Robotic median arcuate ligament release in a pediatric surgery center

Abstract

Purpose

Median arcuate ligament syndrome is characterized by chronic abdominal pain due to compression and neurofibrosis of the celiac trunk. While it frequently presents in adulthood, adolescents can be affected. The syndrome is often treated with an open median arcuate ligament release. Robotic surgery has grown in popularity for complex cases to improve visualization and post-operative recovery, however there is limited data on the feasibility and benefits of robotic median arcuate ligament release compared to an open procedure, particularly in a pediatric cohort.

Methods

A retrospective review of a single pediatric surgery center’s experience was performed from August 2021 to July 2025, during which time patients underwent open (n = 7) or robotic (n = 10) release of their median arcuate ligament.

Results

There was no difference in operative time or complications between the two groups, however, patients who underwent robotic repair had a median length of stay of one day, significantly shorter than those undergoing open repair, with a median length of stay of four days (p = 0.0128).

Conclusion

Robotic surgery for median arcuate ligament syndrome can be done by robotic-trained pediatric surgeons, which may offer shorter hospital stays without significant operative delays or increased risk of complications.

Supplementary Information

The online version contains supplementary material available at https://doi.org/10.1007/s00383-026-06609-x.

Median arcuate ligament syndrome (MALS) is a rare neurovascular disease characterized by chronic abdominal pain. It is thought to be secondary to a combination of celiac artery compression by the median arcuate ligament (MAL) and neurofibrosis with inflammatory changes in the celiac artery ganglia, however the exact etiology is not fully understood [1, 2]. Celiac plexus blocks have been shown to temporarily reduce symptoms in patients diagnosed with MALS suggesting a neurogenic component to the pathophysiology [3, 4]. Surgical decompression of the celiac artery with MAL release has also been shown to improve symptoms. It is hypothesized that division of the MAL additionally disrupts the celiac ganglion, so the improvement in symptoms may be due to the combined relief of celiac artery compression and division of abnormal nerve bundles.

MALS is often diagnosed in adults, with a female preponderance most often between the ages of 40 to 60 years, however the disease can be diagnosed in pediatric populations, typically during adolescence. The mainstay of treatment for MALS has been surgical excision of the median arcuate ligament through an open laparotomy, however, there has been an increase in utility of minimally invasive approaches for surgical management of MALS with both laparoscopic and robotic approaches gaining favor [5, 6]. One study found better symptom relief in adults with robotic MAL release over laparoscopic MAL release [7]. Laparoscopic MAL release has been described in pediatric patients [8, 9]. Unfortunately, there is limited evidence on the feasibility and benefits of robotic surgery for management of MALS in an adolescent population. There is no study currently comparing open and minimally invasive MAL release in pediatric patients. One study showed safety of robotic median arcuate ligament release in a 12 and a 15 year old, while another study demonstrated safety in 12 pediatric patients with histopathologic descriptions of neurofibrosis, similar to what is seen in adults [10, 11].

This is the first study in a pediatric population comparing open and robotic MAL release. This study aims to further describe the technique of robotic MAL release and to compare outcomes between open and robotic MAL release in a pediatric population.

Methods

Study design

A retrospective review was performed on patients undergoing surgical treatment of MALS from August 2021 to July 2025. Patients were included in the study if the surgery was performed by a pediatric surgeon and underwent MAL release.

Patient work-up

Any patient referred to pediatric surgery for evaluation of MALS undergoes a duplex ultrasound looking for elevation in celiac artery velocities. We additionally get a CT angiogram on the majority of patients, looking for celiac trunk compression or a J-hook configuration on the sagittal image. All patients are offered an interventional radiology referral for celiac plexus blockade, and it is a part of our diagnostic work-up for any patient that has ambiguity in their imaging or presentation prior to operative intervention.

Open repair

Prior to induction of anesthesia, all patients with open repairs were given an epidural for postoperative pain control. They were then placed supine and the case proceeded under general anesthesia with an orogastric tube in place. A midline laparotomy was performed for all patients undergoing open repair. Histologic specimens were not collected in all patients during our study period, but has become standard technique to evaluate for neurofibrosis and inflammation in both open and robotic repair [10]. Post-operative care included an acute pain anesthesia consultation with multimodal pain management including the preoperatively placed epidural and patient-controlled analgesia (PCA).

