ABSTRACT

CORRESPONDING AUTHOR:
Dr. Roshan Chanchlani,
# 1/6 - Idgah Kothi, Doctors Enclave,
Near Filter Plant, Idgah Hills,
Bhopal – 462001, M. P.
E-mail: roshanchanchlani@gmail.com

ABSTRACT: BACKGROUND: all sites of herniation possess one feature in common i.e. the zone of weakness. The lowness of pubic tubercle is associated with narrow origin of internal oblique muscle from lateral inguinal ligament. MATERIAL & METHODS: Hospital based case -control study was carried out at tertiary care institute on 135 admitted patients with inguinal hernia in Surgery department, form Nov. 2010 to Dec. 2011 and the same number of age matched volunteers not having inguinal hernia(IH) were taken as control. Various anatomical and anthropometric measurements were recorded. RESULTS: Right sided IH was more common 59.25%.And most of them were direct IH 94.5%. Weight, SS line and ST line showed significant difference among cases and control. CONCLUSION: The present study undoubtedly shows that the number of, muscle and connective tissue variations in inguinal region depends upon the position of the groin in relation to the interspinal plane which increases the risk of IH.

KEYWORDS: Anatomy, height, Inguinal Hernia, Pubic tubercle, Weight.

INTRODUCTION: The word "hernia" is a Latin term that means "rupture" of a portion of structure. This word in Greek means "bud". Hernia by definition is the abnormal protrusion of any viscus or peritoneum -lined sac outside of its normal containing cavity through some natural or unnatural opening. Fundamentally, all sites of herniation possess one feature in common i.e. the zone of weakness where structures pass from or to the abdominal cavity or where interstices occur between musculoaponeurotic bands of surrounding trilaminar wall. All the hernias in groin begin within a single weak area called myopectoneal orifice.¹ Lack of the evolutionary development of a strong posterior rectus sheath and transversalis fascia in lower abdomen is thought to represent a significant specific anatomic defect in the evolution of humankind.² There are various contributing and precipitating factors like chronic constipation, chronic cough, senile enlargement of prostate (all Increasing intra-abdominal pressure) and obesity. The lowness of pubic tubercle is associated with narrow origin of internal oblique muscle from lateral inguinal ligament. The narrow origin of internal oblique muscle fails to protect the deep right and consequently indirect inguinal herniation occurs. Novarro et al (1992)³ undertook study in 156 cases of inguinal hernia; they measured distance of pubic tubercle from a horizontal line joining both the anterior superior iliac spines and compared the results with twenty healthy volunteers. The distance of the pubic tubercle from bi-crestal horizontal line was more than 7.0 cm in patients having inguinal hernia as compared to the volunteers who had less distance. The present study was undertaken to evaluate the role of low lying pubic tubercle in the development of inguinal hernia.

MATERIAL AND METHOD: After the institutional ethic committee permission, the present case control study was carried out in one of the tertiary care institute in central India. One hundred and thirty five cases of inguinal hernia resenting in surgical OPD and wards of Our medical college hospital from Nov. 2010 to Dec. 2011 and the same number of age matched volunteers not having inguinal hernia were taken as control, were included in the study.

Selection of the Cases and Controls: Any case of inguinal hernia irrespective of sex and occupation were included in the study, (excluding the patient who have obvious associated causative factor for hernia Urinary Outflow Obstruction etc.). However children below the age of 16 yrs. were excluded from the study as the pelvis is not fully developed before this age & exact position of pubic tubercle cannot be forecasted due to the growth of skeletal system. Controls for the study were formed by the volunteers of the same age group (>16 yrs.) who do not have inguinal hernia. Controls having any pelvic fracture or anomaly were also excluded from the study by taking relevant history and doing +through examination. A detailed history of presenting complaint of the study subjects related contributory and precipitating factors leading to the development of inguinal hernia were taken. Through physical examination was done to know the type of hernia. Routine investigation and other particulars relating to patient were noted height, weight & built of the patient also noted.

