Keywords
arrow injury - penetrating injury - missile injury
Introduction
Since the advent of modern era weapons and artillery, penetrating injuries by old
world missiles, such as arrows, lances and spears have only been rarely reported in
the medical literature, especially in the Western world. Few cases of arrowhead injuries
have however been reported from the Indian subcontinent, especially from the tribal
areas. Very few of these cases describe central nervous system (CNS) injuries caused
by fired arrows. Arrowhead injuries depend on the type of bow and arrow used. An important
determinant of severity of injury caused by an arrow, as of any other missile injury,
is the velocity of the missile. The average velocity of a bow-fired arrow is approximately
60 to 90 m/s.[1] The extent of injury and soft and bony tissue destruction also depend on the size,
shape and aerodynamic stability of the arrow. We report three cases of arrowhead injury
of the head and spine and discuss their management.
Case 1
A 65-year-old female patient presented to our emergency room following penetrating
trauma to her head by an arrow fired by her psychotic son. She complained of pain
at the site of injury and nasal bleeding. There was no history of loss of consciousness,
vomiting or convulsions. On initial examination, she was conscious with a Glasgow
coma scale (GCS) score of E4V5M6 and stable vitals. An arrowhead was impacted on the
forehead 5 cm above the nasion, lateral to the midline on the right, with the direction
of impact being downward, laterally and toward the posterior (
[Fig. 1]
). Ophthalmological examination and complete neurological assessment were unremarkable.
An emergency bedside X-ray of the skull revealed the orientation and trajectory of
the foreign body sparing the brain parenchyma (
[Fig. 2]
), which was later confirmed on a CT scan of the head. Surgery was offered to the
patient and her family, to which they agreed. A regional craniectomy was performed
around the site of penetration to permit the arrow free from the bone and facilitate
its gentle extraction in the line of its trajectory, following which the wound was
inspected under direct vision for any bleeding or cerebrospinal fluid (CSF) leak.
Extended craniectomy revealed a breached dura. Duroplasty was performed with autologous
tensor fascia lata graft, and the wound was closed in layers after securing hemostasis.
The postoperative period was uneventful. The patient received broad-spectrum antibiotics
and was discharged on the ninth day postoperatively. At 6 months follow-up after surgery,
the patient was asymptomatic and clinically normal.
Fig. 1 Figure showing arrow injury of the forehead.
Fig. 2 X-rays showing arrow injury and its trajectory in the head. (A) AP view. (B) Lateral view.
Case 2
A 70-year-old male patient came to our emergency room following penetrating trauma
to the upper back by an arrow that was fired by his relative over a family dispute.
On examination, the patient was conscious (GCS E4V5M6) with stable vitals. An arrowhead
was seen impacted on the upper back, 3 cm from the midline, on the right side, and
at the level of D4–D5vertebrae, with the direction of the impact being medially and
anteriorly toward the cord. On examination, power in both lower limbs was Grade 0/5,
tone was increased, all reflexes in lower limb were exaggerated, and plantar bilaterally
upgoing. Sensation below the xiphisternum was absent bilaterally. Position and vibration
sense in lower limbs were absent. Bladder and bowel incontinence were present. CT
scan of thoracic spine (
[Fig. 3]
) demonstrated the trajectory of foreign body and the extent of trauma to the spinal
cord. With consent of the patient and his family members, he was taken up for immediate
removal of the offending arrow. Following a midline skin incision at the back from
D2–D6 (
[Fig. 4A]
), paraspinal muscles were separated and the arrowhead was visualized to be impacting
the bony lamina at the level of D4–D5, subsequent to which laminectomy was performed
to make it free from the bone for gentle extraction of the arrowhead in its line of
trajectory (
[Fig. 4B]
). The wound was inspected under direct vision. Dura and underlying spinal cord were
found to be damaged with no active bleeding; however, CSF was seen leaking through
the compromised dura. After thorough irrigation with normal saline, the dura was repaired
in water-tight fashion and the wound was closed in layers. The postoperative period
was uncomplicated, and the patient was discharged with Foley's catheter in situ on
the 11th postoperative day with Grade ⅕ power in both lower limbs and hyperesthesia.
Follow-up after 6 months showed improved power to Grade ⅗ in both lower limbs, but
bladder and bowel incontinence persisted.
Fig. 3 CT scan showing arrow injury and its trajectory in the back. (A) Axial view. (B) Sagittal view.
Fig. 4 (A) Figure showing intraoperative photograph of spine arrow injury. (B) Figure showing extracted arrowhead.
Case 3
A 14-year-old female came to our emergency room following penetrating trauma by an
arrow fired during play (
[Fig. 5A]
). She was conscious (GCS E4V5M6). There was no history of loss of consciousness or
seizures. The patient, however, had vomited twice after the injury. On examination,
the arrow was seen penetrating the skull over the right frontal region. CT scan of
the brain showed that the arrow was in the right frontal bone not piercing the dura
(
[Fig. 5B]
). The brain parenchyma was normal. The patient was taken to the operating room for
removal of the arrow. Under local anesthesia and sedation, the arrowhead was pulled
out through a narrow craniectomy. The wound was cleaned with hydrogen peroxide and
betadine, and the skin was closed in layers. The postoperative period was uneventful,
and the patient was discharged the following day. The patient was conscious at the
time of discharge and without any neurodeficit. The patient came for follow-up for
6 months.
