Is immobilization adequate treatment of unstable burst fractures of the atlas? A case report with long-term follow-up evaluation.

The biomechanics and roentgenographic anatomy of the unstable burst fracture of the atlas are well known. A few reports in the literature depict a bony avulsion of the transverse ligament associated with this fracture. However, all patients were treated surgically, so the natural course of this injury is undocumented--in other words, it is not known if the bony avulsion will heal. This is a case report of a 38-year-old woman with burst fracture of the atlas associated with a bony avulsion of the transverse ligament treated nonsurgically. At follow-up examination three years later, the bony fragment had not healed, and atlantoaxial instability persisted. Nonsurgical treatment of this injury may have a role, but surgical stabilization will usually be required after the posterior arch heals.