R. Choudhry

Facial vein terminating in the external jugular vein. An embryologic interpretation.

The external jugular v. (EJV) is increasingly being used for therapeutic procedures and monitoring by clinicians. In view of this clinical relevance, dissection was done on the head and neck regions in 40 adult cadavers of Indian origin to detect variations of the EJV. Though several patterns of tributaries were found, a facial v. (FV) of considerable size was observed coursing obliguely to join the EJV in the neck in four cases (5%). The distance of the junction of the FV and the EJV from the angle of the mandible ranged between 55 and 104 mm. This may represent a persistent communication of the primitive linguofacial v. with the secondarily developing EJV. This anastomotic channel is present for some time in the fetus but later undergoes retrogression. Its persistence in some individuals results in this variation.

Variation in shape of the lingula in the adult human mandible.

The lingulae of both sides of 165 dry adult human mandibles, 131 males and 34 females of Indian origin, were classified by their shape into 4 types: 1, triangular; 2, truncated; 3, nodular; and 4, assimilated. Triangular lingulae were found in 226 (68.5%) sides, truncated in 52 (15.8%), nodular in 36 (10.9%) and assimilated in 16 (4.8%) sides. Triangular lingulae were found bilaterally in 110, truncated in 23, nodular in 17 and assimilated in 7 mandibles. Of the remaining 8 mandibles with different appearances on the 2 sides, 6 had a combination of triangular and truncated and 2 had nodular and assimilated. The incidence of triangular and assimilated types in the male and female mandibles are almost equal. In the truncated type it was double in the male mandibles while the nodular type was a little less than double in the female mandibles.

Incidence and morphological study of zygomaticofacial and zygomatico-orbital foramina in dry adult human skulls: the non-metrical variants

Morphological diversity in the form of multiple zygomaticofacial (ZF) foramina was studied in 165 dry, unsexed adult human skulls. Zygomatic bones revealed variation in the number of foramina on their orbital and facial aspects. These were absent in 72 (21.8%) sides. A single ZF foramen was seen in 148 (44.9%) sides. Two ZF foramina were found in 92 (27.9%) sides, out of which 29 (8.8%) sides had one zygomatico-orbital (ZO) foramen, while 63 (19.1%) sides had two ZO foramina. Three ZF foramina, a relatively uncommon occurrence, were found in 17 (5.1%) sides, which included eight (2.4%) sides with one less and nine (2.7%) sides with the same number of ZO foramina. Four ZF foramina were seen in one (0.3%) side with three on the orbital aspect, a feature not reported before. The zygomatic nerve may be disrupted on elevating periorbita from the lateral wall during orbital surgery, and care should be taken to prevent injury to the nerve during the lateral orbitotomy approach to access intraorbital soft tissue tumors.

Morphological description of combined variation of distal attachments of fibulares in a foot

An interesting case of peculiarity of the distal attachment of the three fibular muscles is reported in the left foot of a male adult cadaver of Indian origin. The fibularis brevis, just inferior to the fibular malleolus, gave off an additional slender tendon anteromedial to its main tendon. This was attached to the dorsal digital expansion of the little toe while its main tendon was inserted to the customary bone. The tendon of fibularis longus on the plantar aspect just medial to the cuboid tunnel received a prominent slip of attachment of the tendon of tibialis posterior. The fibularis tertius had two parallel-running tendons attached to the bases of the fourth metatarsal and the fourth and fifth metatarsals respectively. The combined variation of the three fibulares in a single foot has not been reported previously. The more distal attachment of the fibularis brevis in this case is a regression in evolution. Weakness of both the fibularis brevis and fibularis longus is found in pes cavovarus. The former can be used as a rotational graft in soft tissue loss of the leg.

Morphologic and imaging studies of duplicate optic canals in dry adult human skulls

Three dry adult human skulls, two with bilateral and one with unilateral duplication of the optic canal were found. Their gross morphologic features were studied. Optic canals were separated by a septum of variable thickness dividing the posterior part of the canal into a large canal in the usual position and a smaller one inferior to it. The skull with unilateral duplication of the right side had a bony bar forming the carotico-clinoid canal. One of the skulls was disarticulated and its sphenoid had bilaterally duplicated optic canals divided by thin septa, both having a slit. Conventional radiography and CT scans for the optic canal were performed on two of these skulls but not on the disarticulated bone, and the imaging representations of these features were correlated with the anatomic findings on the dry skull.

