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 Table of Contents  
Year : 2022  |  Volume : 5  |  Issue : 5  |  Page : 50-60

Module 4: Optimizing outcomes in spasticity treatment

1 Department of Physical Medicine and Rehabilitation, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
2 Department of Clinical Neurosciences, Service of Neuropsychology and Neurorehabilitation, Lausanne University Hospital (CHUV), Lausanne, Switzerland
3 Department of Rehabilitation Medicine, Weill Cornell Medicine, New York, USA
4 Rehdo Rehabilitation Centre, Gothenburg, Sweden
5 Alcoitão Medical Rehabiliation Centre, Rua Conde Barão, Alcabideche, Portugal
6 Medecine Physique and Readaptation, Université catholique de Louvain, Centre Hospitalier Universitaire de Namur, Site Godinne, Yvoir, Belgium
7 Department of Physical Medicine and Rehabilitation, McGovern Medical School, University of Texas Health Science Center; Department of Physical Medicine and Rehabilitation, UTHealth Houston McGovern Medical School and TIRR Memorial Hermann Hospital, Houston, Texas, USA

Date of Submission14-Nov-2021
Date of Decision13-Dec-2021
Date of Acceptance14-Dec-2021
Date of Web Publication20-Jun-2022

Correspondence Address:
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/2349-7904.347810

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With many recent advancements in spasticity treatment, more patients are surviving critical illness and injury but are left with ongoing disability that needs constant treatment. Such treatment will change as the patient's condition evolves. Constant appraisal of treatment efficacy and patient progress is therefore an important component of spasticity management, and physicians need to be familiar with how to troubleshoot treatment regimens when outcomes of that regimen become suboptimal. This module considers how to optimize the use and outcomes of major treatment modalities and provides drug and device maintenance algorithms to guide the treating team.

Keywords: Troubleshoot- spasticity treatment regimens - suboptimal outcomes - Muscle spasticity - Treatment outcome - Baclofen/adverse effects - Implantable/adverse effects - Botulinum toxins/adverse effects - Muscle relaxants, central/adverse effects

How to cite this article:
Ketchum N, Carda S, O’Dell MW, Säterö P, Jacinto J, Deltombe T, Francisco GE. Module 4: Optimizing outcomes in spasticity treatment. J Int Soc Phys Rehabil Med 2022;5, Suppl S1:50-60

How to cite this URL:
Ketchum N, Carda S, O’Dell MW, Säterö P, Jacinto J, Deltombe T, Francisco GE. Module 4: Optimizing outcomes in spasticity treatment. J Int Soc Phys Rehabil Med [serial online] 2022 [cited 2023 Feb 1];5, Suppl S1:50-60. Available from: https://www.jisprm.org/text.asp?2022/5/5/50/347810

  Learning Objectives Top

Upon completion of this module, the learner will be able to:

  1. Identify reasons why botulinum toxin, intrathecal baclofen therapy, oral medications, or phenol/alcohol treatment are producing suboptimal outcomes
  2. Discuss the need for constant reappraisal of the patient – goals, progress, and concomitant conditions
  3. Enumerate ways to troubleshoot suboptimal outcomes of spasticity treatment.

  Addressing Suboptimal Outcomes of Spasticity Interventions Top

By its very nature, spasticity treatment is not a single, isolated, intervention but continues over months and years. Treatment will also progress over time and different treatment modalities will be employed as the patient's condition changes. It is not unusual for a seemingly effective treatment to start to show decreased efficacy and it is important therefore to be able to troubleshoot why efficacy is waning before making radical alterations to the care plan. Equally, treatments can produce over responses and these must be addressed before plans are changed. Side effects of treatments and other developing neurological conditions can also affect treatment outcomes.

Suboptimal outcome following any treatment modality can have multiple etiologies. Concerns that the usual treatment is producing suboptimal outcomes may be raised by the patient, their family and/or carers, or the treating physician.

When a patient is reporting a poorer effect than expected it is important to:

  • Listen to their concerns to help identify the problems
  • Review previously agreed upon goals
  • Ask if they think the treatment did not work at all
  • Enquire if the effect wore off too fast
  • Establish if the treatment is no longer working after experiencing good effects in previous cycles
  • Elicit adverse effects, such as increased weakness
  • Consider other side effects related to the treatment, among others.

