Objective: To evaluate the clinical efficacy and safety of muscle afferent block (MAB) for treating camptocormia in Parkinson’s disease (PD), focusing on objective postural angles and autonomic safety.
Background: Camptocormia is a disabling postural deformity in PD characterized by marked thoracolumbar flexion. Its pathophysiology likely involves dystonic mechanisms in trunk muscles. MAB, which reduces muscle spindle sensitivity via anesthetic and alcohol injections, is a potential treatment for focal dystonia. However, its effectiveness and safety—specifically regarding autonomic stability—in PD-related camptocormia remain unclear.
Method: We prospectively studied eight PD patients with camptocormia (n=8). A mixture of 0.5% lidocaine and absolute ethanol was injected bilaterally into the external oblique muscles under ultrasound guidance for 10 sessions. The primary outcome was the change in total camptocormia (TCC) angle (C7-L5-lateral malleolus) in a standing position. Autonomic safety was assessed using the head-up tilt (HUT) test to monitor systolic blood pressure (SBP) changes. Statistical analysis was performed via the Wilcoxon signed-rank test.
Results: The mean TCC angle significantly improved from 64.8±23.1 at baseline to 43.6±27.5 post-treatment (p=0.012). In the safety analysis, the HUT test showed no significant difference in SBP drop before and after MAB (p=0.425). No serious adverse events or permanent muscle weakness were observed, and all patients tolerated the repeated injections well.
Conclusion: Ultrasound-guided MAB targeting the external oblique muscles is an effective and safe intervention for camptocormia in PD. The stability of blood pressure suggests it is safe even in patients with autonomic concerns. MAB offers a promising, minimally invasive option for managing refractory postural symptoms in Parkinson’s disease.
To cite this abstract in AMA style:
S. Horie, K. Matsuura, K. Sakae, A. Shindo. Efficacy and Safety of Muscle Afferent Block for Camptocormia in Parkinson’s Disease [abstract]. Mov Disord. 2026; 41 (suppl 1). https://www.mdsabstracts.org/abstract/efficacy-and-safety-of-muscle-afferent-block-for-camptocormia-in-parkinsons-disease/. Accessed October 1, 2026.« Back to 2026 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/efficacy-and-safety-of-muscle-afferent-block-for-camptocormia-in-parkinsons-disease/