Superior mesenteric artery syndrome is obstruction of the third portion of the duodenum by compression between the abdominal aorta and superior mesenteric artery. Pediatric orthopedists are familiar with this entity, as the association between superior mesenteric artery syndrome and spinal fusion or body casting has been well established. However, patients with spinal deformities usually experience superior mesenteric artery syndrome after orthopedic intervention, with rates after corrective spinal surgery reported between 0.5% and 2.4%.
Symptoms of superior mesenteric artery syndrome typically include nausea, bilious emesis, abdominal pain, early satiety, and anorexia. Initial treatment focuses on gastric decompression and maintaining euvolemia and electrolyte balance. The patient should receive enteral nutrition via nasojejunal tube or parenteral nutrition to allow for weight gain and subsequent resolution of the obstruction.
The superior mesenteric artery takes off from the duodenum at an angle of 45° to 60° in normal individuals. The third portion of the duodenum is suspended between these vessels by the ligament of Treitz. Any variation in this relationship that decreases the arteriomesenteric angle may induce obstruction. Specifically, lumbar hyperextension or hyperlordosis can traction the mesentery and vessels. Only 2 cases of superior mesenteric artery syndrome in patients with sagittal plane spinal deformity have been described in the literature. In patients with concomitant superior mesenteric artery syndrome and spinal deformity, correction of the deformity may help alleviate the obstruction and result in faster recovery. The contribution of spinal column deformity to the arteriomesenteric angle should not be overlooked.
Pediatric orthopedists are familiar with superior mesenteric artery syndrome as it is a well-known sequela of scoliosis surgery. This article presents a case of a rare non-iatrogenic case of superior mesenteric artery syndrome caused by multiplanar spinal deformity. Ultimately, the patient required corrective spinal surgery to alleviate his superior mesenteric artery syndrome.
A 14-year-old boy with a history of pervasive developmental disorder (autism spectrum) and scoliosis presented with abdominal pain and bilious emesis. He weighed 40.5 kg and was 162.5 cm tall (body mass index [BMI] 15.2). The patient was diagnosed with superior mesenteric artery syndrome after an upper gastrointestinal contrast study (Figure 1). He was treated with gastric decompression and nutritional supplementation via a nasojejunal feeding tube. After appropriate weight gain with enteral nutrition, he tolerated an oral diet and was discharged home.
Figure 1: Upper GI study demonstrating proximal duodenal dilation and occlusion of the third portion of the duodenum. Note the absence of contrast in the fourth portion of the duodenum.
The patient was diagnosed with scoliosis at 12 years. He had a 1- to 2-month trial of thoracolumbosacral orthosis use but he did not tolerate the brace and it was discontinued. Radiographs at the time of presentation demonstrated a 70° thoracolumbar region curvature and thoracic hypokyphosis measuring 2°(Figure 2).
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Figure 2: PA (A) and lateral (B) radiographs of the spine prior to intervention demonstrate a 70° thoracolumbar curve with thoracic hypokyphosis.
Despite nutritional supplementation, the patient experienced recurrent superior mesenteric artery syndrome 5 months after the first episode. During hospitalization, he underwent gastrostomy tube placement to provide better gastric decompression. At the time of the gastrostomy tube placement, it was noted that the lumbar hyperlordosis was prominent at the precise location of the superior mesenteric artery overlying the duodenum. The superior mesenteric artery syndrome was recurrent despite treatment with gastric decompression, enteral feedings distal to the obstruction, and appropriate weight gain. Because these usual measures failed, it was determined that the patient would continue to experience superior mesenteric artery syndrome until the spinal deformity was corrected.
The patient underwent correction of multiplanar spinal deformity with posterior spinal fusion from T3 to L3 with segmental instrumentation (M10 Titanium; Medtronic, Minneapolis, Minnesota). He weighed 43.4 kg and was 173 cm tall at the time of surgery (BMI 14.5). A midline posterior approach was used. The patient had an uncomplicated postoperative course and was discharged on postoperative day 11. At initial follow-up, the patients thoracolumbar curve measured 35° with 24°of thoracic kyphosis (Figure 3).