Listening to patients' concerns expressed in their own terms may provide clues and help point to a real lack of efficacy of the spasticity treatment, or if another problem is impinging on the patient's condition and causing a temporary increase in the spasticity. A good first step is to review the previously agreed upon goals and the treatment objectives should be reviewed and documented. Goals of treatment should be reviewed using the SMARTER goal system (Specific Measurable Achievable Realistic Timely Ethical Recorded) (see Module 1 in this Supplement).

It should be considered whether the goals were appropriate and whether the patient and/or their carer were motivated to achieving these goals. Furthermore, patient expectations may change over time and it is important to assess how the patient views their progress and the future.

The information previously discussed with the patient about their spasticity and how the treatment acts to address the problem should be re-iterated. It is important to use patient-friendly language and vocabulary; “patient-like wording” instead of medical terminology ensures clearer communication.[1]

It is telling that in a recent international survey of patients living with spasticity, 45% of respondents reported dissatisfaction with the information provided at diagnosis. Of these, 67% wanted more information; 36% felt the clinician used too many technical words or there were problems with communication; and 35% wanted more time with their doctor to better understand their diagnosis and its future consequences. Only 5% were overwhelmed by the information provided.[2]

For treatments that are repeated at regular intervals, such as botulinum toxin injections, it may be an issue of the frequency of treatment schedules. For continuous systems such as baclofen pumps that also rely on properly functioning equipment; there are other considerations.

  Treatment Algorithms Top

[Table 1] is a comprehensive listing all the items that need to be considered when assessing under response or over response to spasticity treatments.[3],[4],[5],[6],[7],[8],[9],[10],[11],[12] The clinical treatment algorithms [Figure 1],[Figure 2],[Figure 3],[Figure 4] will provide guidance to which items need to be reviewed under different circumstances – considering both treatment modality and the nature of the problem.
Figure 1: Algorithm for troubleshooting oral medications

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Figure 2: Algorithm for troubleshooting of suboptimal neurotoxin outcomes after the initial treatment session

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Figure 3: Algorithm for troubleshooting suboptimal neurotoxin outcomes after subsequent treatment sessions

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Figure 4: Algorithm for troubleshooting of suboptimal alcohol/phenol outcomes

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Table 1: Items for consideration when troubleshooting spasticity treatment

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In addition, there are special considerations for maintaining and troubleshooting intrathecal baclofen pumps and these are considered separately [Figure 5] and [Figure 6].
Figure 5: Algorithm for troubleshooting suboptimal outcomes of intrathecal baclofen therapy

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Figure 6: Algorithm for troubleshooting intrathecal baclofen pump malfunction[16]

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Troubleshooting oral medications

Once the goals have been reviewed, it is necessary, as with any oral regimen, to ensure that the patient is showing compliance with the treatment and taking medication regularly and as prescribed. The dose and timing of the medication should be reviewed.

The patient's overall condition in terms of spasticity progression and other medical comorbidities should be assessed and their spasticity medication adjusted accordingly with referral or additional prescribing for comorbidities.

The algorithm provides guidance on items to review.

  Troubleshooting Botulinum Toxin A/Phenol/Ethanol Injections Top

BoNT-A and neurolytic agents are injected at multiple sites which raise issues such as: Were the muscles targeted correctly related to the goals; was the muscle localization technique adequate; were doses per muscle adequate or underdosed; was the adjunctive therapy carried out; was there any concurrent event that might have influenced a poor outcome?

In cases of suboptimal response to treatment important areas to address include;

  • Goals
  • Technique
  • Concentration
  • Volume
  • Progression of disease
  • Nerve/muscle selection.

Spasticity not the main issue in cases of exaggerated response (e.g., probable overdose), the areas to evaluate include:

  • Goals
  • Unmasking weakness
  • Progression of disease
  • Nerve/muscle selection
  • Spasticity not the main issue.

The algorithms address troubleshooting after the first treatment session and after subsequent treatment sessions.

