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
reatment of cervical incompetence by cerclage and other methods has yet to be standardized, as its diagnosis is not uniformly accepted. Its diagnosis, particularly in the African setting, is mostly based on past obstetric history of pregnancy losses, while in developed centres; ultrasound diagnosis is increasingly being used. The mainstay of treatment in developing countries is cervical cerclage, although the indications and contraindications of this mode of treatment are not documented. Our aim was to appraise this practice in terms of patient characteristics, the diagnostic process and management at the Kenyatta National Hospital, Nairobi, Kenya. This was a descriptive retrospective study over 9 years. Predesigned questionnaires were employed to collect data on patient’s socio-demographic profile, presentation, risk factors, diagnosis and management of cervical incompetence. Chisquared test and student’s t-test were used to correlate variables. A total of 199 patients were treated for cervical incompetence, with the patient mean age being 27.97. 87.4% of the patients (p=0.02) were in the 20 to 35 years category. Most of the patients (60.1%) were of low socio-economic status. Cervical cerclage was employed in all the patients, although ultrasound investigation was not employed in 65.8% of them. Diagnosis of cervical incompetence still relies on history of previous pregnancy losses, with the standard transvaginal ultrasound relatively unemployed. There is need to intensify investigations for this condition, standardize the indications for cerclage, and diversify management to other newer modalities.
Background: The diversity of benign jaw tumours may cause difficulty in a correct diagnosis and insti-tution of an appropriate treatment. Data on the prevalence of these tumours is scarce from the Afri-can continent. We present a 19-year audit of benign jaw tumours and tumour-like lesions at a University teaching hospital in Nairobi, Kenya. Methods: Histo-pathological records were retrieved and re-examined from the Department of Oral and Maxillofacial pa-thology, University of Nairobi from 1992 to 2011. The jaw tumours were classified according to the latest WHO classification. Results: During the 19-year audit, 4257 biopsies were processed of which 597 (14.02%) were jaw tumours within an age range of between 4 to 86 years. There was greater number of odontogenic tumours 417 (69.85%) than the bone related lesions 180 (30.15%). Of the odontogenic tumours, the epithet- lial and in the bone related types, the fibro-osseous lesions were frequent. Conclusion: Ameloblastoma and ossifying fibroma were the most frequent tumours reported in this audit. The information regarding the prevalence of these tumours is scarce from the conti-nent and can be useful in early detection and man-agement before they cause facial deformity.
Unilateral variations in the formation of the median nerve, with the presence of the third head of the biceps brachii entrapping the nerve are very rare. These variations were observed on the right side, of a 30-year-old male cadaver during routine dissection at the Department of Human Anatomy, University of Nairobi. The median nerve was formed by the union of three contributions; two from the lateral cord and one from the medial cord. An additional head of the biceps brachii looped over the formed median nerve. On the left side, the median nerve was formed classically by single contributions from the medial and the lateral cords. These variations are clinically important because symptoms of high median nerve compression arising from similar formations are often confused with more common causes such as radiculopathy and carpal tunnel syndrome.
Background: Knowledge of the variant anatomy of the brachial artery is important in radial arterial grafts for coronary bypass, percutaneous trans-radial approach to coronary angiography, angioplasty and flap surgery. These variations show ethnic differences but data from black populations are scarce. This study therefore describes the course in relation with median nerve, level and pattern of termination of brachial artery in a black Kenyan population.
Methods: This was a cadaveric dissection study of 162 upper limbs at the Department of Human Anatomy University of Nairobi, Kenya. The brachial artery was exposed entirely from the lower border of teres major to its point of termination. The course in relation to the median nerve and the level of termination were recorded. The results were analyzed using SPSS version 17.0 for Windows.
