Therapeutic Botulinum Neurotoxin in Parkinson’s Disease: Evidence-Based Applications and Injection Guidance

By Dr. Evan Friedman | October 18, 2025 |

Therapeutic Botulinum Neurotoxin in Parkinson’s Disease: Evidence-Based Applications and Injection Guidance

Intronix Technologies Clinical Education Series — The Myoguide Academy – Dr. Evan Friedman

Why this matters

Parkinsons Disease

 

Parkinson’s disease (PD) is among the most common neurological disorders, affecting approximately 1% of adults over 60, with progression that current therapies can slow but not stop (Parkinson, 1817; Lang & Lozano, 1998; Marras & Tanner, 2004; Van Den Eeden et al., 2003; Anandan & Jankovic, 2021). The classic neuropathology involves the loss of dopaminergic neurons in the substantia nigra pars compacta and the presence of Lewy bodies and Lewy neurites (Kouli, Torsney, & Kuan, 2018). For focal, function-limiting complications—such as tremor, dystonia (cervical, limb, oromandibular), bruxism, camptocormia, eyelid opening apraxia/blepharospasm, jaw tremor, and freezing of gait—botulinum neurotoxin (BoNT) serves as an important adjunct when it is expertly planned and precisely guided.

PD motor features (clinical context)

Cardinal signs include resting tremor, bradykinesia, and rigidity; postural instability usually appears later and is not part of many early diagnostic criteria (Marras & Tanner, 2004; Lang & Lozano, 1998; Gelb, Oliver, & Gilman, 1999).

Resting tremor is typically 4–5 Hz “pill-rolling,” often unilateral at first, worsened by distraction, and may display a re-emergent postural component that can be mistaken for essential tremor (Jankovic & Schwartz, 1991; Trosch & Pullman, 1994; Mittal, Lenka, & Jankovic, 2019; Kim et al., 2014).

Tremor can involve the lips/jaw/legs more than the head (Jankovic & Schwartz, 1991; Brin et al., 2001). Bradykinesia—characterized by reduced speed, amplitude, and difficulty initiating movement—causes disability, initially seen as loss of fine motor control, then gait changes, festination, and freezing as the condition progresses (Berardelli, Rothwell, Thompson, & Hallett, 2001).

Rigidity, whether cogwheel or lead-pipe, usually affects the same side as the tremor at first and contributes to pain and a stooped posture (Scott et al., 1970). Postural instability is evaluated with the pull test and becomes a late factor in falls and disability (van der Heeden et al., 2016).

Where BoNT helps in PD (condition-focused highlights)

Upper limb tremor with parkinsonian or dystonic features

Individualized BoNT can decrease amplitude and enhance activities of daily living when targets and doses are tailored; evidence includes RCTs and controlled series (Jankovic & Schwartz, 1991; Jankovic et al., 1996; Brin et al., 2001; Mittal et al., 2017/2019; Rahimi, Samotus, Lee, & Jog, 2015).

Blepharospasm / Apraxia of Eyelid Opening (ALO)

Pretarsal/lateral orbicularis oculi injections are standard for preventing eyelid closure or failure to reopen; ALO may occur in parkinsonism and has surgical/DBS associations (Goldstein & Cogan, 1965; Yoon et al., 2005; Krack et al., 2003; Comella et al., 1992).

Bruxism or Oromandibular Dysfunction

Masseter ± temporalis injections decrease the burden of awake and sleep bruxism in RCTs and systematic reviews (Lee et al., 2010; Shim et al., 2014; Ondo et al., 2018; Ågren, Sahin, & Pettersson, 2020).

Cervical dystonia in Parkinson’s disease

Strong evidence supports BoNT-A and BoNT-B for pain, posture, and quality of life; careful muscle selection and guidance reduce dysphagia risk and enhance response durability (Simpson et al., 2016; Kaymak et al., 2018; Colosimo et al., 2019; Truong et al., 2010; Yun et al., 2015).

Camptocormia

Selected cases benefit from iliopsoas or external oblique injections, often ultrasound-guided, with functional goal-setting (Von Coelln et al., 2008; Wijemanne & Jimenez-Shahed, 2014; Fietzek, Schroeteler, & Ceballos-Baumann, 2009).

