Additions can be made by replying to this thread (https://www.peyroniesforum.net/index.php/topic,7299.0.html).
Reviews
2019 - The use of penile traction therapy in the management of Peyronie's disease: current evidence and future prospects (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6444402/)
2016 - Traction applied to Peyronie's disease cells reduces cellular fibrosis. (http://www.jurology.com/article/S0022-5347(16)02769-5/abstract)
2016 - Penile traction therapy for Peyronie's disease—what's the evidence? (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4893512/)
2013 - Penile traction therapy and Peyronie's disease: a state of art review of the current literature (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3547530/)
2011 - Non-invasive methods of penile lengthening: fact or fiction? (http://www.ncbi.nlm.nih.gov/pubmed/20868389)
Traction
2019 - Outcomes of a Novel Penile Traction Device in Men with Peyronie's Disease (Restorex) (https://pubmed.ncbi.nlm.nih.gov/30916626/)
2018 - Penile traction therapy with the new device 'Penimaster PRO' is effective and safe in the stable phase of Peyronie's disease (https://pubmed.ncbi.nlm.nih.gov/30365247/)
2017 - Effect of Penile Traction and Vacuum Erectile Device for Peyronie's Disease in an Animal Model. (https://www.ncbi.nlm.nih.gov/pubmed/28923308)
2015 - The Effect of Duration of Penile Traction Therapy in Patients Undergoing Intralesional Injection Therapy for Peyronie's Disease (http://www.ncbi.nlm.nih.gov/pubmed/25804087)
2014 - Acute phase Peyronie's disease management with traction device: a nonrandomized prospective controlled trial with ultrasound (http://www.ncbi.nlm.nih.gov/pubmed/24261900)
2012 - A retrospective comparative study of traction therapy vs. no traction following tunica albuginea plication or partial excision (http://www.ncbi.nlm.nih.gov/pubmed/22900621)
2012 - Combination of penile traction, intralesional verapamil, and oral therapies for Peyronie's disease. - PubMed - NCBI (http://www.ncbi.nlm.nih.gov/pubmed/22024053)
2011 - Traction therapy for men with shortened penis prior to penile prosthesis implantation: a pilot study. - PubMed - NCBI (http://www.ncbi.nlm.nih.gov/pubmed/21492409)
2011 - Effect of penile-extender device in increasing penile size in men with shortened penis: preliminary results. - PubMed - NCBI (http://www.ncbi.nlm.nih.gov/pubmed/20102448)
2009 - Penile traction therapy in Peyronie's disease (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2924711/)
2009 - A pilot phase-II prospective study to test the 'efficacy' and tolerability of a penile-extender device in the treatment of 'short penis' (http://www.ncbi.nlm.nih.gov/pubmed/18990153)
2008 - Penile traction therapy for treatment of Peyronie's disease: a single-center pilot study. - PubMed - NCBI (http://www.ncbi.nlm.nih.gov/pubmed/18373527)
2008 - Tissue Stretch Decreases Soluble TGF-β1 and Type-1 Procollagen in Mouse Subcutaneous Connective Tissue (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3065715/)
An excellent new review of traction has been added, posted in 2016.
Penile traction therapy for Peyronie's disease—what's the evidence? (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4893512/)
As expected, it concludes that the evidence is strong for traction and it appears to be a good treatment, even if there are not that many studies and sample sizes were small.
I highly recommend you all read the experimental data , it states that the mode of action is called "mechanotransduction." in which collagen fibers remodel themselves with traction.
Newer little study on rats 2017, added to the list.
Effect of Penile Traction and Vacuum Erectile Device for Peyronie's Disease in an Animal Model. (https://www.ncbi.nlm.nih.gov/pubmed/28923308)
Very interesting study!
Simple summary, traction great for bends, VED might actually be better for healing erectile function issues and decreasing the chance of re-injury or progression.