Results: 72.2% of the brachial arteries followed the classical pattern described in Gray’s Anatomy. Superfi cial brachioradial and superficial brachial arteries were present in 12.3% and 6.1% of the cases respectively. Brachial artery terminated at the radial neck in 79% of the cases, radial tuberosity (8.6%), and proximal arm (11.1%), mid arm (1.2%). Pattern of termination was either a bifurcation into the radial and ulnar arteries (90.1%) or trifurcation into radial, ulnar and common interosseous arteries (9.3%). We also report a case of trifurcation of the brachial artery into the profunda brachii, radial and ulnar arteries (0.6%).
Conclusion: Variations of the brachial artery in its relationship with the median nerve, level and pattern of termination are common. These may complicate arm surgical exposures, fl ap and vascular surgery. Pre-operative angiographic evaluation is recommended.
Background: Characteristics of Prolapsed Intervertebral Disc (PID) in Africa, reports are scanty and
Objectives: To evaluate the distribution of PID by location, age, gender and predisposing factors among
African patients at our hospital, the largest regional referral and teaching hospital in Kenya.
Patients and Methods: Six hundred and three cases (267 males, 336 females) of prolapsed intervertebral
disc over 11 years between January 1997 and December 2007 were analyzed for location, number of
prolapsed disks, gender, age and predisposing conditions.
Results: Of the determined locations L4/5 was the commonest (42.3%), followed by L5/S1 (25.5%).
Seventy seven (20.9%) of the patients had multiple prolapsed disks. 1.4% were in the cervical region,
and only one in the thoracic. PID was commonest in the 31 – 50 year age group females (M: F is 1:1.26,
p=0.00), with mean age 40.90+13.80 years, (range between 11- 85 years).
Conclusions: PID in Kenya is commonest in the lower lumbar region of young people more in females
and is associated with trauma.
Variations in the origin and termination of the profunda brachii artery (PBA) are rarely described in literature.
Knowledge of this unusual anatomy is important during brachial artery catheteriz
ation and harvesting of lateral arm flaps. One hundred and forty four arms from 72 cadavers of black Kenyans were dissected and examined for the origin and termination of PBA at the Department of Human Anatomy, University of Nairobi, Kenya. The patterns of origin and termination of the PBA were observed and recorded. The PBA was present in all the cases. It arose from the brachial, axillary and a common stem with the superior ulnar collateral arteries in 96.9%, 1.4 % and 1.7% of the cases respectively. It displayed duplication and early branching in 11.1% and 16.7% of the cases respectively. The high incidence of duplication and early branching makes it vulnerable to inadvertent injury during fractures of the humerus, brachial artery catheterization and may complicate lateral arm flaps. Preoperative angiographic evaluation is therefore recommended.
Variant origin of lateral circumflex femoral artery (FA) is important during harvesting of anterolateral thigh flaps, aortopopliteal by-pass, coronary artery grafting, and vascularised iliac transplant. The frequencies of variant origins display ethnic variations, but reports from black Africans are scarce. This study, therefore, aimed to describe the variant origins of lateral circumflex FA in a black Kenyan population. Eighty-four (42 right and 42 left) lateral femoral circumflex arteries from 42 cadavers (31 male and 11 female) were exposed by dissection of the femoral triangles at the Department of Human Anatomy, University of Nairobi. The arteries were then traced proximally to their parent trunks. Sites of origin were recorded and representative images of the variations taken using a high-resolution digital camera. Data were analysed using Statistical Program for Social Scientists version 16.0 for Windows and presented in tables and macrographs. The lateral circumflex artery was a branch of the profunda femoris in only 65.5% of cases. Variant origins included from a common trunk with medial circumflex artery (14.3%), with profunda femoris (10.7%), as a trifurcation with profunda femoris and medial circumflex FA (7.1%), and from FA (2.4%). Variant origin of the lateral circumflex FA occurred in nearly 35% of the Kenyan population studied, much lower than in oriental populations. The most frequent variant origin is as a common trunk with medial circumflex femoral and profunda femoris, with a very low prevalence of origin from FA. The unusual origins make the artery more vulnerable to iatrogenic injury during surgery and catheterisation. Preoperative angiographic evaluation of the femoral arterial system is recommended.