Jaw tremor

Small case series and reports suggest benefit with tailored patterns (Schneider et al., 2006).

Freezing of gait (FOG)

Early studies show mixed results but indicate potential benefits in carefully chosen patients when calf/leg targets are selected and outcomes are tracked objectively (Fernandez et al., 2004; Vaštík et al., 2016).

Getting injections right: guidance that improves accuracy, safety, and outcomes

Electromyography (EMG) guidance

Why: Confirms the needle is in the intended muscle—and in the pathologically active portion.

Evidence: EMG guidance enhances clinical outcomes and decreases adverse effects compared to palpation in cervical dystonia (Comella et al., 1992). Even experienced practitioners conducting “blind” placements can experience mislocalization in the neck (Speelman & Brans, 1995); manual placement error rates are significant (Schnitzler et al., 2012). A systematic review found that instrumented guidance outperforms manual methods in treating focal spasticity and dystonia (Grigoriu, Dinomais, Rémy-Néris, & Brochard, 2015).

Electrical Stimulation (ESTIM) Guidance

Why: Functional confirmation (contraction) along motor points when voluntary activation is limited (e.g., severe dystonia, freezing). Particularly useful in deep or overlapping muscles.

Ultrasound (US) guidance

Why: Real-time visualization of depth, fascia, vessels, and adjacent structures enhances precision and reduces complications, such as dysphagia during neck procedures (Hong et al., 2012; Kaymak et al., 2018). It also assists in targeting the iliopsoas and external oblique muscles in cases of camptocormia (Von Coelln et al., 2008; Wijemanne & Jimenez-Shahed, 2014).

Best practice:

Mixed Guidance in Parkinson’s Disease (EMG/ESTIM + US)

Combine functional confirmation with anatomical visualization for complex areas such as the deep neck, paraspinals, and pelvic/hip flexors. Under various conditions, guidance improves accuracy, efficacy, and safety compared to manual placement alone (Comella et al., 1992; Speelman & Brans, 1995; Schnitzler et al., 2012; Grigoriu et al., 2015).

Why Mixed Guidance Matters

In Parkinson’s disease (PD), combined guidance—using electromyography (EMG) or electrical stimulation (ESTIM) alongside ultrasound (US)—provides distinct benefits in identifying, targeting, and treating complex motor issues such as resting tremor, dystonia, rigidity-related contracture, and postural deformities. These abnormalities often involve deep, overlapping, or small muscles with variable activation patterns, making single-modality localization less reliable.

Mixed guidance combines real-time anatomical imaging (US) with functional confirmation of pathological activity (EMG/ESTIM). This method enhances injection accuracy, improves toxin distribution, and reduces adverse events—especially in the neck, axial, and limb areas, where incorrect placement can cause dysphagia, weakness, or a suboptimal response.

Clinical Rationale

  • Dynamic motor signatures: PD tremor and dystonia can vary with posture, emotion, or task, making fixed anatomical targeting inadequate. EMG aids in confirming the active muscle amidst these changing patterns.
  • Altered muscle architecture: Chronic rigidity, postural deformities (e.g., camptocormia), and previous therapy can alter landmarks. Ultrasound helps accurately identify muscle planes and avoid neurovascular structures.
  • Complex regions: Mixed guidance is especially helpful for deep neck muscles (SCM, longus colli, scalenes), paraspinals, hip flexors, and upper-limb tremor clusters, where EMG confirms active motor units and ultrasound outlines safe paths.

Evidence and Outcomes

Studies have shown that instrumented guidance improves BoNT outcomes in focal dystonia and spasticity (Grigoriu et al., 2015), and mixed guidance extends these benefits to PD applications. Clinical reports demonstrate increased accuracy, fewer side effects, and better functional results when both modalities are used together.

Practical Application in PD

  • Cervical dystonia: Use EMG to confirm an overactive SCM or splenius; apply ultrasound to visualize depth and avoid nearby vascular or airway structures.
  • Camptocormia: Use EMG to identify active iliopsoas and external oblique muscles with US to ensure safe deep-muscle targeting.
  • Upper limb tremor/dystonia: EMG detects co-contraction or rhythmic discharges; US defines the spatial relationship of flexors and extensors to neurovascular bundles.
  • Freezing of gait (FOG): Mixed guidance facilitates precise injection of gastrocnemius–soleus complexes, aligning clinical outcomes with objective gait measurements.

