BACKGROUND: Geniospasm is a rare and generally benign movement disorder of the chin yet with potentially debilitating complications. Due to its rarity, previous literature was limited to only case reports or series with critical knowledge gap on its natural history, prognosis, and management. We aimed to establish the natural history, prognosis, and treatment for geniospasm.
METHODS: A systematic review on case reports or series was performed with literature search on PubMed and Google Scholar, from inception through December 2021. The quality of the reports was assessed with low-quality articles excluded for analyses other than demographics.
RESULTS: Forty-one articles were included for demographic analysis (n = 489) while forty articles for other analyses (n = 451). There was only slight male preponderance of this disease in our cohort (Male:Female = 1.2:1) with 98.6% having family history of geniospasm, 68.1% having onset below 1 year of age, 91.4% having emotional triggers of the symptoms, 25.7% having geniospasm in sleep, 100% involving mentalis muscles, 4.9% involving muscles adjacent to mentalis, 55.2% having regular paroxysms (≥1/week, but brief in 56.3% of the cases) and only 11.1% having complications. The paroxysms reduced with age, but complete remission only happened in 9.9%. Females (p = 0.010) and those without geniospasm in sleep (p = 0.048) were associated with good outcome of the disease. Geniospasm was usually refractory to treatment except for regular botulinum toxin injections.
CONCLUSIONS: Generally, geniospasm improved with age but complete remission was rare. Considering our review limitations, our findings should be interpreted with caution. Future studies of higher evidence level are crucial.

Geniospasm is a rare genetic disorder characterized by paroxysmal rhythmic or irregular movements of the chin and lower lip due to repetitive contractions of the mentalis muscle. Pathophysiology is poorly understood, and optimal treatment has not been established.
Geniospasm was characterized in a series of patients after evaluation in our clinics, and a comprehensive review of all cases in the medical literature was performed.
We evaluated four patients (1 female) in four families with geniospasm, aged 4 months to 9 years. Bothersome symptoms were present in one patient, who was treated with regular injections of onabotulinumtoxinA, with complete resolution of symptoms and no adverse effects. 9 patients in the literature have had similar outcomes.
Limited data exist with regard to the effective treatment of geniospasm. Several treatments have been used historically, with variable outcomes. Our results, together with those of prior reported cases, demonstrate benefit of the use of botulinum toxin injections for management of this condition.

暂无摘要。