📋 MOCK OSCE · FCPS, MCPS, MD PAEDIATRICS ⏱ 10 min · TALL STATURE

Tall Stature · Short Case

Candidate task: perform focused examination on a child with tall stature, discuss differential diagnosis, investigations, management & follow‑up.
Pre‑exam Protocol
⏤ · Wash, Warm, Introduce, Position, Expose, Approach ▾

Standard pre‑examination protocol – must be demonstrated:

🖐 Wash hands with sterilizing solution.
🔥 Warm hands and stethoscope.
👋 Introduce yourself to child & parent.
🧍 Position child: standing for initial inspection, then sitting, then lying (as needed).
👕 Exposure — chest and limbs fully exposed, warm environment.
➡️ Approach from the right side.
✔ CPSP marker: Pre‑exam Protocol is observed and scored.
1. Clinical Examination (≈6 min)
02 General Look (Inspection from end of bed) ▾

Key observations:

  • Body habitus: Marfanoid (dolichostenomelia), eunuchoid (long limbs).
  • Dysmorphic features: Sotos (frontal bossing, large hands), Beckwith‑Wiedemann (macroglossia, ear creases), Klinefelter (tall, thin, gynecomastia).
  • Nutritional status: obesity (exogenous, Klinefelter), thin (Marfan).
  • Tanner staging: precocious (early growth spurt → tall), delayed (eunuchoid).
  • Skin: café‑au‑lait spots (NF‑1), hyperpigmented areas (McCune‑Albright).
  • Activity & intellect: developmental delay (Sotos, Beckwith‑Wiedemann), behavioral issues (Klinefelter).
👁 Red flags: arachnodactyly + lens dislocation + aortic dilation → Marfan syndrome.
03 Measurements & Body Proportions ▾

Anthropometry:

  • Height: plot on growth chart; calculate height velocity.
  • Upper segment / Lower segment (US:LS) ratio: normal ~1.7 at birth → ~0.9 at 18 years. Decreased (long legs) → Marfan, Klinefelter; Increased (short trunk) → skeletal dysplasia.
  • Arm span: normally < height before 8 years, > height after puberty. Arm span > height by >5 cm → Marfan, eunuchoid.
  • Head circumference: macrocephaly (Sotos, Beckwith‑Wiedemann).
  • Weight: BMI; obesity (exogenous, Klinefelter).
📏 Key: low US:LS + arm span > height + arachnodactyly → Marfan / homocystinuria.
04 Manoeuvres (Marfan & other clues) ▾

Systematic manoeuvres:

  • Hands & feet together: asymmetry (hemihypertrophy → Beckwith‑Wiedemann), genu valgum (homocystinuria), genu recurvatum (Marfan).
  • Bend forward, touch toes: scoliosis (Marfan, Sotos, homocystinuria), kyphosis (pituitary gigantism).
  • Beighton score (hypermobility): thumb to forearm, passive hyperextension of 5th finger >90°, elbows >10° hyperextension, knees >10° hyperextension, palms flat on floor. Score ≥5/9 → Marfan.
  • Arachnodactyly: Steinberg sign (thumb extends beyond ulnar border), Walker‑Murdoch sign (thumb overlaps 5th finger when encircling wrist).
  • Tremor: arms outstretched → hyperthyroidism.
📌 Examiner expectation: perform these manoeuvres and explain their significance.
05 General Physical Exam (Hands → Face → Chest → Limbs) ▾

Systematic examination:

  • Hands: arachnodactyly, large hands (Sotos, pituitary gigantism), nails (clubbing – CF, CHD).
  • Face: myopia (Marfan), lens dislocation (up – Marfan; down – homocystinuria), exophthalmos (hyperthyroidism), frontal bossing (Sotos, Beckwith‑Wiedemann).
  • Chest: pectus carinatum/excavatum (Marfan, homocystinuria), gynecomastia (Klinefelter).
  • Cardiovascular: pulse pressure (aortic regurgitation – Marfan), BP (hypertension – NF‑1, Cushing).
  • Abdomen: hepatomegaly (homocystinuria, Beckwith‑Wiedemann), organomegaly (Beckwith‑Wiedemann → Wilms tumour screening).
  • Genitalia: Tanner staging (precocious/delayed), testicular volume (Klinefelter).
  • Lower limbs: large feet (Sotos, pituitary gigantism), pes planus (Marfan).
🔍 Key associations: tall + arachnodactyly + lens dislocation + aortic root dilation → Marfan. Tall + intellectual disability + macrocephaly → Sotos.
06 Developmental Assessment & Associated Signs ▾

Assess:

  • Motor milestones: may be delayed (Sotos, Beckwith‑Wiedemann).
  • Language: delayed (Klinefelter, Sotos).
  • Intellectual disability: Sotos, Beckwith‑Wiedemann, homocystinuria (untreated).
  • Behaviour: social difficulties (Klinefelter), hyperactivity (Sotos).
  • Hearing: sensorineural deafness (homocystinuria).
  • Vision: myopia (Marfan), lens dislocation (Marfan, homocystinuria).
🧠 Genetic clues: tall + intellectual disability + macrocephaly → Sotos (NSD1 mutation). Tall + learning difficulties + gynecomastia → Klinefelter (47,XXY).

📋 Case Presentation – (fill in during exam)

This is a _____-year-old _____ child, referred for _____ (tall stature / overgrowth / family concern). On examination, the child appears _____ (well/unwell/lethargic), with _____ (body habitus / dysmorphic features). Measurements: height _____ percentile, US:LS ratio _____, arm span _____ cm, head circumference _____ percentile. Manoeuvres: arachnodactyly _____ (present/absent), hypermobility _____. General exam: _____ (hands, face, chest, CVS, abdomen, genitalia). Developmental: _____ (delayed/appropriate). Associated signs: _____.

2. Viva Discussion (≈4 min)
07 Viva · Differential, Investigations, Management, Follow‑up ▾
🔹 Differential Diagnosis

• Constitutional (familial) tall stature – normal variant
• Marfan syndrome – arachnodactyly, lens dislocation, aortic root dilation
• Homocystinuria – Marfanoid habitus + intellectual disability + thromboembolism
• Sotos syndrome – macrocephaly, learning disability, distinctive facies
• Beckwith‑Wiedemann syndrome – macrosomia, macroglossia, omphalocele, tumour risk
• Klinefelter syndrome – tall, thin, gynecomastia, small testes, learning difficulties
• XYY syndrome – tall, behavioural problems, severe acne
• Pituitary gigantism – excessive GH, large hands/feet, coarsening facies
• McCune‑Albright syndrome – fibrous dysplasia, café‑au‑lait spots, precocious puberty
• Hyperthyroidism – tremor, tachycardia, goitre
• Obesity (exogenous) – tall in childhood, but normal adult height

🔹 Investigations – Diagnosis

• Bone age – advanced (pituitary gigantism, precocious puberty), normal (constitutional, Marfan).
• GH / IGF‑1 – elevated (pituitary gigantism).
• Thyroid function – hyperthyroidism.
• Echocardiography – aortic root diameter (Marfan).
• Skeletal survey – fibrous dysplasia (McCune‑Albright), scoliosis.

🔹 Investigations – Aetiology

• Genetic: FISH for 7q11.23 (Williams), FBN1 (Marfan), NSD1 (Sotos), karyotype (Klinefelter, XYY).
• Metabolic: plasma homocysteine (homocystinuria).
• Endocrine: IGF‑1, GH suppression test (gigantism).

🔹 Investigations – Exclude Others

• Echocardiography – exclude aortic dilation / dissection (Marfan).
• Ophthalmology – lens dislocation (Marfan, homocystinuria).
• Abdominal ultrasound – Wilms tumour (Beckwith‑Wiedemann).

🔹 Investigations – Rule Out Complications

• Echocardiography – aortic regurgitation, mitral valve prolapse (Marfan).
• CT/MRI brain – pituitary adenoma (gigantism).
• ABG – if metabolic acidosis (homocystinuria – rarely).
• Tumour markers – AFP (hepatoblastoma in Beckwith‑Wiedemann).

🔹 Management – Across Organ Systems

Endocrine

GH suppression (octreotide/pegvisomant) for gigantism; thyroid replacement if hypothyroid.

Cardiovascular

β‑blockers (Marfan – aortic root dilation); regular echocardiographic surveillance.

Ophthalmology

Lens extraction (Marfan/homocystinuria); regular eye exams.

Musculoskeletal

Physiotherapy, orthopaedic referral (scoliosis, pectus).

Neurology

Seizure management (Sotos, Beckwith‑Wiedemann).

Developmental

Early intervention, educational support, speech therapy.

Tumour Surveillance

Abdominal US and AFP (Beckwith‑Wiedemann – Wilms, hepatoblastoma).

Genetic Counselling

Recurrence risk (autosomal dominant, X‑linked, or de novo).

📈 Prognosis

  • Constitutional tall: excellent; reassure.
  • Marfan: life‑long risk of aortic dissection; monitor aortic root.
  • Homocystinuria: treat with B6, folate, B12 to reduce thromboembolic risk.
  • Sotos: good life expectancy; developmental outcomes vary.
  • Beckwith‑Wiedemann: tumour risk highest in first 7 years; surveillance reduces mortality.
  • Pituitary gigantism: good if early treatment; risk of diabetes, hypertension.

📋 Follow‑up Schedule

  • Constitutional: monitor height velocity annually.
  • Marfan: cardiology 6‑12 monthly, ophthalmology annually, orthopaedics annually.
  • Beckwith‑Wiedemann: AFP & abdominal US every 3‑6 mo until age 7; then annually.
  • Sotos: developmental paediatrics, neurology, orthopaedics annually.
  • Pituitary gigantism: endocrinology 3‑6 monthly; MRI surveillance.
  • Transition: lifelong follow‑up to adult services.
💡 Examiner expectation: logical differential (constitutional vs syndromic vs endocrine), systematic investigation (diagnosis → aetiology → exclude others → complications), and management tailored to the underlying condition. Know the key features of Marfan, Sotos, Beckwith‑Wiedemann, Klinefelter, and homocystinuria.
📚 Visit paeds.online for more CPSP resources
Mock OSCE · Tall Stature · Based on Wyne‑Harris, Nelson & Pediatric Clinical Advisor