Brief Answer:
Most likely pelvic floor dysfunction.

Detailed Answer:
Hello,
Thanks for posting your query on this forum.
Have gone through your details

Most likely its Pelvic floor dysfunction which includes a group of disorders causing abnormalities of bowel storage and bowel emptying.However detailed investigations as well as physical examination of patient would be required in order to reach a particular diagnosis.

Pelvic floor dysfunction can be caused by a number of specific conditions. These include:

(Rectocele,Paradoxical Puborectalis Contraction,Levator Syndrome,Coccygodynia,Proctalgia Fugax,Pudendal Neuralgia)

The pelvic floor is a sheet of muscle through which the rectum passes and becomes the anal canal.
The most important part of evaluating a patient with suspected pelvic floor dysfunction is a thorough medical history and detailed physical examination, including an examination of the pelvic floor.

Tests adviced are-

1)ENDOANAL/ENDORECTAL ULTRASOUND-Probe is introduced in anal canal and rectum after applying enema and images are generated on screen by help of waves.

2)ANORECTAL MANOMETRY TESTING
Information provided are-
-how the rectum responds to stool entering the rectum.
-function of reflexes in the anus and rectum necessary to pass stool can be determined

3)NERVE MOTOR LATENCY TEST
Nerve which supplies rectum and anal canal is manually irritated and force of contractions are measured.

4)VIDEO DEFECOGRAPHY
A x-ray machine takes video pictures while the patient sits on a commode, recording the movement of the muscles of the pelvic floor as the patient evacuates this will be a very important test in your case as it will record what exactly is happening when you try to evacuate in normal position.

5)BALLON EXPULSION STUDY-
A ballon small is placed in rectum.Time taken to expel ballon in sitting position will be observed.It will tell patency of rectal muscles.

6)Digital and proctoscopic examination of Canal should be done in physical to see the size of internal or external hemorrhoids.

Now as per your query,No most likely its not because of Hemorrhoids.However a detailed investigation as suggsted above is required to reach a final diagnosis.

I hope i answered your query well,Feel free to follow up.

Regards

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