Execution
- 1Position the patient supine or long sitting with the ankle in a consistent neutral position.
- 2Place a tape measure at a standardized starting point over the ankle.
- 3Wrap the tape in a figure-of-8 path around the malleoli, heel, and dorsum of the foot using the same landmarks each time.
- 4Read the circumference without compressing the soft tissue.
- 5Repeat the measurement as needed and compare with the opposite ankle or previous baseline.
Positive outcome
A larger figure-of-8 circumference compared with the opposite side or prior baseline indicates ankle swelling. The test does not identify the cause of swelling. Change over time is often more useful than a single value.
Studies
| Study | Reliability | Sn | Sp | LR+ | LR− |
|---|---|---|---|---|---|
| Tatro-Adams et al. (1995) | Inter-tester ICC 0.99, intra-tester ICC 0.99 (3 testers, n=50 healthy) | NA | NA | NA | NA |
| Brodovicz et al. (2009) | peripheral edema feasibility and reliability study | NA | NA | NA | NA |
CommentFigure-of-8 measurement is a reliable swelling measure when landmarks and tape tension are standardized. It is useful after ankle sprain, fracture, surgery, or inflammatory flare, but it is not diagnostic of the underlying lesion. Repeat with the same method for meaningful comparison.
Low Clinical Value