Measurements: The study subjects were asked to lie in supine relaxed position on hard bed. Keeping both their lower limbs straight, so that both the anterior superior iliac spine were at the same level. A line was drawn on the anterior abdominal wall. Connecting both anterior superior iliac spine which was given the name SS Line and the length of SS Line was noted; next the pubic tubercle on the side of hernia was marked by the palpation. Then vertical distance between this point and the SS Line was measured in centimeters. This line was designated as ST line. Similar measurement was done on controls as well.

Data Analysis: The data collected was entered in to Microsoft office excel 2007. An attempt was made to find any relationship between ST Line and SS Line measurement and height, weight, built, occupation and age with side of hernia of the patient. The ST and SS Line measurements of the case were compared with those of controls to find out whether there is tendency of having low lying pubic tubercle in case of inguinal hernia. An attempt was also made to observe any correlation between ST segment and height, weight of the patients. The quantitative variables were summarized as mean and standard deviation while qualitative variables as percentage and proportion. To the statistical significance between the two independent two groups student‘t’ test while in more than two groups ANOVA (one way) was applied and to show correlation Pearson’s correlation was applied. The difference was considered significant when p value was less than 0.05.The statistical package used was SPSS 17.

Observations: A total of 135 cases and 135 age and sex matched controls were included in the study. Out of total 135 cases, mostly 80(59.25%) were right sided hernia, 36(26.68%) were left sided and 19(14.07%) were bilateral i.e. 38 hernia. A total 116 cases were having unilateral hernia (i.e. either right or left). Out of these 116 cases, only 18(15.5%) were direct and 98(94.5%) were indirect while 54 (46.5%) were complete and 62(43.5%) were incomplete. Nineteen cases were found to have bilateral hernia i.e. 38 hernia. Out of these bilateral inguinal hernia 12(31.6%) were complete and rest 26 (68.4%) were of incomplete type including 4 recurrent hernia on one side. Table no. I it was evident that the side of hernia had no relation with the weight, height and SS or ST line measurements as there was no significant difference between the mean values of different parameters in three groups of cases according to the diagnosis (p>0.05). Maximum numbers of cases were in age group 46-55 years. Mean age of patients with direct hernia was 61.23± 12.3 years and that of patients with indirect hernia was 48.19 ± 11.3 years. Apparent etiological factors detected in 17 cases (Table no. II), rest 118 patient (88.14%) of hernia were spontaneous in nature. 28(20.7%) cases of inguinal hernia had presented with complications. 06(4.4%) hernias were irreducible without features of intestinal obstruction. 12 (8.9%) cases had presented with obstruction. Table no. III shows difference between the mean values in cases and control. Taking 7.5 cm as an arbitrary cut off value for ST segment, it was observed that 82.22% of the cases in study group had ST segment value more than 7.5 cms. Out of this 50% of cases in study group had ST segment value more than 9cms. In contrast only 17.77% of the control group had ST segment value more than 7.5 cms (Table IV).

DISCUSSION: The inguinal hernia is the commonest, followed by femoral, umbilical and incisional hernia. Inguinal hernia is much more common in males as compared to females.⁴ In the present study, no female case of inguinal hernia was seen. Our study observed 59.25% cases were having right sided inguinal hernia. Normally right sided inguinal hernias are more common. This is because of deferred descent of right testis. As supported by other studies.⁴ Presence of a preformed peritoneum lined sac is considered to be a factor in the development of inguinal hernia. However, only two out of 135 cases in the present study had patent processus vaginalis. This indicates that patent processus vaginalis is not the only prerequisite to the development of inguinal hernia in adults.⁵ In the present study it was observed that 82.19 % of cases in the study group had ST line measurements more than 7.5 cms even >50% of cases in same group had ST measurement >9.0 cm however, only 18% of subjects in control group had ST line measurements more than 7.5 cms. Only 2 subject had >9 cms ST line measurement in control group. Hence the present study undoubtedly shows that the number of, muscle and connective tissue variations in inguinal region depends upon the position of the groin in relation to the interspinal plane. Similar finding was observed by McVay CB et al (1971)⁶ and Novarro et al (1992)³ that European subjects having inguinal hernia have much low lying public tubercle as compared to the controls not having inguinal hernia. Feasibility of correlation between the measurements of ST line with weight and height was found out by calculating the values of correlation co­efficients. A positive correlation was found between weight and ST line (r=0.0975) while (r=0.0384) between height and ST line. Similar finding has been revealed by a case control study by Ledinsky et al (1998)⁷, Ajmani ML et al (1983) ⁸ and others.^{9, 10}

