AIM LEARNING CYCLE | FINAL YEAR MBBS | NEUROSCIENCE
KMU Past Paper Practice
Topic 11. Congenital Spinal Malformations, Vertebral Disorders & Kyphoscoliosis
20 A-Type Single Best Answer MCQs | Clinical Reasoning & Integrated Application
Original KMU-style practice questions; not verified historical past-paper questions.
MCQ 1
Question:
A 26-year-old pregnant woman undergoes second-trimester antenatal screening. Maternal serum alpha-fetoprotein is markedly elevated. Subsequent fetal ultrasonography demonstrates an open defect involving the lumbosacral region. Which mechanism best explains the elevated maternal serum marker?
Options:
- Increased maternal hepatic synthesis of alpha-fetoprotein
- Increased fetal renal excretion caused by urinary obstruction
- Reduced placental clearance of maternal serum proteins
- Leakage of fetal alpha-fetoprotein through an open neural defect
- Increased maternal production of neural tube proteins
MCQ 2
Question:
At 22 weeks of gestation, fetal ultrasonography demonstrates a lumbosacral spinal defect accompanied by abnormal curvature of the cerebellum and a concave appearance of the frontal skull bones. The obstetrician suspects an open spinal neural tube defect. Which associated condition best explains these intracranial findings?
Options:
- Chiari II malformation
- Dandy-Walker malformation
- Isolated cerebral ventriculomegaly
- Agenesis of the corpus callosum
- Congenital arachnoid cyst
MCQ 3
Question:
A newborn with an open lumbosacral neural tube defect develops fever, irritability and poor feeding before definitive surgical closure. Examination reveals inflammation and discharge around the exposed neural tissue. Which complication should be considered most urgently?
Options:
- Progressive spinal scoliosis
- Congenital vertebral instability
- Mechanical lumbar radiculopathy
- Postural spinal deformity
- Meningitis with systemic infection
MCQ 4
Question:
A 4-month-old infant with repaired myelomeningocele has a ventriculoperitoneal shunt. The mother reports repeated vomiting, irritability and poor feeding over two days. Examination reveals a tense anterior fontanelle. What is the most appropriate immediate clinical concern?
Options:
- Normal postoperative adjustment
- Possible shunt malfunction with raised intracranial pressure
- Isolated gastroesophageal reflux
- Developmental delay without acute complications
- Uncomplicated positional plagiocephaly
MCQ 5
Question:
A newborn with a high lumbar myelomeningocele has severe weakness of both lower limbs, while another newborn with a low sacral lesion retains substantial leg movement. Which anatomical principle best explains the difference in neurological disability?
Options:
- The extent of skin involvement determines muscle power
- The size of the meningeal sac determines all neurological deficits
- Higher neurological lesion levels affect more lower limb motor segments
- Sacral lesions produce greater motor loss than lumbar lesions
- Motor impairment depends exclusively on the infant’s birth weight
MCQ 6
Question:
An 8-year-old child with repaired myelomeningocele experiences chronic constipation and occasional fecal incontinence. The family reports embarrassment and difficulty maintaining school attendance. Which long-term management strategy best addresses the underlying functional problem?
Options:
- Restrict daily food intake to reduce stool formation
- Treat every episode as an acute gastrointestinal infection
- Delay bowel training until the child reaches adulthood
- Establish an individualized structured bowel management programme
- Avoid physical activity to prevent episodes of incontinence
MCQ 7
Question:
A 5-year-old child with a congenital lumbar spinal malformation has weak ankle dorsiflexion and difficulty maintaining a stable walking posture. The orthopedic team recommends ankle-foot orthoses and physiotherapy. What is the main functional objective?
Options:
- Restore normal spinal cord tissue anatomically
- Improve alignment, mobility and prevention of contractures
- Eliminate the need for neurological follow-up
- Reverse the original embryological neural tube defect
- Permanently recover absent peripheral sensation
MCQ 8
Question:
A newborn with myelomeningocele develops episodes of stridor, difficulty swallowing and brief periods of apnea. The treating team suspects brainstem dysfunction from an associated hindbrain abnormality. Which anatomical change most plausibly explains these findings?
Options:
- Degeneration of the lumbar intervertebral discs
- Compression of the peripheral sciatic nerve
- Displacement of the cerebellum into the cerebral hemispheres
- Inflammation restricted to the sacral nerve roots
- Downward displacement of hindbrain structures through the foramen magnum
MCQ 9
Question:
A 19-year-old male athlete presents with localized lower back pain that worsens during lumbar extension and improves with rest. Imaging demonstrates a defect through the pars interarticularis without displacement of the vertebral body. Which diagnosis best describes the radiological abnormality?
Options:
- Degenerative spondylolisthesis
- Lumbar spinal stenosis
- Spondylolysis
- Vertebral osteomyelitis
- Lumbar disc extrusion
MCQ 10
Question:
A 16-year-old boy presents with persistent lumbar pain. Lateral spinal radiography shows that the fifth lumbar vertebral body has moved anteriorly relative to the first sacral vertebra. There is no history of acute major trauma. Which structural disorder best explains this finding?