Unusual facets on the acetabulum in dry adult human coxal bones A morphological and radiological study

Abstract A smooth facet was found antero-inferior to lunate surface of 48 acetabula, in a study conducted on 315 dry adult coxal bones, 26 of which (13 pairs) were of articulated pelves. Three different shapes of the facet were oval (56.3%), piriform (22.9%) and elongated (20.8%). The prevalence of the oval facet was higher in both sexes. In 37.5% bones it extended to superior ramus of pubis and in 62.5% it was limited within the acetabular margin. They were either discrete (58.3%) or continuous with the lunate surface (41.7%). The surface configuration was flat (29.2%), concave (43.7%) or grooved (27.1%). One male articulated pelvis showed a bilateral presentation. Measured along the long axis the size varied between 11 to 17 mm. The radiographs showed notching, antero-inferior to acetabular margin in grooved facets whereas concave and flat facets were seen as areas of rarefaction. It is postulated that this facet could be a consequence of a particular posture which results in traction of the ligaments attached to this area. This unusual feature has not been reported earlier.

Morphology of human suprarenal glands: a parameter for comparison

Forty suprarenal glands were studied, 20 being dissected from aborted fetuses of 9 to 36 weeks’ gestation and 20 obtained from human cadavers of ages 1 day to 60 years. All the specimens were from a Northern India population. The side and shape of each suprarenal gland was noted and documented. The length, breadth, thickness and volume of each gland were measured and tabulated in terms of age. The mean length, breadth and thickness in fetuses of 9–36 weeks were found to be 1.4 cm, 1 cm and 0.45 cm respectively. In the postnatal age group the measurements were 4.5 cm, 2.08 cm and 0.66 cm respectively. The commonest shape of the suprarenal glands on left side was semilunar but on the right side it was highly variable: triangular, tetrahedral, inverted Y or V shaped. On comparison of the gross measurements with available ultrasound and CT scan data it was found that both the length and thickness in the population studied were greater than reported in the literature. A knowledge of these variations is very important in diagnosis of abnormalities of the suprarenal gland, of which tumoral enlargement is rather common.

Os capitatotrapezoid: a case report

A case of fused capitate and trapezoid, the os capitatotrapezoid (OCT), was found in an articulated right hand of a male skeleton. Fusion was almost complete except for shallow grooves demarcating the line of fusion on the proximal and distal aspects. Radiology revealed a normal trabecular pattern and no joint cavity within these fused bones. The styloid process of the third metacarpal was absent.

Anatomical Description and Frequencies of Bony Projections on the Cerebral Aspect of the Petromastoid Part of the Temporal Bone in Dry Adult Human Skulls

A morphological peculiarity was observed in the form of bony projections on the upper part of the medial border of the groove for the sigmoid sulcus on the internal surface of the mastoid part of the temporal bones. In a study on 636 temporal regions of 318 dry unsexed adult human skulls of Indian origin, 101 (15.9%) temporal bones exhibited these elevations. These ranged from being inconspicuous tubercles to well-defined sharp spines. In 73 (72.3%) cases, a projection was present unilaterally, more commonly on the right side and in 28 (27.7%) it was bilateral. A subjective assessment of the size showed the projections to be small (70; 69.3%), medium (16; 15.8%) and large (15; 14.8%).

Unusual features associated with cranial openings of optic canal in dry adult human skulls

One hundred and eighty six dry adult human skulls (372 sides) were studied in order to reveal the presence of unusual features—such as recess, fissure and notch—in the cranial opening of the optic canal. Recess, an extension of the lateral wall, was found in 229 (61.5%) sides. Fissure, an irregular discontinuity above the lateral recess, was observed in 158 (42.4%) sides. Notch, a gap in the posterior-most limit of the roof, was seen in 66 (17.7%) sides. These were commonly seen bilaterally. The etiology of these was attributed to the development of the optic canal. During intrauterine life the optic canal is in the form of a large keyhole shaped foramen, which slowly transforms into the adult canal. A developmental arrest at an early stage may lead to the formation of recesses and fissures.