## FINDINGS

### Bones / Alignment
No acute fracture, stress fracture, dislocation, destructive marrow lesion, or avascular necrosis identified. Tibiotalar alignment is preserved.

There are irregular marginal osteophytes/spurring about the tibiotalar joint, greatest anteriorly at the anterior distal tibial plafond and opposing dorsal talar neck/anterior talar dome, with additional chronic osseous irregularity/spurring in the medial and lateral gutters. Prominent posterior talar process/os trigonum region morphology is present, without convincing associated marrow edema on the provided fluid-sensitive images.

### Tibiotalar Joint / Cartilage
Small-to-moderate tibiotalar joint effusion, most conspicuous in the anterior recess and gutters. Mild synovitis and capsular/gutter scarring are suggested, particularly anteriorly and anterolaterally.

Mild post-traumatic/degenerative tibiotalar chondral and articular surface irregularity is present, greatest anteriorly and in the gutter regions.

Focal medial-to-central talar dome/shoulder articular surface and subchondral irregularity/low T1 signal is suspicious for a chronic osteochondral/chondral-subchondral lesion. No displaced osteochondral fragment or convincing acute marrow edema is identified.

### Subtalar Joint / Sinus Tarsi
Small posterior subtalar joint effusion/recess fluid.

Prominent fluid/edema within the sinus tarsi/anterior subtalar region with effacement of the expected sinus tarsi fat and a small lobulated fluid-like component, compatible with sinus tarsi synovitis/ganglion-type fluid. The cervical/interosseous talocalcaneal ligament region is obscured by fluid/edema, with suspected chronic sprain/degeneration of the sinus tarsi ligament complex.

### Ligaments
The anterior talofibular ligament is attenuated/poorly defined and replaced by scar-like tissue in the anterolateral gutter, compatible with chronic ATFL tear/insufficiency.

The calcaneofibular ligament region is mildly indistinct/thickened with adjacent fluid signal, suspicious for chronic sprain/partial tearing. No retracted complete CFL tear is evident.

Deltoid ligament complex and syndesmotic ligaments are grossly intact without definite acute disruption or mortise widening. Posterior talofibular ligament is grossly intact.

### Tendons
Mild fluid around the peroneal tendons at and just below the lateral malleolus, compatible with mild peroneal tenosynovitis. No definite peroneal tendon split tear or rupture.

Prominent fluid tracking along the flexor hallucis longus tendon sheath posterior-medially and beneath the sustentaculum tali, compatible with FHL tenosynovitis and/or communicating ganglion-like fluid.

Achilles tendon, posterior tibial tendon, flexor digitorum longus tendon, and anterior extensor tendons are grossly intact.

### Plantar Fascia / Soft Tissues
No convincing plantar fasciitis or plantar fascial tear. Mild nonspecific periarticular soft tissue edema, greatest near the sinus tarsi/lateral hindfoot. No discrete soft tissue mass or focal fluid collection.

## IMPRESSION

1. **Chronic post-traumatic tibiotalar arthropathy/impingement morphology** with residual or recurrent anterior distal tibial and dorsal talar neck osteophytes, anterior capsular scarring, and medial/lateral gutter spurring. Small-to-moderate tibiotalar effusion with mild synovitis/scarring. **Confidence: High.**

2. **Chronic lateral ligament injury**, including chronic ATFL tear/attenuation with anterolateral gutter scar tissue; suspected chronic CFL sprain/partial tear. Findings may contribute to anterolateral ankle impingement symptoms. **Confidence: Medium-high for ATFL; medium-low for CFL.**

3. **Prominent sinus tarsi fluid/edema with small lobulated ganglion/synovitis-type component and small subtalar effusion**, compatible with sinus tarsi syndrome in the appropriate clinical setting. Suspected chronic degeneration/sprain of the sinus tarsi ligament complex. **Confidence: High for sinus tarsi fluid/synovitis; Medium for ligament degeneration.**

4. **Suspected chronic medial-to-central talar dome osteochondral/chondral-subchondral lesion**, without displaced fragment or convincing acute marrow edema. **Confidence: Medium.**

5. **FHL tenosynovitis and/or communicating ganglion-like fluid**, and mild peroneal tenosynovitis. No definite tendon tear. **Confidence: Medium-high for FHL; Medium for peroneals.**

6. Prominent posterior talar process/os trigonum region morphology with posterior recess low-signal tissue/fluid, which can be seen with posterior ankle impingement if clinically concordant. **Confidence: Medium.**

7. No acute osseous abnormality. **Confidence: High.**