Scoliosis and spinal deformity — formative SAQs

SAQ 1 (10 marks) — The 12-year-old girl with a 32-degree curve and a red flag

Stem: A 12-year-old girl is referred by her school nurse for a spinal curve. She has a LEFT thoracic prominence and complains of intermittent mid-back pain. On examination the Adams forward bend test shows a rib hump, and the abdominal reflexes are asymmetric. The standing radiograph shows a 32-degree left thoracic curve, Risser 0. Outline your assessment, the red-flag screen, the investigation strategy, and the management. ^[2]

Model answer

Assessment and the red-flag screen (3 marks). This is a 12-year-old with a spinal curve, but the features break the pattern of the typical idiopathic curve. The idiopathic curve is painless, right thoracic, and carries a normal neurological examination. This girl has three red flags: a LEFT thoracic curve (idiopathic thoracic curves are overwhelmingly right-sided), back pain (the idiopathic curve is painless), and an asymmetric abdominal reflex (a recognised sign of a syringomyelia). The red-flag screen — onset under 10, a left thoracic curve, pain, a neurological deficit, skin stigmata, and rapid progression — is positive, and the curve is non-idiopathic until proven otherwise. ^[2]

Investigation strategy (3 marks). Because the red-flag screen is positive, the investigation adds a magnetic resonance imaging of the neural axis before any bracing, to exclude a syringomyelia, a Chiari malformation, a tethered cord, and a spinal cord tumour. The standing posteroanterior radiograph has measured the Cobb angle at 32 degrees and staged the maturity at Risser 0 (substantial growth remaining). The asymmetric abdominal reflex and the left thoracic pattern make the magnetic resonance imaging mandatory, and the finding on the imaging redirects the management from the brace to the neurosurgical and the spinal intervention. A renal ultrasound and an echocardiogram are added if the imaging suggests a congenital or a syndromic cause. ^[2]

Management (4 marks). The management follows the imaging. If the magnetic resonance imaging reveals a syringomyelia or a Chiari malformation, the child is referred to the neurosurgical team for the management of the neural-axis lesion, and the bracing and the elective fusion wait until the cord is secured. If the imaging is normal, the curve is re-classified as idiopathic and placed on the ladder by the two numbers — the 32-degree magnitude and the Risser 0 maturity — which would indicate bracing (25 to 40 degrees while growing). The family is counselled on the diagnosis, the natural history, the treatment options, and the safety-net, and the follow-up is arranged. The key teaching point is that the red flag is examined and the imaging obtained before the brace is fitted. ^{[2] [9]}