RESUMO
Background: Atlas is the first cervical vertebra. Sometimes there is partial or complete fusion of atlas with basal part of the occipital bone known as assimilation of atlas or atlanto-occipital fusion. It is normally congenital. It may be associated with the constriction of foramen magnum which may compress the spinal cord or brain stem. Methods: The 1000 human dry skulls were selected from the anthropology museum of department of anatomy, GSVM medical college, Kanpur. The age and sex of the skulls were not taken into consideration. The skulls were examined for the bony union between the atlas and skull and other variations in assimilated atlas. Results: Fused atlas with skull was seen in 20 skulls (2.0%). Partial fusion of anterior arch of atlas with the occipital bone was seen in 1 specimen (5%) and in 10% it was found complete fusion. In 10% skulls the posterior arch fused with the occipital bone. Bilateral fusion of transverse process with occipital bone was noted in 2 (10%) specimen. The incomplete foramen transversarium was found in 1 skull (5%) {bilateral} and in 2 skulls (10%), the transverse process was noted without the foramen transversarium {bilateral}. Conclusion: Out of 1000 examined skulls, fusion of atlas with the occipital bone was noted in 20 skulls (2%). The knowledge of incidence of assimilation of atlas and its variations may be helpful for the embryologist, neurosurgeons and orthopedic surgeons.
RESUMO
Background: Suprascapular notch (SSN) is present towards the medial end of superior border of scapula. The morphometric variations of the SSN have been identified. The suprascapular nerve compression is commonly noted at the site of SSN. Methods: The study was carried out in the department of anatomy, SRMS-IMS medical college, Bareilly and SGRRIM-HS Dehradun. The 120 dried scapulae were randomly selected. The age, sex and race of the scapulae were not known. The scapulae were observed carefully for the different shapes of the suprascapular notch. The various dimensions of suprascapular notch were taken by using a digital vernior caliper. Results: In the present study six types of SSN were noted based on the description by Rengachary SS. et al.22 Type I (15.83%); type II (41.66%); type III (25.00%); type iv (12.50%); type v (1.67%) and type VI (3.33%). We also classified the SSN based on the description by M. Polguj et al. 2011,28 the frequencies were: type I (MVD>STD), 20%; type II (MVD=STD=MTD), 3.33%; type III (STD >MVD), 55.83%; type IV (bony foramen), 3.33% and type V (Without a discrete notch), 17.5%. Conclusion: The suprascapular neuropathy may occur at the various anatomical locations of its course and has a variety of causes. Our study is important for clinician because the narrow SSN increase the risk of suprascapular entrapment neuropathy. So the knowledge of these variations should be kept in the mind of clinicians in the diagnosis and treatment of suprascapular neuropathies.