Conservative management of crowned dens syndrome and atlas posterior arch resection: Two successful experiences of individualized treatment

Crowned dens syndrome (CDS) is a rare crystal deposition disorder characterized by distinctive halo‑like or coronal calcification surrounding the odontoid process, primarily manifesting as neck pain and restricted mobility, occasionally accompanied by systemic inflammatory signs. The present report describes two cases of patients with this condition with the aim of elucidating the clinical spectrum and management of CDS. The first case involved a 72‑year‑old male patient who exhibited marked symptom relief following treatment with non‑steroidal anti‑inflammatory drugs and a brief corticosteroid regimen, with no recurrence noted over a 2‑year follow‑up period. The second case involved an 81‑year‑old male patient who developed severe cervical spinal cord compression due to a calcified pseudotumor posterior to the odontoid process, leading to debilitating neurological deficits. This patient underwent a posterior atlas arch resection with microscopy assistance, resulting in the marked alleviation of spinal cord compression symptoms and sustained improvement over 3 years of follow‑up. On the whole, the present report underscores the importance of recognizing CDS and highlights that isolated posterior arch resection may serve as an effective intervention for patients with associated high cervical myelopathy. Given the rarity of this condition, further investigations through additional case reports are warranted to confirm these findings.