Bilateral arterial variation in the upper extremity--an anatomical case report

We report a case of bilateral arterial variation in the upper extremities of a male cadaver. In the left upper extremity, it was observed that the ulnar artery was arising from axillary artery. This ulnar artery was superficial throughout its course at the medial aspect of the arm and forearm. It was highly tortuous and did not have any branches either in the arm or forearm. It ended as the superficial palmar arch in the palm. However the brachial artery entered the cubital fossa and divided into radial and common interosseus arteries. In contrast, the right upper extremity was having normal brachial artery which was terminated into the ulnar and radial arteries at the cubital fossa. However, there was an accessory brachial artery present at the arm and ended at the cubital fossa. We believe that these anatomical variations are because of abnormal developmental vascular pattern in the region. In clinical practice, accurate knowledge of the arterial variations of upper extremity is of considerable importance in case of reparative surgeries and fracture management. They are of interest to the vascular and plastic surgeons.

Incomplete discoid lateral meniscus: a case report

The variations of lateral meniscus include pathologic entities which vary in size, shape and attachment. In this manuscript, we report a case of discoid lateral meniscus which was observed in an embalmed fetal cadaver. It was an incomplete variety of the discoid meniscus and observed on the right side knee. The clinical implication of this discoid meniscus has been emphasized along with the review of literature. The morphological and embryologic details of the discoid lateral menisci are discussed.

Bone morphometry

OBJECTIVES

To compare anatomical measurements with that of radiological measurements.

BACKGROUND

The radiological measurements are commonly used in clinical practice. It is well known that the anatomical measurements are more accurate than radiological. The comparison of anatomicoradiological measurements is not reported hitherto.

METHODS

One human adult cadaveric femur bone was used for the present study. It was measured both anatomically and radiologically.

RESULTS

In digital X- ray measurements, the length from the upper lip of fovea capitis to the most prominent part of greater trochanter was 87.2 mms, from the upper most part of greater trochanter to the isthmus it was 147.9 mms, mediolateral width of medullary cavity at the isthmus was 8.9 mms, the mediolateral width at the distal root of lesser trochanter was 18.5 mms, anteroposterior width of medullary cavity at the isthmus was 11.5 mms, the anteroposterior width at the distal root of lesser trochanter was 16.8 mms. The same measurements were 91.2 mms, 154.6 mms, 11.8 mms, 19.7 mms, 11.9 mms and 18.5 mms when taken anatomically using the digital vernier caliper.

CONCLUSION

The present study showed that in all the parameters measured the radiological values were slightly lesser than the anatomical values. Considering the variations in the values, the implants can be designed for a particular case in orthopedic surgery. We believe that this study adds an important reference in the scientific literature (Tab. 1, Fig. 2, Ref. 5).

Clinically oriented morphometric study of medial and lateral menisci of the knee joint in adult cadavers

PURPOSE

The objective was to analyze the peripheral and inner border lengths of the medial and lateral menisci and the distance between anterior and posterior horns.

MATERIALS AND METHODS

The menisci from 23 adult knee joints (46 menisci) of the formalin fixed cadaver lower limbs were used. The peripheral and inner borer lengths of the menisci were measured with a non elastic cotton thread and the distance between the horns were measured with the vernier caliper of 0.02 mm accuracy.

RESULTS

The mean peripheral lengths of the medial and lateral menisci were 99.06 +/- 11.21 and 90.25 +/- 9.36 mm respectively. The inner border lengths for the same were determined as 55.44 +/- 8.37 and 50.63 +/- 5.33 mm respectively. The distances between the anterior and posterior horns were 24.13 +/- 4.19 and 11.31 +/- 3.86 mm for the same. The peripheral length and inter horn distance of the medial meniscus was more than the lateral, the statistically significance was observed (*p<0.05). The other parameters obtained were statistically not significant.

CONCLUSION

The present study had determined some important anatomical data which may be of importance to the orthopaedic literature. The findings are also enlightening for the anthropologists and clinical anatomists.

