How botulinum toxin treatment affects people with involuntary neck movements (cervical dystonia)

ISRCTN	ISRCTN11389213
DOI	https://doi.org/10.1186/ISRCTN11389213
ClinicalTrials.gov (NCT)	Nil known
Clinical Trials Information System (CTIS)	Nil known
Protocol serial number	Nil known
Sponsors	Joseph Strus Municipal Hospital, Poznan University of Medical Sciences
Funder	Investigator initiated and funded

Submission date: 18/10/2025
Registration date: 22/10/2025
Last edited: 22/10/2025

Recruitment status: Recruiting
Overall study status: Ongoing
Condition category: Nervous System Diseases

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Plain English summary of protocol

Background and study aims
Some people develop a condition called cervical dystonia, which causes involuntary muscle contractions in the neck. This can lead to abnormal head posture and neck pain. The most effective treatment is injecting botulinum toxin type A into specific neck muscles to help them relax.
This study aims to understand how this treatment affects not just movement and muscle control, but also psychological wellbeing, nervous system function, and certain blood markers. Researchers hope this will improve understanding of how the treatment works and help identify signs that show whether it’s working well.

Who can participate?
Adults aged 18–75 years diagnosed with idiopathic cervical dystonia (meaning the cause is unknown) may be eligible to take part.

What does the study involve?
Participants are assessed before and after receiving their usual botulinum toxin treatment. This includes a neurological examination, psychological and nervous system testing, and blood tests to look at biochemical markers.

What are the possible benefits and risks of participating?
There may be no direct benefit to participants, but the results could help improve future treatment and understanding of cervical dystonia. Risks are minimal and mainly related to standard medical procedures like blood tests.

Where is the study run from?
The study is being carried out at the Department of Neurology and Occupational Therapy at the Karol Marcinkowski Medical University in Poznań, Poland.

When is the study starting and how long is it expected to run for?
June 2023 to May 2027

Who is funding the study?
Investigator initiated and funded

Who is the main contact?
1. Dr A. Drużdż, adruzdz@op.pl
2. Dr M. Dudzic, gosiadudzic@gmail.com

Contact information

Dr Artur Drużdż
Scientific

Szwajcarska 3
Poznań
61285
Poland

ORCID ID	0000-0002-4479-4135
Phone	+48 (0)502121222
Email	adruzdz@szpital-strusia.xn--pozna-07a.pl

