The Cross-Sectional Area of Paraspinal Muscles Predicts the Efficacy of Deep Drain Stimulation for Camptocormia.

Background: Camptocormia, a disturbance of posture, is a well-described clinical feature of PD and other parkinsonian syndromes. Previous reports have shown that DBS of the subthalamic nucleus (STN) or globus pallidus internus is effective in treating camptocormia. However, the efficacy of DBS for camptocormia varies. Objective: To determine a clinical marker for selecting an appropriate therapy for camptocormia, a disabling manifestation of Parkinson's disease (PD) that has a variable response to systemic and local therapies. Methods: We obtained pre-operative lumbar magnetic resonance imaging of 14 consecutive PD patients with camptocormia who underwent subthalamic nucleus deep brain stimulation (STN-DBS) in this retrospective-designed study. Lumbar MRI was performed three to six months prior to the operation. We measured the cross-sectional area (CSA) and width of each participant's paraspinal muscles. Results: Four (28.6%) patients were effective (EF), five (35.7%) were partially effective (PE), and five (35.7%) were noneffective (NE) to STN-DBS. The lumbar paraspinal CSA and width were significantly larger in the EF group than in the PE and NE groups. Conclusions: The CSA of paraspinal muscles and erector spinae width can be good predictive markers for improving camptocormia in patients with PD after deep brain stimulation.