%) and 8
out of the 23 idiophatic patients (34.7%)
showed erectile impairment.
Lombardi et al. 2008
Prospective Comparison trial
Level 2
31 women, 17 of whom had neurogenic
bladder dysfunction with permanent SNM
Group A comprised 18 neurogenic
individuals, with mean age of 37.4 years
(range 23–48). All of them showed at least
partial peripheral or central preservation of
the upper motoneuron confirmed with
appropriate neurophysiologic investigations.
Group B comprised 15 idiopathic females,
with mean age of 37.4 years (range 25–46).
All neurological diseases were excluded in
these subjects using appropriate
neurophysiologic tests such as anal
sphincter electromyography.
To evaluate if SNM improves sexual
function in females treated with SNM for
lower urinary tract dysfunction.
Outcome Measures: Improvement in blood
sexual function as measured by the Female
Sexual Function Index (FSFI) and the
Female Sexual Distress Score (FSDS).
1. Four out of 11 participants showed
clinically significant improvement in
sexual health (an increase of 60% of the
total score or of one FSFI domain, or
50% improvement on the FSDS).
2. Mean duration of sexual improvement
was 23 months.
3. The positive effects regarding sexuality
may be due either to enhancement of
LUTS or to the direct stimulation of the
sacral roots (S3).
Sievert et al. 2010
Case control
Level 3
Population: N: 16
Level: all thoracic; all complete; all AIS
Score A
Etiology: traumatic
Experimental Group
N: 10
Age: Mean 30.5 years, Range 19-38 years
Control Group –
N: 6
Age: Mean 36.5 years, Range 27-47 years
Treatment: Sacroneuromodulation
Stimulation (SNS) (Interstim- I & II)
bilaterally implanted at the third sacral
foramen. Control group was people with SCI
given an antimuscarinic medication
prescription with no stimulation. Follow-up
schedule: 3 and 6 months, then every 6
months thereafter.
Outcome Measures: bowel movement
details (participant diaries), laxative use,
and QOL questionnaire
1. The group with Sacral Neuromodulators
(experimental group) reported sufficient
colon movement without oral laxatives
2. People in the Stimulation group reported
higher QoL than the controls: more
independent and “normal social
3. With additional Interstim- II
programming, two patients experienced
improved erectile function that
permitted satisfying sexual intercourse.
Calabrò et al. 2014
Level 4
Population: 20 men (mean age
34.85±10.27 years) affected by severe
spasticity due to SCI (10), vascular (3),
degenerative (6) and congenital (1)d origins;
level of lesion C4 – T10 with a mean disease
duration of 6.1±4.45 years
Treatment: Implantation of a Synchromed
pump with port and a drug administration
device (DAD) with a 20mL reservoir.
Intrathecal baclofen was administered
through the pump and port system (mean
dose of 75±25 mg/day).
Outcome Measures: All patients
underwent neurological and sexological
tests using the International Index of
Erectile Function (IIEF) and the Diagnostic
Impotence Questionnaire (DIQ) before
pump implantation and approximately 2
months after implantation. All participants
underwent specific clinical scales to
evaluate force, muscle tone, cognition and
mood, and specific sexual questionnaires,
including a semi-structured interview.
1. Decrease in the IIEF median scores
before and after implantation.
2. Spasticity, spasms, and patient’s
perception of their own quality of life
(QoL) improved after ITB administration
but with a worsening of sexual
3. Found a correlation between ITB
dosage and IIEF scores (ρ=-0.60; P <
4. Before implantation, 55% of
participants declared difficulties to
achieve or maintain an erection,
whereas after the pump implant 80% of
the sample suffered from erectile
Lombardi et al. 2011
Level 4
Population: N: 75 men (8 completed NBS
Level: incomplete
Duration: > 6 months
Treatment: using sacral neuromodulation
(SNM) implanted at third sacral foramen.
and comparing: before (14 day baseline) vs.
after implantation .
Follow-ups after: 1, 3, and 6 months then
every 6 months after that.
Outcomes: SF-36 QoL questionnaire,
frequency of incontinence, frequency of
evacuations, duration of evacuations,
Wexner fecal incontinence and constipation
questionnaires, pad usage, anorectal
manometry and International Index of
Erectile Function (IIEFS; male sexual
function questionnaire).
1. Individuals (6) with neurogenic erectile
dysfunction had a 37.4% improvement
in IIEFS score and engaged in sexual
intercourse without needing oral
phosphodiesterase 5 inhibitor.
Jones et al. 2008;
Level 4
Population: 7 men with SCI (mean age
36.7 yrs) with positive bulbocavernous
reflex and reported history of sexual activity
since injury.
Treatment: Implantation of intrathecal
baclofen pump.
Outcome Measures: Brief Sexual
Function Inventory (BFSI) questionnaire;
perception of spasticity questionnaire,
developed by Schwartz et al.; SF-36
Health Survey.
1. Generally unchanged rating of
perceived sexual functioning, sexual
relationships, and ejaculation postimplant.
2. Modest to drastic improvements in the
participants’ perception of problems
with sexual functioning.
3. In 3 participants, there was a
relationship between baclofen dosage
and perceived sexual function; as
baclofen dosage increased, BFSI
scores related to erections deteriorated.
4. Significant improvement in the
spasticity scores from pre- to postimplant.
5. Improved health status score in all but
1 subject.
Denys et al. 1998
Level 4
Population: 3 female and 14 male
Time between injury and operation ranged
from 1 to 15 years. All had a complete
lesion of the spinal cord: in 16 cases
situated between T1 and T10; in one patient
at C5.
Treatment: Implantation of intrathecal
baclofen pump (average dose of 290(68.3)
Outcome Measures: yes or no questions
(ability to sustain reflexive & psychogenic
erections, obtain ejaculation without
electrical, vibratory, pharmacologic
stimulation); visual analog scale for penile
rigidity; recall of maximal duration of stable
erection (minutes); modification of libido.
1. Ability to sustain erections was not
affected by treatment.
2. 3/5 participants reported decreased
rigidity after treatment.
3. 4/5 participants reported decreased
erection duration after treatment while 1
subject reported increased duration
after treatment.
4. One subject who had the ability to
obtain ejaculation without electrical,
vibratory or pharmological stim before
treatment was no longer able after
treatment. This ability returned after
baclofen withdrawal.
Van der Aa et al. 1995
Level 4
Population: 5 men with SCI (mean age
35.8 yrs); all participants with sacral reflexes
and reflexive bladder.
Treatment: Implantation of the Finetech-Brindley bladder controller (Sacral anterior
Outcome Measures: Four days after
surgery, bladder capacity, continence, and
sexual function were measured.
1. A sustained full erection can be
achieved in all our male patients using
continuous stimulation; in 12 patients by
stimulation of the $2 anterior roots; in 2
patients by stimulating the $3 anterior
roots. There is no interference with
bladder emptying.


