A 2-day-old neonate born to a 28-year-old primigravida presents with bilateral inversion and plantarflexion of the feet. Clinical examination confirms the diagnosis of congenital talipes equinovarus. Which investigation is most appropriate to assess the severity and guide treatment planning?

## Investigation of Choice in Neonatal CTEV ### Clinical Context In a newborn with suspected CTEV, imaging is essential to: - Confirm the diagnosis - Assess severity (Pirani score, Dimeglio classification) - Identify associated skeletal abnormalities - Guide conservative vs. surgical management ### Why Plain Radiography is the Gold Standard **Key Point:** Plain radiographs (AP, lateral, and sometimes axial views) are the first-line and most cost-effective imaging modality in CTEV. **High-Yield:** Plain films allow measurement of critical angles: - Talocalcaneal angle (TCA) — normally >25° in AP view; reduced in CTEV - Talonavicular angle — assesses forefoot adduction - Tibiocalcaneal angle — assesses equinus severity ### Role of Other Investigations | Investigation | Indication | Timing | |---|---|---| | **Plain radiograph** | Initial diagnosis, severity grading, treatment planning | Day 1–2 of life | | **Ultrasound** | Soft tissue assessment, early detection in high-risk families | Prenatal or neonatal | | **MRI** | Complex/resistant cases, associated CNS anomalies, pre-operative planning | After failed conservative therapy | | **CT scan** | Rarely needed; reserved for complex anatomy before surgical intervention | Late/surgical cases | **Clinical Pearl:** In the neonatal period, plain radiographs are sufficient because the foot is largely cartilaginous; ossification is incomplete, but the bony landmarks (talus, calcaneus, navicular) are visible enough for angle measurement. **Tip:** The Pirani score (clinical) and Dimeglio score (radiographic + clinical) are used to grade severity and predict response to conservative (Ponseti) treatment. [cite:Tuli's Orthopedics 6e Ch 18]