Brief Answer:
Explained in detail below.

Detailed Answer:
HI.Narendrakumar,
Thank you for the query.I have read it..&would try to inform you about possibilities & ways to releave it.
Stiffness in neck&back...the possible causes are as below...
-Faulty sleeping posture including type of pillow used can cause it..Correction of posture would help.
-In this Era of computers...the most common sufferers are..those persons working on computers for maximum hours of the day.&here continuos stress to back&neck muscles is common cause for the problem./Faulty sitting posture/position&height of table chair.. can cause pain in back&neck.
Correction of the posture,having light exercises in between,small breaks to relieve continuous stress can relieve it.
-Weak bones due to nutritional deficiencies of calcium,vitamin D can add to the pain These need to be assesed by getting their blood levels tested&supplimentation with doctors advise.
-Cervical spondylitis &Thorasic spondylitis.This can be age related or Prolonged posture & stress related problem.
This can be confirmed by expert examination by an orthopedic surgeon&confirmed by imaging investigations(X ray,MRI,CT scan.. advised as per need).This problem causes pressure on nerves emerging out from spinal foramina...leading to muscle spasm of the muscle supplied by the nerve.
Here after investigations &assessing type of spinal lesion & also degree of it's pressure on nerves..treatment is advised.
It can be oral anti inflammatory drugs,vitamin B12, calcium,vitamin D...as per need. Local injection of steroids help in few cases/physiotherapy/ Surgery may be needed in few adverse conditions.
This is in short possibilities in your type of symptoms . please consult your family physician &Orthopedic surgeon if needed,for more personalized advise.
I hope that helps.
Any follow up query is welcome.
Thanks

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