Key Takeaway

Mixed guidance in PD enhances precision, safety, and therapeutic outcomes by integrating anatomical and physiological data during BoNT delivery. It is particularly advantageous in complex, multifocal, or posture-dependent motor cases and should be regarded as standard practice for clinicians managing advanced or atypical PD.

Practical patterns (adapt to patient goals)

  • ALO/Blepharospasm: Pretarsal/lateral orbicularis oculi; non-guided or ultrasound if anatomy is altered (Goldstein & Cogan, 1965; Yoon et al., 2005).Bruxism/Jaw tremor: Masseter ± temporalis; consider EMG to minimize unwanted diffusion and preserve bite force (Lee et al., 2010; Shim et al., 2014; Ondo et al., 2018; Schneider et al., 2006).
  • Cervical dystonia: Tailor to pattern (SCM, splenius, levator, scalene, semispinalis). EMG ± US enhances placement; monitor for dysphagia (Simpson et al., 2016; Kaymak et al., 2018; Comella et al., 1992).
  • Upper-limb tremor/dystonia: Flexors and extensors, pronator teres, biceps; customizable with EMG (± kinematics if available) (Jankovic & Schwartz, 1991; Brin et al., 2001; Rahimi et al., 2015; Mittal et al., 2017).
  • Camptocormia: Iliopsoas or external oblique assessed under US (± EMG) with functional goals (Von Coelln et al., 2008; Wijemanne & Jimenez-Shahed, 2014).
  • FOG: Calf (gastrocnemius–soleus) patterns are still under investigation; use EMG/US and objective gait metrics (Fernandez et al., 2004; Vaštík et al., 2016).

Counselling, tracking, and integration

  • Define functional goals (writing, eating, dressing, sleep, pain, head posture, gait).
  • Track outcomes with validated scales and objective tasks (e.g., handwriting spirals, dystonia scales, gait metrics).
  • Titrate thoughtfully—dose, targets, and intervals evolve; anticipate dysphagia with neck work and transient weakness with hand targets (Simpson et al., 2016; Colosimo et al., 2019).
  • Integrate rehab (task-specific training, posture/gait therapy) to extend gains (Tassorelli et al., 2006).

References (works cited in this article)

