Inguinal Hernia: classification, diagnosis and treatment--classic, traumatic and Sportsman's hernia

Inguinal hernia repair is performed in more than 600,000 cases every year in the United States. However, the true prevalence may be even higher. Many groin hernias are not diagnosed, e.g., Sportmans' hernia, or are asymptomatic. The etiology of classic inguinal hernia, Sportsman's hernia or traumatic hernia may be different. The hernia repair is performed in agreement with a classification of the hernia, e.g., Nyhus classification. According to recent randomized controlled trials and meta-analyses open-mesh repair demonstrates several advantages in comparison to laparoscopic procedures. Laparoscopic procedures require more time and cost more, show a potential for serious complications and may be followed by an increased rate of recurrence. There may be a faster reconvalescence after laparoscopic procedures. However, there may be also a selection bias. Laparoscopic procedures are associated with specific complications, e.g., pneumomediastinum, pneumothorax, gas extravasation, trocar injuries, intraabdominal adhesions, bowel obstruction, which are rarely or never seen in open-mesh repair. In the United States we could observe an uncoupling of hernia repair from classification. In more than 90% of cases the treatment was open-mesh. In many hernia studies the hernias were classified as direct or indirect, primary or recurrent. The existing classifications are based on anatomical findings in relation to the development of the hernia: posterior floor integrity, enlarged interior ring and size of the hernia. However, the size of the hernia may not always be associated with the severity of the hernia and it may be difficult to estimate. The outcome of hernia repair may be influenced by other factors. There may be differences in the presentation of the hernia to the surgeon based on the damage done to the surrounding tissue in the inguinal canal, e.g., external ring, aponeurosis of the external oblique, inguinal ligament, which is most often accompanied by severe adhesions. Further factors influencing outcome of hernia repair may be patient-related factors, e.g., constipation, ASA classification, diabetes, smoking. A classification should be simple to use and easy to remember: (A) indirect hernia, (B) direct hernia, (C) scrotal or giant hernia, (D) femoral hernia. A and B can be classified as (0) uncomplicated, (1) posterior floor defect, (2) posterior floor defect plus defect in the anterior part of the inguinal canal. All four types (A-D) may be either primary or recurrent. In this classification combined femoral, indirect and/or direct hernias can be categorized by using the types A, B, C, or D as in a modular construction system. The category "other" is reserved for rare types of hernia, e.g., obturator hernia, Spieghelian hernia. Aggravating factors are included: Diabetes, obesity, age above 65, constipation, ASA III or more and cigarette smoking. This classification may be helpful to evaluate outcome of hernia repair with regard to patient related factors and the increased demands for the surgeon and the staff. In some health care systems the general belief is that all hernias are equal and be managed equally. However, groin hernias may be complex and need individual treatment.