Simultaneous Management of May-Thurner Syndrome and Spigelian Hernia: A Case Report

Introduction

May-Thurner syndrome is characterized by compression of the left common iliac vein (LCIV) by the right common iliac artery (RCIA) against the lumbar vertebrae [1]. This condition, which may or may not be associated with iliofemoral deep vein thrombosis (DVT), was first described in a seminal 1957 report by May and Thurner. In their study of 430 cadavers, LCIV compression by the RCIA was observed in 22% of cases. The authors proposed that repetitive arterial pulsations of the RCIA against the LCIV could promote formation of an intimal “spur,” contributing to venous obstruction [1–3].

Although some investigators regard May-Thurner syndrome as an asymptomatic vascular anomaly, others associate it with chronic venous insufficiency, venous obstruction with collateral formation, or DVT [2]. Diagnostic imaging, particularly computed tomography (CT) or magnetic resonance venography, is essential for confirmation. Treatment typically includes mechanical thrombolysis, endovascular stenting of the left iliac vein, and anticoagulation therapy for at least 6 months [4].

Spigelian hernia is a rare abdominal wall defect that occurs at the junction of the lateral border of the rectus sheath and the arcuate line. It involves a fascial defect in the posterior sheath of the rectus abdominis muscle [5]. Elevated intra-abdominal pressure and trauma have been proposed as potential contributing factors [5]. The hernia sac lies beneath an intact external oblique aponeurosis, which often obscures clinical detection because a prominent external bulge is typically absent [6].

Although Spigelian hernia constitutes approximately 0.1% of all abdominal hernias, its clinical importance lies in the high risk of strangulation [7]. Diagnosis frequently requires imaging studies because clinical evaluation alone is usually insufficient. Management is most commonly achieved through minimally invasive repair with mesh reinforcement of the abdominal wall [8].

May-Thurner syndrome, involving extrinsic compression of the adjacent vein, is associated with a risk of vascular injury and increased collagen deposition within the venous wall. Therefore, it remains unclear whether Spigelian hernia and May-Thurner syndrome share a common pathophysiologic mechanism related to collagen metabolism [9]. Here, we describe concomitant May-Thurner syndrome and Spigelian hernia in an older woman who exhibited left leg swelling and intermittent right lower abdominal pain due to compression and thrombosis of the LCIV by an overriding RCIA, along with a right-sided Spigelian hernia. This report offers a reference for clinicians who encounter similar presentations.

Case Report

A 63-year-old woman presented with symptomatic left leg DVT secondary to May-Thurner syndrome and a concomitant right-sided Spigelian hernia. She initially developed left lower extremity edema, for which percutaneous intervention was performed to treat venous obstruction. During the same admission, she experienced bowel obstruction and right lower quadrant abdominal pain, leading to a diagnosis of incarcerated Spigelian hernia. Subsequently, she underwent laparoscopic repair of the Spigelian hernia. Details of the vascular assessment and intervention are as follows. Doppler ultrasound confirmed a non-occlusive thrombus in the LCIV extending throughout the venous system of the left leg. Contrast-enhanced CT revealed compression of the LCIV between the RCIA and the L5 vertebra, consistent with May-Thurner syndrome. Additionally, imaging demonstrated left lower extremity DVT (Figure 1A, 1B).

Anticoagulation therapy was initiated with a continuous high-intensity heparin infusion. The interventional radiology team performed endovascular mechanical thrombectomy, followed by stent placement in the left iliac vein (Figure 2A, 2B).

Percutaneous access to the popliteal vein was obtained under ultrasound guidance using the Seldinger technique. A 5-French sheath was introduced over a 0.035-inch Benson wire. A Glidewire was advanced through the thrombosed left external iliac vein and LCIV into the inferior vena cava (IVC). An Amplatz wire was subsequently inserted and advanced to the left internal jugular vein, after which the introducer sheath was upsized to a 13-French Inari vascular sheath.

Initial balloon maceration was performed using a 10×80-mm Mustang balloon. The balloon was then exchanged for a 13-French clot retriever; 4 passes were performed from the level of the inferior vena cava to the popliteal vein, retrieving a substantial thrombus burden. Intravascular ultrasound was used to delineate venous anatomy, after which a 16×120-mm Medtronic Abre stent was deployed in the LCIV. This self-expanding stent was post-dilated with a 14×40-mm Atlas Gold balloon. Intraprocedural venography confirmed successful re-establishment of venous flow. The sheath and wires were removed; hemostasis was achieved with direct pressure and application of a pressure dressing. The patient was prescribed apixaban for 6 months.

