Thesis Abstract

<div>               <b>ABSTARCT&nbsp;</b><br></div>This study was set to radiologically evaluate the normal posterior- Anterior chest radiographs of Gombe adults, which was undertaken using 500 chest radiographs that were reported normal by radiologist, males (n = 250 and mean age 43.38 ± 16.55) and females (n = 250 and mean age 39.28 ± 14.68). In males the mean length of left clavicles was 163.70 ± 10.52 mm and the right was 157.65 ± 10.06 mm, while in females the mean length of the left clavicles was 150.47 ± 8.58 mm and the right clavicle was found to be 144.72 ± 8.36 mm, also the males mean mid – thickness of the left clavicles was 13.38 ± 1.42 mm and right clavicle was 14.06 ± 1.38 mm, while in females the mean mid- thickness of the left clavicle was 11.19 ± 1.09 mm and the right clavicle was 11.81 ± 0.89 mm, in which the sex difference in the mean length and mid- thickness of the clavicles on both left and right sides was found to be highly significance (P&lt;0.001) with the males having longer and thicker clavicles than females, the clavicles in both males and females show side difference with the right clavicles being significantly the shorter and thicker than left clavicles. In males mean height of left scapular 166.99 ± 14.40 was found to be significantly different from right 161.07 ± 15.27 with (P&lt;0.001), likewise the females mean height of the left scapular was significantly different from right (P&lt;0.001). The males mean width of the left scapular was 84.89 ± 8.90 mm and right scapular was found to be 83.32 ± 9.46 mm, the females mean width of the left scapular was 77.57 ± 7.96 mm and the width of right scapular was 74.44±10.63 mm, which indicates that the scapula in the both side were significantly greater in males than in females with P&lt;0.001. The thoracic dimension were also found to be greater in males than in females, in which the males thoracic diameter at T3 was 213.16 ± 17.36 mm, T5 was 256.81 ± 15.76 mm, T7 ix was 276.93 ± 16.64 mm and T9 was 288.94 ± 19.50 mm, while the thoracic diameter in females at T3 was 200.90 ± 15.76 mm, T5 was 238.88 ± 14.36 mm, T7 was 257.06 ± 15.28 mm and T9 was 268.65 ± 18.96 mm, where the differences were highly significant with P&lt; 0.001, the height of left and right hemidiaphragm dome shows significance difference between males and females, with the height of left and right hemidiaphragm dome in males as 241.23 ± 20.04 mm and 222.34 ± 20.57 mm and in females as 224.14 ± 12.78 mm respectively. The left and right hemidiaphragm dome shows side difference in males and females (p&lt;0.001). The long and short axis of cardiac ellipsoid were measured in males as 145.61 ± 7.19 mm and 116.84 ± 8.76 mm, while in females as 138.44 ± 8.31 mm and 111.02 ± 6.73 mm respectively, this indicated that the long and short axis of cardiac ellipsoid are significantly greater in males than in females (p&lt;0.001). The shape of C7/T1 and T1/T2 intervertebral discs also show greater sex difference (P&lt;0.001) in which the males intervertebral&nbsp; disc were mostly curved (inverted V) at both levels, whereas the females intervertebral disc is parallel in shaped at both levels.

