For some people with SCI, spasticity never really comes under control. The oral medications help — until the dose it takes to quiet the spasms also leaves you too foggy, weak, or exhausted to get through the day. When pills hit that wall, an intrathecal baclofen (ITB) pump is often the next conversation. It delivers the same drug, but directly into the spinal fluid, at a tiny fraction of the dose.
This covers what the pump is, how you find out whether it'll work for you before committing to surgery, what it can change, and the risks worth understanding first.
What an ITB Pump Is
An ITB pump is a surgically implanted device — about the size of a hockey puck — placed under the skin of the abdomen. A thin catheter runs from the pump around to the intrathecal space surrounding the spinal cord, where the cerebrospinal fluid (CSF) circulates. The pump holds a reservoir of liquid baclofen and is programmable: a clinician sets how much it releases and when, and can adjust the dose up or down over time without further surgery.
Because the drug is delivered straight to where it acts — the GABA-B receptors in the spinal cord — the doses are roughly 100 to 1,000 times smaller than what you'd swallow as a pill. That's the whole point: comparable or better spasticity control with far less of the sedation, weakness, and cognitive fog that limit high-dose oral baclofen.
How It Works
- A small programmable pump sits under the skin of the abdomen, with a reservoir that's refilled through the skin with a needle.
- A catheter carries baclofen from the pump to the intrathecal space around the spinal cord.
- The pump delivers a steady dose 24/7 — or a variable schedule (for example, more at night when spasms disrupt sleep, less during the day).
- A physiatrist or neurologist programs and fine-tunes the dose at follow-up visits — no surgery needed to change the dose.
The Screening Trial Comes First
You don't go straight to an implanted pump. The standard first step is a screening trial — a test dose to see whether intrathecal baclofen actually helps your spasticity, and how you tolerate it, before anyone commits to surgery.
In the most common version, a clinician injects a test dose of baclofen into the intrathecal space through a lumbar puncture (a needle in the lower back), then watches over the next several hours as the drug takes effect. Some centers instead place a temporary catheter to trial a continuous infusion over a day or two. Either way, the team measures your spasticity before and after — often using the Modified Ashworth Scale, a standard rating of muscle tone — to document the change.
Many people with SCI see a clear, sometimes dramatic, drop in spasticity during the trial. A good response is what tells you and your team a permanent pump is worth doing. If the trial doesn't help much, or the side effects outweigh the benefit, that's valuable information you got without major surgery.
Who It's For — and Who It Isn't
ITB is generally considered for severe, refractory spasticity — spasticity that interferes with sleep, positioning, transfers, wheelchair use, hygiene, or adaptive activities, and that oral medications, Botox, and therapy haven't adequately controlled (or only control at a dose that causes intolerable side effects). It's a well-established option in chronic SCI; many people get pumps years after injury, once it's clear the spasticity is a long-term problem.
But it isn't right for everyone. Factors that affect candidacy include:
- Overall health and fitness for surgery
- Infection risk — an implanted device with an open route to the CSF raises the stakes
- Enough body size to hold the pump comfortably
- The ability to reliably attend refill and follow-up appointments — a pump that runs dry is a medical emergency (see Risks)
Because of all this, candidacy is decided by a multidisciplinary team — typically a physiatrist or spasticity specialist together with a neurosurgeon, and often with input from others on your care team. Urology is a common one, since spasticity, bladder function, and intrathecal baclofen can interact.
What It Can Improve
For appropriately selected people, the pump can be genuinely life-changing. Reported benefits include:
- Effective spasticity control — especially for severe spasms that disrupt sleep, make transfers dangerous, or interfere with sitting and positioning
- Fewer systemic side effects than high-dose oral baclofen — less whole-body drowsiness, weakness, and fog, because the dose is so much smaller
- Easier daily care — many caregivers report transfers, dressing, and hygiene become easier when severe tone eases
- Better sitting tolerance and comfort in the chair
- Less pain from spasms, and better sleep
- Secondary gains for some people — improved overall comfort, and at times benefits for bladder function
Studies and patient reports describe high satisfaction among people with chronic SCI whose spasticity wasn't controlled by pills, injections, or therapy alone. Complications do happen (below), but willingness to continue the therapy tends to be high — because the day-to-day benefit is so tangible.
Refills, Battery & Upkeep
Two ongoing realities come with a pump:
- Refills: the reservoir is refilled in a clinic by passing a needle through the skin into the pump's fill port. Depending on your dose and the pump's capacity, refills are needed roughly every 1–6 months. Missing a refill is dangerous — running out triggers withdrawal.
- Battery & replacement: the pump battery typically lasts 5–7 years (sometimes longer). As it nears end of life, the whole pump is replaced in a relatively minor surgery; the catheter usually stays in place.
Dose changes are done in clinic by reprogramming — part of what makes the pump so adjustable over the years.
The Risks: Withdrawal & Overdose
Two risks deserve real attention.
Baclofen withdrawal (too little). If the pump malfunctions, the catheter kinks, breaks, or disconnects, or the reservoir runs dry, the supply of baclofen can stop abruptly. Intrathecal baclofen withdrawal is a medical emergency — far more dangerous than missing an oral dose. Early signs include a rebound surge in spasticity and itching (often without a rash); it can progress to high fever, altered mental status, seizures, muscle breakdown (rhabdomyolysis), and, rarely, death if not treated quickly.
Baclofen overdose (too much). A programming or pump error that delivers too much can cause excessive drowsiness, weakness, very low muscle tone, slowed breathing, and loss of consciousness.
As with any implant, there are also the ordinary surgical risks: infection (sometimes serious enough to require removing the device), bleeding, a CSF leak and spinal headache, and catheter problems that can develop over time. These are part of why the decision is made carefully with a surgical team — and why follow-up matters.
Is It Right for Chronic SCI?
If you're a few years post-injury with persistent, problematic spasticity that pills aren't handling — or are only handling at the cost of how you feel and function — the pump is a strong option to put on the table. It's commonly used in exactly this situation, including higher cervical injuries (for example, C5/6) with ongoing spasticity, and outcomes for spasticity control and daily function are generally good in well-selected people.
Success usually isn't just the device. It's the device plus continued physical and occupational therapy to turn reduced tone into real functional gains — easier transfers, better positioning, more comfortable sitting.
Questions to Ask Your Team
If you're weighing an ITB pump, these are worth raising:
- Is my spasticity severe and refractory enough to justify a pump — or are there oral or focal options (like Botox) we haven't fully tried?
- Can we do a screening trial so I can see the effect before committing?
- How might the pump affect tone I actually use — for transfers, standing, or positioning?
- What's the realistic refill schedule, and where would I go for refills and for emergencies?
- What's your center's experience and complication rate, and do you have long-term data for injuries at my level?
- How does this interact with my bladder management?
Sources & Further Reading
This page combines lived SCI experience with published clinical guidance, including:
- Spasticity and Spinal Cord Injury — Model Systems Knowledge Translation Center (MSKTC) (see the factsheet library)
- Today's Care — Christopher & Dana Reeve Foundation
- Clinical Practice Guidelines library — Consortium for Spinal Cord Medicine Clinical Practice Guidelines (Paralyzed Veterans of America)
This is not medical advice. An ITB pump is a major decision that should be made with qualified SCI specialists who know your full history, current function, and goals. Practice varies by injury level, provider, and institution — always confirm specifics with your own care team.