Options:
- Posterior vertebral arch non-fusion
- Isolated lumbar disc degeneration
- Thoracolumbar compression fracture
- Spondylolisthesis
- Congenital thoracic kyphosis
MCQ 11
Question:
A 44-year-old man has several months of lower back pain, evening fever and reduced appetite. Spinal imaging demonstrates destruction of adjacent vertebral endplates, disc-space narrowing and a paravertebral collection. Tuberculous infection is suspected. Which pathological process best explains the vertebral deformity?
Options:
- Infective destruction and collapse of vertebral bodies
- Congenital failure of posterior arch fusion
- Isolated degeneration of paraspinal muscles
- Excessive growth of normal vertebral cartilage
- Primary shortening of the spinal nerve roots
MCQ 12
Question:
A 50-year-old patient has radiologically confirmed lumbar disc degeneration. MRI shows loss of normal disc height and reduced signal intensity within the nucleus pulposus. Which underlying change most directly contributes to these findings?
Options:
- Increased water retention within the disc matrix
- Hypertrophy of the spinal cord gray matter
- Increased synovial fluid production inside the disc
- Congenital separation of the vertebral arches
- Loss of proteoglycans and reduced water content of the disc
MCQ 13
Question:
A 42-year-old man develops pain radiating from the lower back into the lateral leg and dorsum of the foot. Examination reveals weakness of great toe extension and reduced sensation over the first dorsal web space. Which nerve root is most likely affected?
Options:
- L2 nerve root
- L5 nerve root
- S2 nerve root
- L3 nerve root
- S3 nerve root
MCQ 14
Question:
A 47-year-old woman presents with pain extending from the lumbar region to the posterior calf and lateral border of the foot. Examination reveals reduced ankle plantar flexion and an absent ipsilateral ankle jerk. Which neurological localization best explains the findings?
Options:
- L2 nerve root involvement
- L3 nerve root involvement
- L4 nerve root involvement
- S1 nerve root involvement
- C8 nerve root involvement
MCQ 15
Question:
A 59-year-old woman presents with neck pain radiating into her right thumb and index finger. Examination reveals reduced biceps reflex and mild weakness of elbow flexion, without gait disturbance or increased lower limb reflexes. Which diagnosis best explains the findings?
Options:
- Cervical spinal cord myelopathy
- Thoracic spinal cord compression
- C6 cervical radiculopathy
- Lumbar nerve root compression
- Isolated cervical muscle strain
MCQ 16
Question:
A 13-year-old girl is referred for apparent scoliosis. Examination reveals pelvic tilt caused by a leg-length discrepancy. When the discrepancy is corrected with a suitable block under the shorter limb, the apparent spinal curvature resolves. Which conclusion is most appropriate?
Options:
- The curvature represents a flexible functional deformity
- The curvature results from congenital vertebral fusion
- The patient has progressive idiopathic structural scoliosis
- The deformity indicates an established rotational vertebral abnormality
- The curvature is caused by thoracic vertebral collapse
MCQ 17
Question:
A 15-year-old boy has increasing rounding of his upper back. The deformity remains prominent when he attempts to stand straight. Lateral spinal radiographs reveal anterior wedging of several adjacent thoracic vertebrae with irregular vertebral endplates. Which diagnosis is most likely?
Options:
- Flexible postural kyphosis
- Congenital lumbosacral meningocele
- Lumbar degenerative spondylolisthesis
- Idiopathic lumbar lordosis
- Scheuermann kyphosis
MCQ 18
Question:
A 72-year-old woman with longstanding osteoporosis develops progressively increasing thoracic curvature. Spinal radiography demonstrates multiple anteriorly wedged vertebral bodies. Which mechanism best explains the progressive deformity?
Options:
- Increased intervertebral disc hydration
- Reduced bone strength causing anterior vertebral collapse
- Congenital incomplete posterior arch fusion
- Primary hypertrophy of lumbar nerve roots
- Increased elasticity of thoracic spinal ligaments
MCQ 19
Question:
A 17-year-old patient with severe kyphoscoliosis develops increasing breathlessness on exertion. Pulmonary function testing shows reduced forced vital capacity and reduced total lung capacity, with a relatively preserved FEV1/FVC ratio. Which mechanism best explains this pattern?
Options:
- Increased airway mucus secretion producing obstruction
- Primary destruction of alveolar septal walls
- Reversible narrowing of peripheral bronchioles
- Reduced chest wall expansion causing restrictive physiology
- Increased lung compliance from reduced elastic recoil
MCQ 20
Question:
A 12-year-old child with congenital angular kyphosis is brought for follow-up. The parents report increasing difficulty climbing stairs and frequent falls. Examination reveals bilateral lower limb spasticity and exaggerated tendon reflexes. Which management decision is most appropriate?
Options:
- Continue routine observation until skeletal maturity
- Begin prolonged bed rest without imaging
- Arrange urgent evaluation for spinal cord compression
- Treat solely with analgesics and reassurance
- Delay specialist referral until respiratory symptoms appear