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Figure 3: PA (A) and lateral (B) postoperative radiographs after surgical correction demonstrate improved sagittal and coronal profiles.
At 1-month follow-up, the patient's superior mesenteric artery syndrome had begun to improve. An upper gastrointestinal study revealed less dilation of the proximal duodenum and passage of contrast into the fourth portion of the duodenum. At 3-month follow-up, the superior mesenteric artery syndrome had fully resolved. The patient continued feeding through a gastrostomy tube due to an oral aversion that developed early in the course of his superior mesenteric artery syndrome. At most recent follow-up, the patient weighed 56.1 kg and was 171.5 cm tall (BMI 19.1).
Superior mesenteric artery syndrome is obstruction of the third portion of the duodenum by compression between the abdominal aorta and superior mesenteric artery. Patients typically present after rapid weight loss or orthopedic intervention such as casting or instrumented spinal fusion.1-10 Pediatric patients commonly have comorbidities including cerebral palsy or other neurologic injury.11 Superior mesenteric artery syndrome is also seen in adults after trauma12 or with anorexia,13 and it is thought to be secondary to sudden, acute weight loss.
The superior mesenteric artery takes off from the duodenum at an angle of 45° to 60° in normal individuals.14 The third portion of the duodenum is suspended between these vessels by the ligament of Treitz. Any variation in this relationship that decreases the arteriomesenteric angle may induce obstruction.15,16 Specifically, lumbar hyperextension or hyperlordosis can traction the mesentery and vessels.17 This may be caused by spinal deformity, prolonged recumbency, or orthopedic casting. Loss of mesenteric fat will also decrease the arteriomesenteric angle.
Symptoms of superior mesenteric artery syndrome typically include nausea, bilious emesis, abdominal pain, early satiety, and anorexia.11 Initial treatment focuses on gastric decompression and maintaining euvolemia and electrolyte balance. Placing the patient in the lateral decubitus position can open the arteriomesenteric angle. Any external apparatus should be removed promptly. The patient should receive enteral nutrition via nasojejunal tube or parenteral nutrition to allow for weight gain and subsequent resolution of the obstruction.11 Although operative treatment was common in early series,2,9,10 nonoperative management is the mainstay of current treatment.3,4,11
Spinal deformity and superior mesenteric artery syndrome are commonly associated. However, these patients do not experience duodenal obstruction until after corrective surgery. The incidence of superior mesenteric artery syndrome after scoliosis correction is reported to be 0.5% to 2.4%.1,4,5,7 Rapid growth prior to diagnosis or treatment of scoliosis has been suggested as a contributing factor. The acute increase in vertebral column length with corrective surgery may also contribute by placing additional traction on the superior mesenteric artery. Postoperative weight loss, recumbency, and more extensive procedures have also been implicated in the development of superior mesenteric artery syndrome after corrective spinal surgery.8 The average onset is 12 days after surgery, but may be delayed.4 Authors have suggested that preoperative weight gain7 or perioperative dietary supplementation6 may reduce the risk of superior mesenteric artery syndrome. Much attention has been devoted to determining the risk factors associated with postoperative superior mesenteric artery syndrome. A thin, asthenic body habitus is one commonly cited risk factor.2 Shah et al6 suggested that patients below the fifth percentile of weight for height are at increased risk. Altiok et al1 and Smith et al18 believed BMI to be the best indicator of risk. Recent studies have confirmed that the arteriomesenteric angle correlates with BMI.19
Lipton et al20 previously reported correction of spinal deformity as primary treatment of a subset of patients in their series with primary superior mesenteric artery syndrome. The patients had cerebral palsy and purely sagittal plane deformities. Our patients lumbar hyperlordosis included multiplanar deformity. Our experience suggests that the contribution of spinal column deformity to the arteriomesenteric angle should not be forgotten. In patients with concomitant superior mesenteric artery syndrome and spinal deformity, correction of the deformity may help alleviate the obstruction and result in faster recovery.
- Altiok H, Lubicky JP, DeWald CJ, Herman JE. The superior mesenteric artery syndrome in patients with spinal deformity. Spine (Phila Pa 1976). 2005; 30(19):2164-2170.