Sternal foramina may pose a great hazard during sternal puncture, due to inadvertent cardiac or great vessel injury. They can also be misinterpreted as osteolytic lesions in cross-sectional imaging of the sternum. On the other hand, variant xiphoid morphology such as bifid, duplicated, or trifurcated may be mistaken for fractures during imaging. The distribution of these anomalies differs between populations, but data from Africans is scarcely reported. This study therefore aimed to investigate the distribution and frequency of sternal foramina and variant xiphoid morphology in a Kenyan population. Eighty formalin-fixed adult sterna (42 males [M], 38 females [F]) of age range 18-45 years were studied during dissection at the Department of Human Anatomy, University of Nairobi. Soft tissues were removed from the macerated sterna by blunt dissection and foramina recorded in the manubrium, body, and xiphoid process. The xiphisternal ending was classified as single, bifurcated (2 xiphoid processes with a common stem), or duplicated (2 xiphoid processes with separate stems). Results were analysed using SPSS version 17.0. Foramina were present in 11 specimens (13.8%): 7 M, 4 F. The highest frequency was in the sternal body (n = 9), where they predominantly occurred at the 5th intercostal segment. Xiphoid foramina were present in 2 specimens (both males) (2.5%), while manubrial foramen was not encountered. The xiphisternum ended as a single process in 64 cases (34 M, 30 F) (80%). It bifurcated in 10 cases (5 M, 5 F) (12.5%), and duplicated in 6 cases (4 M, 2 F) (7.5%). There were no cases of trifurcation. Sternal foramina in Kenyans vary in distribution and show higher frequency than in other populations. These variations may complicate sternal puncture, and due caution is recommended. The variant xiphisternal morphology may raise alarm for xiphoid fractures and may therefore be considered a differential.
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.
Uterine artery undergoes structural modifications at different physiologic states. It is expected that due to its unique course, hemodynamic stresses in the vessel would vary resulting in differences in arterial dimensions. The objective of this study was to investigate regional morphometric changes in the human uterine artery.
A 62 year-old male presented with a progressing three week history of respiratory distress, tachypnoea, right sided chest stony dullness and mediastinal shift to the left. He had no clinical, laboratory or radiological evidence of pulmonary tuberculosis or malignancy and could not remember any history of chest trauma. Chest X ray revealed massive right side pleural effusion. A Computerised Tomography (CT) scan showed six consecutive rib (rib 5- 10) fractures with no callus formation. Chest tube insertion drained 4.7L of straw coloured effusion that did not recur subsequently. We suspect that multiple rib fractures irritated the pleura, resulting in a massive pleural effusion. A review of the literature indicates this to be a rare finding.
Position and source of blood supply to the human carotid body displays population variations. These data are important during surgical procedures and diagnostic imaging in the neck but are only scarcely reported and altogether missing for the Kenyan population. The aim of this study was to describe the position and blood supply of the carotid body in a Kenyan populati on. A descriptive cross-sectional study at the Department of Human Anatomy, University of Nairobi, was designed. 136 common carotid arteries and their bifurcations were exposed by gross dissection. The carotid body was identified as a small oval structure embedded in the blood vessel adventitia. Position and source of blood supply were photographed. Data are presented by tables and macrographs. 138 carotid bodies were identified. Commonest position was carotid bifurcation (75.4%) followed by external carotid artery (10.2%), internal carotid artery (7.2%) and ascending pharyngeal artery (7.2%). Sources of arterial blood supply included the carotid bifurcation (51.4%), ascending pharyngeal (21.0%), external carotid (17.4%) and internal carotid (10.2%) arteries. Position and blood supply of the carotid body in the Kenyan population displays a different profile of variations from those described in other populations. Neck surgeons should be aware of these to avoid inadvertent injury.