Fig. 5 (A) Figure showing photograph of arrowhead injury over the forehead. (B) CT scan showing arrow injury piercing the right frontal bone.
Discussion
Arrow injuries are an extinct mode of injury in the Western world but off and on it
is encountered in the tribal areas of India, sometimes unintentional while hunting,
and quite often charged on purpose, but also merely while playing, as was seen in
one of our cases. A rare case of suicide by arrowhead has also been reported.[2] Most of the arrow injuries involve the thorax and abdomen.[3] Arrow injuries to head are rare and mostly involve the face.[1]
[4] However, those involving the CNS are fairly uncommon, although a few cases have
been reported.[5]
[6]
[7]
The mechanism of injury caused by fired arrow is similar to injuries caused by low-velocity
missiles. Arrows have a considerable penetrating capacity in soft tissue and flat
bones. Arrow injuries are usually less destructive than those caused by high-velocity
missiles because of their lower velocity and energy. Barbed arrows are an exception
because of the risk of extensive damage to major structures when retrieved.[8] An arrow injury to the brain may be considered intermediate between a gunshot wound
and stab wound. Size, shape, aerodynamic stability, and velocity of the missile are
important factors which decide the severity of injuries by arrows. The size of the
arrow in the second case was 17 cm and it had penetrated the spinal cord to a depth
of 10 cm (
[Fig. 4B]
). In the first case, 6 cm of the arrowhead had penetrated the skin. In the third
case, the arrow had penetrated the frontal bone but had not crossed the inner table.
Radiography of the skull is helpful in demonstrating the intracranial course of metallic
materials, but the radiodensity of wood is nearly the same as that of soft tissue
and the brain, so it can be difficult to detect.[9] CT is valuable for detecting wooden foreign bodies as hypodense mass.[10] Wooden bodies also appear hypodense on T1- and T2-weighted MR imaging.[11] However, it has also been observed that the CT and MR imaging properties of a wooden
foreign body can change in vivo after a long period of intraparenchymal retention.[12] However, in most cases, a CT scan would provide valuable information about the course
of injury and the depth of penetration of the arrowhead. There is a report about an
unusual head trauma in an adult due to an accidental pressure cooker explosion, where
the patient did not have any focal neurological deficit but had experienced debilitating
headache and multiple episodes of vomiting.[13] A pneumocephalus was seen on CT, and the consequent raised intracranial tension
was deemed responsible for the presenting symptoms, which subsided over 2 days along
with the resolution of the air pocket as confirmed by a repeat CT. Such complications
might also accompany a penetrating injury of the brain, and their presence on a CT
could provide an answer for the accompanying symptoms of headache and/or vomiting.
CT angiography of brain helps to evaluate the extent of cerebrovascular trauma. Injuries
such as arterial dissection, pseudoaneurysm, arterial or venous thrombosis and arteriovenous
fistula can be successfully identified and repaired.[14] If vascular injury is suspected, a CT angiography will be life-saving. An arrow
should never be removed from a patient, irrespective of stability, unless injury to
major vessels has been ruled out.[15] It may be emphasized that arrow removal is not suggested unless in an emergency
trauma care facility. Prompt extraction is advised only under direct vision, keeping
in mind the tamponade effect which may be encountered by the major vessels that may
then subsequently bleed.
Management of arrow injury to the CNS should aim at prevention of infection, exploration
for potential dural tears, and subsequent CSF loss, leading to intracranial hypotension
and minimizing the secondary injuries that may be caused by the missile. The patient
should be immobilized well before and during the transfer to a hospital, especially
if the arrow is unstable. Another important strategy is early extraction of arrowhead
to minimize neurological deficits but should be removed only at a center where adequate
facilities to control hemorrhage are available.[6] Arrow injuries are reported to have 1.4% infection rate.[3] Broad-spectrum antibiotic coverage is instituted to prevent infection.
Another complication of penetrating brain injury is the occurrence of posttraumatic
seizures. The incidence of posttraumatic seizure is higher in penetrating brain injuries
than with closed brain injuries and occurs in over 50% penetrating trauma cases over
a follow-up period of 15 years.[16] Hence, patients must be informed about the possibility, and a proper plan for regular
follow-up should be discussed with them.
Speech problems may also occur as a part of penetrating brain injuries. There was
a case which consisted of a man presenting with an arrow lying in the brain at the
left parieto-occipital region through the right frontal lobe accompanied with intraparenchymal
hematoma[7]. He had motor aphasia at presentation which persisted after the surgical removal
of the arrow. Once intracranial vascular injuries were ruled out by MR angiography,
he was discharged on the second week of the event with severe motor aphasia. With
the help of intensive speech therapy, he had begun to talk in the first month by using
simple words. So, a consultation with a speech therapist can be considered to treat
any difficulty with speech the patient might experience postoperatively.
Pediatric age group patients are more prone to secondary brain insult, requiring better
attention and timely intervention. They are more susceptible to the secondary insult
of brain from low-oxygen saturation, fluid imbalances, electrolyte disturbances, fever,
and seizures requiring special care.[17] Factors affecting the good outcome are amount of contamination, presence of dural
breach, trauma-surgery time gap, quality of wound debridement, and appropriate and
timely antibiotic and antiepileptic medication.[18]
[19]
[20]
