Clinical features of Conus Medullaris syndrome include all of the following, except:
Plantar extensor
Absent knee and ankle jerks
Sacral anesthesia
Lower sacral and coccygeal involvement
In conus medullaris syndrome knee jerks are preserved while the ankle jerks are affected. It is an impoant feature differentiating it with cauda equina syndrome. Ref: Harrison's Principles of Internal Medicine, 16th Edition, Pages 2439-40; Neurology Oral Boards Review: A Concise and Systematic Approach to Clinical Practice By Eroboghene E. Ubogu, Page 46