Otto Mennicke (1876-) and the first description of skull base anomalies causing cerebellar tonsillar ectopia: one of the first mentions of the Chiari I malformation.

INTRODUCTION: Although Hans Chiari made significant and meaningful contributions to our understanding and classification of hindbrain herniations, others have also contributed to this knowledge. One figure who has been lost to history is Otto Mennicke. Herein, we discuss his role in our understanding of tonsillar ectopia and his life and connection to Hans Chiari.

CONCLUSIONS: Our knowledge of what is now known as the Chiari malformations has been shaped by several clinicians including Otto Mennicke.