Morphometric analysis of clavicle in nepalese population

BACKGROUND

Determining the sex of deceased is easy when a complete skeleton is available for examination. On the whole, the bones are heavier, larger and markings of muscular attachments are more pronounced in the male than in the female.

OBJECTIVE

The purpose of this study was attempted to evolve an easily applied formula to enable the assessment of sex in an unknown clavicles and to know about comparative differences between the right and left clavicles, from certain metrical parameters.

METHODS

The study was an observational, cross-sectional and descriptive in nature. The present study was conducted on 257 adult clavicles out of which, 135 were of the right side and 122 of left side. The maximum length of the clavicle (in mm) was taken.

RESULTS

The length of the right clavicles varies from 108 mm to 178 mm with an average of 143.21 mm ± 11.13 mm S.D. The length of the left clavicles varies from 111 mm to 181 mm with an average 145.53 mm ± 11.04 mm S.D. It has been observed that the left clavicle was longer than the right clavicle by 2.32 mm. There was no such single character which can determine the sex of all clavicles. Depending on the length alone, the sex can be decided in 13.33% male and 4.44% female right clavicles and 16.39% male and 9.83% female bones if the left clavicle is considered.

CONCLUSION

The left clavicle was longer than the right clavicle. The determination of sex from the clavicle has a great medico legal significance to the toxicologists. It also helps the anthropologists in their study of evolution of mankind and migration of races.

Foramina on the zygomatic bone: its clinical significance

AIM

To study the anatomy of zygomatico-orbital, zygomatico-facial and zygomatico temporal foramina in south Indian population.

MATERIALS AND METHODS

50 dry adult skulls of south Indian origin were studied. The number of ZO, ZF and ZT were recorded on each side. The distances of these foramina to the nearest palpable bony points, infero-lateral angle of the orbit and infra-orbital foramen were measured using Vernier's calipers.

RESULTS

Variable number of ZO and ZF foramina, ranging from 0 to 4 was seen. Single ZO foramen in 56% and 44%, double in 6% and 12%, absent in 38% and 44% on right and left sides were seen. Distance of ZO foramen from inferolateral angle of orbit was 9+2.51 mm and 7.8+1.74 mm on right and left side respectively. The mean distance from infraorbital foramen was 29.93+2.76 mm and 30.19+ 3.52 mm on right and left side respectively. Single ZF foramen in 40% and 42%, double in 10% and 8%, 3 in 4% on right side and 4 in 2% on left sides were seen. In the remaining 46% and 48% of bones, the ZF foramen was absent. Mean distance from inferolateral angle of orbit was 8.05+2.68 and 9.15+2.11 mm respectively on the right and left side. Mean distance from infraorbital foramen was 25.45+4.35 mm and 25.42+4 mm respectively on right and left side.

CONCLUSION

The location of ZO and ZF foramen can be population specific and knowledge of its location is important during stabilization of zygomatic fractures, in endoscopic subperiosteal facelift.

Bilateral anomaly of rectus capitis posterior muscles in the suboccipital triangle and its clinical implication

Rectus capitis posterior muscles are located in the suboccipital triangle and function in extension and lateral rotation of the head and neck. There are two of these muscles on each side: the rectus capitis posterior major and the rectus capitis posterior minor. In the present case we observed bilateral double rectus capitis posterior major muscle and bilateral absence of rectus capitis posterior minor muscle. The additional rectus capitis posterior major may put more strain to the spine of the axis and mean time the bilateral absence of rectus capitis posterior minor muscles will result in muscular in coordination in the suboccipital region while balancing the head. The present variation should be considered in the aetiology of cervicogenic headache.

Prediction of postoperative pulmonary reserve in lung resection patients

We performed Ventilation/Perfusion scans for patients planned for thoracotomy with resection of the primary or metastatic lung tumors. We predicted the post-operative FEV1 (Forced Expiratory Volume in first second) using Differential Lung Analysis software.

