Salih Sayhan

The importance of the greater occipital nerve in the occipital and the suboccipital region for nerve blockade and surgical approaches – An anatomic study on cadavers

OBJECTIVE Greater occipital nerve (GON) blockade is an effective method for treatment of occipital neuralgias. Occipital neuralgia or neuropraxis of this region may be seen particularly as a result of compression of the GON. This study shows the relationship between the GON and its external bone landmarks, in order to prevent complications and to perform nerve blockades safely. The study also defines the points where the GON pierces the semispinalis capitis (SSC) and the trapezius, and where the GON passes the obliquus capitis inferior (OCI), and identifies bone landmarks for places where the GON may be entrapped. MATERIALS AND METHODS In the laboratories of Dokuz Eylül University, Faculty of Medicine Department of Anatomy, 12 GONs belonging to male adult cadavers fixed in formaldehyde were dissected. Colored silicone was injected to all cadavers and then microdissections were performed under a dissection microscope. The lesser occipital nerve, the GON, the greater auricular nerve, and the occipital artery (OA) were dissected. All measurements were made with a 0.1mm sensitive calipometer. RESULTS The GONs diameter at the point where the GON pierces the SSC was found to be 2.5±0.3 mm. The distance between the point where the GON pierces the SSC and the external occipital protuberance (EOP) was 53.6±5.0 mm. The distance between this point and the midline was 9.0±1.9 mm, the distance between this point and the intermastoid line was 11.5±3.9 mm and the distance between this point and the mastoid process was 65.5±5.9 mm. The distance between the midline and the point where the GON pierces the aponeurosis of trapezius (AT) was 47.9±8.0 mm, the distance between this point and the EOP was 15.1±7.0 mm, the distance between this point and the intermastoid line was 17.1±2.8 mm, and the distance between this point and the mastoid process was 59.4±2.3 mm. We measured the distance between the OA and the intermastoid line to be 8.5±6.1 mm vertically and 32.3±3.9 mm horizontally to the midline. CONCLUSION In this study, we define the GONs route in the suboccipital and the occipital region where the nerve pierces the SSC and the AT and where blockade or surgery can be performed. These data will help the surgeon and clinician to avoid complications in this region.

Langerhans cell histiocytosis of the cervical spine in an adult: a case report.

We present a case of a 47-year-old-woman with a complaint of cervical pain with paresthetic appearance on her left arm. She was treated with analgetics. Further radiological evaluation because of the persistent pain revealed an osteolytic destruction of the fourth cervical vertebra. The patient underwent anterior cervical corpectomy with total excision of the tumor. Stabilization of the cervical spine was performed. Histology confirmed the diagnosis of Langerhans cell histiocytosis (LCH) of the cervical spine. This case report presents the histopathological evaluation, diagnostic work-up and the treatment procedures because of rarity of cervical spinal LCH cases in the literature.

Morphometric evaluation of the uncinate process and its importance in surgical approaches to the cervical spine: a cadaveric study.

INTRODUCTION The uncinate process (UP) has an important role because of its relationship with the vertebral artery and spinal roots. Degenerative diseases cause osteophyte formation on the UP, leading to radiculopathy, myelopathy and vertebral vascular insufficiency, which may require surgical management. This study aimed to evaluate the morphometry of this region to shed light on the anatomy of the UP. METHODS Morphometric data was obtained from 13 male formaldehyde-fixed cadavers. Direct measurements were obtained using a metal caliper. Computed tomography (CT) morphometry was performed with the cadavers in the supine position. RESULTS Direct cadaveric measurements showed that the height of the UP increased from C3 (5.8 ± 1.0 mm) to C7 (6.6 ± 0.5 mm). On CT, the corresponding measurements were 5.9 ± 1.2 mm at C3 and 6.9 ± 0.6 mm at C7. The distance between the left and right apex of the UP from C3 to C7 also increased on both direct cadaveric and CT measurements (C3: 20.8 ± 1.0 mm and C7: 28.1 ± 2.4 mm vs. C3: 23.7 ± 3.4 mm and C7: 29.0 ± 3.0 mm, respectively). On CT, the distance between the UP and superior articular process at the C3 to C7 levels were 9.8 ± 1.7 mm, 7.9 ± 1.8 mm, 7.9 ± 1.6 mm, 7.8 ± 1.3 mm and 8.2 ± 1.7 mm, respectively. CONCLUSION Direct cadaveric and CT measurements of the UP are useful for preoperative evaluation of the cervical spine and may lead to better surgical outcomes.