Page 67 - Journal of Special Operations Medicine - Summer 2014

literature and reports of death are not substantiated sites of foreign body reaction. Pain is usually positional
6
with evidence. 1,2,4–6,8–10 and worsens when direct pressure is applied over the
retained spines. Most spines are radiopaque and can
1
Late symptoms are related to retention of spine fragments be visualized on plain radiographs or axial imaging
8,9
within the soft tissues and include hyperkeratosis, gran- such as computed tomography. The usefulness of ul-
uloma formation, fungal or bacterial infections, chronic trasound and magnetic resonance imaging is unclear.
arthropathy, neuropathy, and vesicle formation. 10–12 Surgical excision should be considered for refractory
symptoms and chronic wounds only, and not empiri-
cally undertaken only for the removal of an incidentally
Management
found retained spine. The mainstay of therapy has been
There is little in the medical literature about the acute surgical excision of each retained spine and, occasion-
care of sea urchin injuries. A variety of “remedies” for ally, the surrounding fibrotic reaction as well. Postop-
sea urchin injuries can be found. Removal of visible erative cosmesis can be a significant issue depending on
spines will cause the local reaction to subside and may the anatomic wound location, the number of spines, and
dramatically improve symptoms. the need for en bloc excision in case of multiple spines.
Some authors have reported on cryotherapy and laser
Puncture injuries, without retained spines, are effec- disintegration; however, more data are needed to sup-
tively treated by symptomatic relief. Immersion in water port the overall cosmetic result. 15–17
(110–115°F) mixed 1:1 with vinegar is reported to in-
activate toxin and provide immediate pain relief in case
of envenomation, although aggressive cleansing of the Case Presentation
wound with warm soap and water may be equally effec- A 21-year-old Sailor backed up into a sea urchin during
tive. The exact mechanism of symptom improvement training activities. Spines made contact with her lower
1–6
with either treatment is poorly understood and may rep- thoracic and lumbar posterior skin areas. The patient
resent neuroattenuation of afferent nociceptive neurons. immediately experienced an intense burning sensation.
Tetanus toxoid prophylaxis is recommended. Retained A bystander manually removed several spines that were
1
spine fragments can carefully be removed if visible and protruding through the skin. The patient cleansed the
protruding through the skin, in order to stop the ongoing wound with soap and water, which improved but did
envenomation. This may significantly improve symp- not eliminate her pain. A physician attempted to re-
2–6
toms. Pain, which may be intense is pressure is applied move more of the spines with forceps, but the patient
to the wound (such as continued ambulation of a foot reported feeling them break off just below the skin level.
wound as may be required during military operations), The patient was not offered antibiotic prophylaxis and
can be treated with nonsteroidal anti-inflammatory was given narcotics for pain. The pain resolved over the
agents and, in some cases, opioid agents. 1 following 72 hours, and the patient returned home to
the United States. Of note, the patient has no signifi-
cant past medical or surgical history, was not taking any
Complications
medications, and has no allergies.
Infection may uncommonly develop at any time; although
most infections likely are secondary to human skin flora, Over the subsequent 12 weeks, the patient developed
marine flora such as Mycobacterium marinum, Vibrio intermittent, sharp, burning pain episodes in the back,
parahaemolyticus, and Vulnificus spp. should be consid- localized to the areas previously impaled with the sea
ered potential wound contaminants. This is less likely urchin spines. The patient presented to our institution
13
because some spines are commonly coated with an an- for consultation and surgical excision. On examination,
timicrobial biofilm. Consideration of broad-spectrum seven areas of intense, focal pain could be elicited on
14
antibiotic prophylaxis should be based on degree of in- palpation of small skin lesions (Figure 1). Computed to-
jury and patient factors such as diabetes, immunocom- mography scanning revealed several retained sea urchin
promised states, and ability to care for the wound and spines and associated surrounding inflammatory reac-
keep it clean. This last factor (keeping the wound clean) tions (Figure 2).
may prove the most challenging during military opera-
tions, and antibiotic prophylaxis should be considered After consideration of several treatment options, includ-
under these circumstances. Any antibiotic that broadly ing en bloc excision of all spines and surrounding tissue,
covers skin flora, gram-negative rods (Vibrio spp.), and laser ablation and removal, and continued symptom-
M. marinum can be considered. atic nonoperative management, the patient elected to
be taken to the laser ablation suite. Topical 23%:7%
Patients with occult retained spine fragments will initially lidocaine/tetracaine gel was applied to the back, over
recover and eventually develop chronic pain around the all the suspected sea urchin spine sites, based on local

Treatment of Sea Urchin Injuries 57