Purpose : Anterolateral cervical lesions adjacent to nerve roots or vertebral arteries are difficult to access by the usual anterior or posterior cervical approaches. Here we describe surgical techniques for the anterolateral approach for cervical lesions and report their usefulness.

  Methods : The surgical route of the anterolateral approach is via the space posterior to the jugular vein and anterior to the sternocleidomastoid muscle, aiming at the transverse process of the cervical spine. This approach was used in 21 patients, including 6 patients with craniocervical lesions and 15 patients with subaxial cervical lesions. The most frequent pathology was dumbbell type schwannoma in 7 patients.

  Results : All the lesions adjacent to the nerve root and vertebral artery could be removed. However, in 6 patients other approaches such as retromastoid or anterior or posterior cervical were combined to accomplish further removal of lesions that extended to other areas. There were no complications directly related to the surgical methods, except for delayed cervical instability, which required cervical fusion.

  Conclusion : The anterolateral approach was useful for cervical lesions adjacent to the nerve roots or vertebral arteries.

  Objective : Proximal-type cervical spondylotic amyotrophy (CSA) is a rare clinical condition characterized by focal disturbance of the C5-C6 ventral nerve roots and/or the spinal segment of C5-C6, especially at the site of the ventral horn. The purpose of this study was to investigate the effects of anterior decompression surgery on proximal-type CSA.

  Materials and Methods : We retrospectively analyzed the course of 14 patients (11 men, 3 women) with proximal-type CSA who underwent anterior decompression at Nipponbashi hospital between 2003 and 2011. Clinical presentation, characteristics of images, particularly concerning kyphosis and high-intensity area (HIA) on T2-weighted magnetic resonance images (MRI), surgical procedures, and improvement in manual muscle test (MMT) grade were reviewed. We also analyzed age-specific findings and the correlation between symptom duration and outcome.

  Results : The proportion of CSA in all cases of surgically treated cervical spondylosis was 3.4%. The mean age of patients was 63.1 years (range 43-76 years), and the mean symptom duration was 14.7 months. Twenty-nine percent of the patients suffered from pure motor disturbance. Preoperative MMT grade was significantly lower in 59-69 years old patients. The preoperative MMT grades were 3.5 (<59 years old), 1.4 (59-69 years old), and 3.4 (>70 years old). There was no correlation between symptom duration and period until improvement. HIA was observed in eight cases (57%). Among them, postoperative HIA resolved in two cases. The patients in the two cases were under 59 years old and HIA was not accompanied by kyphosis. In contrast, HIA remained in cases where the patients were over 59 years old and HIA was accompanied by kyphosis. The surgical outcome was satisfactory in all cases, including those with long symptom duration. Surgical procedures were C4-C6 corpectomy in cases with multisegmental HIA and disk hernia, C4/5 corpectomy in cases with C4/5 localized disk hernia and instability, C3/4 corpectomy in cases with C3/4 localized disk hernia, and C4/5 foraminotomy in cases with the C5 ventral root disturbance.

  Conclusion : It should be noted that same patients have no subjective symptoms despite muscle atrophy. Anterior decompression resulted in a good surgical outcome in all cases of proximal-type CSA. Since a certain amount of decompression of the ventral nerve roots and ventral horns is expected in an anterior approach, we recommend anterior decompression in proximal-type CSA.

  Bow hunter's syndrome, also known as rotational vertebral artery occlusion, is characterized by recurrent attacks of paroxysmal vertigo, nystagmus, and syncope induced by horizontal head rotation. Typically, rotation of the head may induce stenosis or occlusion of the vertebral artery in C1-2 level, leading to compromised blood flow in the territory of the vertebro-basilar artery.

  We report a rare case of bow hunter's syndrome, in which compression of the vertebral artery was evident at the C6 level where the dominant vertebral artery enters the C6 transverse foramen. We utilized an anterolateral approach to reach the anterior wall of the C6 transverse foramen and successfully decompressed the vertebral artery. Importantly, intraoperative indocyanine green (ICG) videoangiography provided real-time information regarding the patency of the vessel after surgical manipulation. Thus, it was useful for spine surgeons to confirm degree of decompression of the vertebral artery.

  This is one of the first reports of the application of ICG videoangiography during surgical treatment of bow hunter's syndrome.

  A 56 year-old man complained of sudden bilateral shoulder pain following Brown-Séquard syndrome without any remarkable trauma. Magnetic resonance imaging (MRI) showed that disc herniation intensely compressed the spinal cord, with a surrounding isointense halo of cerebrospinal fluid (CSF) on T1 and T2-weighted images at the C3/4 level. He presented to our emergency room with tetraparesis, and underwent anterior discectomy and fusion using a hydroxyapatite-triphosphate complex spacer and an anterior cervical plate. A defect in the posterior longitudinal ligament (PLL) was seen, but adhesion between the dura and PLL was not observed. After removal of a fragment of the herniated disc, clear CSF leakage was seen. Dural laceration was sealed with absorbable hemostat and fibrin glue. The outcome was satisfactory, and complete recovery was noted at the 6-month follow-up. There was no neurological change 5 years and 9 months after surgery.

  Intradural cervical disc herniation is relatively rare ; only 32 cases, including ours, have been reported. Definitive diagnosis of an intradural rupture of the herniated disc before surgery is difficult. Characteristic MRI findings may help to confirm diagnosis. The pathogenesis of intradural cervical disc herniation is not clear. We presume that bone fragments included in the herniated disc may play an important role in the pathogenesis, however further histopathological investigations are needed to substantiate the mechanism.

  Although anomalies of vertebral arteries (VAs), such as fenestration or elongation, are not rare, there are few symptomatic reports in which an anomalous VA directly compresses the spinal cord nerve root. Vertebral artery anomalies have been reported to cause a variety of symptoms including neck pain, upper limb pain, and occipital neuralgia. The embryological development of the vertebrobasilar system may explain this anatomical anomaly. Here, we report a case of neuralgia in the upper limb caused by bilateral anomalous VAs with compression of the upper cervical cord. A 55-year-old man complained of a sharp and stabbing pain in the left suboccipital region and left upper limb. Neurological findings on admission showed no definite abnormality. MRI showed a flow void signal that compressed and distorted the cross section of the spinal cord at the level of C1-2. A vertebral artery angiogram and 3D-CTA showed that the bilateral vertebral arteries had pierced the dura mater under the posterior arch of the atlas and that the left VA was duplicated after emerging from the C2 transverse foramen. Given these findings, we diagnosed the symptoms suffered as arising from the bilateral anomalous VAs. Surgical treatment included a suboccipital craniectomy, a C1 laminectomy, and transposition of the vertebral arteries. The spinal cord was surgically decompressed by retracting the VAs with Gore-Tex tape and anchoring them to the C1 posterior arch. Postoperatively, the pain was relieved markedly and has not recurred for one year. A review of the literature and our case suggest that symptoms are completely relieved when surgical treatment includes transposition of the anomalous vertebral arteries. We emphasize the effectiveness of direct appropriate treatment.