  • Anandan, C., & Jankovic, J. (2021). Botulinum toxin in movement disorders: An update. Toxins, 13(1), 42.
  • Berardelli, A., Rothwell, J. C., Thompson, P. D., & Hallett, M. (2001). Pathophysiology of bradykinesia in Parkinson’s disease. Brain, 124(11), 2131–2146.
  • Brin, M. F., Lyons, K. E., Doucette, J., et al. (2001). A randomized, double-masked, controlled trial of botulinum toxin type A in essential hand tremor. Neurology, 56, 1523–1528.
  • Colosimo, C., Charles, D., Misra, V. P., et al. (2019). Long-term patient satisfaction with BoNT-A in cervical dystonia. Journal of Neurology, 266, 3038–3046.
  • Comella, C. L., Buchman, A. S., Tanner, C. M., Brown-Toms, N. C., & Goetz, C. G. (1992). BoNT with EMG assistance for spasmodic torticollis. Neurology, 42, 878–882.
  • Fernandez, H. H., Lannon, M. C., Trieschmann, M. E., & Friedman, J. H. (2004). BoNT-B for freezing of gait in PD. Medical Science Monitor, 10, 282–285.
  • Gelb, D. J., Oliver, E., & Gilman, S. (1999). Diagnostic criteria for Parkinson disease. Archives of Neurology, 56, 33–39.
  • Goldstein, J. E., & Cogan, D. G. (1965). Apraxia of lid opening. Archives of Ophthalmology, 73, 155–159.
  • Grigoriu, A. I., Dinomais, M., Rémy-Néris, O., & Brochard, S. (2015). Impact of injection-guiding techniques for BoNT in spasticity/dystonia: Systematic review. Archives of Physical Medicine and Rehabilitation, 96(11), 2067–2078.e1.
  • Hong, J. S., Sathe, G. G., Niyonkuru, C., & Munin, M. C. (2012). Eliminating dysphagia using US guidance in cervical dystonia. Muscle & Nerve, 46, 535–539.
  • Jankovic, J., & Schwartz, K. (1991). BoNT treatment of tremors. Neurology, 41, 1185–1188.
  • Jankovic, J., Schwartz, K., Clemence, W., et al. (1996). RCT of BoNT-A in essential hand tremor. Movement Disorders, 11, 250–256.
  • Kaymak, B., Kara, M., Gürçay, E., & Özçakar, L. (2018). Sonographic guide for neck muscles in cervical dystonia. PM&R, 29, 105–123.
  • Kim, S. D., Yiannikas, C., Mahant, N., et al. (2014). BoNT for proximal upper-limb tremor. Movement Disorders, 29, 835–838.
  • Kouli, A., Torsney, K. M., & Kuan, W. L. (2018). PD etiology, neuropathology, pathogenesis. In Parkinson’s Disease: Pathogenesis and Clinical Aspects. Codon Publications.
  • Krack, P., Batir, A., Van Blercom, N., et al. (2003). Five-year STN-DBS follow-up in advanced PD. New England Journal of Medicine, 349, 1925–1934.
  • Lang, A. E., & Lozano, A. M. (1998). Parkinson’s disease (Part 1). New England Journal of Medicine, 339, 1044–1053.
  • Lee, S. J., McCall, W. D., Kim, Y. K., et al. (2010). BoNT for nocturnal bruxism: RCT. American Journal of Physical Medicine & Rehabilitation, 89, 16–23.
  • Marras, C., & Tanner, C. M. (2004). Epidemiology of PD. In Movement Disorders: Neurologic Principles and Practice (2nd ed.). McGraw-Hill.
  • Mittal, S. O., Machado, D., Richardson, D., et al. (2017). BoNT for PD tremor: RCT with customized approach. Mayo Clinic Proceedings, 92, 1359–1367.
  • Mittal, S. O., Lenka, A., & Jankovic, J. (2019). BoNT for tremor: Update. Parkinsonism & Related Disorders, 63, 31–41.
  • Ondo, W. G., Simmons, J. H., Shahid, M. H., et al. (2018). OnabotulinumtoxinA for sleep bruxism. Neurology, 90, e559–e564.
  • Parkinson, J. (1817). An essay on the shaking palsy. London: Sherwood, Neely, & Jones.
  • Rahimi, F., Samotus, O., Lee, J., & Jog, M. (2015). IncobotulinumtoxinA for PD upper-limb tremor using sensor-based patterns. Tremor and Other Hyperkinetic Movements, 2015, 1–13.
  • Schneider, S. A., Edwards, M. J., Cordivari, C., et al. (2006). BoNT-A for jaw tremor in PD. Movement Disorders, 21, 1722–1724.
  • Schnitzler, A., Roche, N., Denormandie, P., et al. (2012). Manual needle placement accuracy. Muscle & Nerve, 46, 531–534.
  • Scott, R. M., Brody, J. A., Schwab, R. S., & Cooper, I. S. (1970). Progression of unilateral tremor/rigidity in PD. Neurology, 20, 710.
  • Simpson, D. M., Hallett, M., Ashman, E. J., et al. (2016). AAN practice guideline update: BoNT in blepharospasm, cervical dystonia, adult spasticity, headache. Neurology, 86, 1818–1826.
  • Speelman, J. D., & Brans, J. W. (1995). Is EMG guidance necessary in cervical dystonia? Movement Disorders, 10(6), 802.
  • van der Heeden, J. F., Marinus, J., Martinez-Martin, P., et al. (2016). Postural instability/gait and PD prognosis. Neurology, 86, 2243–2250.
  • Vaštík, M., Hok, P., Hluštík, P., et al. (2016). fMRI reflections of BoNT for FOG in PD. Neuroendocrinology Letters, 37, 147–153.
  • Von Coelln, R., Raible, A., Gasser, T., & Asmus, F. (2008). US-guided iliopsoas injection for camptocormia. Movement Disorders, 23, 889–892.
  • Wijemanne, S., & Jimenez-Shahed, J. (2014). External oblique BoNT for camptocormia. Parkinsonism & Related Disorders, 20, 1106–1107.
  • Yoon, W. T., Chung, E. J., Lee, S. H., et al. (2005). Blepharospasm and ALO in parkinsonism. Journal of Clinical Neurology, 1, 159–165.
  • Yun, J. Y., Kim, J. W., Kim, H. T., et al. (2015). Dysport vs. Botox (2.5:1) in cervical dystonia. Movement Disorders, 30, 206–213.