Troubleshooting after alcohol/phenol injections follows a similar pathway.

  Approach to Troubleshooting Intrathecal Baclofen Systems Top

Intrathecal baclofen is an effective means of managing severe problematic spasticity in patients. However, these systems can malfunction either acutely or over time. Knowing how to troubleshoot these systems can improve patient outcomes and minimize morbidity in a comprehensive spasticity management practice.

Decreased response, review:

  • Pump problem or not?
  • Goals
  • Concomitant medical issue
  • Disease Progression
  • Spasticity not the main issue.

Excessive response, review:

  • Pump problem or not?
  • Goals
  • Unmasking weakness
  • Progression of disease
  • Spasticity not the main issue.

In addition:

  • Acute withdrawal versus decreased control of spasticity over time.

  Assessing Pump Problems Top

Because of the nature of intrathecal baclofen systems, troubleshooting of these systems necessitates special consideration. Two best practice algorithms for troubleshooting intrathecal baclofen therapy were published in 2016.[16] The first was for loss-of-efficacy and applies to patients with previously well-controlled hypertonia on a stable dosing regimen who have increased spasticity. The second algorithm was for emergent care and describes treatment of overdose or withdrawal, which requires immediate care in a monitored setting and restoration of baclofen delivery. They also address suspected overdose or over-infusion.

These algorithms provide a useful basis for troubleshooting; however, local resources vary and each treatment center or practice will need to develop their own pathway for troubleshooting that uses their own resources to best advantage.

  Troubleshooting Intrathecal Baclofen Therapy-related Problems Top

Three main scenarios when troubleshooting is indicated are:

  • When there is suspicion of medication overdose or pump over infusion
  • Medication withdrawal or pump under infusion
  • Loss of efficacy of the therapy over time.

However, many things can mimic baclofen overdose or underdose. The first step in any trouble setting algorithm is identifying other medical issues which weight may be masquerading as an intrathecal baclofen system malfunction.

Thankfully, baclofen overdose is a rare entity. The etiologies are typically programming error, using the wrong medication concentration, and very rarely, is the phenomenon of device over infusion.

Troubleshooting an intrathecal system is indicated when medication overdose or over-infusion is suspected, when withdrawal or under-infusion is suspected or when efficacy of the medication has decreased over time.[16]

As a first step conditions that mimic incorrect dosing must be eliminated to help confirm that the problem really lies in the pump or catheter delivery. Some conditions can confound identification of the problem as they may produce the same symptoms. For example, withdrawal or increased spasticity may be mimicked by autonomic dysreflexia, serotonin syndrome, noxious stimuli, urinary tract infections (UTIs), or constipation. Overdose or decreased spasticity may be mimicked by multiple sclerosis (MS) exacerbation, a new neurologic event (i.e., stroke), or excessive oral medication.

  Overdose Top

The signs or symptoms of baclofen overdose include dizziness, somnolence, hypotonia, respiratory depression, seizures, and coma. This can arise when the apparatus is programmed incorrectly by the user (e.g., entering 500 mcg/day instead of 50 mcg/day). Errors can also be made in drug concentration (e.g., using medication of concentration 2000 mcg/mL rather than 500 mcg/mL). More rarely, the pump may deliver too much medication but this has been reported in < 0.16% of cases (Implantable Systems Performance Registry, August 2003 to July 2015, Medtronic).

The management of baclofen overdose is to maintain airway/breathing/circulation and decrease the intrathecal dose by programming the pump to minimum rate or withdrawal of large volume lumbar puncture (LP)/catheter access port (CAP). It should be noted, following a dramatic ITB dose reduction, the patient must be assessed and treated for symptoms of baclofen withdrawal. However, these symptoms should be self-limited.[16]

  Underdose Top

Withdrawal or under-infusion symptoms include rebound spasticity, pruritis without a rash, mental status changes, fever, or even death.

As with overdosing, a programing error may be responsible for underdosing (e.g., entering 50 mcg/day instead of 500 mcg/day) or errors can be made in the drug concentration (e.g., using medication with 500 mcg/mL concentration instead of 2000 mcg/mL).

