[What would you do with an adult patient who consults due to head muscle weakness and has dropped head?].

The dropped head syndrome, whether due to muscle weakness, rigidity, or ankylosis, is not uncommon in the elderly. It is characterised by a "chin-on-chest" reducible kyphosis, which is secondary to head muscle debility. It may be associated with a neuromuscular group of diseases such as polymyositis, chronic Inflammatory demyelinating polyneuropathy, myasthenia gravis, amyotrophic lateral sclerosis, and inclusion-body myositis. Some cases associated with hypothyroidism and hyperparathyroidism have also been described. Prognosis without treatment is poor. Therefore, familiarity with this condition, together with a complete anamnesis and physical examination, should lead us to the clinical suspicion and selection of the appropriate complementary tests. In this article, a case of dropped head syndrome is reported, as well as an algorithm for its diagnosis.