After LCIV stenting, a nasogastric tube was placed due to large-volume emesis. The patient reported right lower quadrant abdominal discomfort with obstructive symptoms, and physical examination revealed a firm bulge in the same region. The general surgery team was consulted for evaluation of a small bowel obstruction associated with a right-sided Spigelian hernia identified on the initial abdominal CT scan (Figure 3A, 3B). The patient had no history of abdominal surgery or hernia. The hernia was manually reduced, with restoration of bowel lumen patency. Abnormal laboratory findings resolved, and the patient subsequently underwent a scheduled intraperitoneal onlay mesh repair of the Spigelian hernia (Figure 4) during her hospital stay.

During the procedure, the abdomen was accessed using a Veress needle, and 2 additional 5-mm ports were placed in the left upper mid-abdomen. Adhesions were lysed using laparoscopic EndoShear scissors. Small bowel loops were reduced from the hernia sac without injury, and the sac was excised using a laparoscopic LigaSure dissector. The fascial edges of the hernia defect were approximated with 3-0 V-Loc sutures. ST Dual Phasix mesh (Bard, Inc., Warwick, RI, USA) was positioned to cover the defect with a 5-cm overlap and secured with AbsorbaTack (Medtronic, Minneapolis, MN, USA). The 10-mm laparoscopic port site was closed at the fascial level with 0-PDS sutures, and the skin was approximated with 4-0 Monocryl sutures (Ethicon, Raritan, NJ, USA).

Two years later, the patient presented with symptomatic right lower extremity DVT. Imaging revealed that the previously placed stent extended across the right common iliac vein, with retrograde thrombus propagation to the popliteal vein. Catheter-directed thrombolysis was performed, resulting in improved flow after 2 days, although mild residual eccentric thrombus persisted within the right common iliac and external iliac veins. Aspiration thrombectomy was subsequently performed using a Penumbra CAT 8 device, which successfully removed the organized thrombus. A decision was made not to place a stent in the right common iliac vein, given that satisfactory blood flow had been restored after thrombectomy. This approach was further supported by the finding that IVC caliber was insufficient to accommodate additional parallel stents, although this option may be reconsidered in the future. Anticoagulation therapy was restarted, and lifelong anticoagulation was recommended.

After treatment, the patient was discharged in good general condition and monitored for 4 years by her primary care physician and the general surgery team. During follow-up, she remained asymptomatic, without recurrence of Spigelian hernia on CT imaging. She also did not develop any umbilical, femoral, or incisional hernias and remained fully adherent to her anticoagulation regimen.

Discussion

This case report highlights the co-occurrence of Spigelian hernia and May-Thurner syndrome. The patient presented with a painful, swollen left lower extremity and symptoms of intestinal obstruction. Doppler ultrasound confirmed a non-occlusive thrombus in the LCIV, whereas contrast-enhanced CT revealed compression of the LCIV between the RCIA and the vertebral column. CT findings also indicated a right-sided obstructed Spigelian hernia. Both conditions were successfully managed, and the patient demonstrated excellent clinical outcomes during 4 years of follow-up.

May-Thurner syndrome, also referred to as Cockett syndrome or iliac vein compression syndrome, is characterized by compression of the LCIV by the RCIA, leading to impaired venous return and a low-flow state that can cause LCIV thrombosis. Kibbe et al retrospectively reviewed CT scans of 50 patients who presented to the emergency department for nonvascular symptoms; they reported that LCIV compression may represent a normal anatomic variant, rather than a pathological condition [1,2]. May-Thurner syndrome may result in chronic venous insufficiency, DVT, or, in rare cases, pulmonary embolism [2,3]. Clinical presentation varies widely, ranging from asymptomatic findings to severe venous thrombosis and leg swelling. Individuals with the anatomic variant may remain asymptomatic until later in life, when thrombotic complications develop [2,10].

