What is an inguinal hernia?
An inguinal hernia is a swelling in the groin caused by contents in the tummy passing through a weakness between the muscle layers in the groin. Inguinal hernias are common.
What causes an inguinal hernia?
Passing between the muscles in the groin is a narrow passage called the inguinal canal. In boys, this canal contains blood vessels going to and from the testicle together with the tube that transmits sperm from the testicle (the vas). In girls, the canal contains a small ligament only. In both sexes, the canal also contains a thin tube-like extension of the lining of the inside of the tummy (which looks like ‘Gladwrap’). This tube typically closes soon after birth but if it remains open, it forms a track through which a content of the tummy (such as bowel) can enter the inguinal canal and cause a lump in the groin.
Inguinal hernias are more common in boys and premature babies. They often affect one groin only but may affect both (bilateral).
Can an inguinal hernia get better without an operation?
No. The swelling in the groin often comes and goes at first but once a hernia is present, it does not go away. Surgery is the only way to fix it.
Why does an inguinal hernia have to be repaired?
Inguinal hernias get gradually bigger with time. The main reason they need to be repaired is to avoid a loop of bowel or another structure from inside the tummy getting stuck in the hernia; this can block the bowel and cut off its blood supply (called a strangulated hernia) making the child seriously ill. A painful hernia or one which becomes hard and tender needs urgent medical review, as these signs suggest that something may be stuck in the hernia.
What does the operation involve?
An inguinal hernia is usually repaired under a general anaesthetic. Once your child is ‘asleep’ the surgeon makes a small cut in a skin crease in the groin and finds the hernia ‘sac’ (the thin tube-like extension of the lining of the tummy). In a boy, the sac must
be separated from the testicular blood vessels and the vas. The sac is tied off with thread. The skin is closed with dissolving stitches and a dressing put on the wound. A local anaesthetic is often injected during the operation to reduce wound soreness.
Repair of a hernia on one side usually takes about 15-20 minutes. Your child will be in the operating theatre for longer because it takes time to safely put him/her to sleep and to wake them from the anaesthetic. After the operation he/she will be transferred to a recovery area where you will be able to join them.
Are there any complications of the operation?
Repair of an inguinal hernia is a common and straightforward operation but any operation has a risk of complications. Fortunately, these are uncommon.
- Complications of the anaesthetic.
Your anaesthetist is the best person to discuss these.
2. General complications of any operation. Bleeding is rare but temporary bruising of the wound or scrotum occurs occasionally. A wound infection is uncommon but you should see your family doctor if the wound becomes red or increasingly painful in case your child needs treatment with
- Specific complications of the operation:
- A fluid swelling around the testicle (called a hydrocele) may develop after the operation; it usually disappears gradually by itself.
- A recurrent hernia happens in less than 1% of children but is slightly more frequent after hernia repair in a newborn baby. A recurrent hernia has to be treated by a further operation.
- Damage to nearby structures during the operation including the contents of the hernia (such as the bowel or, in girls, the ovary), nerves (causing temporary numbness of a patch of groin skin), or the blood vessels or vas connected to the testicle. Damage to the latter can cause the testicle to shrink and impair sperm production; fertility then depends on whether the other testicle works normally.
- The testicle on the side of the hernia repair occasionally comes to lie nearer the groin after a hernia repair, needing a subsequent operation to bring it down to the scrotum.
When will my child be able to go home after the operation?
In older infants and children, the operation is carried out as a ‘day case’ so that your child is able to go home later the same day. You will be advised to give him/her regular doses of a painkiller such as Paracetamol during the first 24 hours after the operation.
Infants under about 3 months of age (or older if the baby was premature), often need to be monitored in hospital for one night after the operation before going home or back to their referring hospital.
When can my child resume normal activities?
Children recover rapidly after an inguinal hernia repair. They can have a quick bath or shower the next day. The dressing can be peeled off if it is still on after a week or left to fall off on its own. Older children can usually get back to school after a couple of days and resume sports about 2 weeks after the operation. The general rule is “if it hurts, stop and wait longer before trying again”.