Execution
- 1Ask about mechanism, especially forced dorsiflexion with external rotation, eversion, or twisting on a planted foot.
- 2Observe weight-bearing tolerance, gait, swelling, bruising, and whether pain is higher than a typical lateral ankle sprain.
- 3Palpate the anterior inferior tibiofibular ligament, interosseous membrane, posterior tibiofibular region, and deltoid region.
- 4Ask about pain with running, cutting, pivoting, stairs, or push-off.
- 5Integrate history, palpation, functional limitation, and stress tests before deciding whether imaging or referral is required.
Positive outcome
A positive clinical picture includes anterolateral or syndesmotic pain, tenderness over the AITFL or interosseous membrane, pain with weight bearing, and a compatible dorsiflexion/external-rotation mechanism. Prolonged recovery compared with a simple lateral ankle sprain supports suspicion. No single symptom is definitive.
Studies
| Study | Reliability | Sn | Sp | LR+ | LR− |
|---|---|---|---|---|---|
| Sman et al. (2013) — Pain out of proportion to apparent injury | prospective diagnostic accuracy, n=87, MRI reference | 65 | 79 | 3.05 | 0.45 |
| Sman et al. (2013) — Inability to single-leg hop | NA | 89 | 29 | 1.25 | 0.37 |
| Sman et al. (2013) — Inability to walk after injury | NA | 89 | 21 | 1.13 | 0.51 |
| Sman et al. (2013) — Pain in shank/knee during injury | NA | 50 | 70 | 1.68 | 0.71 |
| Sman et al. (2013) — Local syndesmosis ligament tenderness | NA | 92 | 29 | 1.29 | 0.28 |
| Sman et al. (2015) | prospective diagnostic study | NA | NA | NA | NA |
CommentSyndesmosis injury is a clinical pattern rather than a single positive sign. Sman 2013 against MRI reference found high-sensitivity findings (inability to hop, inability to walk, ligament tenderness — all ~90% Sn but low specificity) and high-specificity findings (pain out of proportion to injury — 79% Sp, LR+ 3.05). The recommended approach is to combine a sensitive sign for screening with a specific sign for confirmation. Systematic review evidence shows clinicians should not rely on one test alone, and MRI or other imaging may be needed when the diagnosis affects management.
Moderate Clinical Value