May-Thurner syndrome can occasionally occur on the right side in the presence of a left-sided IVC [11]. Diagnosis typically relies on clinical suspicion, particularly in younger patients presenting with left-sided lower extremity DVT in the absence of predisposing factors. Early recognition is essential to prevent complications. May-Thurner syndrome constitutes approximately 2% to 5% of all DVT cases [4] and is conventionally diagnosed via CT or venography. Treatment generally involves a combination of endovascular intervention and anticoagulation therapy. Ouriel et al analyzed 2541 patients with lower extremity DVT and found that proximal DVTs were 2.5 times more likely to occur on the left side, whereas distal DVTs were equally distributed between limbs, suggesting an association between left-sided proximal DVT and the May-Thurner syndrome anatomic variant [12]. May-Thurner syndrome is frequently underdiagnosed; a prevalence of 76% was reported among patients with left-sided DVT [13,14].

Imaging modalities such as venography, duplex ultrasound, CT venography, and magnetic resonance venography provide greater than 95% sensitivity and specificity for diagnosing thrombosis associated with May-Thurner syndrome [3,4]. CT and magnetic resonance imaging may identify coexisting conditions [15], such as Spigelian hernia, which was incidentally detected in the present case.

Our patient was successfully treated with endovascular mechanical thrombectomy and stenting, which relieved venous compression. This approach has shown efficacy in restoring venous outflow, alleviating symptoms, and preventing DVT recurrence [16–18]. Although the ATTEST trial demonstrated that thrombolysis is more effective than systemic anticoagulation, patients with left iliac vein thrombosis associated with May-Thurner syndrome often require a combination of mechanical thrombectomy, thrombolysis, stenting, and lifelong anticoagulation rather than thrombolysis alone [19]. After treatment of the DVT, the patient was referred to the general surgery department for evaluation of the Spigelian hernia, which was associated with progressive abdominal pain and vomiting.

Spigelian hernia is a rare abdominal wall hernia, representing less than 2% of all hernias. Diagnosis is often challenging because a visible cutaneous bulge is frequently absent. Patients typically present with nonspecific abdominal symptoms, such as pain, swelling, or bowel obstruction [5]. The hernia occurs at the junction of the semilunar and arcuate lines due to a fascial defect, with the hernia sac partially contained beneath an intact external oblique aponeurosis [6,20].

Ultrasound and CT are commonly used to confirm the diagnosis and exclude alternative conditions (eg, ventral or inguinal hernias). Ultrasound imaging is particularly effective for visualization of hernial structures [5,15]. Examination along the semilunar line with the patient in the standing position, combined with provocative maneuvers such as the Valsalva maneuver, transducer compression, or coughing, may aid assessment of hernia reducibility [20].

Given the risk of complications, including bowel incarceration or strangulation, prompt surgical intervention is recommended once the diagnosis is established [5]. Our patient underwent semi-urgent laparoscopic repair for symptomatic Spigelian hernia. Minimally invasive surgery provides excellent visualization and durable repair; mesh placement substantially lowers recurrence rates. The postoperative course was rapid and uneventful after laparoscopic mesh repair, consistent with published literature [7–9,21].

In the present case, dual-surface Phasix mesh was selected. Its peritoneal coating prevents adhesion to the abdominal viscera, whereas the fascial surface promotes tissue ingrowth and scar formation. Moreover, Phasix mesh is bioresorbable over approximately 2 years, reducing the risk of visceral complications [22].

Our patient underwent vascular intervention first to reduce the risk of thrombosis and thromboembolism; the Spigelian hernia was then repaired. This sequence was selected to minimize the risk of thrombus propagation or embolic events during surgery.

A recent study from Edinburgh reviewed 107 cases of Spigelian hernia over a 10-year period and concluded that a laparoscopic approach is preferable for defects smaller than 5 cm or those with peritoneal components; larger defects are better managed with open surgery [23]. However, current surgical guidelines recommend repair of all Spigelian hernias once diagnosed. Although both open and laparoscopic approaches are safe, laparoscopic repair is associated with lower postoperative complication rates and shorter hospital stays [8]. This approach proved successful in the present case.

Conclusions

This case illustrates the simultaneous occurrence of left common iliac DVT secondary to May-Thurner syndrome and a Spigelian hernia presenting with obstructive symptoms. Successful diagnosis and management of these rare conditions were achieved through interdisciplinary collaboration, advanced imaging modalities, and minimally invasive surgical intervention.