Dr Małgosia Dudzic
Public

Szwajcarska 3
Poznań
62020
Poland

Phone	+48609050376
Email	gosiadudzic@gmail.com

Prof Katarzyna Hojan
Principal investigator

Święcickiego 6
Poznań
60781
Poland

Phone	+48 (0)601509967
Email	Khojan@ump.edu.pl

Study information

Primary study design	Observational
Study design	Observational prospective pre–post comparison study
Secondary study design	Cohort study
Study type	Participant information sheet
Scientific title	Comprehensive assessment of patients with cervical dystonia treated with botulinum toxin, including neurological examination, functional and neurophysiological tests, radiological findings, serum biochemical concentrations, and neuropsychological tests
Study objectives	The project aimed to comprehensively evaluate patients with dystonia treated with botulinum toxin in the NHF therapeutic program. Most of the examinations were conducted twice – before and after botulinum toxin administration. The evaluation included: 1. Neurological examination 2. Functional examination 3. Neurophysiological examination 4. Radiological examination 5. Serum biochemical concentrations 6. Neuropsychological examination
Ethics approval(s)	Approved 29/06/2023, Bioethics Committee of the Karol Marcinkowski Medical University in Poznań (Bukowska 70, Poznań, 60-820, Poland; +48 (0)618547336; bioetyka.ump@ump.edu.pl), ref: No. 523/2023
Health condition(s) or problem(s) studied	Idiopathic cervical dystonia
Intervention	The study will involve patients with cervical dystonia receiving standard injection therapy as part of the National Health Fund (NHF) treatment program. Based on available documentation collected in accordance with the NHF's needs, a selected group of patients meeting the inclusion criteria will be asked about participation in the study following their previous injection. After obtaining initial consent, they will be informed about the study according to the study protocol and will have time to review it. After providing initial consent, upon arrival for their scheduled treatment, they will be re-reviewed, allowed to ask questions, and required to sign a consent form. The study will be conducted twice – before the scheduled botulinum toxin administration – in accordance with the NHF program (the toxin doesn't work) and after 4-6 weeks (the toxin works best). The order may be reversed. Patients will only be observed twice during visits when the toxin has finished its action and when it has its best effect. The following data and results will be collected: 1. A questionnaire survey to determine age, gender, education, type of work, time of onset of the first symptoms of dystonia, date of diagnosis, comorbidities, and medications used for chronic and acute treatment. Typical scales of CD – classification of Col-Cap and Toronto. 2. Neuropsychological tests to assess cognitive function and assessment of the severity of anxiety disorders, depression, pain, sleep disorders. 3. Functional assessment – mobility and posture examination. 4. Assessment of autonomic nervous system. 5. Blood tests 6. Analysis of radiological examinations routinely performed as part of the mandatory qualification for treatment (MR or CT of the head or neck). 7. Muscle examination using ultrasound. 8. Neurophysiological examination: assessment of muscles in EMG (F and M waves, SSR), CSP (Cutaneous Silence Period). The collected data will be statistically analyzed and correlated with each other.
Intervention type	Biological/Vaccine
Phase	Not Applicable
Drug / device / biological / vaccine name(s)	Botulinum toxin
Primary outcome measure(s)	Measured before and after botulinum toxin administration: 1. Neuropsychological tests: 1.1. Cognitive function assessed using the Montreal Cognitive Assessment (MoCA), Mini Mental State Examination (MMSE), ACE-I EpiTrack 1.2. Anxiety disorders assessed using the Liebowitz Social Anxiety Scale 1.3. Depression assessed using the Beck Depression Scale 1.4. Pain assessed using the Numerical Rating Scale (NRS) 1.5. Sleep disorders assessed using the Epworth Sleep Scale 2. Functional assessment – mobility and posture examination: 2.1. Posturography: 2.1.1. Average displacement velocity (anteroposterior [AP] and mediolateral [ML]) 2.1.2. Path length 2.1.3. Romberg index 2.1.4. Root mean square (RMS) (AP and ML) 2.2. Up-And-Go Test 2.3. Tinetti test 3. Schellong test: 3.1. Systolic blood pressure (SBP) 3.2. Diastolic blood pressure (DBP) 3.3. Heart rate (HR) Measured during lying and standing position 4. Laboratory tests: S100 calcium-binding protein B (S100B molecule), neuron-specific enolase (NSE), occludin (OCLN), claudin-5 (CLN5), zonula occludens-1 (zo-1), sPECAM-1, sICAM-1, myoglobin, creatine kinase CK, light neurofilaments, creatinine and eGFR, urea, sodium, potassium, iron, ferritin, blood count 5. Ultrasound of cervical muscles assessed using the Hakkmatt scale 6. Neurophysiological study: 6.1. F wave 6.2. M wave 6.3. Cut. Silent Period 6.4. Symp. Skin. Response
Key secondary outcome measure(s)	1. Clinical severity of cervical dystonia assessed using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) before and after botulinum toxin administration 2. Patient-reported quality of life measured using Cervical Dystonia Questionnaire (CDQ-24) before and after botulinum toxin administration
Completion date	31/05/2027

Eligibility

Participant type(s)	Healthy volunteer, Patient
Age group	Adult
Lower age limit	18 Years
Upper age limit	75 Years
Sex	All
Target sample size at registration	100
Total final enrolment	72
Key inclusion criteria	1. Ability to provide written informed consent 2. Adults (18–75 years) diagnosed with idiopathic cervical dystonia 3.Eligible for botulinum toxin type A treatment
Key exclusion criteria	1. Secondary or symptomatic dystonia 2. Other neurological or psychiatric disorders 3. Recent medication changes affecting motor or cognitive function 4. Contraindications to botulinum toxin therapy
Date of first enrolment	26/07/2023
Date of final enrolment	31/12/2026

Locations

Countries of recruitment

Poland

Study participating centres

Karol Marcinkowski Medical University in Poznań

Department of Occupational Therapy
6 Święcicki Street
Poznań
60-781
Poland

Municipal Hospital

Department of Neurology
Szwajcarska 3
Poznań
61-285
Poland

Results and Publications

Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not expected to be made available
IPD sharing plan	Individual participant data will not be publicly available due to privacy and ethical restrictions. However, anonymised datasets may be shared upon reasonable request to the corresponding author for research purposes consistent with ethical approval.

Study outputs

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Results article		06/08/2025	20/10/2025	Yes	No
Participant information sheet	Participant information sheet	11/11/2025	11/11/2025	No	Yes
Protocol file			22/10/2025	No	No
Protocol file			22/10/2025	No	No

Additional files

48223_PROTOCOL_Polish.pdf: Protocol file
48223_PROTOCOL_English.pdf: Protocol file