OR12.1 | Congenital Lesions — Glossary

A radiographic measure of acetabular depth on an AP pelvis radiograph, defined as the angle between Hilgenreiner's line and a line from the triradiate cartilage to the lateral bony acetabular rim; normal values decrease with age (approximately <30° at birth, <20° by 2 years); elevation indicates acetabular dysplasia.

A screening test for scoliosis in which the patient bends forward at the waist with knees straight and arms hanging; a rib hump or paraspinal asymmetry on one side indicates rotational scoliosis, which can be quantified with a scoliometer.

A hindbrain anomaly consistently associated with myelomeningocele, characterised by downward displacement of the cerebellar tonsils, vermis, and brainstem through the foramen magnum; associated with hydrocephalus (requiring VP shunting) and can cause cranial nerve dysfunction and apnoeic episodes.

A provocation manoeuvre for neonatal DDH: posterior pressure with the thumb while adducting the hip attempts to push the femoral head posteriorly out of the acetabulum; a positive Barlow (palpable clunk of dislocation) indicates an unstable but locatable hip.

The mnemonic for the four anatomical components of clubfoot (CTEV): Cavus (high medial arch), Adductus (forefoot medial deviation), Varus (hindfoot inversion), Equinus (plantarflexion of the entire foot); the Ponseti method corrects them in this reverse order (C first, E last).

The standard measurement of scoliotic curve magnitude: the angle formed between perpendiculars to the end-plate of the most tilted upper end vertebra and the most tilted lower end vertebra of the curve on a standing AP radiograph.

A congenital postural deformity of the neck caused by fibrosis of the sternocleidomastoid muscle, manifesting as head tilt toward the affected side and chin rotation to the contralateral side; associated with a palpable fibrotic mass in the SCM in the neonatal period.

A congenital foot deformity characterised by four components — Cavus, Adductus, Varus, and Equinus (CAVE) — reflecting integrated malalignment of the foot skeleton with the talus plantarflexed and internally rotated within the ankle mortise; one of the most common congenital musculoskeletal anomalies.

A spectrum of abnormal hip development ranging from acetabular dysplasia through subluxation to complete dislocation, reflecting failure of normal concentric femoral head–acetabulum articulation during the perinatal period; formerly called congenital dislocation of the hip.

A clinical sign of DDH in infants aged 3–6 months and beyond: with both hips and knees flexed to 90° and feet flat, apparent shortening of one femur (lower knee on the affected side) indicates ipsilateral hip dislocation; also called Allis' sign.

The standard ultrasound classification system for neonatal hip dysplasia, based on two angles: the alpha angle (bony acetabular roof depth, normal ≥60°) and the beta angle (cartilaginous roof); Grade I is normal, Grade IIa is physiologically immature, Grades IIb and above indicate progressive dysplasia.

A horizontal reference line drawn through both triradiate cartilages on an AP pelvis radiograph, used as the baseline for measuring the acetabular index and the vertical height of the femoral head; one of three reference lines used to assess DDH on plain X-ray.

The most severe form of spina bifida cystica, in which meninges, CSF, and neural tissue herniate through the posterior vertebral defect; associated with lower-limb paralysis, neurogenic bladder, Arnold-Chiari II malformation, and hydrocephalus in the majority of cases.

A reduction manoeuvre for neonatal DDH: with the hip flexed to 90°, abduction combined with anterior lifting of the greater trochanter produces a palpable clunk as the dislocated femoral head reduces into the acetabulum; positive Ortolani indicates a dislocatable (reducible) hip.

A dynamic fabric splint used for DDH in infants up to 6 months of age; holds the hip in flexion (~100°) and abduction without rigid immobilisation, allowing active kicking movement that mechanically stimulates acetabular remodelling around the reduced femoral head.

A minor surgical procedure forming the final step of the Ponseti casting series for CTEV, in which the tendo Achillis is divided subcutaneously under local anaesthesia to correct residual equinus deformity; required in approximately 80% of idiopathic clubfeet; followed by a final cast for 3 weeks.

A six-parameter clinical scoring system for CTEV severity (0–6), assessing equinus, empty heel, posterior crease, curvature of the lateral border, medial crease, and talar head coverage; guides the expected number of Ponseti casting cycles required.

Asymmetric flattening of the skull, commonly developing secondary to untreated congenital muscular torticollis as the infant preferentially rests on one occiput; also occurs in positional plagiocephaly without torticollis.

The gold standard conservative treatment for idiopathic CTEV, comprising sequential weekly manipulation and above-knee casting to correct the CAVE deformity in order (Cavus → Adductus + Varus → Equinus), followed by percutaneous Achilles tenotomy and a 4–5 year foot abduction brace protocol; success rates exceed 90% for idiopathic cases.

A radiographic measure of skeletal maturity based on the degree of ossification of the iliac crest apophysis, graded 0–5; Risser 5 indicates complete fusion and near-complete cessation of spinal growth, signalling reduced risk of curve progression.

A lateral curvature of the spine measuring ≥10° by the Cobb angle on a standing AP radiograph, almost always with vertebral rotation; classified as idiopathic (most common), congenital (vertebral anomaly), or neuromuscular (secondary to underlying neurological or muscular disease).

A form of spinal dysraphism in which the posterior vertebral arch fails to fuse but meninges and neural tissue remain within the spinal canal; covered by intact skin, usually asymptomatic, but may be associated with a tethered spinal cord if cutaneous stigmata are present.