Re‐Emergent Tongue and Jaw Tremor in Parkinson's Disease: A Case Series and a Literature Review

Background Parkinson's disease (PD) is characterized by various motor symptoms, with tremors being the most common symptom. This case series reports two sporadic cases of re‐emergent tremors involving the tongue in patients with PD, and discusses their clinical significance. Cases The first case involved a 74‐year‐old man with a 7‐year history of parkinsonism who developed a re‐emergent tongue tremor at 4–5 Hz, emerging approximately 3 seconds after tongue protrusion. The second case describes a 65‐year‐old woman with a 25‐year history of PD who exhibited a similar re‐emergent tongue and jaw tremor with 3‐s latency. Literature Review A literature review identified five previous case reports of re‐emergent tremors of the tongue and jaw lip in patients with PD. The tongue appears to be the most commonly involved site among the facial regions affected by re‐emergent tremors. The frequency and latency of tongue and jaw re‐emergent tremors were similar to those observed in upper limb tremors, suggesting a shared underlying mechanism. Conclusion This case series highlights the recognition of re‐emergent tremors in the facial regions as potential manifestations of PD, and emphasizes the need for more comprehensive and standardized assessment protocols for neurological examinations.