Some anatomical and morphometric observations in the transverse foramina of the atlas among Kenyans

The transverse foramen, which transmits the vertebral vessels, is the result of special formation of the cervical transverse processes. It is formed by a vestigial costal element fused to the body of the originally true transverse process of the vertebra. In the atlas, where the vertebral artery exits the transverse foramen to enter the cranium, many bony variations have been described, and some are attributable to tortuosity of the vessel, as well as stress forces on the neck. The transverse foramen of the atlas has not been studied in terms of shape, morphometry, presence or absence and bilateral differences. This may shed light on the side differences in neck and vertebra-basilar pathology. A hundred and two atlases obtained from the Osteology Department of National Museums of Kenya were observed for presence, shape and variations of the transverse foramen. Accessory transverse foramina were noted, as well as missing foramina. Anteroposterior and mediolateral diameters of the foramina were taken and the area calculated. Out of the 102 vertebra studied (204 foramina transversaria), 8 incomplete foramina were observed, 6 on the right side and 2 bilateral. There were 4 double transverse foramina observed, 1 on the left and 3 on the right side. All atlases had foramina transversaria. The foramina categorized into types 1 to 5 using a recognized criterion. On the right side, type 4 was predominant (40.2%), while on the left, types 2 and 5 were predominant (39.2% each). Morphometrically, the right and left transverse foramina had mean cross-sectional area of 36.30mm2 and 37.20mm2 respectively. The presence of variations in the foramen transversaria is predominant on the right side. Further, the right foramina have a smaller cross-sectional area. These should be taken into account during posterior cervical approaches, as well as during evaluation of cervicogenic syndromes.Keywords: Atlas vertebrae, transverse foramina, morphometr

Gender-associated violence at a women's hospital in Nairobi, Kenya

Objective: To describe the pattern of gender-associated violence amongst adult survivors. Design: Descriptive case analysis of prospectively collected data. Setting: The gender violence and recovery centre (GVRC), a shelter and violence treatment facility for the gender-associated violence at the Nairobi Women\'s hospital (NWH). Subjects: Data on 663 consecutive adult patients who presented to GVRC between February 2003 and April 2004 were evaluated. Results: The patients age ranged from 18 to 74 years (mean 27.7 years). Four hundred and eight patients (61.5%) presented following sexual assault. Most of assaults were perpetrated at night. A stranger was the assault perpetrator in 75.1% and 2% of sexual and non-sexual assault respectively. An intimate partner was the perpetrator in majority (86.5%) of nonsexual violence. Most physical injuries were minor bruises and swellings. The rate of positive spermatozoa from high vaginal swabs was only 15.9% in cases of sexual assault. Sexual assault was significantly associated with single status of the victim and assault by more than one assailant. Conclusions: Violence against women is a common public health problem in the city of Nairobi. Women are vulnerable both in and out of the home. More efforts, including massive public education, are needed to protect this vulnerable population. East African Medical Journal Vol. 85 (7) 2008: pp. 347-35

Conventional and variant termination of the portal vein in a black Kenyan population

Background: Knowledge of the variant terminations of the portal vein is important in surgical and interventional radiological procedures of the liver. Their pattern and frequency are important in planning surgery to minimize complications. They differ between populations, but data from Africa is unavailable. Aim: To investigate the variant termination of the main portal vein. Materials and Methods: One hundred livers from adult black Kenyans (age range 35 – 79 years) were studied at the Department of Human Anatomy, University of Nairobi, Kenya, by gross dissection. The livers were cleared of blood, fixed with 10% formaldehyde solution and the venous system infused with Acrylate monomers to keep the veins firm. The level of termination relative to the capsule and the branching pattern of the portal vein were examined.  Various patterns were photographed using a digital camera. Data was analyzed using SPSS version 16.0 for windows and presented in tables and macrographs. Results: Main portal vein termination was extracapsular in 14%, capsular in 40% and intrahepatic in 46%. Variant termination occurred in 49% of cases while conventional bifurcation occurred in 51% cases. Types, 2, 3 and 4 pattern of termination of main portal vein occurred in 15%, 22% and 12% cases respectively. The level of termination of the MPV had a positive correlation with its pattern (p=0.05). Conclusions: The high prevalence of variant termination of MPV in the current study suggests that the population is more vulnerable to inadvertent injury during surgery and radiological intervention. Besides, an extra hepatic termination of the MPV is more likely to have a conventional branching pattern compared to an intra-hepatic termination

Variant anatomy of the right portal vein in a black Kenyan population

Surface mapping of the liver before invasive procedures depends on a proper understanding of its segmental vasculature. The right portal vein ramification and lengths show marked variations and these mostly involve its right posterior sectoral branch. Their incidence is variable among populations and altogether undocumented among Africans. One hundred livers obtained during autopsies and dissections at the Department of Human anatomy, University of Nairobi, were used in this study. Gross dissection was done to reveal and determine the branching pattern of the right portal vein and the origin of the right posterior sector branch. The lengths of the right portal vein were also measured and recorded. When present, the right portal vein terminated by bifurcation in 61% of the cases, trifurcated in 20.8% and quadrifircated in 18.2%. Its length was between 0.5cm and 4cm. The right posterior sector vein was given off the main portal vein in 34 cases, the common left portal vein trunk in 15 cases, and the right portal vein in 42 cases. In 9 cases, it was not observed at the porta hepatis. We report significant different incidences of the variant anatomy of the right portal vein compared to those found in previous studies and this should be borne in mind when doing surgical interventions.Keywords: Segmentectomy, transjugular, Surface mapping, Bifurcatio

