A combined approach for stabilization and endoscopic/ endonasal odontoid and clivus resection for treatment of basilar invagination

Background: Basilar invagination (BI) is a complex condition characterized by prolapse of the odontoid into the brain stem/upper cervical cord. This lesion is often associated with Chiari malformations, and rheumatoid arthritis (RA). Treatment options for BI typically include cervical traction, an isolated anterior transoral odontoidectomy, anterior endonasal odontoidectomy, an isolated posterior fusion, or combined anterior/ posterior surgical approach. Case Description: A 45-year-old female with a Chiari I malformation and RA underwent a combined posterior C0-C5 posterior decompression/fusion, followed by an anterior odontoidectomy (i.e. endoscopic/endonasal under neuronavigation). Postoperatively, the patient’s symptoms and neurological signs resolved. Conclusion: BI in was successfully managed with a combined posterior C0-C5 decompression/fusion followed by an anterior endoscopic/endonasal odontoidectomy performed under neuronavigation.

SURGICAL MANAGEMENT OF ODONTOID FRACTURES, AN INSTITUTIONAL EXPERIENCE.

Introduction- Odontoid fractures occur as a result of high impact trauma to the cervical spine. Hyperextension of the cervical spine is The most common mechanism of injury. Odontoid fractures occurs in 10 to 15% of all cervical spine fractures . Fracture of the odontoid process is classied into one of three types which are type I, type II, or type III fractures. Of all the types of odontoid fractures, type II is the most common and accounts for over 50% of all odontoid fractures . Materials and Methods- This is a prospective study conducted over 2 years in Neurosurgery Department, Andhra Medical College & King George Hospital, Visakhapatnam. Result: A total of 18 odontoid fractures were managed in the period of two years, out of which 2 were kept conservative and 16 were operated. Out of 16, 11were operated with odontoid screw and 2 underwent C1-C2 xation and 3 patients underwent Transoral Odontoidectomy with posterior occipito-cervical xation Conclusion: The treatment of odontoid fracture is complex and should be planned according to the type of odontoid fracture and neurological decit. Odontoid screw will sufce in patients with type II fracture with undisplaced fragments. Posterior C1-C2 xation is a better choice for complex odontoid fractures. Transoral odontoidectomy and occipito-cervical xation is reserved as the last option.

Intraoperative Computed Tomography Scanner-Guided Craniovertebral Junction Surgery in a Patient with an Occipitalized C1

Craniovertebral junction surgery is associated with unique difficulties. Type 2 odontoid fractures (Anderson and D Alonzo) have a great potential for nonunion and malunion. These fracture patients may require a circumferential decompression and fixation. The addition of intraoperative CT with neuronavigation greatly aids in craniovertebral junction surgery. We operated on a 59-year-old-male with a type 2 fracture with posterior subluxation of C1 anterior arch and a cranially displaced odontoid peg. First, a transoral odontoidectomy was performed followed by a craniocervical fixation. Occipital plates and C3–C4 lateral mass screws were used as C1 was discovered to be occipitalized intraoperatively and atlantoaxial facet joints could not be reduced as discovered by intraoperative CT resconstruction. Intraoperative CT scan was crucial to this circumferential decompression and fixation, allowed us to resect the odontoid peg safely and completely and to confirm adequate screw trajectory making this complex surgery easier for us and safer for the patient. The patient was discharged 4 months after admission with stable neurology. Intraoperative CT was fundamental to correct decision making.

Reconsideration of the transoral odontoidectomy in complex craniovertebral junction patients with irreducible anterior compression

Background Although the single-stage posterior realignment craniovertebral junction (CVJ) surgery could treat most of the basilar invagination (BI) and atlantoaxial dislocation (AAD), there are still some cases with incomplete decompression of the spinal cord, which remains a technique challenging situation. Methods Eleven patients were included with remained myelopathic symptoms after posterior correction due to incomplete decompression of the spinal cord. Transoral odontoidectomy assisted by image-guided navigation and intraoperative CT was performed. Clinical assessment and image measurements were performed preoperatively and at the most recent follow-up. Results Eleven patients were followed up for an average of 47 months. Symptoms were alleviated in 10 of 11 patients (90.9%). One patient died of an unknown reason 1 week after the transoral approach. The clinical and radiological parameters pre- and postoperatively were reported. Conclusion Transoral odontoidectomy as a salvage surgery is safe and effective for properly selected BI and AAD patients after inadequate indirect decompression from posterior distraction and fixation. Image-guided navigation and intraoperative CT can provide precise information and accurate localization during operation, thus enabling complete resection of the odontoid process and decompression of the spinal cord.

Navigated transoral odontoidectomy to treat congenital basilar invagination after failed posterior reduction and fusion

Transoral odontoidectomy is a traditional technique to treat congenital basilar invagination (BI) associated with atlantoaxial dislocation (AAD). Although posterior surgery has been a trend to treat most cases, there are still cases that need to be treated through a transoral approach. In addition, intraoperative modern image-guided navigation systems help identify any remnants of the dens and decrease the risk of vertebral artery injury. For symptomatic cases with a history of previous posterior fusion and severe osteoporosis, transoral odontoidectomy is preferred over a posterior-only approach. Our video demonstrates the surgical technique for transoral revision odontoidectomy to treat congenital basilar invagination associated with atlantoaxial dislocation after previous posterior craniovertebral junction surgery.The video can be found here: https://youtu.be/vzcAW8oLcZY