METHODS

34 patients were evaluated with Ventilation/Perfusion (V/Q) scans. Ventilation scan was performed with Tc-99m DTPA Aerosol and Perfusion Scan with Tc99m MAA, on 2 different days. The numbers of counts in anterior and posterior views of V/Q scans were calculated individually. Anterior and posterior arithmetical mean was calculated and post-operative FEV1 was predicted with the use of Differential Lung Analysis software. In most of the patients, the counts in the ventilation scan were lower and they were related to preoperative FEV1. Depending on the volume of lung resection, i.e. Upper, Middle and Lower zones or Total Pneumonectomy, FEV1 was calculated. Whenever FEV1 was >0.8 (L), the patient was taken up for resection (and if there were no other risk factors, such as cardiac complications, chronic obstructive pulmonary diseases, and any other pathological conditions involving the contralateral lung).

RESULTS

Most of the 34 patients were taken up for lung resection based on our FEV1 predictions. In 7 patients, repeat spirometry (i.e. pulmonary function test) was done at varying intervals after surgical procedures and the variation between preoperative FEV(1) and postoperative FEV(1) was only ±15%, at the most.

CONCLUSION

Postoperative FEV(1) based on V/Q scan and pulmonary function tests helped us to proceed with lung resection after assessment of the pulmonary reserve.

Morphology of the medial meniscus of the knee in human fetuses

OBJECTIVES

The objectives were to study the morphology of the medial menisci in human fetal knee joints and to verify the developmental etiology of the discoid meniscus.

MATERIAL AND METHODS

The study was carried out on 106 fetal knee joints and the morphological variants of the shapes of the medial menisci were macroscopically noted and classified.

RESULTS

From our observations, 46.2% of the medial menisci were crescentic shaped, 23.6% were sided V-shaped, 13.2% had sided U-shape, 9.4% of them were sickle shaped, and 7.5% were C-shaped. In 54.71% of the cases, the medial meniscus shape was different on either side knees of the fetuses. No discoid medial menisci were seen.

CONCLUSIONS

The majority of the knees were having crescentic or semi lunar shaped medial menisci and the shape of the medial meniscus was different on right and left side knee joint of the fetuses in more than fifty percent of the cases. The observations favor Kaplan's theory, as there were no discoid medial menisci observed from the fetuses of various gestational ages. Even the youngest fetus (CRL 88 mm, 14 weeks of gestation) exhibited the medial tibial plateau incompletely covered by the menisci, which did not exhibit the discoid shape. The discoid meniscus must be an abnormal finding and is due to abnormal morphogenesis.

Morphometry of A1 segment of the anterior cerebral artery and its clinical importance

BACKGROUND AND AIM

Anterior cerebral artery, one of the terminal branches of the internal carotid artery is an important vessel taking part in the formation of circle of Willis. It supplies a large part of the medial surface of the cerebral hemisphere containing the areas of motor and somatosensory cortices of the lower limb. Aim of this study was the morphometry of A1 segment of the anterior cerebral artery.

MATERIALS AND METHODS

93 formalin fixed brain specimen of either sex and of Indian origin were studied. The mean length, mean external diameter and the anomalies present in A1 segment of the vessel were studied in detail and photographed.

RESULTS

The mean length of A1 segment of the vessel was 14.49+/-0.28 mm and 14.22+/-0.22 mm on right and left side respectively. The mean external diameter of the vessel on right and left side was 2.12+/-0.07 mm and 2.32+/-0.06 mm respectively. Narrowing, aneurysm formation, buttonhole formation and median anterior cerebral artery were the anomalies seen with an occurrence of 15.05%, 5.37%, 3.22% and 12.9%, respectively. The above anomalies did not have any sex or side predilection.

CONCLUSION

Knowledge of morphometry of the vessel will be of use to neurosurgeons while performing the shunt operation, in assessing the feasibility of such operations and in the choice of patients. From this study we infer that the morphometry of anterior cerebral artery varies in different population and that the neurosurgeons operating should have a thorough knowledge of the possible variations.

Anatomy of plantaris muscle: a study in adult Indians

AIM

The plantaris muscle (PM) and its tendon is subject to considerable variation in both the points of origin and of insertion. The present study was carried out to fi nd the different types of origin, insertion and possible variations of the PM in the population of southern costal region of India.