If human error is not responsible, the device may have a malfunction (i.e., critical motor stall) or an empty pump reservoir if the patient or caregiver has missed the alarm date or a refill appointment. The pump may be at the end of its useful service period. Typically, device batteries have a life of approximately 7 years and the device needs to be replaced before the end of battery life. Catheters may also be the source of system malfunction if they become occluded, kinked, or disconnected. One other source of underdosing can result from the so-called “pocket fill.” In these cases, the refill needle may become dislodged from or never be properly located in the pump reservoir. When this happens, the medication gets delivered subcutaneously rather than into the pump.

A loss of efficacy may also present slowly as a change over time rather than acute withdrawal. This is seen when the ITB does not give the same effect on spasticity as was achieved with the test dose despite dose escalation. A diminishing effect of the medication on spasticity where there was previous good control can also indicate loss of efficacy.[16]

Apparent loss of efficacy could be due to disease progression or MS exacerbation or other medical issues such as constipation or a deep vein thrombosis.

Baclofen withdrawal or under-infusion should be managed by administering an intrathecal bolus of the medication. Restoring the intrathecal delivery of baclofen is first step if possible, using LP, external indwelling catheter, or pump (if known to be functioning).

Oral or enteral baclofen is another option; if the patient is able to take the medication oral administration is the simplest or, if a percutaneous endoscopic gastroscopy tube is present, this can be utilized. There is no intrathecal to oral conversion; typically, the patient should be given the preimplant dose. If the prior dose not known, 10–20 mg every 6 h should be considered.

Intravenous benzodiazepines are an option but these need cardiac/respiratory monitoring. They can also be prophylactic for seizures. Cyproheptadine may be given at 2–4 mg every 6 h.

Creatine kinase and renal function should be monitored and the patient assessed for rhabdomyolysis.

The “syndromes” associated with catheter malfunction are given in [Table 2] and the incidence of catheter malfunction is given in [Table 3].
Table 2: “Syndromes” associated with catheter malfunction

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Table 3: The incidence of catheter malfunction

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Some of the important points to consider are outlined here.

Firstly, as the data above have shown, most of the time a patient's, caregiver's, or other provider's concern of increased spasticity is NOT a pump or a catheter problem. Hence, patients must be assessed for their recent medical history, paying attention to any illnesses, medication changes, or environmental changes. Compare the spasticity on examination to prior examinations. For many patients, intrathecal baclofen withdrawal is often described as “worse than before getting the pump.” The patient should be assessed for changes in mental status and review whether there is a source of noxious stimuli.

While problems with the pump itself are rare, inaccurate programming is often the culprit. It is important to verify the actual drug and concentration put in the pump. If the pump alarm is sounding, the pump may be empty, at the end of battery life, or experiencing motor stalling. The pump log should be checked.

The pump volume must be checked since it does not have a “fuel gauge.” There may be too little drug in the reservoir due to “pocket fill.” If this problem is leading to subcutaneous delivery of baclofen, it would be poorly absorbed and not lead to overdose. Downstream obstruction in the system could lead to a higher-than-expected volume.

The CAP must be checked using the specified kit to access the CAP. This is the only needle that can access the CAP – the refill needle cannot be used. A total of 2–3 mL of fluid should be aspirated, all the baclofen in the catheter will have been withdrawn after the first ~0.25–0.5 mL, and the system will be withdrawing cerebrospinal fluid (CSF). Inability to aspirate easily suggests obstruction downstream and the catheter MUST be replaced.

It is important to program a priming bolus if the system is flowing freely and drug/CSF are withdrawn. Forgetting to perform a priming bolus can lead to withdrawal since the spinal catheter will be empty.

Imaging is useful to confirm what components of the system are implanted. Some components (Medtronic Ascenda™ catheter) are less visible on plain films. A computed tomography (CT) myelogram/Dye Study may be necessary. It is important to make sure that the catheter is aspirated via CAP before instilling dye. Radiopaque dye may be instilled under fluoroscopy or dye may be instilled in the CT scanner immediately before scan.

