Intrinsic Vertebral Markers for Spinal Level Localization in Anterior Cervical Spine Surgery: A Preliminary Report

Abstract

Study DesignProspective clinical study.PurposeTo observe the usefulness of anterior cervical osteophytes as intrinsic markers for spinal level localization (SLL) during sub-axial cervical spinal surgery via the anterior approach.Overview of LiteratureVarious landmarks, such as the mandibular angle, hyoid bone, thyroid cartilage, first cricoid ring, and C6 carotid tubercle, are used for gross cervical SLL; however, none are used during cervical spinal surgery via the anterior approach. We present our preliminary assessment of SLL over anterior vertebral surfaces (i.e., intrinsic markers) in 48 consecutive cases of anterior cervical spinal surgeries for the disc-osteophyte complex (DOC) in degenerative diseases and granulation or tumor tissue associated with infectious or neoplastic diseases, respectively, at an ill-equipped center.MethodsThis prospective study on patients undergoing anterior cervical surgery for various sub-axial cervical spinal pathologies aimed to evaluate the feasibility and accuracy of SLL via intraoperative palpation of disease-related morphological changes on anterior vertebral surfaces visible on preoperative midline sagittal T1/2-weighted magnetic resonance images.ResultsDuring a 3-year period, 48 patients (38 males,10 females; average age, 43.58 years) who underwent surgery via the anterior approach for various sub-axial cervical spinal pathologies, including degenerative disease (n= 42), tubercular infection (Pott's disease; n=3), traumatic prolapsed disc (n=2), and a metastatic lesion from thyroid carcinoma (n=1), comprised the study group. Intrinsic marker palpation yielded accurate SLL in 79% of patients (n=38). Among those with degenerative diseases (n=42), intrinsic marker palpation yielded accurate SLL in 76% of patients (n=32).ConclusionsIntrinsic marker palpation is an attractive potential adjunct for SLL during cervical spinal surgeries via the anterior approach in well-selected patients at ill-equipped centers (e.g., those found in developing countries). This technique may prove helpful when radiographic visualization is occasionally inadequate.

Treatment of Cervical Spine Fractures and Subluxations without the Use of Intraoperative Fluoroscopy in Resource-Limited Settings

“…Anterior approaches are commonly performed for traumatic cervical spine injuries. Although external landmarks can be used to estimate a general orientation along the cervical spine, fluoroscopy is usually used for intraoperative spinal level localization (SLL) 3 to avoid surgical treatment of the wrong spinal level. In most developing countries and especially in rural settings, the latter is usually unavailable.…”

“…The carotid (Chassaignac's) tubercle-the anterior projection of the transverse process of the sixth cervical vertebra, is a reliable anatomic landmark for the extrinsic and intrinsic SLL. [3][4][5] In our setting, in the absence of intraoperative radiographic localization equipment, we used the carotid tubercle for SLL since its position is constant and not altered with patient's position. To the best of our knowledge, this is the first study in sub-Sahara Africa evaluating the accuracy and reliability of the carotid tubercle as a landmark during surgery for traumatic cervical spine injury.…”