Research Article

Retained Weapon Injuries: An Unusual Presentation with a Good Prognosis

Leire Zarain Obrador*, M Dolores Pérez Díaz, Marta Cuadrado Ayuso, Alejandro Sánchez Arteaga and Fernando Turégano Fuentes
Department of General Surgery, General of Hospital General Universitario Gregorio Marañon, Spain

*Corresponding author: Leire Zarain Obrador, Department of General Surgery, Hospital General, Universitario Gregorio Marañon, Madrid, Spain

Published: 07 Dec, 2016
Cite this article as: Obrador LZ, Dolores Pérez Díaz M, Ayuso MC, Sánchez A. Retained Weapon Injuries: An Unusual Presentation with a Good Prognosis. Clin Surg. 2016; 1: 1224.


Introduction: Retained weapon injuries are unusual but present a diagnostic and therapeutic challenge. The aim of this study was to review our experience in the management of these patients.

Material and Methods: Retrospective review of patients with retained weapon injuries included in our Trauma Registry during a period of 21 years.

Results: Sixteen patients with retained weapon injuries were identified, 13 men and 3 women, with a median age of 45 years (25-88). Nine weapons were in the abdomen, three in the thorax, three in the head, and one in the neck. All patients were hemodynamically stable on admission, and the mean RTS and ISS were of 11.7 and 11, respectively. Surgical approaches included 8 laparotomies, 1 laparoscopy, 1 sternotomy, 1 VATS (video-assisted thoracic surgery), 2 craniotomies, 1 posterior neck exploration, and 2 simple extractions. There was one death, not directly related to the injury, in an 82 y.o. patient with a through-and-through cardiac wound.

Conclusions: Despite their spectacular presentation most patients will be hemodynamically stable, allowing for consideration of minimally invasive techniques in selected patients. Their overall prognosis is good.


A retained weapon injury is that in which the weapon or a part of it is partially embedded in the body [1]. Retained weapon injuries are rare but they can pose a diagnostic and therapeutic challenge, and no established protocols exist for their management [2]. The manipulation or blind removal of the weapon before a careful evaluation can cause a significant bleeding, given a theoretical plugging effect of the weapon over adjacent vessels. Since these injuries are so infrequent, most centers have a very limited experience in their management [1,3]. Our aim was to review our experience in the management of these patients, with the hypothesis that, despite their spectacular presentation, the overall prognosis is good.

Materials and Methods

Retrospective study of patients with retained weapon injuries included in our Trauma Registry from April 1994 to August 2014. We reviewed the demographics, anatomical location, diagnostic studies, trauma scores, surgical approach, and outcome. The following trauma scores were used: ISS (Injury Severity Score), RTS (Revised Trauma Score), and PATI (Penetrating Abdominal Trauma Index).
X-rays were done in all hemodynamically stable patients in order to determine the position of the weapon. When in doubt about a vital organ involvement, a CT scan or CT-angio was done. Patients with a retained weapon injury in the precordial area had also a FAST ultrasound. All patients had the weapons removed in the operating room..
Most patients were managed by the general surgeon on call. Those patients with retained weapons in the head, thorax and heart were managed by the respective specialists.
A review of published series was carried out through a PubMed search.


Sixteen patients with retained weapon injuries were identified from April 1994 to August 2014, representing 4% of the stab wounds in our trauma registry. Demographic data and diagnostic tests are described in Table 1. All retained weapons were visible except for one patient. Only 5 patients had an ISS > 15. All patients but one was operated on under general anesthesia.
Location of injuries, type of weapon, injury, surgical technique, and trauma scores are described in Table 2. All patients but one could be placed in a supine position on the table; the remaining patient was injured at the back of the neck and had to be intubated with fiberoptic bronchoscopy in the sitting position (Figure 1); he was then lied down in prone position. Two of the knives were embedded in bone structures – one in the spine and, the other one in the skull (Figure 2). Two patients developed surgical complications: a deep wound infection (after gastric and transverse colon injury), and an early postoperative bleeding after a pancreatic injury that needed surgery, packing and laparotomy. Only one patient died; he was an 82 year old male with dementia and a self-inflicted cardiac wound by means of a skewer. The heart was sutured through a sternotomy and he recovered well initially but ultimately died from a bilateral pneumonia 20 days after surgery.
Eight patients were lost to follow up. Two patients had late sequelae: the one with the neck wound had a suprascapular nerve injury causing persistent weakness on abduction of the upper limb; the patient injured in his brain and eye suffers from headaches and slow speech.

