Important aspect of hypoglossal nerve injury following gunshot wound; Can the clivus has a role? A case report

Hypoglossal canal: an osteological and morphometric study on a collection of dried skulls in an Italian population: clinical implications

BACKGROUND

The hypoglossal canal is a dual bone canal at the cranial base near the occipital condyles. The filaments of the hypoglossal nerve pass through the canal. It also transmits the meningeal branch of the ascending pharyngeal artery, the venous plexus and meningeal branches of the hypoglossal nerve. The hypoglossal nerve innervates all the intrinsic and extrinsic muscles of the tongue except the palatoglossal and is fundamental in physiological functions as phonation and deglutition. A surgical approach to the canal requires knowledge of the main morphometric data by neurosurgeons.

METHODS

The present study was carried out on 50 adult dried skulls: 31 males: age range 18-85 years; 19 females: age range 26-79 years. The skulls came from the ''Leonetto Comparini'' Anatomical Museum. The skulls belonged to people from Siena (Italy) and its surroundings (1882-1932) and, therefore, of European ethnicity. The present study reports (a) the osteological variations in hypoglossal canal (b) the morphometry of hypoglossal canal and its relationship with occipital condyles. One skull had both the right and left hypoglossal canals occluded and, therefore, could not be evaluated. None of the skulls had undergone surgery.

RESULTS

We found a double canal in 16% of cases, unilaterally and bilaterally in 2% of cases. The mean length of the right and left hypoglossal canals was 8.46 mm. The mean diameter of the intracranial orifice and extracranial orifice of the right and left hypoglossal canals was 6.12 ± 1426 mm, and 6.39 ± 1495 mm. The mean distance from the intracranial end of the hypoglossal canal to the anterior and posterior ends of occipital condyles was 10,76 mm and 10,81 mm. The mean distance from the intracranial end of the hypoglossal canal to the inferior end of the occipital condyles was 7,65 mm.

CONCLUSIONS

The study on the hypoglossal canal adds new osteological and morphometric data to the previous literature, mostly based on studies conducted on different ethnic groups.The data presented is compatible with neuroradiological studies and it can be useful for radiologists and neurosurgeons in planning procedures such as transcondilar surgery. The last purpose of the study is to build an Italian anatomical data base of the dimensions of the hypoglossal canal in dried skulls..

Introducing a new possible predisposing risk factor for odontoid type 2 fractures after cervical trauma; Ponticulus posticus anomaly of C1 vertebra

OBJECTIVE

Ponticulus posticus is an anomaly of the atlas. Odontoid fracture type 2 fracture occurs by hyperflexion, hyperextension, lateral flexion, and a combination of these movements. The presence of Ponticulus Posticus anomaly may affect the occurrence of odontoid fractures of the C2 vertebra. In this study, the relationship between the presence of PP anomaly and occurring of the odontoid type 2 fracture was investigated.

PATIENTS AND METHODS

Cervical CTs of a total of 14 patients with odontoid type 2 fracture were retrospectively evaluated for PP, and compared with 13 patients with cervical trauma without odontoid type 2 fracture.

RESULTS

Ponticulus posticus anomaly was noted in 7 of 14 patients with odontoid type 2 fractures on the upper cervical CT; therefore, the prevalence was 50.%, but only 3 cases (23.07%) were seen in 13 patients of the control group. In binominal regression analysis showed that the presence of PP anomaly increases 12,075 times to occur odontoid type 2 fracture after cervical trauma.

CONCLUSION

Ponticulus posticus is often not recognized, but this study shows that ponticulus posticus is a risk factor for odontoid type 2 fracture after cervical trauma.

First histopathological bridging of the distance between Onuf's nucleus and substantia nigra after olfactory bulbectomy-new ideas about the urinary dysfunction in cerebral neurodegenerative disease: an experimental study

OBJECTIVES

Olfactory bulbectomy (OBX) in experimental studies induces neurochemical, neurodegenerative changes in various parts of the body. But no information is available about how OBX affects the spinal cord in rats. Our study aims to investigate this question.

METHODS

Twenty-eight male rats were used. The rats were divided into three groups: six as the control, six as the SHAM, and 16 as the study group in which OBX was performed. The animals were followed for 10 weeks. After decapitation of the animals, olfactory bulb (OB) volumes, the olfactory glomerulus (OG), and the neuron density of the ON (Onuf nucleus) per cubic centimeter at the L4-S4 level were examined histopathologically and analyzed stereologically.

RESULTS

The mean OB volume, remaining normal OG density, and degenerated neuron density (DND) of the ON was measured as 4.32 ± 0.21/mm³ , 1842 ± 114/mm³ , and 4 ± 1 /mm³ in the control (group I); 3.3 ± 0.14/mm³ , 1321 ± 114/mm³ , and 43 ± 8/mm³ in the SHAM (group II); and 1.672 ± 0.12/mm³ , 852 ± 93/mm³ , and 154 ± 11/mm³ in the study group (group III). There was a statistically significant difference between the SHAM and the study group (P < .05).

CONCLUSIONS

In this study, histopathological bridging between ON-related lower urinary tract symptoms (LUTS) and OBX was shown the first time. According to the findings, LUTS may be reversed by the protection of the affected spinal cord through the correction of olfaction impairment in neurodegenerative disease.