Hi Adhiksa,
Here are some studies that may help you to hunt down the info you want. You should be able to hunt them down with the title and the researchers names.
Review: The effectiveness of non-invasive treatments for active myofascial trigger point pain: A systematic review of the literature
Luke D. Rickards --this one lists a lot of trigger point studies that may give you those session, duration info standards you are looking for. A Cochrane review would be fantastic for similar.
Test-retest reliability of myofascial trigger point detection in patients with rotator cuff tendonitis
Abdullah M Al-Shenqiti and Jacquelline A Oldham -- this one will be good to have just to demonstrate test-retest reliability.
Study protocol: Treatment of myofascial trigger points in common shoulder disorders by physical therapy: A randomized controlled trial. Carel Bron, Michel Wensing, Jo LM Franssen and Rob AB Oostendorp -- a study protocol, but missing duration, etc.
Good luck with your study! Very interesting.