Comparison Between Palpatory and Ultrasound-guided Methods for Botulinum Toxin Administration in Spastic Paraplegia

September 1, 2026 updated by: Universidade Federal Fluminense
Spasticity in spastic paraplegia is a major cause of chronic pain and functional limitation. Although botulinum toxin type A (BoNT-A) reduces muscle tone, studies like the SPASTOX trial have shown limited functional improvement, which may be related to injection accuracy in deep or complex muscle groups. Ultrasound guidance enhances injection precision, potentially improving clinical outcomes. This prospective, single-group, fixed-sequence crossover study ($N = 40$) aims to compare the response to BoNT-A in patients with spastic paraplegia (all etiologies included). Participants will receive treatment in two distinct phases separated by a 16-week washout period: first with conventional anatomical landmark-guided injections, followed by ultrasound-guided injections. A fixed sequence (anatomical first, ultrasound second) is used to prevent observer bias, ensuring the injector remains blinded to muscle ultrasound features (e.g., fatty infiltration or fibrosis) during the landmark-guided phase. Both the participants and the outcome assessor are blinded to the application sequence. Assessments will occur before and 4 weeks after each intervention using validated tools, including the Modified Ashworth Scale, Goal Attainment Scaling (GAS), Timed Up and Go (TUG), Visual Analog Scale (VAS) for pain, modified Barthel Index, SF-36 questionnaire, and the Heckmatt scale. The hypothesis is that ultrasound-guided injections will achieve greater spasticity reduction and functional recovery.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

40

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • Brazil
    • Rio de Janeiro
      • Rio de Janeiro, Rio de Janeiro, Brazil, 22290-140
        • Recruiting
        • Instituto de Neurologia Deolindo Couto
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria

  • Age over 18 years
  • Clinical diagnosis of spastic paraplegia
  • Spasticity with Ashworth Scale score between 2 and 3 in at least one muscle group with indication for botulinum toxin treatment
  • Muscle strength ≥ 3 on the Muscle Strength Assessment Scale
  • Enrollment in a rehabilitation program
  • For women of childbearing potential, a negative beta-hCG test at the time of injection

Exclusion Criteria

  • Concomitant neuromuscular disorders
  • History of hypersensitivity to botulinum toxin
  • Active infection at the injection site
  • Ashworth Scale score of 4
  • Pregnancy or breastfeeding

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Spastic Paraplegia Cohort (Anatomical Toxin Injection followed by USG-Guided Injection)

Participants with spastic paraplegia receive two sequential treatments separated by a 16-week washout period:

First intervention: AbobotulinumtoxinA injection using the conventional anatomical/palpation technique.

Washout period: 16 weeks. Second intervention: AbobotulinumtoxinA injection using the ultrasound-guided technique
Drug: AbobotulinumtoxinA - Ultrasound-Guided Technique
Administration of AbobotulinumtoxinA (500U) into spastic lower limb target muscles under real-time ultrasound guidance to ensure precise muscle localization. Performed 16 weeks after the first intervention. Assessments are performed pre-injection and 4 weeks post-injection
Drug: AbobotulinumtoxinA - Conventional Technique
Administration of AbobotulinumtoxinA (500U) into spastic lower limb target muscles using standard anatomical landmarks and manual palpation. Assessments are performed at baseline and 4 weeks post-injection.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in spasticity after BoNT-A injection techniques
Time Frame: Baseline and 4 weeks after each injection session
Change in spasticity measured by the Modified Ashworth Scale (MAS), comparing conventional landmark-guided versus ultrasound-guided botulinum toxin type A injections in patients with spastic paraplegia. The Modified Ashworth Scale ranges from 0 to 4, with higher scores indicating greater muscle tone/spasticity (worse outcome)
Baseline and 4 weeks after each injection session
Functional improvement assessed by Goal Attainment Scaling
Time Frame: Baseline and 4 weeks after each intervention

Functional improvement assessed by Goal Attainment Scaling (GAS) after conventional landmark-guided versus ultrasound-guided botulinum toxin type A injections.

The Goal Attainment Scaling score ranges from -2 to +2, with higher scores indicating greater achievement of the predefined treatment goals (better outcome)
Baseline and 4 weeks after each intervention
Functional mobility assessed by the Timed Up and Go Test
Time Frame: Baseline and 4 weeks after each intervention

Change in functional mobility measured by the Timed Up and Go (TUG) Test, comparing conventional landmark-guided versus ultrasound-guided botulinum toxin type A injections.

The Timed Up and Go Test is measured in seconds, with lower times indicating better functional mobility (better outcome)
Baseline and 4 weeks after each intervention
Change in functional independence assessed by the Modified Barthel Index
Time Frame: Baseline and 4 weeks after each intervention

Change in functional independence measured by the Modified Barthel Index, comparing conventional landmark-guided versus ultrasound-guided botulinum toxin type A injections.

The Modified Barthel Index ranges from 0 to 100, with higher scores indicating greater functional independence (better outcome).
Baseline and 4 weeks after each intervention

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Pain intensity after BoNT-A injection techniques
Time Frame: Baseline and 4 weeks after each intervention
Change in pain intensity measured by the Visual Analog Scale (VAS). The Visual Analog Scale ranges from 0 to 10, with higher scores indicating greater pain intensity (worse outcome)
Baseline and 4 weeks after each intervention
Quality of life after BoNT-A injection techniques
Time Frame: Baseline and 4 weeks after each intervention

Change in quality of life assessed by the 36-Item Short Form Health Survey (SF-36).

The SF-36 assesses eight health domains, with scores ranging from 0 to 100 for each domain. Higher scores indicate better health status (better outcome)
Baseline and 4 weeks after each intervention
Adverse events related to BoNT-A injection techniques
Time Frame: Up to 16 weeks after each injection
Incidence and severity of adverse events associated with conventional landmark-guided and ultrasound-guided botulinum toxin type A injections
Up to 16 weeks after each injection

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Universidade Federal Fluminense

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

April 22, 2026

Primary Completion (Estimated)

February 1, 2027

Study Completion (Estimated)

May 1, 2027

Study Registration Dates

First Submitted

August 24, 2026

First Submitted That Met QC Criteria

September 1, 2026

First Posted (Actual)

September 3, 2026

Study Record Updates

Last Update Posted (Actual)

September 3, 2026

Last Update Submitted That Met QC Criteria

September 1, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 90758725.3.0000.5243

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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