Malrotation
Key points
1 in 6-7000 live births - but possibly up to 1% of population
75% of patients present in 1st month of life, 15% in 1st year
Gut embryology: Primitive intestinal tube - 4 stages: 1. Herniation 2. Rotation 3. Retraction 4. Fixation
Normal rotation: 270 degrees counterclockwise
Non-rotation: Rotation arrested at 90 degrees counterclockwise -
Reverse Rotation: First 90 degrees occur normally clockwise. The next180 degrees occur clockwise. Net 90 degrees clockwise rotation
Classic malrotation: Rotation of gut arrested after the first 90 degrees counterclockwise but not completing the reminder of the 180 degrees
Paraduodenal hernias occur because mesocolon does not fuse to posterior wall and a space is created - can obstruct
Chilaiditis syndrome - Colon is over top of liver and pinches, causing pain
2 fixed points in all variants are pylorus and splenic flexure
Non-rotation
The intestines fail to rotate beyond the initial 90 degrees counterclockwise
The small bowel remains on the right side, and the colon remains on the left side of the abdomen
The terminal ileum enters caecum from the right side
Associated with CDH, Exomphalos, Gastroschisis
After Ladd’s procedure, deliberately placed position
May be asymptomatic and found incidentally
Lower risk of volvulus because the mesentery is wider
May cause chronic symptoms like bloating or intermittent obstruction if adhesions form
Can be associated with internal hernias
Internal Hernias
Right and Left paraduodenal hernia
Mesocolic Hernia
Peritoneal/Omental Hernia
Reversed Rotation of Bowel
First 90 degrees counterclockwise
Followed by 180 degrees Clockwise
Net 90 degrees clockwise
The transverse colon lies behind the SMA
SMA is between transverse colon behind and Duodenum in front
Duodenum in front of Transverse colon and SMA
Caecum is in the midline
Can cause Ileocecal volvulus, transverse colon obstruction from SMA and duodenum, duodenal obstruction
Malrotation
Counterclockwise rotation arrested between 90 and 270 degrees
Results in:
Short mesentery causing acute and chronic/intermittent volvulus
Ladd’s Bands causing acute and chronic duodenal obstruction
Age of presentation:
First month: 75%
First year: 90%
However, presentation can occur at any age
Associations
Duodenal and Intestinal Atresia
Anorectal malformations
Cardiac anomalies
Trisomy 21
Prune belly syndrome
If patient has ARM - do not take appendix in Ladd's procedure in case needs ACE
For (probably) non-rotated patients, risk of volvulus with gastroschisis is 1%, exomphalos 3% (Fawley et al, 414 patients)
Presentation
Sudden onset of bilious vomiting in a healthy child
Early - scaphoid abdomen
Later - progressive distension + discolouration, bleeding PR, hypovolemia, acidosis, shock
Chronic obstruction - failure to thrive (protein-calorie malnutrition due to venous and lymphatic obstruction), vomiting
Investigations
The most common finding on plain film of a patient with malrotation is “normal bowel gas pattern”
UGI contrast - the investigation of choice: position of DJ, level of DJ, Corkscrew/coilspring appearance if volvulus
Lower GI contrast - position of caecum
USS - Inversion of SMA/SMV i.e. SMV lying either anterior to or left to the SMA
CT - usually in adult practice, swirl or 'whirlpool' sign for mesenteric vessels
If on UGI contrast the DJ flexure is not at same level (equivocal study) risk of volvulus is low
In some cases where the diagnosis is uncertain, a contrast enema can be used to visualise the position of the caecum - from this the width of the mesentery can be estimated
With volvulus, the lactate may be normal if there is complete venous outflow obstruction from the ischaemic segment, isolating it from the systemic circulation
Operative management
Right Upper Transverse Incision
Completely eviscerate the bowel and mesentery
Confirm the diagnosis - if volvulus - will just see small bowel on entry to abdomen, may see chyle
Prepare for reperfusion syndrome - warn anaesthetist due to release of ischaemic products into circulation, wait 15 minutes (hypotension, hyperkalemia, lactic acidosis )
Untwist the bowel counter-clockwise ('turn back the clock') - must be able to see transverse colon at end
Good oxygenation, warmth and hydration
Reinspect the bowel
Resect necrotic bowel
Primary anastomosis or damage control surgery
Ladd’s Procedure: Division of Ladd’s bands
Straightening of the duodenum
Splaying (widening) of mesentery
Always put down OG tube to check for duodenal web
Appendicectomy
Return bowel in non rotated position
Removal of appendix during Ladd’s procedure:
Advantages: Removes risk of appendicitis - diagnostic uncertainty, delay, complications of the disease and the procedure
Appendicular vessels may have been damaged during Ladd’s procedure
Uses of Appendix:
Mitrofanoff
ACE procedure
Reservoir of beneficial microbiota
Presence of gut-associated lymphoid tissue
Stem cell reservoir in which mesenchymal stem cells have been identified and isolated from human vermiform appendices
