Log in Sign up
Cart

SAEM Clinical Image Series: Finger Pain

Posted by Grace Lagasse, MD on

The patient is a 24-year-old female who presents to the emergency department for left middle finger pain and swelling. She is right hand dominant and works in a kitchen. The patient states that ten days ago she avulsed the distal tip of the left middle finger, including the majority of the nail. At that time, the patient was evaluated at an outside hospital where the wound was cauterized with silver nitrate due to soft tissue bleeding. Since then, the patient states that she has had swelling over the dorsal distal phalanx.

Additional Images

Physical Exam

General: Alert, awake, oriented, and non-toxic without acute distress

Extremities:

  • The left third digit is minimally swollen without significant erythema or drainage from the wound.
  • There is brisk capillary refill over the volar aspect of the digit.
  • The patient is able to fully flex the digit.

The remainder of the exam is unremarkable.

Laboratory Data

White Blood Cells: 6.7 cells/mm3

Erythrocyte Sedimentation Rate: 2 mm/hr

C-reactive Protein: 1.2 mg/L

Labs were otherwise normal.

Case Question: What is on the differential diagnosis list to explain the X-ray images?

  • Distal phalanx fracture
  • Retained foreign body
  • Silver nitrate
  • Osteomyelitis

Case Question: Based on the history and physical exam, what is the likely etiology of the X-ray findings?

Silver nitrate

The X-ray image shows a radiopaque density over the third distal phalanx. This is due to the silver nitrate that was used to cauterize the patient’s wound when she initially presented. The staining of the patient’s skin from the silver nitrate can be seen in the photo, which correlates with the areas of radiopacity on the X-ray.

Case Discussion

Take-Home Points

  • Silver nitrate is a common topical chemical cautery agent used to achieve hemostasis in soft tissue injuries. On the X-ray and computed tomography (CT) imaging, silver nitrate can appear as a radiopaque foreign body due to silver deposits in the tissue.
  • It is important to know this characteristic of silver nitrate to avoid a misdiagnosis of retained foreign body and to prevent unnecessary surgical exploration. If silver nitrate is used for hemostasis before imaging is obtained it should be well documented and communicated to radiology.

References

  1. Tong, S. H. Y., W. L. Chan, and Y. L. Lee. “Silver nitrate stain masquerading as an avulsion fracture of the finger.” Hong Kong Journal of Emergency Medicine (2011): 47-49. DOI
  2. Healy, Claragh, et al. “Silver nitrate masquerading as a radiopaque foreign body.” Emergency radiology (2007): 63-64. PMID: 17342469
  3. Madan, Sunil I., and Katherine L. Heilpern. “Silver nitrate as a radiopaque foreign body.” Journal of Emergency Medicine (1999): 1045. PMID: 10595894
  4. Livingstone, Devon, et al. “Silver nitrate mimicking a foreign body in the pharyngeal mucosal space.” World journal of radiology (2015): 100. PMID: 26029352
  5. Narayan, N., et al. “The misleading appearance of silver nitrate on plain radiography.” The Annals of The Royal College of Surgeons of England (2014): e3-e4. PMID: 24780777

Copyright

Images and cases from the Society of Academic Emergency Medicine (SAEM) Clinical Images Exhibit at the 2020 SAEM Annual Meeting | Copyrighted by SAEM 2020 – all rights reserved. View other cases from this Clinical Image Series on ALiEM.

Author information

Grace Lagasse, MD

Global Health Fellow
Department of Emergency Medicine
University of Cincinnati Medical Center

|

The post SAEM Clinical Image Series: Finger Pain appeared first on ALiEM.

Go to full site