The increased utilization and accessibility of nail guns have been accompanied by a parallel increase in the number of emergency department visits resulting from nail gun-related accidents in both consumers and construction workers [1]. Primary injuries tend to be located in the upper extremities, particularly the hands and digits, although numerous case reports have described facial, cranial, and low cervical injuries. However, a paucity of literature exists regarding high cervical spine injuries with vertebral artery involvement [1–6]. Here, we report a rare case of a high cervical spine nail gun injury with unilateral vertebral artery involvement treated with vertebral artery embolization and subsequent removal of the nail projectile.

Vertebral artery involvement is highly uncommon in patients with penetrating trauma, estimated at 0.5% of all cases [7]. The vertebral artery is relatively more likely to be affected in cases of blunt injury to the cervical spine or hyperextension of the neck with lateral flexion. The anatomic course of the vertebral arteries through the transverse foramina of the cervical vertebrae makes the management of patients with penetrating injuries quite intricate. In such cases, it is crucial to quickly assess the extent of vascular involvement through techniques such as CT angiography. Blind disturbance of the embedded projectile could lead to significant bleeding that would be quite difficult to manage, even surgically, as proximal and distal control of the vertebral arteries is challenging to achieve. Additionally, initial imaging can help assess the type of nail(s) embedded in the tissue, as the presence of a barbed nail or a nail with a washer could alter the treatment approach [8].

Once the initial imaging evaluation has been completed, secondary imaging to be performed includes diagnostic angiography, which allows a more focused assessment of the treatment approach. For a penetrating injury threatening a high cervical portion of the vertebral artery, an endovascular approach is the most appropriate. Numerous articles have highlighted the safety and effectiveness of endovascular embolization in treating grade I to grade V vertebral artery injuries, whether iatrogenic or trauma-induced [9–11]. Embolization proximal and distal to the site of injury is the recommended method, as it minimizes potential bleeding as the foreign object is extracted. This approach is ideal for nail penetration injuries, as the nail can be regarded as a low-velocity projectile. Thus, tissue damage is localized along the trajectory of the nail, unlike with a high-velocity projectile such as a bullet, which causes extensive damage to surrounding tissue due to cavitation [12,13]. Final assessment of vessel embolization also remains important; another case series discussing endovascular treatment of vertebral artery injuries saw only an 89% rate of immediate total occlusion [9]. Notably, the reliance on interventional radiology for treating penetrating vertebral artery injuries requires a facility with the necessary equipment. When a penetrating vertebral artery injury occurs in a rural setting, the extent of the injury must be assessed to determine patient stability for transport to a tertiary care center. Surgical treatment of a penetrating vertebral artery injury is possible and has been documented, but this has generally been reserved for cases involving uncontrolled bleeding, suspected spinal cord injury, or vertebral instability [8,14].

When pursuing endovascular rather than surgical treatment for a penetrating injury, particularly with bony involvement as in the present case, assessing the stability of the cervical spine after removal of the foreign object is also of extreme importance. The cervical spine is much more susceptible to biomechanical instability than the thoracic spine, and extra precautions must therefore be taken in cases of projectile injuries. Thus, we obtained postoperative upright cervical spine X-rays to ensure general spinal stability. If possible, an MRI scan should also be obtained for a more precise examination of the stabilizing ligaments in the cervical spine. In particular, the atlantooccipital junction and atlantoaxial joints should be localized, as these are regions at high risk of injury in cases like the present one.

Finally, when dealing with uncommon mechanisms of purportedly accidental injury, the shape of the penetrating nail can hint at a potential cause, with bent nails suggesting a ricochet. In contrast, injuries involving straight nails, as in the present case, could result from a non-accidental or an accidental discharge. The location of the injury can also suggest a primary mechanism; upper extremity injuries are most likely to be due to accidents, while cranial/intracranial, cervical, or abdominal involvement is much more likely in cases of attempted self-harm [15]. An injury side corresponding with patient handedness may also increase the suspicion of self-harm. Cervical nail gun injuries appear to be quite a rarity in the published literature, and thus, little can be deduced from the location of the injury in the present circumstance. Detailed history taking and, if possible, cross-referencing with witnesses may be the only tools available to discern cause.

Cervical nail gun injuries are uncommon in the literature, particularly cases in which the projectile threatens a vertebral artery. Here, we present a case of such an injury, adding to the evidence suggesting that vertebral artery embolization prior to foreign body removal is a safe approach to treating nail gun-related injuries to the vertebral artery. In addition, we stress the importance of assessing the mechanical stability of the cervical spine via both upright cervical X-ray and cervical MRI postoperatively.