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

Phase 4RecruitingNCT07803276

Universidade Federal Fluminense40 enrolled

Overview

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 Type

INTERVENTIONAL

Allocation

Purpose

TREATMENT

Masking

NONE

Enrollment

Conditions

Spastic Paraplegia

Interventions

AbobotulinumtoxinA - Ultrasound-Guided TechniqueDRUG

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

AbobotulinumtoxinA - Conventional TechniqueDRUG

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.

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

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

Locations (1)

Instituto de Neurologia Deolindo Couto

Rio de Janeiro, Rio de Janeiro, Brazil

RECRUITING

Outcomes

Primary Outcomes

Change in spasticity after BoNT-A injection techniques

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)

Time frame: Baseline and 4 weeks after each injection session

Functional improvement assessed by Goal Attainment Scaling

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)