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Thank you for the question. Answers given are for informational purposes only and are not meant to replace an exam by an in-person.
I am Dr. Sohaib, a Medical Internist (who deals with diseases of all the organ systems of body) and I will do my best to find an answer for you.
Dear XXXXX, honestly this does not seem to be related to your prostate.
The most likely cause for this appears to be a "Pinched Nerve" in the spine.
It is a condition characterized by abnormal excessive pressure over the nerves as they exit the spine.
Age related vertebral degeneration or disc prolapse is the usual underlying problem for this.
And the fact that it is related to posture also reinforce the diagnosis of pinched nerve rather than a prostate issue.
Your next step is to see your doctor, discuss the details I have mentioned and have an MRI of the spine done which is the most useful test to diagnose this problem with certainty.
The treatment is usually in the form of physiotherapy, pain medications, massage, and nerve block injections for pain control.
In severe case, surgery is the option (but it is rarely required).
Until you see your doctor, avoid bearing heavy weight.
Keep your back straight (avoid abnormal postures).
And can use Paracetamol or Ibuprofen for pain control (if required).
I hope this clarifies and answers your question.
I would have been worried too if I were at your place, but let me reassure you that this is a treatable condition and carries a good prognosis with appropriate management.
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