Foramen magnum compression in Coffin-Lowry syndrome: A case report.

Coffin-Lowry syndrome (CLS) is a rare genetic disorder inherited in an X-linked dominant pattern. Common manifestations include intellectual disability, growth retardation, dysmorphic facial features, and variable skeletal anomalies. Here we report a patient who first presented with episodes of apparent life-threatening events (ALTE) found to be caused by hydrocephalus and brainstem compression at the foramen magnum. Together with his small size, short limbs and fingers, and facial appearance, the narrowing of the foramen magnum lead to the initial clinical misdiagnosis of hypochondroplasia. Subsequent evaluation and testing lead to the correct diagnosis of CLS. This case demonstrates the variability in presentation of CLS, and that skeletal findings may be misleading in infancy. © 2017 Wiley Periodicals, Inc.

Long latency response in soleus muscle evoked by magnetic stimulation at the foramen magnum.

We performed magnetic stimulation at the level of foramen magnum in healthy subjects to evaluate the long latency response in lower limb muscle. Subjects assumed an upright stance and we recorded electromyographic activities in soleus muscle. A late response at the onset latency of approximately 40 ms was elicited. The late response wasn't induced in other lower limb muscles; anterior tibial muscle, quadriceps femoris muscle, and biceps femoris muscle. Additionally, magnetic stimulation to foot motor cortex, basal occiput and cervical nerve roots did not evoke the response with latency of 40 ms. These results reveal the late response in soleus muscle that has not been previously reported. We speculate that it is involved with the long-loop reflex.

Microscopic anatomy of the infraorbital canal, nerve, and foramen.

OBJECTIVE: We performed this study to investigate the morphologic and topographic anatomy, and variations of the infraorbital canal (IOC), infraorbital nerve (ION), and infraorbital foramen (IOF). STUDY DESIGN AND SETTING: This study was performed at the Anatomy Department of Ankara University School of Medicine between 1999 and 2000. The morphometry of these anatomic areas on cadaver heads were studied microscopically. The morphologic and topograpic anatomies of IOC, ION, and IOF were carried out microscopically with x 25 to x 40 magnification on 10 cadaver heads (20 sides). RESULTS: We found the shape of the IOF as oval in 30% (6 sides), round in 40% (8 sides), and semilunar in 30% (6 sides) of the cadaver heads. We detected the IOF as single in 90% (18 sides), double in 5% (1 side), and triple in 5% (1 side) of the cases. We determined a complete roof (we called it as "canal") in 50% of cases and groove plus canal in 50% of the heads. The mediolateral relationship of the vessels to the nerve while emerging from the IOF was investigated, and the artery was always found in a mediosuperior position and the vein was inferior to it. In all specimens, the ION was found to be consisting of 3 to 8 fascicles interwoven with the artery and the vein in the loose connective tissue sheath. CONCLUSION: A detailed knowledge of the anatomic morphometry of this area is necessary for a surgeon while performing maxillofacial surgery and regional block anesthesia. Anatomic variations on this area may take place and a surgeon must take this into consideration so as to increase the surgical success.

Arterial and neural relations at the posterior and lateral aspects of the medullo-spinal junction.

The authors report the results of a series of 59 microdissections of the region of the foramen magnum. These dissections were made under the strict conditions of a surgical approach using an operating microscope. The major anatomic structures of the medullo-spinal junction are arranged mainly at its lateral aspect. The customary surgical approaches to the posterior cranial fossa give ready access to the cerebello- and latero-medullary cisterns. The description of the neurovascular structures contained therein assumes a particular importance because of the relative frequency of lesions developing at this level. This study deals particularly with the vertebral a. (VA), the inferior posterior cerebellar a. (IPCA), the cranial nn. IX (glossopharyngeal n.), X (vagus n.), XIc and XIs (cranial and spinal accessory n.) and XII (hypoglossal n.). The anatomy of this posterior and lateral region is characterised by the contrast between the relatively uniform course of the VA and the variable course of the IPCA, a true guideline whose very irregular arrangement accounts for the diversity of its relations with the last four cranial nn.