Thesis Overview

<p> <b>1.0 INTRODUCTION</b></p><p><b>1.1 BACKGROUND OF STUDY</b></p><p>Identification of the sex of skeletonized or dismembered human bodies is the first step in bio archaeological and forensic anthropological investigations (Derya et al., 2010). Positive identification of the deceased is necessary for an accurate death certificate to be filed, a Will to be executed, benefits to be distributed, and most importantly for families to find closure. Decedent identification is also necessary for the conclusive investigation of homicide (Brogdon, 1998). Methods of identification include fingerprints, dental radiograph comparison, axial and appendicular radiograph comparison, and in selected cases, DNA analysis. Visual identification alone is often unreliable due to thermal damage,immersion, mutilation, disarticulation or decomposition of the remains (Fierro, 1993).<br>The human thoracic region is relatively important in biological and forensic anthropological studies as it is active between adolescent growth and adult maturational and degenerative periods (Carla et al., 2005). As such, it presents an opportunity to obtain information with respect to personal identification during much of an individual‘s life span and may be especially important when dealing with only partial remains, where sex determination and age estimation may become more difficult (Carla et al., 2005). Most anthropological methods for dealing with situations of questionable identity have been developed for use on dry bone and, at the very least, require a partially or totally defleshed body. While all individuals requiring a forensic examination are in some stage of decomposition, in the majority of situations these bodies are relatively intact. In such instances it may be a straightforward procedure to initiate identification processes using fingerprints, visual confirmation, unique physical characteristics, dental records, or past medical procedures as corroborating evidence. However, on occasion, an individual may be too decomposed to successfully use these methods or ante-mortem medical and/or dental records may be inadequate, unavailable, or difficult to locate. Thus any technique that is able to facilitate a rapid, simple, and inexpensive determination of sex is extremely important. Of particular relevance to this study, is the determination of sex in forensic contexts from radiographs of the chest (McComick et al., 1985).</p><p>The key to the successful determination of sex is the use of measurements that have shown consistently high replicability and accuracy in allocating both male and female sex. One of the first metric methods, Hyrtl‘s Law (Hyrtl, 1893), has been using sternal size for over 170 years as an estimator of sex. According to Hyrtl, in females the manubrium generally exceeds half the length of the sternal body whereas in males the body of the sternum is usually twice as long as the manubrium. Numerous other investigators have used sternal or thoracic area measurements as useful predictors of sex (Dwight, 1881 and 1890; Paterson, 1904; Pons, 1956; Ashley, 1956; Stewart, 1983; Jit, 1985; Iscan, 1985). Stewart and McCormick (1983) examined 64 radiographs to determine if there was a relationship between sternal length and pattern of costal cartilage mineralization. They observed that mean manubrio-mesosternal length in male is &gt;158 mm, while in female is &lt;142 mm, which correctly predicted sex in 40 of the 42 (95.2 %) applicable cases with mineralization patterns accurately predicting sex in 38 of the 41 (92.7 %) applicable cases. Using both methods, they achieved an accuracy rate of 96.4 % on 87.5 %, or on 56 of the 64 cases examined. In 1985, McCormick et al. examined sex differences in chest radiographs of 698 males and 435 females over the age of 20 years. Which was made directly from high-resolution chest radiographs, thus eliminating the need to de-flesh the individual (McCormick et al., 1985). Francois et al. (2003) and Bellemare et al. (2001) examined and measured the thoracic dimensions of the chest radiographs of 40 normal subjects (21 males and 19 females) at the level of third, fifth, seventh and ninth vertebrae and ribs, the Height of each hemidiaphragm dome below the first thoracic vertebra on the posterioanterior (PA) films and averaged and the inclination of rib was as acute angle formed by the lower border of the sixth rib and the vertical the lateral films, and found the thoracic dimension of males is greater than females</p><p>1.1.1&nbsp;<b>BRIEF HISTORY OF GOMBE STATE</b><br>Gombe State was created out of former Bauchi State in 1st October 1996 by Late General Sani Abacha administration, it occupies a total land area of about 20, 265 sq. km. The topography of the state is mountainously undulating and hilly to the south and flatly open-plain to the north (Ibrahim, 2004; Harper, 2009). The Gongola river traverses the state, watering most of the north and north-eastern parts of it before emptying into river Benue at Numan. Numerous streams that are mostly seasonal also serve as tributaries to the Gongola river (Ibrahim 2004; Harper, 2009).</p><p>The vegetation of the state is generally guinea savannah grassland with concentration of woodlands in the south-east and south-west. Gombe State is generally warm with average maximum temperature during the hot season not exceeding 300 centigrade. There are two distinct seasons: the dry season (November to March) and wet season(April to October). Average annual rainfall is 850 mm. The State is endowed with rich agricultural land and about 80% of the people are mainly peasant farmers involved in farming food and cash crops such as millet, sorghum, maize, vegetable, cotton and groundnut, though rain-fed as well as irrigation agriculture. Some of the people are also engaged in livestock farming, fishing and craft works (Ibrahim, 2004; Harper, 2009). Gombe State has large deposits of solid minerals such as limestone, gypsum, kaolin, silica, talc, uranium and dolomite (Ibrahim, 2004; Harper, 2009).</p><p>1.1.1.1&nbsp;&nbsp;<b>DEMOGRAPHY AND PEOPLE OF GOMBE STATE</b><br>The 1998 census returned a population of 1,895,597 people for Gombe state. By 2004 and 2006, it was projected to 2,174,118 and 2,353,000 people, respectively. There are slightly more males than females in the State. The sex ratio being 100 males to 98.9 females. That is, the gender composition of the population is almost equally distributed (Ibrahim, 2004; Census, 2006).<br>Gombe state has a multi-ethnic composition mainly of Fulani, Tangale, Waja, Bolawa, Tera, Jukun, Pero, Gera, Tula, Chamawa, Lunguda, Dadiya, Kanuri, Hausa, Kamo, Jaraamong others. In addition, there is quite an appreciable population of Yoruba and Igbo in the State (Ibrahim, 2004; Census, 2006).<br>Gombe State has a rich cultural heritage. Crafts, such as leather works, cloth weaving and calabash decoration abound in the state. There are also notable musical forms and dances performed by different groups. e.g Ngorda in Yamaltu-Deba, Bid-bid dance group in Billiri (Ibrahim, 2004; Census, 2006). The state is also multi-religious, with Muslims and Christians being the most predominant groups. Traditional religion also exists to a lesser degree, e.g eku among the Tangale communities and nabakwa among the Tula (Ibrahim, 2004; Census, 2006).</p><p><b>1.2 STATEMENT OF THE RESEARCH PROBLEM</b><br>In conditions of natural or man made mass disasters, genocides or aircraft accidents where direct or positive identification of victims is difficult, there is need for an accurate, timely, simple and inexpensive method of sex determination. For the purpose of identifying victims, one of such method that has proved reliable is the use of high resolution chest radiographs (McCormick et al., 1985).<br>Because there are no reference values for sex determination using normal chest radiographs for the people of Gombe State, Nigeria, there is a need to carry out a study in order to fill this gap.</p><p><b>1.3 AIM AND OBJECTIVES OF THE STUDY</b><br><b><i>1.3.1 Aim of the study</i></b><br>The aim of the present study is to radiologically evaluate the anatomy of normal postero-anterior chest radiographs of adults in Gombe.</p><p><b><i>1.3.2 Objectives of the study</i></b><br>The objectives of this study are to:</p><p>i. Evaluate the radiological anatomy of adult in Gombe using normal posteroanterior chest radiographs.</p><p>ii. Establish reference values for determination of sex from the dimensions of structures in the normal chest radiographs.</p><p>iii. Investigate the radiological anatomy of adults in Gombe according to sex and age using normal posteroanterior chest radiographs .</p><p>iv. Investigate the relationship between the scapula, clavicle, heart, and chest dimensions in sex determination using normal chest radiographs.</p><p>v. Investigate gender difference in the intervetebral disc shape in chest radiographs of normal Gombe adults.<br><br></p>