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Updated: May 5, 2026

Fiber Connections of the Supplementary Motor Area Revisited: Methodology of Fiber Dissection, DTI, and Three Dimensional Documentation
Published on: May 23, 2017
Supplementary motor area syndrome and flexor synergy of the lower extremities
Ju Seok Ryu1, Min Ho Chun, Dae Sang You
1Department of Rehabilitation Medicine, CHA Bundang Medical Center, CHA University, Seongnam, Korea.
Abstract:
Clinical presentation of supplementary motor area (SMA) syndrome includes complete akinesia of the contralateral side of the body and mutism, with secondary recovery of neurologic deficit. Multi-joint coordination is frequently impaired following the development of a brain lesion and is generally restricted by abnormal patterns of muscle activation within the hemiparetic limb, clinically termed muscle synergies. However, no work to date has confirmed this observation with the aid of objective methods, such as gait analysis, and the development of reflex pattern has not been suggested as a possible cause. We describe two unusual cases of flexor synergy after tumor resection of SMA lesions.
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