Objective: This study aims to review the case of a patient with suspected corticobasal syndrome (CBS) who presented with upper limb clumsiness, and to discuss the challenges associated with the clinical diagnosis and treatment of CBS.
Background: Corticobasal degeneration (CBD) should be suspected in cases of asymmetric upper limb clumsiness accompanied by extrapyramidal symptoms. However, CBD is characterized by a wide variety of pathological changes, leading to the clinical use of the term corticobasal syndrome (CBS). In cases with CBD pathology, the diversity of clinical symptoms complicates the diagnostic process.
Method: We retrospectively reviewed the clinical symptoms and progression of 10 patients (5 males, 5 females) with symptoms indicative of CBS, specifically upper limb clumsiness, with an average age of onset of 73.8 ± 4.1 years. The clinical diagnoses were discussed based on the clinical course and diagnostic criteria.
Results: Five patients were diagnosed with CBS according to the revised Cambridge criteria. Two patients presented with symptoms resembling progressive supranuclear palsy, in addition to upper limb clumsiness and dystonia. The remaining three patients exhibited upper limb clumsiness and dystonia, consistent with CBS, but did not meet the revised Cambridge criteria due to the absence of cognitive dysfunction, including language impairment. These three cases were considered to align with the clinical research criteria for probable sporadic CBD according to the Armstrong criteria.
Conclusion: CBD, which primarily presents with movement disorder symptoms, is a clinical diagnosis established based on the diverse pathological findings. In contrast, cases with CBD pathology can exhibit a range of clinical symptoms, leading to the proposal of complex diagnostic criteria. The need for a more straightforward and practical clinical diagnostic guideline is evident for future clinical use.
To cite this abstract in AMA style:
J. Nunomura. Underlying Diseases in a Patient with Upper Limb Clumsiness Suspected of Corticobasal Degeneration [abstract]. Mov Disord. 2025; 40 (suppl 1). https://www.mdsabstracts.org/abstract/underlying-diseases-in-a-patient-with-upper-limb-clumsiness-suspected-of-corticobasal-degeneration/. Accessed October 6, 2026.« Back to 2025 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/underlying-diseases-in-a-patient-with-upper-limb-clumsiness-suspected-of-corticobasal-degeneration/