[Highlateral approach to the lesions around the upper cervical vertebrae and foramen magnum].

In the present paper, we describe the surgical techniques of high lateral cervical approach and its feasibility for the excision of tumors located in the ventral or lateral aspect of the upper cervical vertebrae and of the craniovertebral junction. The patient is positioned laterally on the operating table, but the operator's position and the skin incision are slightly altered depending on the location of the tumor. When the lesion is situated below C1, the ipsilateral shoulder is pulled down toward the back. The operator stands rostral to the head. The attachment of the sternocleidomastoid muscle to the mastoid is detached and reflected anteriorly through a retroauricular curved skin incision. The posterior cervical muscles such as the splenius capitis, longissimus capitis, semi-spinalis capitis are detached from the occipit and retracted posteriorly. At this point, the transverse process of C1 and the articular facet of the vertebrae of C2-C4 are identified by palpation. According to the tumor location, the muscles attached to the relevant transverse processes and facets are divided and reflected posteriorly. Through careful dissection, the cervical nerve roots and the vertebral artery are exposed. The root sleeves as well as thecal sac may be exposed by resecting the posterior two-thirds of the superior and inferior articular facets and the adjacent laminae of the vertebrae. In case the whole facet was removed, an iliac bone graft is placed between the remaining transverse processes and the laminae above and below for fixation.(ABSTRACT TRUNCATED AT 250 WORDS)