Implantation of a Sacral Anterior Root Stimulator (Brindley et al. 1982) for bladder control usually entails rhizotomy of posterior sacral roots to improve bladder capacity and compliance and reduce reflex incontinence and possibly sphincter spasticity, but in so doing has the disadvantage in men with SCI of abolishing reflex erection, and ejaculation when present. While not the primary indication for implantation, continuous stimulation of S2 or S3 anterior roots has been shown to achieve a sustained and full erection in all of a series of 14 men with complete SCI lesions between C5 –T10 level (van der Aa et al. 1995). Vignes et al. (2001) reported that 60 percent of men with complete SCI were able to achieve an erection by continuous stimulation of S2 roots.

We found 3 studies (Lombardi et al. 2008; Lombardi et al. 2011; Sievert et al. 2010) that used Sacroneuromodulation Stimulation (SNS) in an effort to correct lower urinary tract dysfunction and that also measured sexual function. Proportions of participants in each study recovered erectile function and/or genital arousal; though more research with larger sample sizes are needed.

Concerns have been raised about the impact of intrathecal baclofen (a drug to control spasticity) on sexual function among men with SCI. Baclofen may have an effect on sexual function presumably secondary to the inhibition of visceral afferent input to the lumbosacral spinal cord (Steers et al. 1992). Jones et al. (2008) reported that although there was minimal impact on sexual function after baclofen pump implantation, there was a possible dose response between baclofen and sexual function (i.e. higher the dose to control spasticity, poorer the erection function). Four out of seven subjects noted a decrease in perceived sexual function following an increase in baclofen dosages, although some were utilizing PDE5i as well, and one subject reported a dramatic improvement in rating of sexual function with increase and later tapering in baclofen dose. Denys et al. (1998) reported similar inconsistent findings leading the authors to conclude that the effects of baclofen on sexual function seem to be transitory and reversible with withdrawal or reduction in dose. More recently, Calabro et al. (2014) found that before implantation, 55% of participants declared difficulties to achieve or maintain an erection, whereas after the pump implant 80% of the sample suffered from erectile dysfunction.


There is level 2 evidence (Lombardi et al. 2008) that Sacral neuromodulator stimulation can improve erectile function while simultaneously improving lower urinary tract dysfunction.

There is level 4 evidence (Denys et al. 1998Jones et al. 2008; Calabro et al. 2014) that implantation of intrathecal baclofen pump, while effective in managing spasticity, may cause difficulties with erection and sexual function.

There is level 4 evidence (Lombardi et al. 2008) that implanting a sacral neuromodulator can improve sexual health and ability to achieve and maintain erection in men with SCI.