The present study undoubtedly shows that the groups of persons with low lying pubic tubercle are at a higher risk of developing inguinal hernia. The identification of structural characteristics of the inguinal region therefore enables the selection of the most appropriate operation procedure, i.e. between the classic hernia repair and prosthetic mesh implant. In patients with low lying pubic tubercle, the gap between lower border of musculoaponeurotic arch and inguinal ligament is greater. Therefore, a classic hernia repair in such patients will not be possible without undue tension, thus increasing the chances of recurrence following repair. So by identifying the anatomy of the inguinal region, we can preoperatively plan about the type of repair to be done.

Patient undergoing herniorrhaphy have the right to assume that the repair will last for the rest of their life: This is the least that they can expect from the surgeon. It is the surgeon's responsibility to rise to these expectations as the factors that bring about recurrence of groin hernia (which is 1-2% in specialized center) after failed attempts at repair are almost universally controllable by relatively simple means i.e. proper selection of repair technique. In low constituted ingunal region there may be high arched myoaponeurotic upper border with wide gap between conjoined tendon and the inguinal ligament or pectineal ligament which creates tension, tissue necrosis with separation of sutured tissue and repeated recurrence of hernia in conventional repair (Abhramsons). In our study 7 patients presented with recurrent hernia as complicated cases all have undergone conventional hernia repair previously has mean value of ST segment is 9.57 ±0.83 cm which was more than observed values of study group which suggest that low lying pubic tubercle should have association between recurrence of hernia following conventional repair.

CONCLUSION: It could be concluded that low lying pubic tubercle is associated with abnormal origin and insertion of internal oblique and transversus abdominis muscles and thus resulting in an ineffective shutter mechanism of inguinal canal leading to increased risk of inguinal hernia development, especially in the presence of other risk factors.

REFERENCES:

1. Fruchand H. Anatomie Chirurgicale des Hernies de 1'Aine, proceeding of the Royal society of Medicine. Paris G. Doin. 1956.
2. McArdle G. Is inguinal hernia a defect in human evolution and would this insight improve concepts for methods of surgical repair? Clin. Anal, 10(1):47-55, 1997.
3. Navarro S, Calabuig R, Lopez JL et al. Low tuberculum pubis predisposes to inguinal hernia. British Journal of surgery 1992; 79:S56
4. Van KJP, Simons MP, Plaisier PW, Lange JF. The etiology of indirect inguinal hernias: congenital and /or acquired? Hernia 2003;7: 76-79
5. Kahn AM, Hamlin JA, Thompson JE. The etiology of adult indirect inguinal hernia: revisited. Am Surg 1997;63(11):967-9,
6. McVay CB. The normal and pathologic anatomy of the transversus abdominis muscle in inguinal and femoral hernia. Surg Clin North Am, 51:1251, 1971.
7. Ledinsky M, Matejic A, DeSyo D. Some structural characteristics of inguinal. Region in Northern Croatia. Collegicum anthropologicum (Zagreb) 1998 Dec;22(2):515-24.
8. Ajmani ML, Ajmani K. Anatomical basis for the inguinal hernia. Anat Anz. 1983;153(3): 245-8.
9. Gilbert I. An anatomic and functional classification for the diagnosis and treatment of inguinal hernia. The American Journal of Surgery 1989; 157(3): 331-333
10. Peacock EE, Madden JW. Studies on the biology and treatment of recurrent inguinal hernia II. Morphological changes. Ann Surg. May 1974; 179(5): 567–571.

RIH = Right Inguinal Hernia, LIH = Left Inguinal Hernia, B/LIH = Bilateral Inguinal Hernia, D= Direct, ID= Indirect, M= Mixed

* * p<0.01 *p< 0.05 N=250, DF = N-2