With the widespread adoption of minimally invasive methods and the rapid development of laparoscopic surgery, LC and LCBDE have emerged as pivotal treatment strategies for patients with gallbladder and biliary tract diseases. Compared to open surgery, laparoscopic procedures offer numerous advantages, including smaller incisions, less trauma, faster postoperative recovery, shorter hospital stays, and fewer complications[17-19]. Moreover, ligation clips can effectively seal the cystic duct and blood vessels, improving surgical efficiency. Therefore, ligation clips have been increasingly used in biliary tract surgery. Initially, metallic titanium clips were adopted, but these clips were found to loosen, detach, migrate, and cause significant pathological changes in the surrounding tissues. In 1999, non-absorbable polymer Hem-o-lok clips were developed and introduced into laparoscopic surgery, demonstrating good sealing and biocompatibility. Hem-o-lok clips feature integrated anti-slip teeth, arched prongs, and flexible hinges, providing flexibility and secure ligation while minimizing interference with postoperative CT and MRI examinations[20]. Hence, Hem-o-lok clips are widely used in laparoscopic biliary surgery[21]. Despite the large number of laparoscopic gallbladder and biliary surgeries performed globally each year, reports of postoperative clip migration are rare, with only occasional cases mentioned.

The PubMed, Web of Science, MEDLINE, and Scopus databases were searched from 2013 to July 2024 using the keywords “clip migration and laparoscopic cholecystectomy or clip migration and LCBDE.” After screening, 17 articles were identified, describing 30 cases of Hem-o-lok clip migration following LC and/or LCBDE[7-16,22-27] (Table 1). Among previous laparoscopic surgeries, 14 cases involved both LC and LCBDE (47%), while 16 cases involved LC or LCBDE alone (53%). The patient ages ranged from 31 to 88 years. The time of migration ranged from 6 weeks to 4 years post-LC and/or LCBDE. Among these, 8 patients remained asymptomatic and were diagnosed as an incidental finding during surgical cholangioscopy or ERCP. The most common manifestations of clip migration were symptoms of acute cholecystitis and CBD obstruction, such as abdominal pain, fever, and chills. Some patients presented with jaundice, which was differentiated from non-iatrogenic CBD stones, or anemia, which required investigation for duodenal ulcers. In the 24 cases, the clips were wedged in the CBD. In three cases, the clips became part of the T-tube tract; in another three cases, the clips migrated into the duodenum. Most migrated Hem-o-lok clips were treated with surgical cholangioscopy or ERCP stone extraction, while clip migration into the duodenum was managed by endoscopic removal or observation.

The exact mechanism underlying Hem-o-lok clip migration after laparoscopic biliary surgery remains incompletely understood. Based on previous literature, several possible mechanisms can be hypothesized. First, incomplete closure of the cystic duct may lead to the formation of a bile tumor, causing clip migration[7,8,25]. Second, surrounding structures may exert pressure on the clip[14,15,22]. Third, inflammation and necrosis of the tissue around the clip may result in fistula formation, leading to erosion of the BD wall, causing the clip to enter the CBD or even the duodenum. Additionally, the clip itself may also trigger an immune rejection reaction and infection, resulting in migration[11,12,14,16,22,27]. Fourth, improper surgical techniques, including excessive or incorrectly placed clips, may damage the BD and surrounding structures, accelerating migration[13]. Fifth, certain anatomical factors might affect the stability of the clip[10,15,28]. Finally, increased abdominal pressure or exacerbation of pre-existing pathological conditions in the patient may affect the stability of the clip, leading to migration[13]. In this study, 1 patient had an ectopic clip in the T-tube sinus tract, which may be due to the clip being placed too close to the T-tube sinus. In another patient, the migrated clip was found in the CBD, possibly due to increased fragility of the BD wall caused by local inflammation around the clip. Moreover, the clip itself is a foreign object and may elicit a rejection reaction.

Hem-o-lok clip migration in the BD typically does not cause noticeable symptoms in the early stages. Abdominal discomfort may only occur when clamping the T-tube before its removal. Furthermore, the long-term presence of a Hem-o-lok clip in the BD can alter BD motility, potentially becoming a site for gallstone formation and possibly causing cholangitis. Clip migration to the duodenum may cause duodenal ulcer and perforation, presenting clinical manifestations similar to other conditions, such as CBD stones, cholangitis, or duodenal ulcers[29]. Preoperative imaging studies such as CT and MRI often cannot clearly distinguish between Hem-o-lok clips and stones, requiring surgical cholangioscopy or ERCP. Patients with clip migration to the duodenal bulb may manifest atypical clinical symptoms. Hence, for patients undergoing LC or LCBDE who present with recurrent abdominal pain, clinicians should be aware of the possibility of Hem-o-lok clip displacement and consider scheduling CT scans and gastroscopy[16]. Notably, all types of surgical clips carry a risk of migration. Due to the lack of specific clinical symptoms and imaging features, clip migration is often confused with CBD stones or duodenal ulcers, potentially misleading physicians and causing delays in diagnosis and treatment.

With the rapid development of endoscopic technology, ERCP and cholangioscopy have emerged as the preferred methods for managing clip migration, offering advantages such as speed, cost-effectiveness, minimal invasiveness, and fewer complications[11,14,15,26]. According to the article, preoperative ERCP combined with LC is associated with a higher rate of CBD stone clearance and a lower rate of postoperative bile leakage compared to LCBDE + LC, while LCBDE + LC may be associated with shorter hospital stays[7,30]. In this study, 1 of the 2 patients had the migrated clip identified and removed through the sinus tract via cholangioscopy, as the T-tube had not yet been removed. The other patient presented with significant symptoms 17 months post-surgery, and had the clip removed via ERCP without the need for a CBD incision, resulting in less trauma and faster recovery. According to previous research, Hem-o-lok clips migrated into the CBD should be removed regardless of symptoms[7,8,22,23]. For clips migrated into the duodenum, symptomatic cases should be managed endoscopically or surgically, while asymptomatic cases may consider conservative treatment[16]. Therefore, treatment plans should be individualized based on the patient's condition to optimize safety, while minimizing trauma and medical resources.

Although reports of Hem-o-lok clip migration into the biliary tract are relatively rare, the increasing use of Hem-o-lok clips in laparoscopic biliary surgery has led to a gradual rise in such cases, which warrants our attention. Surgeons should be vigilant in employing proper techniques, selecting clips appropriately, or exploring alternative methods. In patients with a history of LC or LCBDE who present with biliary colic, cholangitis, or abdominal discomfort, clip migration into the biliary tract or other body parts should be considered a differential diagnosis. Further research will provide a deeper understanding of this postoperative complication, promoting the development of more suitable solutions.