Sex variations in the structure of human atrioventricular annuli

Atrioventricular annuli are important in haemodynamic flexibility, competence, and support for tricuspid and mitral valves. The anatomical features of the annuli, such as circumference, organisation of connective tissue fibres, myocardium, and cellularity, may predispose to annular insufficiency and valvular incompetence. These pathologies occur more commonly in females, although the anatomical basis for this disparity is unclear. Sex variation in the structure of the annuli is important in providing a morphological basis for the patterns of these diseases. This study therefore aimed to determine the sex variations in the structure of human atrioventricular annuli. One hundred and one hearts (48 males, 53 females) obtained from the Department of Human Anatomy of the University of Nairobi were studied. Annular circumferences were measured using a flexible ruler and corrected for heart weight. Results were analysed using SPSS version 17.0 and sex differences determined using student’s t-test. A p-value of less than 0.05 was considered significant. For light microscopy, specimens were harvested within 48 hours post-mortem, processed, sectioned, and stained with Masson’s trichrome and Weigert’s elastic stain with van Gieson counterstaining. Females had significantly larger annular circumferences than males after correcting for heart weight (p ≤ 0.05). Histologically, myocardium was consistently present in all male annuli while this was absent in females except in one specimen. The annuli were more elastic and cellular in males especially in the annulo-myocardial and annulo-valvular zones, respectively. The corrected larger annular circumference in females may limit heart valve coaptation during cardiac cycle and may be a risk factor for valvular insufficiency. The predominance of myocardium, annular cellularity, and elasticity may be more protective against heart valve incompetence in males than in females

Age changes in the structure of human Atrioventricular annuli

Atrioventricular annuli are important in hemodynamic stability and support to tricuspid and mitral valves. Anatomical features of the annuli such as circumference, organization of connective tissue fibers, myocardium and cellularity may predispose to annular insufficiency and valvular incompetence. These pathologies increase with age and are more common in females, although the anatomical basis for this disparity remains unclear. This study therefore aimed to investigate age-related changes in the structure of human atrioventricular annuli. One hundred and one hearts (48males, 53 females) from subjects (15 to 60 years) were studied in three age groups (≤ 20 yrs, 21-39 yrs and 40-60 yrs). Annular circumferences were measured and corrected for heart weight. Routine histology was carried out on 21 hearts. Differences in annular circumference between the age groups were determined using one-way ANOVA while gender differences were determined using independent Students’t-test. Overall, females had significantly larger annular circumference than males after correcting for heart weight (p ≤0.05). The annular circumference generally increased with age however there was a significant increase in the 21-39 year age group (p ≤0.05). Microscopically, myocardium was consistently present in males but absent in females except in one specimen. The collagen fiber density increased with age in both gender as the fibers became more irregular. The annular cellularity, elasticity and myocardial content also declined with increasing age. The significantly wider annular circumference in the 21-39 year age group is clinically important as wider circumference is associated with decreased heart valve co-aptation and valvular incompetence. This may suggest an earlier predisposition to this pathology in the study population. The age-related decrease in annular cellularity, elasticity and myocardial content may explain the higher incidence of valvular incompetence with increasing age.Key words: Atrioventricular annuli; Age changes; Valve incompetence

Groin Hernia in Mulago hospital, Kampala.

A prospective descriptive study based on 208 cases of groin hernia that had surgery at Mulago Hospital over a 12-months period beginning on 1st January 2000 was undertaken. There were more males than females. The mean age was 35.4 years with the mode and median of 40 and 33 years respectively. Patients under 15 years were 37 (17.8%) and had a peak incidence in the 1-3 years age group while in adults the peak was in the 24-34 years age group. Only 2 girls were seen in the under 15 years old group. Most females (86%) who presented with groin hernias were aged above 34 years. There were 195 (93.7%) inguinal hernias of which 159 (81.5%) were indirect inguinal hernias and 34 (17.4%) were of the direct inguinal variety. Busoga hernias were diagnosed in only 4 (2.05%) of inguinal hernias. There were only 13 (6.2%) femoral hernias. Post-operative complications occurred in 41.8% of the cases. There was one death. (0.48% mortality)

Femoral hernia at Mulago hospital, Uganda

Objective: To determine the incidence, pattern and the immediate outcome of femoral hernia surgery in Mulago Hospital. Methods: A hospital based descriptive study during which a questionnaire was drafted to study all consecutive patients operated for femoral hernia over a period of twelve months. Results: There were 13 patients with 13 femoral hernias accounting for 6.3% of all groin hernias operated on in the same period. The age ranged from 42 years to 70 years old with a mean of 54.6 years old. All the patients were females with 12 of them (92.3%) being parous. Ten (76.9%) presented with strangulation. Three had wound complications and one had chest infection post-operatively. More than fifty percent of patients were discharged within the first three post-operative days. There was no mortality. Conclusion: Though rare, femoral hernias have a high risk of strangulation and hence prone to adverse sequelae post-operatively. All medical officers should familiarize themselves with early diagnosis and operative intervention of this relatively rare but dangerous hernia