After appendicectomy, alteration of the gut microbiota into a less diverse microbiome which is theorised to increase risk of gastrointestinal cancer, rheumatoid arthritis, sarcoidosis, Parkinson’s disease, pyogenic liver abscess, and gallstones
If reversed rotation - call colleague - mobilise colon and pass under SMA and duodenum. Difficult to do colo-colic anastomosis on unprepared bowel
If pre-duodenal portal vein found, perform duodenoduodenostomy - do not divide as it may be only drainage of gut
Post operative complications
Mortality 3-9%
Short bowel syndrome
Recurrent volvulus (1-8%)
Chylous ascites
Post op intussusception (on day 5) 3%
Adhesive SBO requiring operation 10%
Standard scenario
Neonate with bilious vomits/other signs of volvulus
Resuscitation and gas
Examination - Tender abdomen
AXR look for dilated stomach, double bubble with distal gas, signs of NEC
If responding to resuscitation - UGI contrast
If not - theatre
At operation
RUQ incision to past midline for neonate
Midline incision for older child
Decisions:
If all SB necrotic and neonate- do not resect, place vac dressing and discuss in MDT and with family in daytime hours
If stable, proceed to ladds procedure +/- anastomosis or stoma if resection
If unstable - Vac dressing +/- clip + drop
Special scenario - incidental malrotation
Determine if symptomatic - history and exam, look for unexplained and repeated vomiting, malnutrition suggesting chronic volvulus - if symptomatic, repair after discussion with the cardiac surgeons
If asymptomatic - define if cardiac disease or non-cardiac disease APSA 2015 systematic review does not support screening asymptomatic cardiac patients
APSA recommendations - conflicting, weak evidence:
Need to assess risk of narrow mesentery and volvulus vs adhesional SBO
APSA review suggests better outcomes if Ladds performed at younger age - Quality adjusted life expectancy for prophylactic Ladd’s is highest at 1 year, declines up to 20 years old
Non-cardiac older child - offer laparoscopic assessment of mesentery +/- Ladds - APSA paper suggests more benefit in younger patients
Non-cardiac neonate - contrast follow through and/or enema to determine location of caecum. If caecum is near DJ flexure, perform laparotomy + Ladds
Cardiac disease patient - wait for correction of cardiac defects - reports of shunt thrombosis and death if Ladds performed first
MDT with cardiac surgeons + cardiologist
Risk of volvulus in one series 2%, risk of adhesive SBO 7-20%
2014 JPS paper (Hill et al) Right atrial isomerism more likely to have narrow mesentery than left
Perform contrast follow through and/or enema to determine location of caecum. If caecum is near DJ flexure - offer laparoscopic assessment of mesentery +/- Ladds
Involve parents in decision making
Index Paper
Journal of Pediatric Surgery 2023 Huerta et al:
Findings: Ladd procedures in newborns with HS were associated with higher complication rates, including surgical site dehiscence, sepsis, infections, venous thrombosis, and prolonged mechanical ventilation compared to those without HS
Conclusion: Relative risks of this procedure as prophylaxis for volvulus and bowel obstruction outweigh the benefits
Page edited by Prof. Ashok Daya Ram MBBS, FRCS, FRCPS, FEBPS, FRCS (Paed Surgery), Consultant Paediatric and Neonatal Surgeon, Norfolk and Norwich University Hospital, Norwich, UK. March 2025
References
Stehr, Wolfgang. "Intestinal Rotational Abnormalities." Pediatric Surgery NaT, American Pediatric Surgical Association, 2022. Pediatric Surgery Library, www.pedsurglibrary.com/apsa/view/Pediatric-Surgery-NaT/829042/all/Intestinal_Rotational_Abnormalities.
Fawley JA, Abdelhafeez AH, Schultz JA, Ertl A, Cassidy LD, Peter SS, Wagner AJ. The risk of midgut volvulus in patients with abdominal wall defects: A multi-institutional study. J Pediatr Surg. 2017 Jan;52(1):26-29. doi: 10.1016/j.jpedsurg.2016.10.014. Epub 2016 Oct 25. PMID: 27847120.
Graziano K, Islam S, Dasgupta R, Lopez ME, Austin M, Chen LE, Goldin A, Downard CD, Renaud E, Abdullah F. Asymptomatic malrotation: Diagnosis and surgical management: An American Pediatric Surgical Association outcomes and evidence based practice committee systematic review. J Pediatr Surg. 2015 Oct;50(10):1783-90. doi: 10.1016/j.jpedsurg.2015.06.019. Epub 2015 Jun 30. PMID: 26205079.
Hill SJ, Heiss KF, Mittal R, Clabby ML, Durham MM, Ricketts R, Wulkan ML. Heterotaxy syndrome and malrotation: does isomerism influence risk and decision to treat. J Pediatr Surg. 2014 Jun;49(6):934-7; discussion 937. doi: 10.1016/j.jpedsurg.2014.01.026. Epub 2014 Jan 31. PMID: 24888838.
Huerta CT, Saberi RA, Lynn R, Ramsey WA, Gilna GP, Parreco JP, Sola JE, Perez EA, Thorson CM. Outcomes After Ladd Procedures for Intestinal Malrotation in Newborns with Heterotaxy Syndrome. J Pediatr Surg. 2023 Jun;58(6):1095-1100. doi: 10.1016/j.jpedsurg.2023.02.013. Epub 2023 Feb 17. PMID: 36941169.