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What is Absence of sesamoid bone in girl of age about normal range of puberty is said to have: and explain in detail?
PHV-Peak height velocity occurs approximately at 12 years in girls and 14 years in boys and ossification of ulnar sesamoid of hand occurs roughly 6 months before the PHV. 
Key Concept: 
The absence or delayed presence of sesamoid bone is due to delay in reaching puberty.