Malrotation of the Intestine

Also known as: Intestinal malrotation

Intestinal malrotation results from abnormal embryological rotation and fixation of the midgut.

The clinically dangerous consequence is formation of an abnormally narrow mesenteric base, allowing the entire midgut to twist around the superior mesenteric vascular pedicle.

Abnormal peritoneal bands, termed Ladd bands, can extend from an abnormally positioned caecum across the duodenum and produce extrinsic duodenal obstruction.

The bowel is typically positioned abnormally:

Small bowel predominantly right sided
Colon predominantly left sided

The exact positional abnormality is less important than the narrow mesenteric pedicle and risk of midgut volvulus.

In a neonate or infant, the most important presentation is:

Bilious vomiting.

Bilious vomiting in a newborn must be treated as intestinal obstruction until proven otherwise.

Malrotation without volvulus can produce:

Intermittent bilious vomiting
Feeding intolerance
Episodic abdominal pain
Poor growth
Chronic obstructive symptoms

Older children can present with nonspecific recurrent abdominal pain.

Sudden severe pain, abdominal tenderness, haematochezia or shock suggests volvulus with intestinal ischaemia.

A plain abdominal radiograph can be normal and does not exclude malrotation or volvulus.

Upper gastrointestinal contrast study: standard anatomical investigation in a stable infant; determine whether the duodenojejunal junction is abnormally positioned and whether there is evidence of twisting.

Ultrasound can demonstrate abnormal superior mesenteric artery and vein relationships or a whirlpool of mesenteric vessels, but a normal vascular orientation does not reliably exclude malrotation.

When the infant has bilious vomiting plus peritonitis or physiological deterioration, diagnostic imaging should not delay urgent surgical exploration.

Symptomatic malrotation

Definitive treatment is the Ladd procedure.

The operation consists of:

Inspect for volvulus
Detorse volvulus counterclockwise if present
Divide obstructing Ladd bands
Mobilise duodenum sufficiently
Broaden the mesenteric base from the duodenum to the caecal region
Position small bowel broadly on the right
Position colon broadly on the left
Perform appendicectomy in most conventional procedures

The objective is not restoration of normal embryological rotation. The objective is creation of a broad mesenteric base that cannot easily twist.

Appendicectomy avoids future diagnostic confusion because the caecum remains abnormally positioned after the operation.

Laparoscopic versus open

Laparoscopic Ladd procedure is suitable for selected stable patients without major bowel distension or ischaemia.

Open laparotomy remains preferable with:

Haemodynamic instability
Established midgut volvulus
Severe bowel distension
Suspected necrosis
Need for rapid full bowel assessment

Recent comparative data support laparoscopic treatment in appropriately selected children, although recurrent volvulus remains a concern if the mesenteric base is not broadened adequately.

Incidental malrotation

Management of completely asymptomatic malrotation discovered later in childhood is less straightforward.

In infants and young children, many surgeons favour Ladd correction because catastrophic volvulus cannot be predicted reliably.

In older asymptomatic patients, operative risk and lifetime volvulus risk should be individualised.

Postoperative complications

Important complications are:

Adhesive small bowel obstruction
Recurrent volvulus
Persistent dysmotility
Short bowel syndrome if previous volvulus damaged bowel

Recurrent bilious vomiting after a previous Ladd procedure must still be evaluated urgently because recurrent volvulus is uncommon but possible.

Clinical toolsCalculators

BMI GCS EDD Parkland Formula

Corrected Sodium Corrected Calcium Anion Gap Creatinine Clearance Insulin Calculations qSOFA Wells PE Wells DVT CHA₂DS₂-VASc HAS-BLED CURB-65 Centor/McIsaac

Undescended Testis

Also known as: Cryptorchidism

Undescended testis, or cryptorchidism, occurs when one or both testes fail to reach the dependent scrotum.

The testis may lie:

Intra abdominal
Within the inguinal canal
At the external ring
Prescrotal

An ectopic testis has left the normal path of descent and may lie in the superficial inguinal pouch, perineum, femoral region or another abnormal position.

A retractile testis can be manipulated into the scrotum without tension and remains there temporarily. It is not a true undescended testis but requires surveillance because secondary ascent can occur.

Longstanding cryptorchidism is associated with:

Progressive germ cell loss
Reduced fertility potential
Testicular malignancy
Torsion
Associated inguinal hernia

Spontaneous descent after approximately 6 months corrected age is uncommon.

Examine in a warm room with the child relaxed.

Palpate from the anterior superior iliac spine toward the scrotum.

Classify as:

Palpable
Nonpalpable

A nonpalpable testis can represent:

Intra abdominal testis
Canalicular testis not appreciated clinically
Atrophic testicular remnant
Absent testis

Bilateral nonpalpable testes

This requires urgent assessment for a disorder of sex development, particularly when associated with:

Hypospadias
Micropenis
Ambiguous genitalia

Do not assume the child is simply a routine bilateral cryptorchid case.

Timing

If the testis remains undescended at 6 months corrected age, plan surgery.

Perform orchiopexy ideally between 6 and 12 months, and by 18 months at the latest. Earlier orchiopexy preserves germ cell potential better than delayed treatment.

Hormonal therapy should not be used routinely simply to induce descent of a unilateral undescended testis.

Palpable inguinal testis

Perform inguinal orchiopexy.

Key steps:

Mobilise the testis and spermatic cord
Divide restrictive cremasteric fibres
Identify and ligate a patent processus vaginalis
Mobilise cord sufficiently to obtain tension free scrotal placement
Create a subdartos pouch
Place the testis in the dependent scrotum without torsion

Do not stretch the testicular vessels excessively merely to reach the scrotum.

A low palpable testis can sometimes be treated through a single scrotal approach.

Nonpalpable testis

Perform examination under anaesthesia followed by diagnostic laparoscopy if still nonpalpable.

Possible findings include:

Blind ending vessels

Suggest vanishing testis.

Vas and vessels entering the internal ring

Explore the inguinal canal for a testis or remnant.

Intra abdominal testis

Management depends on distance from the internal ring and vascular length.

Low intra abdominal testis

When adequate vessel length exists, perform primary laparoscopic orchiopexy while preserving the native spermatic vessels.

High intra abdominal testis

When the testis cannot reach the scrotum on intact vessels, options include a Fowler Stephens strategy.

Two stage Fowler Stephens

Stage 1:

Divide the testicular vessels while preserving collateral flow from:

Deferential artery
Cremasteric vessels

Allow collateral circulation to develop.

Stage 2:

Approximately 6 months later, mobilise the testis into the scrotum.

Two stage treatment has a lower reported atrophy rate than one stage vessel division.

Preserving the gubernacular blood supply where feasible can further protect perfusion.

Testicular remnant

A clearly atrophic nonfunctional nubbin can be excised, particularly if intra abdominal.

Postpubertal undescended testis

Management changes after puberty.

A postpubertal intra abdominal testis with a normal opposite testis frequently undergoes orchiectomy because fertility benefit from orchiopexy is minimal while cancer risk remains significant.

Long term follow up

Orchiopexy reduces but does not eliminate future malignancy risk.

Teach testicular self examination after puberty.

Monitor for:

Reascent
Testicular atrophy
Hernia
Fertility problems, particularly bilateral disease

Malrotation of the Intestine

Overview

Clinical Features

Diagnosis

Management

Overview

Clinical Features

Diagnosis

Management