MATERIALS AND METHODS

52 embalmed (Formalin fixed) cadaver lower limbs of 26 males (age ranged 48-79 years, mean age 68 years) were dissected, to study the origin and insertion of PM. Various dimensions (length and width) of plantaris muscle belly and its tendon were also measured.

RESULTS

Three types of origin and equal number of insertion were noticed in the present study. The PM took origin from type I: Lateral Supracondylar ridge, Capsule of Knee joint and Lateral head of gastrocnemius in 73.07% cases; type II: Capsule of Knee joint and Lateral head of gastronemius in 5.76% cases; type III: Lateral Supracondylar ridge , Capsule of Knee joint , Lateral head of gastrocnemius and fibular collateral ligament in 13.46% cases. The plantaris tendon was inserted into type I: to the flexor retinaculum of foot in 28.84% cases; type II: independently to the os calcaneum in 36.53% cases; type III: to the tendocalcaneus at various levels in 26.92% cases. In four lower limbs (7.69%) the plantaris muscle was completely absent. Additionally the length and width of the plantaris muscle and its tendon were measured to know any side difference. There were no statistically significant differences between the measurements of left and right side (p>0.05).

CONCLUSION

Present study will help the surgeons while attempting various surgical procedures in and around the posterior aspect of knee involving plantaris.

Duplication of falx cerebelli, occipital sinus, and internal occipital crest

The incidence of variations of falx cerebelli was studied in 52 adult cadavers of south Indian origin, at Kasturba Medical College Mangalore, after removal of calvaria. In eight (15.4%) cases, we observed duplicated falx cerebelli along with duplicated occipital sinus and internal occipital crest. The length and the distance between each of the falces were measured. The mean length of the right falces cerebelli was 38 mm and the left was 41 mm. The mean distance between these two falces was 20 mm. No marginal sinus was detected. Each of the falces cerebelli had distinct base and apex and possessed a distinct occipital venous sinus on each attached border. These sinuses were noted to drain into the left and right transverse sinus respectively. After detaching the dura mater from inner bony surface of the occipital bone, it was noted that there were two distinct internal occipital crests arising and diverging inferiorly near the posterolateral borders of foramen magnum. The brain from these cadavers appeared grossly normal with no defect of the vermis. Neurosurgeons and neuroradiologists should be aware of such variations, as these could be potential sources of hemorrhage during suboccipital approaches or may lead to erroneous interpretations of imaging of the posterior cranial fossa.

An anomalous belly of sternothyroid muscle and its significance

The sternothyroid muscle and other infrahyoid muscles play a vital role in the process of vocalization, swallowing and mastication by mobilizing the hyoid bone and thyroid cartilage. During routine dissection of a 70-year-old male cadaver, we observed an anomalous sternothyroid muscle. It was arising from the posterior surface of the manubrium sterni and partly from the cartilage of the first rib. After a distance of 3.3 cm, the belly of sternothyroid muscle was divided into lateral and medial fibers. The lateral belly was inserted above the oblique line on the lamina of the thyroid cartilage, but the medial additional belly turned into a tendon, which was crossing over the thyroid artery and inserted to the hyoid bone and intermediate tendon of digastric muscles. The superior thyroid artery was below the above tendon on its way to the thyroid gland. The muscle was innervated by a branch from the ansa cervicalis.

Morphometry of posterior cerebral artery: embryological and clinical significance

Posterior cerebral artery, terminal branch of basilar artery joins the posterior communicating artery to help complete the circulus arteriosus cerebri in human beings. A study of 89 formalin-fixed brain specimen of either sex and of Indian origin has showed that the mean length and diameter of the posterior cerebral artery was 6.75 +/- 1.482 mm and 1.7 +/- 0.7 mm respectively. Anomalous origin of the posterior cerebral artery was the only variation found during the present study. The incidence of occurrence of the particular variant was 2.2%. The variation did not have any sex or side predilection.