Robotic repair

As with open repairs, patients were positioned supine under general anesthesia with an orogastric tube in place. Patients received an intra-operative TAP block with local anesthetic under direct visualization. Over the course of the study robotic trocar positioning was adjusted to optimize our technique, with final port positioning shown in Fig. 1. Post-operative care included multimodal pain management by the surgical team with acetaminophen, Toradol, and oral narcotics.

Fig. 1.

Port sites for robotic median arcuate ligament release. Access with a veress (v) needle is followed by optiview entry in the left upper abdomen where our 8 mm port for arm three will go. We use four 8 mm ports in a supraumbilical transverse plane and a 5 mm assist port for suctioning and retraction. In smaller patients, the left-most port can be sacrificed and the assist port [A] used for more leftward gastric retraction. A A 5 mm port with a snake retractor (S) or B a Nathanson retractor (N) are used for liver elevation

Data collection

Data collected for evaluation included demographic data, preoperative patient characteristics and imaging results, operative times, and postoperative outcomes. Demographic data included sex, age, and BMI. Pre-operative patient characteristics included patient symptoms and comorbidities, celiac artery velocity on duplex ultrasound, the presence of celiac artery compression on CT angiography, and whether the patient experienced relief from a celiac plexus block prior to the operation.

Primary outcomes were total operative time and length of hospital stay. Operative time was defined as time from skin incision to when dressings were placed. Secondary outcomes included robotic docking time when available, complications, symptom improvement at 30 days postoperatively, and if the patient developed recurrent symptoms.

Statistical analysis

Data was analyzed using IBM SPSS Statistics for Windows, version 31 (IBM Corp., Armonk, N.Y., USA). Categorical variables were analyzed using the Fisher’s Exact test and continuous variables were analyzed using the Mann-Whitney U test of significance, with P < 0.05 denoting significance.

Results

Patient selection

During our study period, 16 patients for a total of 18 surgeries for MALS we identified. Of these, only one was performed laparoscopically and therefore was too underpowered to include in our analysis. Two patients had open MAL release following recurrence of their symptoms after robotic release, and both the robotic and open surgeries were included as separate data points. There were seven open MAL release operations performed and 10 robotic MAL release operations performed that were included for analysis.

Patient demographics and characteristics

There was no statistically significant difference in patient demographics, preoperative symptoms, or associated comorbidities between the open and robotic MAL release groups (Table 1). All patients who underwent celiac plexus block pre-operatively had relief of symptoms for a period of time following the block. Patients undergoing open MAL release had similar celiac artery velocities compared to those undergoing robotic MAL release at 264 cm/s compared to 258 cm/s, respectively. Both groups had similar rates of celiac artery compression on CT angiography.

Table 1.

Patient demographics

Patient demographic	Open repair (n = 7)	Robotic repair (n = 10)	p valuea
Female sex at birthb	6 (85.7)	7 (70)	0.603
Age (years)c	16.3 (16.1–19.2)	15.9 (15.0–17.0)	0.558
BMIc	21.7 (18.6–28.0)	20.6 (19.3–25.5)	0.306
Pre-op Celiac Artery Velocity (cm/s)	264 (197–386)	258 (205–330)	0.724
Compression on CTA	6 (85.7)	9 (90)	1.000
Relief from Celiac Plexus Block	6/6 (100)	7/7 (100)	–
Symptoms
Abdominal pain	7 (100)	10 (100)	–
Post prandial pain	6 (85.7)	8 (80)	1.000
Nausea	5 (71.4)	7 (70)	1.000
Vomiting	5 (71.4)	4 (40)	0.335
Weight Loss	3 (42.9)	6 (60)	0.637
Comorbidities
Gastroparesis	2 (28.6)	0 (0)	0.154
IBS	1 (14.3)	1 (10)	1.000
GERD	2 (28.6)	4 (40)	1.000
Depression	3 (42.9)	2 (20)	0.593
SMA Syndrome	4 (57.1)	1 (10)	0.101
POTS	2 (28.6)	1 (10)	0.537
Colonic dysmotility	4 (57.1)	4 (40)	0.637

BMI body mass index, CTA CT angiography, IBS irritable bowel syndrome, GERD gastroesophageal reflux disease, SMA superior mesenteric artery, POTS postural orthostatic tachycardia syndrome

^aP-value < 0.05 denotes significance (bolded)

