{"id":"c0f9b9cd-bc89-4a0a-9f51-75b99221d4eb","slug":"a-modified-transcondylar-screw-to-accommodate-anatomical-skull-base-variations","title":"A modified transcondylar screw to accommodate anatomical skull base variations","authors":["R. F. Ghaly","A. Lissounov"],"abstract":"Background: Occipitocervical instability may be attributed to congenital, bony/ligamentous abnormalities, trauma, neoplasm, degenerative bone disease, and failed atlantoaxial fixation. Indications for occipitocervical fixation include the prevention of disabling pain, cranial nerve dysfunction, paralysis, or even sudden death. Methods: The screw trajectory for the modified transcondylar screw (mTCS) is optimally planned utilizing a three-dimensional skull reconstructed image. Results: The modified mTCS technique is helpful where there is a loss of bone, such as after prior suboccipital craniotomy and/or an inadequate occipital condyle. The new proposed technique is similar to the classical transcondylar screw placement but follows a deeper course along the bony lip of foramen magnum toward clivus from a dorsolateral approach. Conclusion: The modified mTCS technique allows for direct visualization and, therefore, helps to avoid damage to the hypoglossal nerve and lateral aspect of brain stem.","thumbnailUrl":"https://sni-digital-videos.s3.amazonaws.com/articles/c0f9b9cd-bc89-4a0a-9f51-75b99221d4eb/featured/hero-1782420996110.png","publishDate":"2017-06-05T00:00:00.000Z","doi":"10.4103/sni.sni_433_16","categories":["Skull Base","Technical Note"],"fullTextUrl":"http://surgicalneurologyint.com/wp-content/uploads/2017/06/8419/SNI-8-98.pdf"}