The palmaris longus muscle: its anatomic variations and functional morphology

The functional morphology and evolution of the superficial forearm flexor, the palmaris longus, have long fascinated kinesiologists, physical anthropologists and anatomists alike. The anomalies, agenesis, variations and polymorphic presentation of the muscle, coupled with its biomechanical role in the performance of flexion and supination through distal articulations in the upper limb, have formed the base for many studies found in medical literature. We present data from published sources, along with our observations on the kinetics of palmaris longus, drawn from a series of dissections done on 30 cadavers. Complete agenesis was seen in four limbs. Reversal in the muscle-tendon orientation was seen in two limbs and duplication in one limb. The functional dynamics of the muscle and the clinical implication of its modifications in humans are discussed. We believe that every surgeon must be aware of the variations, since this, otherwise unimportant muscle, provides a very useful graft in tendon surgery.

Multiple variations of the extensor tendons of the forearm

Anatomic variations of the extensor tendons of the forearm are frequent and its knowledge is important to assess the diseased and traumatized hand. During routine cadaveric dissection in the Department of Anatomy, Kasturba Medical College, Mangalore, India, we came across unusual variations in the left upper limb of a 51-years-old male cadaver. The variants are, the complete absence of the extensor pollicis brevis (EPB), the abductor pollicis longus (APL) having six slips of insertion with additional muscle slip from the brachio-radialis (BR). The extensor digitorum communis (EDC) had five tendon slips, the extra tendon splits close to the metacarpo-phalangeal (MP) joint and contribute to the tendons of the ring and little fingers. The number of accessory tendons of APL has functional significance in the development of de Quervain's stenosing tendovaginitis. The present case is unique in the sense that, all the three variations are present in the ipsilateral upper limb. The occurrence of these anomalies and its clinical and embryological significance are discussed.

Additional branches of celiac trunk and its clinical significance

The anatomical variations of the abdominal arteries are important due to its clinical significance. Various types of vascular anomalies are frequently found in human abdominal viscera, during cadaveric dissection and diagnostic radiological imaging. The present report describes a variation in the celiac trunk as found during routine dissection in a 59-year-old male cadaver. The celiac trunk (CT) was unusually lengthy and took origin from the left antero-lateral surface of the abdominal aorta. Altogether, there were five branches, including three classic branches of CT. The left phrenic artery (LPA) was the first branch of the CT. The remaining four branches were left gastric artery (LGA), splenic artery (SA), common hepatic artery (CHA) and gastroduodenal artery (GDA). There was an arterial loop between the posterior branches of the superior pancreatico-duodenal artery (SPDA), arising from the GDA, and the posterior branch of the inferior pancreatico-duodenal artery (IPDA), arising from the superior mesenteric artery (SMA). The arterial loop formed by the above arteries, supplied the head of the pancreas and duodeno-jejunal flexure. The embryological and clinical significance of above variations has been described.

Multiple muscular anomalies of upper extremity: a cadaveric study

During routine cadaveric dissection, we encountered multiple muscular anomalies in a 58-year-old embalmed male cadaver. All the variations were encountered on the flexor compartment of right upper limb. The anomalies include an axillary arch (Aa) in the axilla, a third head of biceps brachii (Thb) in the arm, a reverse palmaris longus (Rpl) and a Gantzer's muscle (Gm) in the forearm and an unusually large palmaris brevis muscle (Pbm) in the palm. Anatomical description is achieved by measuring the length, width and attachments of the above-mentioned variants. The morphological and clinical significance of the anomalous muscles are discussed.

The branching pattern and communications of the musculocutaneous nerve

Anatomical variations of peripheral nerves are important and can help explain otherwise incomprehensible clinical findings. A study of 26 right and 18 left formalin-preserved upper limbs identified the fact that the musculocutaneous nerve is subject to considerable anatomical variation, including communication with the median nerve. A study of its branching pattern made us aware of why debility after trauma to the lateral aspect of the upper arm may be more than expected, and this study considers the clinical and surgical importance of these variations of the musculocutaneous nerve.