^bValues are represented as n (%)

^cValues are represented as median (IQR)

Outcomes

Total operative time was not significantly different between open and robotic MAL release, with median open operative time of 127 min compared to 164 min for those undergoing robotic repair (P = 0.1113), as shown in Table 2. The median duration of robotic docking time was 102 min. Patients undergoing robotic MAL release had a median length of stay of 1 day while patients undergoing open repair stayed in the hospital a median of 4 days (P = 0.0128). Not included in our statistical analysis, the patient who underwent laparoscopic repair had an operative time of 147 min and a length of stay of 2 days. There was one complication in our cohort; the patient had bleeding from their celiac artery during robotic release. They did not require any blood transfusions but did require emergent conversion to laparotomy to control the bleed. There was no difference in the frequency of recurrent symptoms (p = 0.485), however, two patients in the robotic group did have recurrent symptoms and went on to have an open repair.

Table 2.

Patient outcomes for open versus robotic median arcuate ligament release

Outcomes	Open repair (n = 7)	Robotic repair (n = 10)	p valuea
Total operative time (min)b	127 (100–127)	164 (123.5–213)	0.1113
Robotic docked time (min)b	–	102 (71.5–141.25)	–
Length of stay (days)b	4 (2–4)	1 (1–1.75)	0.0128
Complicationc	0 (0)	1 (10)	1.000
Improvement in symptoms at 30 daysc	6 (85.7)	9 (90)	1.000
Recurrent symptomsc	0 (0)	2 (20)	0.485

Patients undergoing robotic MAL release had significantly shorter hospital lengths of stay

^aP value < 0.05 denotes significance (bolded)

^bValues are represented as median (IQR)

^cValues are represented as n (%)

Discussion

This is the first study in a pediatric population to demonstrate non-inferiority of robotic MAL release compared to open laparotomy for symptom relief and safety, while demonstrating a significant reduction in hospital length of stay when utilizing the minimally invasive technique. We found a three-day reduction hospital length of stay with robotic MAL compared to open release. Patients were considered safe for discharge once ambulating, tolerating an oral diet with pain control on oral analgesics, and with normal hemodynamics. However, there is not a standardized discharge criteria checklist at our institution, so prospective analysis of length of stay with standardized discharge criteria across groups would strengthen future studies. While not directly studied in our cohort, adult studies have shown robotic MAL release is associated with decreased postsurgical pain and decreased rates of ileus or delayed gastric emptying which can contribute to shorter hospital stays [12, 13].

The decision to proceed with an open or robotic approach for MAL release was patient-centered, with patients undergoing primary release being offered both open and robotic approaches during the study period. Some patients opted for a primary open MAL release due to the robotic technique being a newer technique. Patients who had recurrent symptoms, regardless of technique, were recommended an open approach for their second operation.

One concern with the adoption of minimally invasive techniques, particularly robotic techniques, is longer operative times. We found no significant difference in operative times between open and robotic procedures, although there was a trend toward longer total operative times with median duration 37 min longer for robotic cases than open cases. However, as shown in Supplemental Fig. 1, there was a trend in improved operative times for our robotic operations as our volume of experience increased. One way we improved operative times on the robot was with port placement optimization, with our current port placement shown in Fig. 1. Either a snake or Nathanson liver retractor can be used for foregut exposure, and we find an assist port allows for both suctioning and caudal retraction during the case. We believe that with ongoing experience the operative times for the two techniques will likely become more similar.

One benefit we find with robotic surgery for MAL release is the improved visualization of foregut anatomy (Fig. 2) and visualization of the neuromuscular sheath that needs to be excised (Fig. 3). We agree with DeCicco et al., who described excision of the neurofibrosis in pediatric patients as a critical step in treatment of MALS [10]. Neurofibrosis and inflammation has been found in the excised specimens. Figure 4 shows some of our techniques for division of the median arcuate ligament and excision of the neuromuscular fibrosis that surrounds the celiac trunk in these patients.

Fig. 2.

Key dissection anatomy with the celiac trunk marked with a white asterix. Outlined is the celiac trunk branching into the common hepatic artery right anteriorly and the left gastric artery transversely. The splenic artery is rarely seen during dissection with a more posterior takeoff at the celiac trifurcation. Variant anatomy can be seen in some patients (not pictured) with accessory phrenic arteries coming off the celiac trunk. There remains a thin layer of hypertrophied nerves overlying these vessels, which will be removed after fully delineating the anatomy. The fenestrated bipolar and Maryland bipolar forceps are holding the thickened median arcuate ligament

Fig. 3.

