Diagnosis of Wooden Foreign Bodies in the Finger

Initial Diagnostic Approach

The American College of Radiology recommends radiographs of the area of interest as the first imaging study for suspected foreign bodies in the finger, with multiple views to maximize detection 3, 2
Wood is radiolucent on radiographs, unlike metal, stone, and glass which are radiodense and more easily detected 4, 1
If initial radiographs are negative but a wooden foreign body is still suspected based on history and examination, further imaging is necessary 3, 5

Ultrasound is the imaging modality of choice for detecting wooden foreign bodies when radiographs are negative, with a reported sensitivity of 95% for foreign body detection 1, 2
The American College of Radiology states that all foreign bodies appear hyperechoic on ultrasound with some degree of posterior acoustic shadowing 2
Ultrasound allows for characterization of foreign body morphology, depth, and relationship to adjacent structures 2
Ultrasound can provide real-time guidance during removal procedures 7

The American College of Radiology reports that CT has high sensitivity for detection of foreign bodies and is 5-15 times more sensitive than radiography 4, 1
CT is superior to MRI in identifying water-rich fresh wood 3, 8
CT can precisely localize foreign bodies and determine their relationship to surrounding structures 1
For comparable studies regarding foreign bodies in the feet, CT has 63% sensitivity and 98% specificity 3, 8

The American College of Radiology states that MRI has lower sensitivity compared to CT and ultrasound for foreign body detection 3, 8, 2
For foreign bodies in the feet, MRI has 58% sensitivity and 100% specificity 3, 8
On MRI, wooden foreign bodies are usually low signal on all sequences and demonstrate non-anatomic morphology 1
MRI may be useful in detecting complications such as surrounding edema, inflammation, or abscess formation 3, 8

Wood foreign bodies can cause granulomatous reactions and superimposed soft tissue infections including cellulitis, abscess, myositis, or sinus tract formation 4, 1
Hand surgeons should be consulted due to the risk of damage to tendons, nerves, and blood vessels during removal 2
Chronic pain, inflammation, and infection can develop even months after the initial injury if wooden foreign bodies are not completely removed 2