{
 "serie": "s201_STIR_SAG",
 "n_imgs": 18,
 "s": 34.9,
 "respuesta": "**Limited review:** Findings are based only on the 18 supplied sagittal STIR images. Cartilage, individual ankle ligaments, and tendon split tears cannot be reliably assessed without the remaining sequences and planes.\n\n### Abnormal findings\n\n| Location | Description | Confidence |\n|---|---|---|\n| **Inferior talar neck/sulcus tali, adjacent to the sinus tarsi** | Focal lobulated, markedly STIR-bright signal. This appears at least partly cystic, with possible intraosseous extension into the inferior talar neck and adjacent sinus-tarsi fluid/edema. A ganglion or subcortical cystic change is a consideration; the precise intraosseous versus extraosseous extent is not established here. | **Medium** |\n| **Tibiotalar joint** | Small effusion, visible in the anterior and posterior recesses. | **High** |\n| **Subtalar joint** | Small amount of fluid, most evident posteriorly and toward the sinus tarsi. | **Medium** |\n| **Posteromedial ankle flexor tendon sheaths** | Fluid surrounding portions of the medial flexor tendons, particularly the flexor hallucis longus region. This may represent mild tenosynovitis, although some may communicate with the ankle joint. No definite tendon discontinuity. | **Medium** |\n| **Periankle and dorsal foot soft tissues** | Mild subcutaneous/interstitial edema, including the dorsal foot and anterior ankle, with mild edema in the pre-Achilles/Kager fat region. No discrete drainable collection is evident. | **Medium** |\n\n### Other assessed structures\n- **Bones:** No definite acute fracture, collapse, or extensive marrow edema. Apart from the focal inferior talar-neck finding above, no convincing major osseous abnormality.\n- **Cartilage:** No gross talar-dome osteochondral defect or advanced tibiotalar cartilage loss identified; subtle defects cannot be excluded.\n- **Achilles tendon:** Preserved continuity and caliber, without a visible tear.\n- **Plantar fascia:** No convincing thickening or perifascial edema at the calcaneal origin.\n- **Other tendons:** No definite full-thickness tear in the visualized flexor, extensor, or peroneal tendons. Assessment for tendinosis or longitudinal splitting is limited.\n- **Ligaments:** The lateral ligament complex, syndesmosis, deltoid, and spring ligament are insufficiently delineated to confidently diagnose or exclude injury on this series alone.\n\n**Principal finding:** Focal cystic-appearing signal at the inferior talar neck/sinus tarsi, accompanied by small ankle/hindfoot effusions and mild regional soft-tissue edema."
}