कशेरुक दण्ड

thumb|250px|kasheruk dand
Back Bone (aangrezi:Back Bone) kasheruk dand adhikaansh jiv jantuoan ke sharir ka avashyak aang haian. is lekh mean manav sharir se sanbandhit ullekh hai. kasheruk dand hamari pith ki madhy rekha mean sir se dh d ke nichale sire tak phaili asthiy sanrachana hoti hai jo purushoan mean lagabhag 71 semi. tatha striyoan mean lagabhag 61 semi. lambi hoti hai. yah prayah pith ki tvacha se dhaki satah par ubhari huee dikhaee deti hai. ise merudand ya ridh ki haddi bhi kahate haian. kasheruk dand par hamara sir sadha rahata hai. isi mean merurajju ya sushumna surakshit band rahata hai. yah pasaliyoan ko ju dane ke lie sthan tatha padoan ki mekhalaoan ko sahara deta hai. isi se pith ki peshiyaan ju di rahati haian, jisake karan ham apane dh d ko avashyakatanusar age–pichhe ya parshvoan mean kuchh sima tak jhuka aur ghuma sakate haian.

sanrachana

kasheruk dand ek doosari ke pichhe ju di huee 26 (shishuoan mean 33) chhoti–chhoti asthiyoan ki bani haian, jinhean kasherukaean kahate haian inaka vitaran nimnavat hota hai:-
sabhi nikatavarti kasherukaoan ke bich–bich mean chapati antarakasheruk gaddiyaan hoti hai. inaka kendriy bhag komal lachila upasthi ka tatha paridhiy bhag tantumay upasthi ka bana hota hai. kendriy bhag ko majji kendrak kahate haian. gaddiyoan ke karan kasheruk dand paryapt lachila hota hai aur bahari aghatoan ko bhi sokh leta hai.  

jhukav

sidhe kh da hone par bhi kasheruk dand poornatah sidhi sthiti mean nahian hota hai. parshvoan se dekhane par isamean char jhukav dikhaee dete haian. ye oopar se niche ki or kramashah griva, vakshiy, kati tatha trik jhukav ya mo d hote haian ye jhukav kasheruk dand ko dridhata pradan karate haian, kh de rahane, chalane phirane aur dau dane mean sharirik santulan banae rakhate haian, jhatakoan se raksha karate haian tatha is tootane se bachate haian.  

praroopi sanrachana

pratham do tatha antim nau ko chho dakar sabhi kasherukaoan ki akriti lagabhag saman tatha nagadar aangoothi ke saman hoti hai. pratyek kasheruka tin mukhy bhagoan mean vibhedit hoti hai:-

1. kasheruk kay
2. tantrikiy chap
3. sandhayi prabardh

aang	koshika	sankhya
gardan	griva kasherukaean	7
vaksh bhag	vakshiy kasherukaean	12
kati bhag	kati kasherukaean	5
trik bhag	trikasthi	1 (shishuoan mean 5 kasheruk)
shroni bhag	anutrik	1 (shishuoan mean 4 kasheruk)

kasheruk kay

yah aangoothi ke saman thos evan mota hota hai tatha kasheruka ke agr bhag ka nirman karata hai.

tantrikiy chap

sentram par pichhe ki or ek kasherukiy ya tantrikiy hoti hai. tantrikiy chap se ghire hue sthan ko kasheruk randhr kahate haian. sabhi kasherukaoan ke ye randhr milakar kasheruk dand ki kasherukiy ya tantrikiy nal banate haian. isamean merurajju ya sushumna surakshit band rahata hai. tantrikiy chap ki pratyek bhuja do bhagoan mean vibhedit hoti hai—

vrint

yah tantrikiy chap ki bhuja ka sentram se ju da chhota evan mota bhag hota hai. nikatavarti kasherukaoan ke vrintoan ke bich donoan or ek-ek antarakoshik chhidr hota hai. is chhidr mean se hokar merutantrika tantrikiy nal se bahar nikalati hai.

phalak

yah tantrikiy chap ki bhuja ka pichhala, chapata aur patti sadrish bhag hota hai. yah doosari or ke phalak se ju dakar tantrikiy chap ka pashch bhag banata hai, jise kantikiy pravardh kahate haian.

sandhayi pravardh

tantrikiy chap se sat pravardh nikale hote haian. vrint tatha phalak ke milan sthaloan se donoan or ek-ek anuprasth pravardh nikale hote haian. phalakoan ke milan sthal se ek kantikiy pravardh pichhe ki or tirachha niche ki or jhuka hota hai. in tin pravardhoan se peshiyaan ju di rahati haian. vrintoan evan phalakoan ke milan sthaloan se donoan or do prakar ke sandhayi pravardh nikale hote haian:-

uchch sandhayi pravardh - ye chhote aur sankhya mean do hote haian aur oopar ki or nikale hote haian.

nimn sandhayi pravardh - ye bhi sankhya mean do hote haian aur ye niche ki or nikale hote haian.

oopar niche ki kasherukaoan ke ye pravardh paraspar sandhit hote haian. inake chapate sandhi sthaloan ko sandhiphalikaean kahate haian.

shirshadhara

kasheruk dand ki pratham kasheruka ko etalas ya shirshadhara kahate haian. yah khop di ke lie adhar ka kary karati hai. isake agale sire par do gol gadde hote haian, jisamean khop di ke donoan pashch ubhar sthit hote haian. isi prakar pratham griva kasheruka jise akshiy kasheruka kahate haian, khop di mean is prakar sthit hoti hai ki khop di ko saralata se ghumaya ja sakata hai.

kary

kasheruk dand manushy ke sharir ke lie nimn kary karata hai:-

• kasheruk dand mean jhukav hone ke karan isamean vistaran tatha sankuchan ki kshamata hoti hai, jisase manushy sir ya kandhoan par bhari bojh asani se dho sakata hai.
• kasheruk dand ke karan vaksh tatha udar ke aangoan ko suraksha prapt hoti hai.
• kasheruk dand se manav khop di ju di rahati hai.
• vaksh pradesh ki kasherukaoan se pasaliyaan ju dakar vaksh ka pianjar banati haian.

panne ki pragati avastha

adhar

prarambhik

madhyamik

poornata

shodh