Chapter 37: Inguinal Hernias
The incidence of inguinal hernias in men has a bimodal distribution, which peaks
A. Before the second year of life and after age 50.
B. Before the first year of life and after age 40.
C. Before the eighth year of life and after age 40.
D. Before the fifth year of life and after age 50.
Approximately 75% of abdominal wall hernias occur in the groin. The lifetime risk of inguinal hernia is 27% in men and 3% in women. Of inguinal hernia repairs, 90% are performed in men and 10% in women. The incidence of inguinal hernias in men has a bimodal distribution, with peaks before the first year of life and after age 40. Abramson demonstrated the age dependence of inguinal hernias in 1978. Those between ages 25 and 34 years had a lifetime prevalence rate of 15%, whereas those aged 75 years and over had a rate of 47% (Table 37-1). Approximately 70% of femoral hernia repairs are performed in women; however, inguinal hernias are five times more common than femoral hernias. The most common subtype of groin hernia in men and women is the indirect inguinalhernia. (See Schwartz 10th ed., p. 1495.)
Table 37-1 Inguinal hernia prevalence by age
|Age (y) ||25–34 ||35–44 ||45–54 ||55–64 ||65–74 ||75+ |
|Current prevalence (%) ||12 ||15 ||20 ||26 ||29 ||34 |
|Lifetime prevalence (%) ||15 ||19 ||28 ||34 ||40 ||47 |
The two types of collagen found to exist in a decreased ratio of the skin of inguinal hernia patients are
Epidemiologic studies have identified risk factors that may predispose to a hernia. Microscopic examination of skin of inguinal hernia patients demonstrated significantly decreased ratios of type I to type III collagen. Type III collagen does not contribute to wound tensile strength as significantly as type I collagen. Additional analyses revealed disaggregated collagen tracts with decreased collagen fiber density in hernia patients’ skin. Collagen disorders, such as Ehlers-Danlos syndrome, are also associated with an increased incidence of hernia formation (Table 37-2). Recent studies have found an association between concentrations of extracellular matrix elements and hernia formation. Although a significant amount of work remains to elucidate ...