Malrotation describes a wide range of anatomical variants of an intestinal position anomaly characterized by disturbed intestinal rotation and intestinal adhesions during pregnancy (embryonic development).

During pregnancy, the fetal intestine moves into the umbilical cord for a few weeks (4th-10th week) in order to grow in length outside the narrow abdominal cavity. After re-entering the abdominal cavity, the intestine then normally rotates 270° anti-clockwise around the vascular axis, with subsequent attachment of certain parts of the intestine to the posterior abdominal wall.
If there is a disturbance in the rotation of the intestine when the intestinal loops retract into the abdomen and a lack of attachment of parts of the intestine to the posterior abdominal wall, there are so-called positional anomalies of the intestine. Depending on their severity, different forms are distinguished:

Incomplete rotation: Any rotation of less than 270° (counterclockwise)

Non-rotation: This form occurs when there is no further rotation during embryonic development when the intestine re-enters the abdominal cavity around the 10th week of pregnancy.

Reverse rotation: An abnormal clockwise rotation occurs.

Mobile cecum: Parts of the large intestine are not attached to the posterior abdominal wall; instead, anterior parts of the small intestine are attached.

The exact frequency of malrotations is unknown, as not all forms lead to clinical symptoms and are detected. This also applies to pronounced malrotational malformations, which can occasionally remain asymptomatic. Malrotational malformations with clinical symptoms occur in one in 6000 live births.

Malrotation is regularly found in some diseases of the newborn. These include congenital diaphragmatic hernia or certain abdominal wall defects (gastroschisis, omphalocele). However, malrotation can also occur in isolation. In addition to the asymptomatic course, malrotation can also be the cause of acute intestinal torsion (volvulus), which mainly occurs in early infancy and in which the small intestine rotates around the blood vessels supplying the intestine due to a lack of adhesion to the abdominal wall. As a result, the affected sections of the intestine have a reduced blood supply with the risk of permanent intestinal damage. For this reason, the clinical picture of volvulus is a pediatric surgical emergency that must be clarified immediately. Any infant with bilious vomiting, restlessness and a deterioration in general condition must always be considered for acute intestinal torsion (volvulus).

Due to the possible severity of the clinical picture, if volvulus is suspected, either a comprehensive diagnosis is made immediately or, in case of doubt, immediate surgery is performed. The principle applies that an infant with bilious vomiting has malrotation/volvulus until proven otherwise.

Omphalocele occurs in 1:5000 children, boys are more frequently affected than girls. It is not hereditary and there is therefore no higher risk for other children of the same mother. Ultimately, the cause of omphalocele is still unclear. Children with omphalocele often have other malformations, e.g. of the heart, kidneys or intestines. The prognosis usually depends on the accompanying malformations and the size of the abdominal wall defect. Children with prenatally known omphalocele should therefore be born in a center with well-founded neonatological and pediatric surgical expertise.

Treatment is usually surgical and consists of moving the contents of the hernia sac back into the abdominal cavity. For small omphaloceles, this can be done as a primary closure. In the case of large defects, the treatment strategy must be determined on a case-by-case basis.

If the clinical condition of the child allows it and this does not waste time unnecessarily, an X-ray examination of the abdomen is carried out, in which the intestine is filled with contrast medium via the mouth (so-called gastrointestinal passage or "MDP"). An ultrasound of the abdomen can also be performed. The anatomical position of the large abdominal vessels can provide initial indications of an anomaly in the position of the intestine. However, even if there is only the slightest doubt, the abdominal cavity must be examined as part of a surgical procedure (laparotomy).

Emergency surgery
If the examinations confirm the suspicion of acute intestinal torsion or if this cannot be ruled out, the indication for immediate surgery is discussed with the parents. A transverse abdominal incision is made to gain access to the abdominal cavity. In the next step, the entire bowel is examined for a twist. If a volvulus is found, the intestinal torsion is "untwisted" and the affected section of intestine is examined for signs of sufficient blood flow. If the intestine is already irreversibly damaged, the affected section may have to be removed. Depending on the extent of the damage, the remaining sections of bowel are connected together or drained via an artificial anus.

 

Planned (elective) surgery: release of the Ladd's ligaments
Malrotation causes strands of connective tissue, the so-called Ladd's ligaments (named after the American pediatric surgeon William Ladd (1880-1967)), to form between the appendix (cecum), which is located in the upper right abdomen (and not normally in the lower right abdomen), and the lateral abdominal wall. These connective tissue cords lead to a narrowing of the duodenum (Fig. 1), which can lead to recurrent bilious vomiting. During an operation, which can be performed openly (laparotomy) or via laparoscopy, these Ladd's ligaments are located and severed, allowing the intestine to assume a more "relaxed" position (small intestine on the right and large intestine on the left in the abdomen in the sense of non-rotation) and the duodenum to pass freely again. The appendix of the appendix is usually also removed during this procedure.

Children with malrotation who have undergone emergency surgery must remain in hospital for several days after the operation. During this time, the child and mother are cared for by our pediatric nurses and medical team on the infant ward (or pediatric surgery ward depending on age). In the first few days after the operation, your child will not be fed via the mouth or the feeding tube, but via a central access through the blood vessels. The feeding tube will remain in the child's stomach for a few days after the operation. This is necessary in order to drain the secretions (saliva, gastric juice, small intestinal secretions) that cannot yet pass easily through the small intestine due to temporary swelling and the general sluggishness of the small intestine after the abdominal operation.

A few days after the operation, your child can be fed by mouth. However, it is not possible to predict how long it will take for the bowel to function normally. Every child takes its own time. If your child drinks the food completely and gains weight steadily, he or she is healthy and can be discharged home.

Children with malrotation who have undergone elective (planned) surgery due to malrotation without volvulus will initially remain in the recovery area after the operation, where you will be able to sit at the bedside again. You will then be transferred to the normal ward. However, how long it takes until your child can eat again varies greatly from person to person.

Due to the wide variation in the spectrum of illnesses and clinical progression, it is not possible to predict when, how often and where the first post-operative check-ups will take place after discharge. However, they are usually carried out by your pediatrician. However, if any questions remain unanswered or if we consider an earlier follow-up examination to be appropriate in individual cases, you can come back to us at any time.

In both primary closure and delayed (secondary) closure, children are usually not fed by mouth (enteral) in the first few days and receive the required fluids via a drip (venous access, intravenous). After the procedure, a tube is left in place, which is inserted via the nostril into your child's stomach and drains the digestive juices.

During this time, the child and mother are cared for by our pediatric nurses and medical team on the infant ward. When the digestive juices are transported from the intestines and your child has a bowel movement, we start to feed your child by mouth. However, it is not possible to predict how long it will take for the bowel to function normally. Every child takes its own time. However, full enteral feeding is typically delayed in children with omphalocele (several days to weeks from surgery to full feeding).
When your child is drinking the food completely and gaining weight steadily, the feeding tube will be withdrawn and you can be discharged home.

Due to the great variability of the disease spectrum and clinical course, it is not possible to predict when, how often and where the first post-operative check-ups will take place after discharge. They are usually carried out by your pediatrician, but we will also visit you at regular intervals in our pediatric surgery outpatient clinic.