2023 Volume 14 Issue 5 Pages 767-772
Introduction: Dropped head syndrome caused by Parkinson's disease (PD) has a reported occurrence of 0.4-6%, but the difference in INEM (isolated neck extensor myopathy) concerning epidemiology, spinal alignment, and clinical futures is unclear.
Methods: Among 168 patients with DHS (41 males, 127 females, average age 74.1 years), we analyzed the differences in clinical findings among patients with INEM-DHS developed due to degenerative changes, patients with PD-DHS diagnosed with PD, and patients with PS-DHS diagnosed with drug-induced Parkinsonism.
Results: There were 116 cases (69.0%) with INEM-DHS, 13 (7.7%) with PD-DHS, and 6 (3.6%) with PS-DHS in addition to others. Females outnumbered males in all three groups. PD-DHS and PS-DHS had lower age onset than INEM-DHS. Three patients (1.8%) were diagnosed with PD at the initial examination for DHS, 4 (2.3%) developed DHS within 1 year from the diagnosis of PD, and 6 (3.6%) developed DHS in ≥1 year. Sagittal spinal alignment presented kyphotic deformity in PD-DHS and PS-DHS.
Conclusions: The complication rate of Parkinson's disease in patients with DHS was 7.7%, and 1.8% of the DHS cases were diagnosed with PD as a result of dropped head. Compared with INDM-DHS, PD-DHS was characterized by severe cervical kyphosis, and the clinical symptoms at onset were also severe, such as difficulty in walking with a continuous forward gaze. The prognosis tends to be poor.
