• Sudhir Kumar Srivastava, Rishi Anil Aggarwal, Pradip Sharad Nemade, and Sunil Krishna Bhosale.
• Seth G.S. Medical college and K.E.M Hospital.
• Spine J. 2015 Sep 24.

Background ContextThe options available for treatment of Irreducible Atlantoaxial Dislocation (IAAD) with basilar invagination are odontoidectomy, posterior decompression, posterior atlanto-axial joint distraction. In 2006 Wang et al described that most IAAD can be reduced following anterior release of contracted soft tissues. Anterior release may be done by transoral (TO) or retropharyngeal (RP) approach. Posterior instrumented fusion provides stability and helps in achieving further reduction.PurposeTo study the neurological and radiological outcome following treatment of basilar invagination associated with irreducible atlantoaxial dislocation (IAAD) by anterior release and posterior instrumented fusion.Study DesignRetrospective Case Series PATIENT SAMPLE: 19 OUTCOME MEASURE: Patients were assessed for neurologic recovery by Benzel's modified Japanese Orthopaedic Association (mJOA) score and radiologically by assessing reduction on lateral radiographs and comparing clivus-canal angle on pre-op & post-op CT scan.Methods19 consecutive patients with IAAD were surgically treated. Anterior release was done via TO approach in 12 patients and RP approach in 7. Following anterior release all patients underwent posterior instrumented fusion.ResultsStudy included 15 males and 4 females with mean follow-up of 18 months. Pathology included occipitalisation of atlas in 16 patients, os odontoideum in 2 and missing posterior elements of axis in 1. All patients had cervical myelopathy. Occipitocervical fixation was done in 18 patients and C1-2 trans-articular screw fixation in one. 15 patients had anatomic reduction while 4 had partial. The clivus-canal angle improved from a mean pre-op angle of 111.47(0) to mean post op angle of 142.84(0). The mJOA improved from pre-op mean mJOA of 12.89 to a post-op mean mJOA of 16.84. Fusion was achieved in all patients. Maceration of posterior wound was noted in 3 patients which healed by daily cleaning and dressing (C & D). Implant breakage on one side was noted in one patient at 3 months post op, however patient remained asymptomatic.ConclusionThis series reinforces the safety and efficacy of both trans-oral and retro-pharyngeal anterior release for reduction of Irreducible AAD. Posterior fixation helps in achieving further reduction and provides stability. Anterior release followed by instrumented posterior fusion is a safe and effective modality of treatment for irreducible AAD associated with basilar invagination.Copyright © 2015. Published by Elsevier Inc.

3 keywords...

hide…