Since the spinal cord is an anatomically eloquent area in which neurological functions are concentrated, surgical treatment of cervical spine and spinal cord diseases can affect neurological functions. To ensure and improve surgical outcomes, it is necessary to examine surgical indications and specific surgical methods by thoroughly confirming the pathology. For this purpose, it is essential to understand the characteristics of the cervical spine: (1) the column supporting the body, (2) protection of the spinal cord, (3) unique architecture of intermittent arterial penetration, (4) 3-dimensional movement, and (5) age-related changes.

  The more complex the pathology, the more important it is to take a global perspective while paying attention to local conditions to avoid “seeing the forest for the trees.” Therefore, it is recommended that each case be evaluated from the perspective of the anatomical characteristics of the cervical spine and that a treatment plan be considered accordingly.

  This paper outlines the importance of understanding the pathogenesis of the cervical spine and cervical cord pathology based on the anatomical characteristics of reliable cervical spine surgeries.

  The lumbar spine is involved in locomotion. Lumbar degenerative diseases, such as lumbar disc herniation, lumbar spinal stenosis, and lumbar degenerative scoliosis/kyphosis, are caused by the degeneration of the bone, disc, ligament, facets, and other elements of the lumbar spine. History taking, neurological examination, and diagnostic imaging are key to correct diagnoses. Conservative treatments, such as lifestyle guidance and medication, are effective in many patients with lumbar degenerative diseases. In cases of severe symptoms or insufficient effects of conservative treatment, invasive treatment is used. Several relevant technological developments are discussed in this article. The posterior lumbar approach is used in most lumbar surgeries. Fusion surgery is needed in cases of instability or deformity correction. However, decompression surgery has been reconsidered from the viewpoint of surgical site infection, adjacent segment disease, and the medico-economic problems induced by fusion surgery.

  Background : Spinal dural arteriovenous fistulas (DAVFs) are rare and can cause gait and micturition disturbances as well as paresthesias of lower extremities. Misdiagnosis may result in poor clinical outcomes.

  Methods : Fifty patients treated at the Tokyo Metropolitan Neurological Hospital were retrospectively analyzed.

  Results : Forty patients (80%) initially received misdiagnosis. At the initial hospital, most patients who underwent thoracic MRI were diagnosed correctly as spinal DAVFs, whereas most patients who underwent lumbar MRI received misdiagnosis such as lumbar stenosis, although they showed thoracic myelopathy, epiconus syndrome, and conus medullaris syndrome. Patients with delayed diagnosis of spinal DAVFs resulted in high rates of additional disability.

  Conclusion : When common lumbar stenosis fails to explain the symptoms, the possibility of spinal DAVFs should be considered, and thoracic MRI should be performed to confirm the diagnosis.

  Schwannomas are the most frequently encountered spinal tumors and can occur at any spinal level. The consensus treatment strategy is to remove the tumor, decompress the spinal cord and nerve roots, and confirm the histology. Most of these tumors are localized in the intradural, extramedullary space and can be removed using a standard posterior approach. However, surgery needs to be planned carefully to preserve neurological function and avoid complications for tumors located anterior to the spinal cord, exhibit a large mass, or dumbbell-shaped.

  In this article, the surgical strategies for spinal schwannomas and their outcomes are discussed.

  Patients with adult growth hormone deficiency (AGHD) present with diverse clinical symptoms associated with impaired quality of life and an approximate 2-fold increase in mortality, as compared with the general population. As most acquired causes of AGHD are associated with neurosurgical disorders (e. g., hypothalamic and pituitary tumors, pituitary surgery, and cranial radiotherapy), an accurate diagnosis of severe AGHD in daily neurosurgical practice followed by hormone replacement therapy with daily or weekly recombinant human growth hormone (rhGH) injections is critical. To achieve this aim, AGHD should be suspected in patients with current or a history of intracranial disease, and a diagnosis of severe AGHD should be established with growth hormone (GH) stimulation testing. As patients who are diagnosed with AGHD after cranial surgery or radiotherapy may not be granted medical expense support for a designated intractable disease, preoperative GH stimulation testing is crucial to prove that the patient had AGHD before surgery or radiotherapy. For patients who have undergone surgery for craniopharyngioma or pituitary adenoma, outpatient follow-up (every 3-6 months) is recommended to monitor the GH secretion status. Understanding the characteristics of rhGH injections, including common adverse events, contraindications, and the need for dose titration, is crucial, and neurosurgeons should inform patients about the potential risks of tumor recurrence. Consensus among neurosurgeons for the treatment of AGHD is warranted, as are guidelines for collaboration among different specialties.

  Upper lumbar disc herniation generally presents with various symptoms, and microscopic surgery is difficult due to anatomical features. We retrospectively analyzed the clinical symptoms, neurological features, and chronological transition of surgical options in 67 patients who underwent surgical treatment at our center between January 2004 and March 2021. There were 18 upper lumbar disc herniations at L1/2 and 49 at L2/3. Most of the clinical symptoms were back pain and leg pain/numbness, which were distributed in the inguinal and anterior thigh regions, along with foot numbness. There was a tendency for bladder dysfunction in cases with upper lumbar disc herniations, as compared to lower herniations. The deep tendon reflexes were decreased at L2/3 ; however, in some cases, they were increased at L1/2. Microscopic discectomy was rarely performed at L1/2, whereas it was performed in approximately half of the cases at L2/3. In our center, endoscopic surgery was introduced in 2016 and condoliase injection treatment in 2019. Surgical options have changed over the past several years. Less invasive surgeries, such as endoscopic surgery and condoliase injection treatment, seem to be useful surgical options for upper lumbar disc herniation.

  Glossopharyngeal neuralgia is rare, and there are even fewer reports of its coexistence with trigeminal neuralgia. Vascular compression theory, wherein normal vessels are in contact with and compress the root entry zone (REZ), is the hypothesized cause of this pathology. According to this theory, the nerve sheath of the REZ thins out at its transition point from the brainstem, and the physical stimulation of this segment results in neuralgia. We describe a case in whom glossopharyngeal neuralgia was caused by a cyst at the cerebellopontine angle. In this rare case, concomitant glossopharyngeal and trigeminal neuralgia were caused by different mechanisms.