This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pediatric orthopedics, Subject name: Orthopaedics
Oolani&;s test is used in 
Select and explain. 
A. congenital dislocation of knee, B. Obstetric brachial plexus injury, C. Developmental dysplasia of hip, D. Tom Smith's ahritis
C: Developmental dysplasia of hip
Answer: C: Developmental dysplasia of hip 
Explanation: OOLANI&;STEST is used to test DDH in infants In this test the baby&;s thighs are held with the thumbs medially and the fingers resting on the greater trochanters; the hips are flexed to 90 degrees and gently abducted. In NORMAL baby, there is smooth abduction to almost 90 degrees. In CONGENITAL DISLOCATION the movement is usually impeded,but if pressue is applied to the greater trochantehere is a soft &;CLUNK&; as the dislocation reduces,and then the hip abducts fully(JERK OF ENTRY) If abduction stops halfway and there is no jerk of entry, there may be an irreducible dislocation. ref:APLEY&;S 9th edition page no.499