- Bunch W, Delaney J. Scoliosis and acute vascular compression of the duodenum. Surgery. 1970; 67(6):901-906.
- Crowther MA, Webb PJ, Eyre-Brook IA. Superior mesenteric artery syndrome following surgery for scoliosis. Spine (Phila Pa 1976). 2002; 27(24):528-533.
- Hutchinson DT, Bassett GS. Superior mesenteric artery syndrome in pediatric orthopedic patients. Clin Orthop Relat Res. 1990; (250):250-257.
- Munns SW, Morrissy RT, Golladay ES, McKenzie CN. Hyperalimentation for superior mesenteric-artery (cast) syndrome following correction of spinal deformity. J Bone Joint Surg Am. 1984; 66(8):1175-1177.
- Shah MA, Albright MB, Vogt MT, Moreland MS. Superior mesenteric artery syndrome in scoliosis surgery: weight percentile for height as an indicator of risk. J Pediatr Orthop. 2003; 23(5):665-668.
- Tsirikos AI, Jeans LA. Superior mesenteric artery syndrome in children and adolescents with spine deformities undergoing corrective surgery. J Spinal Disord Tech. 2005; 18(3):263-271.
- Braun SV, Hedden DM, Howard AW. Superior mesenteric artery syndrome following spinal deformity correction. J Bone Joint Surg Am. 2006; 88(10):2252-2257.
- Dorph MH. The cast syndrome; review of the literature and report of a case. N Engl J Med. 1950; 243(12):440-442.
- Evarts CM, Winter RB, Hall JE. Vascular compression of the duodenum associated with the treatment of scoliosis. Review of the literature and report of eighteen cases. J Bone Joint Surg Am. 1971; 53(3):431-444.
- Biank V, Werlin S. Superior mesenteric artery syndrome in children: a 20-year experience. J Pediatr Gastroenterol Nutr. 2006; 42(5):522-525.
- Smith BM, Zyromski NJ, Purtill MA. Superior mesenteric artery syndrome: an underrecognized entity in the trauma population. J Trauma. 2008; 64(3):827-830.
- Pentlow BD, Dent RG. Acute vascular compression of the duodenum in anorexia nervosa. Br J Surg. 1981; 68(9):665-666.
- Wayne E, Miller RE, Eiseman B. Duodenal obstruction by the superior mesenteric artery in bedridden combat casualties. Ann Surg. 1971; 174(3):339-345.
- Almgren B, Juhl M. Superior mesenteric artery syndrome complicating treatment with balanced traction. A case report. Acta Orthop Scand. 1977; 48(1):25-28.
- Walker C, Kahanovitz N. Recurrent superior mesenteric artery syndrome complicating staged reconstructive spinal surgery: alternative methods of conservative treatment. J Pediatr Orthop. 1983; 3(1):77-80.
- Leigh TF. Acute gastric dilatation. J Am Med Assoc. 1960; (172):1376-1381.
- Smith BG, Hakim-Zargar M, Thomson JD. Low body mass index: a risk factor for superior mesenteric artery syndrome in adolescents undergoing spinal fusion for scoliosis. J Spinal Disord Tech. 2009; 22(2):144-148.
- Ozkurt H, Cenker MM, Bas N, Erturk SM, Basak M. Measurement of the distance and angle between the aorta and superior mesenteric artery: normal values in different BMI categories. Surg Radiol Anat. 2007; 29(7):595-599.
- Lipton GE, Letonoff EJ, Dabney KW, Miller F, McCarthy HC. Correction of sagittal plane spinal deformities with unit rod instrumentation in children with cerebral palsy. J Bone Joint Surg Am. 2003; 85(12):2349-2357.
Drs Marecek and Sarwark are from the Department of Orthopedic Surgery, Northwestern University, and Drs Barsness and Sarwark are from The Childrens Memorial Hospital, Chicago, Illinois.
Drs Marecek, Barsness, and Sarwark have no relevant financial relationships to disclose.
Correspondence should be addressed to: Geoffrey S. Marecek, MD, Department of Orthopedic Surgery, Northwestern University, 676 N Saint Clair St, Ste 1350, Chicago, IL 60611 (firstname.lastname@example.org ).