Ankle Gravity Stress View in the Seated Position: A Technical Tip

Abstract

Category: Ankle Introduction/Purpose: Diagnosis of mortise instability in the apparent isolated lateral malleolus fracture can be challenging and often relies on stress radiography. While the gravity stress view (GSV) is commonly utilized, it traditionally requires the patient to assume the lateral decubitus position for imaging of the ankle. This can be difficult and uncomfortable for the patient and may be unsafe in particular situations. Furthermore, transferring the patient back and forth to obtain this positioning is time-intensive for the radiology technician and disruptive to clinic throughput. Therefore, we describe a simple technique that allows acquisition of the GSV of the ankle while the patient remains seated. The technique involves minimal patient movement and is simple for the staff to position appropriately. Methods: The patient is seated on either a stable office chair with arms for safety or in a wheelchair. The affected limb is then placed on a padded stool with the foot extended past the edge of the stool. The patient is instructed to maintain the ankle in a comfortable resting position. They are then encouraged to externally rotate at the ipsilateral hip. If needed, a small bump can be placed underneath the contralateral hip to further increase external rotation of the affected limb at the hip. The ankle and foot should be approximately 15 degrees internally rotated relative to the plane of the floor once the leg has been appropriately positioned. The leg should be held straight with the ankle at the level of the chair seat. This places the ankle in an optimal angle for obtaining a mortise view. The radiograph is then obtained in standard fashion. Results: N/A Conclusion: Obtaining the GSV in the seated position offers several advantages. First, the patient is placed in a seated position, which is more time-efficient than transferring the patient to the radiology table and avoids the potential danger of patients falling. Second, external rotation of the hip is generally well-tolerated in isolated leg injuries. Third, this positioning more reliably places the ankle in approximately 15 degrees of internal rotation to obtain the optimal mortise view and assess mortise symmetry. Finally, patient comfort is increased as this technique obviates transferring patients or placing their hip directly on a rigid radiology table.