When programming the bolus dose, the same dose as the test dose should be used if the patient is not currently receiving bolus medication. The clinical response to bolus administration should be assessed where soleus H-reflexes can be useful as they are sensitive to intrathecal baclofen.[18]

It must be remembered that the algorithm is only an example. Local resources must be employed and the algorithm modified to produce an acceptable way to troubleshoot the system. Consideration should be given to team members skill in accessing the CAP, who participates in managing baclofen pump patients, whether there should be baclofen pump clinic days and education for the local emergency department.

When “inheriting” a patient with a baclofen pump, it may be worth investing some time is checking the device, verifying dose concentration etc., and ensuring that the indication for intrathecal baclofen in the first place is clear; the information should be shared with the management team.[19]

  Case History Top

Case 2

A 58-year-old male patient suffering from right sylvian ischemic stroke (right internal carotid artery dissection, happened at the age of 52) with left hemiplegia, left homonymous hemianopia, left neglect, and persistent anosognosia has been treated for severe hand spasticity with BoNT-A two times, 4 and 7 months after stroke.

He was lost at follow-up and came only 3 years later, due to a skin infection of the palm. His left hand had a severe clenched fist, and, after a new BoNT-A treatment and antibiotics, he recovered.

6 months after his treatment the patient comes back [Figure 7],[Figure 8],[Figure 9].
Figure 7: (a and b) Left-hand posture 6 months after last BoNT-A treatment

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Figure 8: The result of this treatment 4 weeks after last BoNT-A treatment. The patient is quite disappointed about his hand posture

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Figure 9: Four months after. The same patient, two weeks after having repeated the same BoNT-A treatment but this time with the addition of taping for 7 days

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He was treated with incobotulinumtoxinA, under ultrasound guidance, to the following muscles:

  • Interossei: 80 UI
  • FDS: 190 UI
  • FDP: 60 UI
  • FPL: 20 UI.

Dilution was 1 ml 0.9% saline: 100 UI for interossei and FPL and 2 ml 0.9% saline:100 UI for the other muscles. The primary objective was hygiene ease (opening the hand alone to clean the palm).

  Competency Assessment Top

The answers to the Competency Assessments can be found at the end of the module before the references.

  1. Which are the most frequent reason for a suboptimal outcome following BoNT-A?
  2. What conditions can mimic apparent increased spasticity in a patient treated with intrathecal baclofen?
  3. In the case history discussed above, what are the possible explanations for the result seen at 4 weeks after the last BoNT-A treatment?

  Competency Assessment Answers Top

  1. Which are the most frequent reason for a suboptimal outcome following BoNT?

Expected content of answer:

The most frequent reasons can be summarized in 3 groups:

  1. Goal-related: Revise goal appropriateness, formulation, and measurement
  2. Procedure-related: Correct muscle selection, correct targeting, correct dose
  3. Patient-related: Patient motivation, cooperation, concomitant health problems
  4. What conditions can mimic apparent increased spasticity in a patient treated with intrathecal baclofen?

Expected content of answer:

Withdrawal or increased spasticity may be mimicked by autonomic dysreflexia, serotonin syndrome, noxious stimuli, UTIs, or constipation.

3. In the case history discussed above, what are the possible explanations for the result seen at 4 weeks after the last BoNT-A treatment?

Expected content of answer:

Since the dose and dilution utilized are adequate, we should check for:

  1. Goals: Is the goal realistic? If the patient had some contractures, the result achieved is the maximum possible. Anosognosia can make harder/impossible for the patient to evaluate his improvement
  2. Procedure related: Did the patient have any adjuvant therapy?
  3. Patient-related: Which was patient's compliance with correct positioning and how did he take care of his arm after the treatment?

  References Top

Bhimani RH, McAlpine CP, Henly SJ. Understanding spasticity from patients' perspectives over time. J Adv Nurs 2012;68:2504-14.  Back to cited text no. 1
Barnes M, Kocer S, Murie Fernandez M, Balcaitiene J, Fheodoroff K. An international survey of patients living with spasticity. Disabil Rehabil 2017;39:1428-34.  Back to cited text no. 2
Turner-Stokes L, Baguley IJ, De Graaff S, Katrak P, Davies L, McCrory P, et al. Goal attainment scaling in the evaluation of treatment of upper limb spasticity with botulinum toxin: A secondary analysis from a double-blind placebo-controlled randomized clinical trial. J Rehabil Med 2010;42:81-9.  Back to cited text no. 3
Esquenazi A, Geis C, Wein T, Ward AB, Liu C, Dimitrova R. Poster 312 muscle selection patterns for injection of OnabotulinumtoxinA in adult patients with post-stroke lower-limb spasticity influence outcome: Results from a double-blind, placebo-controlled phase 3 clinical trial. PM R 2016;8:S262.  Back to cited text no. 4
Sampaio C, Ferreira JJ, Simões F, Rosas MJ, Magalhães M, Correia AP, et al. DYSBOT: A single-blind, randomized parallel study to determine whether any differences can be detected in the efficacy and tolerability of two formulations of botulinum toxin type A – Dysport and Botox – Assuming a ratio of 4:1. Mov Disord 1997;12:1013-8.  Back to cited text no. 5
Pickett A, Dodd S, Rzany B. Confusion about diffusion and the art of misinterpreting data when comparing different botulinum toxins used in aesthetic applications. J Cosmet Laser Ther 2008;10:181-3.  Back to cited text no. 6
Brodsky MA, Swope DM, Grimes D. Diffusion of botulinum toxins. Tremor Other Hyperkinet Mov (N Y) 2012;2:e-1.  Back to cited text no. 7
Ramirez-Castaneda J, Jankovic J. Long-term efficacy and safety of botulinum toxin injections in dystonia. Toxins (Basel) 2013;5:249-66.  Back to cited text no. 8
Shaari CM, Sanders I. Quantifying how location and dose of botulinum toxin injections affect muscle paralysis. Muscle Nerve 1993;16:964-9.  Back to cited text no. 9
Yaraskavitch M, Leonard T, Herzog W. Botox produces functional weakness in non-injected muscles adjacent to the target muscle. J Biomech 2008;41:897-902.  Back to cited text no. 10
Pickett A. Consistent biochemical data are essential for comparability of botulinum toxin type A products. Drugs R D 2011;11:97-8.  Back to cited text no. 11
Walter U, Mühlenhoff C, Benecke R, Dressler D, Mix E, Alt J, et al. Frequency and risk factors of antibody-induced secondary failure of botulinum neurotoxin therapy. Neurology 2020;94:e2109-20.  Back to cited text no. 12
Albrecht P, Jansen A, Lee JI, Moll M, Ringelstein M, Rosenthal D, et al. High prevalence of neutralizing antibodies after long-term botulinum neurotoxin therapy. Neurology 2019;92:e48-54.  Back to cited text no. 13
Jacinto J, Varriale P, Pain E, Lysandropoulos A, Esquenazi A. Patient perspectives on the therapeutic profile of botulinum neurotoxin type A in spasticity. Front Neurol 2020;11:388.  Back to cited text no. 14
Brashear A, Watts MW, Marchetti A, Magar R, Lau H, Wang L. Duration of effect of botulinum toxin type A in adult patients with cervical dystonia: A retrospective chart review. Clin Ther 2000;22:1516-24.  Back to cited text no. 15
Saulino M, Anderson DJ, Doble J, Farid R, Gul F, Konrad P, et al. Best practices for intrathecal baclofen therapy: Troubleshooting. Neuromodulation 2016;19:632-41.  Back to cited text no. 16
Turner MS. Assessing syndromes of catheter malfunction with SynchroMed infusion systems: The value of spiral computed tomography with contrast injection. PM R 2010;2:757-66.  Back to cited text no. 17
Stokic DS, Yablon SA. Effect of concentration and mode of intrathecal baclofen administration on soleus H-reflex in patients with muscle hypertonia. Clin Neurophysiol 2012;123:2200-4.  Back to cited text no. 18
Ngo K, McGuire JR. Poster 45: Failure to identify intrathecal baclofen pump/catheter problems can lead to unnecessary healthcare costs: A case report. Phys Med Rehabil 2009;1:S122-3.  Back to cited text no. 19


  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9]

  [Table 1], [Table 2], [Table 3]


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Troubleshooting ...
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Case History
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