To aid in dissection directly along the artery, we use the Maryland forceps to act as both a dissection tool and for electrocautery. Dissection in this figure is being performed along the left gastric artery coming off the celiac trunk. A The bipolar forceps is used to elevate the perivascular nerves and muscle fibers while the Maryland forceps bluntly dissects to create a tunnel. B With a safe distance between the vessel and the overlying nerves, C electrocautery can be used to ensure hemostasis. D Adequately cauterized tissue will easily divide when pulled apart using the bipolar forceps and Maryland forceps

Fig. 4.

A The hook electrocautery can be a useful instrument when dividing the hypertrophied muscles and nerves of the median arcuate ligament overlying the aorta and proximal celiac trunk. We opt to only use this when there is adequate space below the heel of the hook, as division of the neuromuscular bundle can rapidly relieve vascular compression, resulting in an elevation of the vessel toward the heated hook and risking vascular injury. B Once the aorta has been cleared and the anatomy delineated, we return to the celiac trunk to dissect off the final layer of hypertrophied nerves and muscles overlying these vessels. The posterior packet of nerves and muscles are elevated and excised to improve circumferential release of the neuromuscular vascular compression. We have found that excision, rather than dissection provides more sustainable symptom relief. The posterior dissection is most easily done after the anterior dissection is completed, so is saved as the final step in our median arcuate ligament release

This study is limited in being retrospective in nature and is a single center experience with limited power to identify differences in symptom recurrence or complications. We had one patient that was converted to an open release due to bleeding from the celiac trunk. The patient did not require any blood transfusions and had a five-day hospital length of stay. Two patients in the robotic group had recurrent symptoms and underwent open releases following symptom recurrence. With a larger patient cohort, it is possible that we would find a difference in symptom recurrence between robotic and open procedures, however, we feel that the potential to have symptom resolution with a significant reduction in hospital length of stay warrants a first-line approach to be with minimally invasive techniques when feasible.

The subgroup of patients who underwent a laparoscopic MAL release at our institution was limited to a single patient and was too small of a cohort to include in our statistical analysis. A future multi-institutional study comparing robotic and laparoscopic MAL release across institutions would improve our understanding of the safety and feasibility of different minimally invasive techniques for MAL release in pediatric patients.

We did not assess long-term outcomes in this retrospective review. Asymptomatic patients did not return to clinic after their first one-month follow-up, so we may be missing patients who go to other providers for recurrent symptoms. There are no studies looking at long-term MAL release outcomes in adolescents. Prospective studies comparing long-term outcomes will be critical for confirming efficacy of both open and robotic MAL release in this age group.

In conclusion, this study highlights the potential benefit of robotic surgery for the treatment of MALS in pediatric patients. While multi-institutional studies are needed to better elucidate the risk of recurrent symptoms and complications associated with these techniques, we have shown that robotic techniques can be used for the initial surgical management of MALS with reductions in hospital lengths of stay and without increased morbidity.

Supplementary Information

Below is the link to the electronic supplementary material.

Supplementary Material 1 ^{(17.5KB, docx)}

Author contributions

S.N. contributed in the Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Project administration, Resources, Validation, Visualization, Writing – original draft, and Writing – review and editing. A.G. contributed in the Conceptualization, Methodology, Project administration, Resources, Supervision, Validation, Visualization, and Writing – review and editing. Study conception and design: Stephen Niemiec, Alejandro Garcia. Acquisition of data: Stephen Niemiec. Analysis and interpretation of data: Stephen Niemiec. Drafting of manuscript: Stephen Niemiec, Alejandro Garcia. Critical revision of manuscript: Stephen Niemiec, Alejandro Garcia.

Funding

The authors did not receive support from any organization for the submitted work.

Data availability

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Declarations

Conflict of interest

The authors have no financial or proprietary interests in any material discussed in this article.

Declaration of AI-assisted technologies in the Manuscript Preparation Process

During the preparation of this work the author(s) used ChatGPT in the design of Fig. 1. After using this tool/service, the author(s) reviewed and edited the content as needed and take(s) full responsibility for the content of the published article.