Recommended Reading

  • Adler, C. H., et al. (2004). BoNT-A for voice tremor. Archives of Neurology, 61, 1416–1420.
  • Benecke, R., et al. (2005). IncobotulinumtoxinA (complexing-protein-free) in CD. Neurology, 64, 1949–1951.
  • Bertram, K., Sirisena, D., Cowey, M., et al. (2013). BoNT in primary orthostatic tremor. Journal of Clinical Neuroscience, 20, 1503–1505.
  • Costa, J., et al. (2004/2005/2017). Cochrane reviews on BoNT-A/B in cervical dystonia.
  • Delnooz, C. C. S., et al. (2013). fMRI network changes in CD with BoNT. PLoS ONE, 8, e62877.
  • Fietzek, U. M., et al. (2009). Goal attainment in camptocormia after BoNT. Movement Disorders, 24, 2027–2028.
  • Gracies, J.-M., et al. (2009). Endplate targeting in spasticity. Archives of PM&R, 90, 9–16.
  • Jinnah, H. A., et al. (2016/2018). Causes of non-response and discontinuation in CD. Journal of Neurology; Toxicon.
  • Kaymak, B., et al. (2018). Sonographic neck injection atlas. PM&R, 29, 105–123.
  • Pacchetti, C., et al. (2000). BoNT for functional disability in essential tremor. Neurol. Sci., 21, 349–353.
  • Pahwa, R., et al. (1995). BoNT for essential head tremor. Neurology, 45, 822–824.
  • Tassorelli, C., et al. (2006). BoNT + neuromotor rehab in CD. Movement Disorders, 21, 2240–2243.
  • Truong, D., et al. (2005/2010). US RCT and long-term safety of Dysport in CD. Movement Disorders; Parkinsonism & Related Disorders.

 Explore!

  1. Parkinson’s Disease Overview (NINDS); Learn more about Parkinson’s disease pathology and progression.

https://www.ninds.nih.gov/health-information/disorders/parkinsons-disease

  1. Botulinum Toxin in Movement Disorders: An Update (Anandan & Jankovic, 2021); Review evidence-based therapeutic applications of botulinum neurotoxin

https://pubmed.ncbi.nlm.nih.gov/33430071/

  1. Ultrasound Guidance in Neuromuscular Medicine (Frontiers in Neurology); Explore ultrasound-guided injection techniques for precision and safety

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6522931/

  1. Impact of Injection-Guiding Techniques on BoNT Efficacy (Grigoriu et al., 2015); See how EMG and ultrasound guidance improve botulinum injection outcomes

https://pubmed.ncbi.nlm.nih.gov/25982240/

  1. American Academy of Neurology – BoNT Clinical Guidelines; Review professional guidelines for botulinum neurotoxin therapy

https://www.aan.com/Guidelines/home/GetGuidelineContent/880

  1. Myoguide Academy – Clinical Education Series (Intronix Technologies); Access clinician education on guided neuromodulator injection techniques

https://www.intronixtech.com/myoguide-academy/

  1. Clinical Trials on BoNT and Parkinson’s Disease (NIH ClinicalTrials.gov); Explore ongoing research on botulinum toxin therapies in PD

https://clinicaltrials.gov/ct2/results?cond=Parkinson+Disease&term=botulinum+toxin

8. Myoguide Academy – Parkinson’s Disease (Intronix Technologies)

Access clinician education on Parkinson’s Disease with this FREE COURSE, available on the Myoguide Academy!

Parkinson’s Disease