Table 1

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Table 1
Demographic data and imaging techniques.


Retained weapon injuries are not frequent and most centers have a very limited experience in their management [3]. We only found two published series, a very recent one with 102 cases [1] that proposes a management algorithm, and another one with 33 patients [3], both from South Africa; the rest of publications consist of case reports.
The evaluation of the patient must follow ATLS principles, and the assessment of the location and depth of the weapon can make us suspect possible visceral lesions [1]. The transfer of the patient by the EMS must be careful, with immobilization of the weapon in order to prevent further damage [4].
Around 90%-95% of patients were hemodynamically stable in the two published series, and 100% in our series; this allows for imaging techniques before the extraction of the weapon. A simple X-Ray in two projections was performed in all our patients, and further imaging was only done in doubtful cases. In some cases a CT scan can be of help in establishing possible injuries and anticipating bleeding upon extraction of the weapon [1,3,5].
Retained weapon injuries in the neck and thorax have a higher risk of bleeding upon extraction of the weapon, in view of the possible damage to the heart and blood vessels nearby [5]. An initial CT-angio is advocated by some groups [3], whereas others prefer a simple CT scan, leaving the CT-angio only for cases without “scattering” and when it is considered that it can provide useful additional information. They argue that the distortion effect caused by the weapon is unpredictable, and that it would be convenient to avoid the unnecessary administration of intravenous contrast, in case the patient needs an interventional radiology procedure [1,6].
In the rare case of hemodynamic instability the patient should go directly to the operating room. Nevertheless, hemodynamic stability should not make us underestimate the possible presence of vascular lesions due to the occasional “plugging” effect of the weapon [7]; this is why surgical extraction under direct vision is always required. In our patient with a heart injury caused by a skewer there was no cardiac tamponade, probably because of the small cross section of the occluding weapon.
It is remarkable that in some series simple extraction of the weapon was enough in 50% of cases [3], whereas in our series it was only possible in 2 cases (12.5%). Some locations are very rare but can be life-threatening or can seriously damage organs; transorbital lesions could be an example, of which we only had one case [8-9].
The use of minimally invasive techniques in selected patients can prevent unnecessary laparotomies or thoracotomies. The low incidence of this approach in our series is partly due to the fact that a majority of cases belong to a period prior to the introduction of these techniques in the management of trauma. Our first laparoscopy performed for a retained weapon injury was in 2012, although other laparoscopic approaches had already been performed for penetrating injuries in our centre; however, we believe there may be a concern, at least theoretical, with the possible effects of the creation of pneumoperitoneum in a patient with a retained weapon, in terms of distortion of the anatomy of the injuries. The only patient of our series who underwent VATS had a knife which moved with the heart beats (Figure 3). VATS allowed for the assessment of the integrity of the pericardium and identification of a lung laceration which was repaired with an endostapler. In experienced trauma centers this surgical approach is considered a diagnostic and therapeutic tool for the extraction of the weapon and the assessment of lung, diaphragmatic and pericardic injuries. An endovascular approach can be useful in some cranial lesions [3,10-12].
Retained weapons in the back can pose an anesthetic challenge because of the impossibility of managing them in the supine position, as shown in one of our cases; In some of these complex cases some authors have described the “double table technique”, placing two parallel operating room tables with a space between them, so that the patient can be placed supine, and the object remains in the space between the two tables [3,13,14].
Half of our patients had a history of psychiatric disorder, and the injuries were self-inflicted; in seven there was an aggression, and the other had an occupational accident [15]. This differs from the literature, where most injuries are due to accidental falls over different objects or to motor vehicle collisions, or also to aggressions [16,17].
The main limitation of this study is the small number of patients, although be believe it is the third largest published.

Table 2

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Table 2
Location of injuries, type of weapon, injuries, surgical technique, and trauma scores.

Figure 1

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Figure 1
Intubation with fibrobronchoscopy in a patient with a posterior cervical retained weapon injury.

Figure 2

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Figure 2
Skull retained weapon injury.

Figure 3

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Figure 3
Retained weapon injury in left hemithorax, which moved with the heart beats.


Penetrating injuries with a retained weapon are infrequent in our environment, they are usually self-inflicted, and have a mild-tomoderate severity; they mostly have a favorable outcome, despite their spectacular presentation. Most patients will be hemodynamically stable, allowing for consideration of minimally invasive techniques in selected patients.


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