|
Year |
2007 |
|---|---|
|
Question Number |
39 |
|
Category |
Musculoskeletal Trauma |
Question
A 24-year-old man sustains a bimalleolar ankle fracture. Which of the following is considered the most reliable means of predicting a tear of the interosseous membrane?
1- The level of the fibular fracture
2- The presence of an associated talar dislocation
3- The Lauge-Hansen fracture type
4- The result of an intraoperative stress test
5- Widening of the medial clear space
Figures
Answer (click for answer)
Answer – 4- The result of an intraoperative stress test
The interosseous membrane is a component of the ankle syndesmosis, a critical factor in ankle stability. The interosseous ligament is a part of the interosseous membrane and has been described as the strongest portion of the syndesmosis The interosseous ligament should remain intact in supination external rotation patterns and is torn during the second stage of pronation external rotation fracture patterns. Nielson et al show that the level of the fibular fracture does not correlate reliably with the integrity or extent of interosseous membrane tears identified on MRI. The study supports the need for intraoperative stress testing of ankle syndesmosis in all operative fractures. The other answer choices can increase suspicion of interosseous membrane tear, but directly stressing the syndesmosis in the operating room is the most reliably predictable method of diagnosis.
Reference: