Developmental dysplasia of the hip (DDH) represents a spectrum of disease from dysplasia (shallow acetabulum) → subluxation → dislocation ^[1][2]. The examination varies dramatically with the child's age: neonatal screening relies on provocative tests (Barlow, Ortolani), whereas the older infant and walking child require assessment of abduction restriction, limb length discrepancy (LLD), and gait. This guide covers the full age spectrum but emphasizes the neonatal/infant examination as this is the highest-yield OSCE scenario.

Before touching the child, complete the following — this is worth marks in every OSCE:

After approximately 3 months, the Barlow and Ortolani tests become unreliable because soft tissue contractures form around the dislocated hip ^[1]. The key findings are now:

1. Limited hip abduction — the single most important sign in this age group
2. Galeazzi sign — LLD
3. Asymmetric skin folds — low specificity but should prompt imaging
4. Apparent limb length discrepancy on measurement

• Greater trochanter: Palpate for position (may be displaced superiorly in DDH) and tenderness (trochanteric bursitis — more relevant in adults) ^[4][5]
• Proximal femur: Tenderness may suggest fracture
• Telescoping test (in infants with suspected complete dislocation):
  • With baby supine, hip flexed 90°, push and pull the femur along its long axis
  • Positive: Excessive pistoning movement — the femoral head slides up and down without constraint
  • Pathophysiology: No acetabular containment → axial force moves the head freely

To complete my examination, I would like to ^[4][5][3]:

1. Examine the spine: Rule out spinal dysraphism (midline defects — dimples, tufts of hair, hemangiomas) which can cause neurogenic hip dysplasia ^[3]
2. Examine the knees and feet: Rule out referred pain and associated conditions (talipes equinovarus is associated with DDH) ^[2]
3. Examine the contralateral hip: DDH can be bilateral (20% of cases)
4. Neurovascular assessment of the lower limbs ^[4][5]
5. Request imaging:
   • USG hip: Birth to 4 months (femoral head is cartilaginous, not visible on XR) ^[1][2]
   • XR hip: From 4–6 months onwards (femoral head begins to ossify — can assess Shenton line, acetabular index, femoral head position) ^[1]

These are commonly asked to justify your examination findings in the viva:

• Female sex (increased ligament laxity) ^[1][2]
• Breech presentation ^[1][2]
• Family history of DDH ^[1][2]
• First-born (tighter uterus) ^[1]
• Oligohydramnios ^[1]

• Why Barlow before Ortolani: Logically, you first test whether a located hip can be dislocated (Barlow), then test whether a dislocated hip can be reduced (Ortolani). Some sources say order doesn't matter, but this sequence is more logical.
• Bilateral DDH trap: When both hips are equally affected, asymmetry-based signs are negative (symmetric skin folds, equal knee heights). Must rely on absolute abduction limitation and imaging.
• Imaging choice: USG < 4 months (cartilaginous head); XR > 4–6 months (ossified head) ^[1][2]
• Bryant triangle finding in DDH: Shortened distance above trochanter — this means the greater trochanter is displaced superiorly relative to the ASIS ^[4][5]
• Trendelenburg sign physiology: Not about gluteus medius weakness per se in DDH — it's about the hip being an ineffective fulcrum. The muscle is intact but has no stable pivot point ^[4][5].

"On examination, this is a 6-week-old female neonate who appears comfortable at rest in her mother's arms. She is appropriately grown for age. No orthopedic devices or IV lines are present.

On inspection, I note asymmetric left thigh skin folds with an additional crease on the left side compared to the right. No obvious limb length discrepancy is visible at rest.

On the Galeazzi test with both hips and knees flexed, the left knee sits lower than the right, suggesting left-sided femoral shortening.

On special testing: the Barlow test is positive on the left — I feel a definite clunk as the femoral head dislocates posteriorly with gentle adduction and posterior pressure. The Ortolani test is also positive on the left — the dislocated hip reduces with a palpable clunk on abduction with anterior pressure. Both tests are negative on the right side.

Hip abduction on the left is limited to approximately 50 degrees compared to 75 degrees on the right.

No spinal midline defects are noted. Both feet are in normal position with no features of talipes. Neurovascular examination of both lower limbs is grossly normal.

In summary, the findings are consistent with left-sided developmental dysplasia of the hip — specifically, a dislocatable and reducible left hip, with asymmetric skin folds, a positive Galeazzi sign, and limited left hip abduction. I would like to confirm the diagnosis with an ultrasound of both hips and refer to paediatric orthopaedics for consideration of Pavlik harness treatment. Risk factors to note include female sex and I would clarify birth presentation and family history."

^[1] Senior notes: maxim.md (Section 11.1 Developmental dysplasia of hip) ^[2] Senior notes: Adrian Lui Pediatrics.pdf (p27, p445, p451) ^[3] Senior notes: Adrian Lui Pediatrics.pdf (p8 — Pediatric physical examination tips; p133 — 180° maneuver) ^[4] Senior notes: Ryan Ho Fundamentals.pdf (p139–140 — Hip Joint Examination) ^[5] Senior notes: Ryan Ho Rheumatology.pdf (p18–19 — Hip Joint Examination)