Editing Bone age (section)

{{Short description|Degree of a person's skeletal development}}
[[File:X-ray of hand, where bone age is automatically found by BoneXpert software.jpg|thumb|[[Projectional radiography|X-ray]] of a left hand, with automatic calculation of bone age by a computer software]]
'''Bone age''' is the degree of a person's [[bone|skeletal]] development. In children, bone age serves as a measure of physiological maturity and aids in the diagnosis of growth abnormalities, endocrine disorders, and other medical conditions.<ref name=":0">{{Cite book |url=https://www.worldcat.org/oclc/1075522289 |title=Greenspan's basic & clinical endocrinology |date=2018 |editor-first1=David G. |editor-last1=Gardner |editor-first2=Dolores M. |editor-last2=Shoback |editor-first3=Francis S. |editor-last3=Greenspan |isbn=9781259589287 |edition=10th |location=New York, N.Y. |publisher=[[McGraw Hill Education|McGraw-Hill Education LLC.]] |oclc=1075522289}}</ref><ref name=":1">{{Cite book |url=https://www.worldcat.org/oclc/1131863622 |title=Williams textbook of endocrinology |date=2020 |editor-first1=Shlomo |editor-last1=Melmed |editor-first2=Richard J. |editor-last2=Auchus |editor-first3=Allison B. |editor-last3=Goldfine |editor-first4=Ronald |editor-last4=Koenig |editor-first5=Clifford J. |editor-last5=Rosen |first=Robert Hardin |last=Williams |isbn=978-0-323-71154-8 |edition=14th |publisher=[[Elsevier]] |location=Philadelphia, PA |oclc=1131863622}}</ref><ref name=":6">{{Cite book |url=https://www.worldcat.org/oclc/746747102 |title=Skeletal development of the hand and wrist: a radiographic atlas and digital bone age companion |date=2011 |publisher=[[Oxford University Press, USA]] |first=Cree M. |last=Gaskin |isbn=978-0-19-978213-0 |location=Oxford |oclc=746747102}}</ref> As a person grows from [[Fetus|fetal]] life through childhood, [[puberty]], and finishes growth as a young adult, the bones of the [[skeleton]] change in size and shape. These changes can be seen by [[x-ray]] and other imaging techniques. A comparison between the appearance of a patient's bones to a standard set of bone images known to be representative of the average bone shape and size for a given age can be used to assign a "bone age" to the patient.

Bone age is distinct from an individual's biological or chronological age, which is the amount of time that has elapsed since [[childbirth|birth]]. Discrepancies between bone age and biological age can be seen in people with stunted growth, where bone age may be less than biological age. Similarly, a bone age that is older than a person's chronological age may be detected in a child growing faster than normal. A delay or advance in bone age is most commonly associated with normal variability in growth, but significant deviations between bone age and biological age may indicate an underlying medical condition that requires treatment. A child's current height and bone age can be used to predict adult height.<ref name=":2">{{Cite book |url=https://www.worldcat.org/oclc/905229554 |title=Endocrinology: adult & pediatric |date=2016 |editor-first1=J. Larry |editor-last1=Jameson |editor-first2=Leslie J. |editor-last2=DeGroot |editor-first3=D. M. |editor-last3=De Kretser |editor-first4=Linda |editor-last4=Giudice |editor-link4=Linda Giudice |editor-first5=Ashley |editor-last5=Grossman |editor-first6=Shlomo |editor-last6=Melmed  |editor-first7=John T. |editor-last7=Potts |editor-first8=Gordon C. |editor-last8=Weir |publisher=[[Elsevier]]/[[Saunders (imprint)|Saunders]]|isbn=978-0-323-18907-1 |edition=7th |location=Philadelphia, PA |oclc=905229554}}</ref> Other uses of bone age measurements include assisting in the diagnosis of medical conditions affecting children, such as [[constitutional growth delay]], [[precocious puberty]], [[thyroid disease|thyroid dysfunction]], [[growth hormone deficiency]], and other causes of abnormally short or tall stature.

In the United States, the most common technique for estimating a person's bone age is to compare an x-ray of the patient's left hand and wrist to a reference atlas containing x-ray images of the left hands of children considered to be representative of how the skeletal structure of the hand appears for the average person at a given age.<ref name=":1" /> A [[paediatric radiology|paediatric radiologist]] specially trained in estimating bone age assesses the patient's x-ray for growth, shape, size, and other bone features. The image in the reference atlas that most closely resembles the patient's x-ray is then used to assign a bone age to the patient.<ref name=":4">{{Cite book |last=Gilsanz |first=Vicente |url=https://www.worldcat.org/oclc/262680615 |title=Hand bone age: a digital atlas of skeletal maturity |date=2005 |publisher=Springer |others=Osman Ratib |isbn=978-3-540-27070-6 |location=Berlin |oclc=262680615}}</ref> Other techniques for estimating bone age exist, including x-ray comparisons of the bones of the knee or elbow to a reference atlas and [[magnetic resonance imaging]] approaches.<ref name=":0" /><ref>{{Cite book |last=Tomei |first=Ernesto |url=https://www.worldcat.org/oclc/865333229 |title=Text-Atlas of Skeletal Age Determination: MRI of the Hand and Wrist in Children. |date=2013 |publisher=Wiley |others=Richard C. Semelka, Daniel Nissman |isbn=978-1-118-69214-1 |location=Hoboken |oclc=865333229}}</ref>