Spontaneous Fracture of the Atlas in a Patient with Pycnodysostosis and Mandibular Osteomyelitis - A Case Report

Rationale: Mandibular osteomyelitis is a common complication in pycnodysostosis; however, spontaneous atlas fracture has not been previously reported. Patient Concerns: Persistent mandibular pain, swelling, and purulent discharge following tooth extraction, along with recent cervical discomfort. Diagnosis: Left mandibular osteomyelitis and type 3 atlas (C1) fracture in a patient with a prior diagnosis of pycnodysostosis. Treatment: Cervical immobilisation with a Philadelphia collar for 8 weeks, sequestrectomy under local anaesthesia, irrigation, debridement and targeted antibiotics. Outcomes: Favorable progress with no signs of infection or cervical symptoms after 6 months, along with partial bone healing in the mandible and stabilization of the C1 fracture. Take-away Lessons: In patients with pycnodysostosis, maxillofacial procedures must include prior cervical evaluation. Vertebral fractures may occur without evident trauma and present with minimal symptoms, posing a high clinical risk if undetected.