Botulinum toxin for Pisa syndrome: An MRI-, ultrasound- and electromyography-guided pilot study

Abstract

Introduction: Pisa syndrome is a disabling, medication-resistant, postural abnormality that may affect 7-10% of patients with Parkinson's disease. In this study, we sought to assess the efficacy of botulinum toxin injections in Parkinson's disease-associated Pisa syndrome using a Magnetic Resonance Imaging-, Ultrasonography-, and Electromyography-guided combined approach.

Methods: We conducted a pilot study to evaluate the efficacy of botulinum toxin type-A injection in paraspinal and non-paraspinal axial muscles after a Magnetic Resonance Imaging and ultrasound-guided electromyography evaluation. Inclusion criteria were Pisa syndrome, idiopathic Parkinson's disease, and stable dopaminergic medications. Exclusion criteria were previous treatment with botulinum toxin, history of major spine surgery, and severe orthopedic diseases. As primary endpoint, we measured the rate of patients improving by at least 5° in the lateral trunk flexion 2 months after therapy. Secondary endpoints were the extent of lateral trunk flexion improvement, and changes in PS-associated pain/discomfort, measured by the Visual Analogue Scale.

Results: Out the 15 patients initially enrolled, 13 completed the follow-up assessment, while 2 joined a rehabilitation program and were excluded from the analyses. The rate of responders was 84.6% (n = 11/13), with 40% average reduction in trunk bending. Pain/discomfort improved in all patients, with 52.2% amelioration at the Visual Analogue Scale. The procedure was well tolerated in all cases, without side effects or complications.

Conclusion: A combined imaging and EMG botulinum toxin approach to Pisa syndrome may yield a success rate greater than 80% in Parkinson's disease.

Keywords: Botulinum toxin; EMG; Parkinson's disease; Pisa syndrome; Posture.