What’s New

December 19, 2019:
As reported in Science Daily, researchers have discovered tendon stem cells for the first time, raising hopes that future treatments targeting the tendon stem cells could improve tendon healing. The study found that both tendon stem cells and scar-tissue-forming cells respond to platelet-derived growth factor alpha. If researchers could find a way to help the tendon cells respond more and the scar tissue cells respond less, the balance might be tipped to better tendon healing with less scar tissue. The lead researcher, Chen-Ming Fan of Carnegie Institution for Science, said that treatments based on this tendon stem cell discovery could be a game-changer for tendon healing. See their study published in Nature Cell Biology.

December 6, 2019:
Today I discovered that my domain name tendonpain.org accidentally expired when I missed the renewal notice that went into an obscure junk folder that has not had any email go into it in years (I had forgotten that junk folder even existed). Then my 30-day grace period for renewing the domain happened while I was evacuated from the California Kincade fire, which nearly burned down our home (the firefighters saved our home even though fire burned the hillsides on two sides within 15 to 30 feet of our home). We did not have power or internet for a while after the fire, so I was busy and did not even discover until December 6 that someone had taken over my domain and copied my entire site content word for word, page for page. I was not able to get the domain name back, but I filed a take-down notice for my content and got them to remove most of my content (they are still using my logo tagline and site description but the page content has been removed). The current tendonpain.org has no affiliation with me or my site. I have changed the name of this site to tendoninjury.org. I am sad that I have lost all my backlinks and that people will be led from those links to the site that tried to steal my content rather than to my site, but I will continue to build on the content here and will carry on.

August 4, 2017:
Causeway Therapeutics has received a £1m seed investment to help with the development of its promising new treatment for tendinopathy. “Replacement of Type I collagen with Type III collagen is characteristic of tendinopathy; loss of miR29a in human tendons drives an increase in Type III collagen production. Causeway’s lead product, TenoMiR™, is a replacement for the natural miR29a that is depleted in tendinopathy.”

July 24, 2017:
On July 21, 2017, the company Samumed announced successful completion of a Phase 1 trial of their topical treatment for chronic tendinopathy. Phase 1 trials only establish safety (not efficacy), but now the treatment can move into Phase 2 trials. From the press release: “Samumed’s investigational drug is a topical gel containing its novel small molecule compound SM04755. In June, Samumed presented promising data from its preclinical studies of SM04755 at the 2017 EULAR Annual Meeting in Madrid, Spain. In preclinical tendinopathy models, SM04755 reduced inflammation, inhibited fibrotic markers, increased tendon regeneration markers, and improved tendon structure microscopically and macroscopically. In addition, SM04755 promoted in vivo tendon healing in single and repeat collagenase-induced tendinopathy models in rats.”

September 15, 2015:
Today I changed the name of the site’s domain from tendinosis.org to tendonpain.org, but you can still find the site using either url (tendinosis forwards to tendonpain). I had originally started the site in 2002 under the name tendinosis.org because that was the new terminology at the time, as people were moving from the term tendinitis to tendinosis. Now, over a decade later, tendinopathy is becoming the preferred term. Our new name of tendonpain.org encompasses both tendinosis and tendinopathy. I hope the new name will make it easier for people to find the site when they are searching for information. Tendinosis means chronic degeneration without inflammation, whereas tendinopathy does not imply anything about the etiology. Since researchers are still debating the etiology of these chronic injuries, they are using the term tendinopathy more frequently to avoid implying anything about whether there is inflammation or not. Based on recent studies, it looks like there is some inflammation on a cellular scale, but we don’t know yet what role it plays in the chronic nature of the injury.

September 9, 2015:
As of now, the Replicel clinical trial is still accepting new patients to study the use of its new cell therapy in treating Achilles tendinosis/tendinopathy. If you have had Achilles tendinosis/tendinopathy for over 6 months and are interested in being in the clinical trial, you can follow the link for more information.

July 29, 2015:
Study finds positive value to allogeneic mesenchymal stem cell injections as a treatment for chronic tendinopathy. This was a small study (only 12 people) and had no placebo control group, so more research is needed. The patients were followed for 52 weeks though, and the safety/efficacy data looked promising.

July 2015:
Cell Therapy Ltd (now known as Celixir) announces positive phase 2 clinical trial results of Tendoncel®, a topical regenerative treatment for chronic tendon injury. “Patients using the non-invasive Tendoncel® topical gel for 21 days experienced a clinically relevant and statistically significant improvement in their tendon injury. Reporting an average improvement of 70% on the DASH disability scale and 74% improvement on the PRTEE scale, Tendoncel’s results exceed those expected of injectable treatments and have the advantage of painless topical application.”

July 11, 2015:
Study finds differences in glutamate receptors and inflammatory cell numbers in rotator cuff tendinopathy in painful vs pain-free patients, and finds differences in glutaminergic and inflammatory gene expression between injured vs healthy tendon. It is interesting that although the painful vs healed tendinopathy patients looked the same on the outside ("no significant differences in basic tendon histology between painful and pain-free tendons"), there were measurable differences in glutaminergic and inflammatory pathways going on inside. Note from the study: "Glutamate is an important amino acid involved in many key physiological processes including cell metabolism, pain sensitisation and collagen synthesis."

April 27, 2015:
A team at the University of Glasgow is researching a possible way to correct the imbalance in Types I and III collagen in tendinopathy. They discovered that a microRNA called miR-29a helps regulate the balance; restoring higher levels of miR-29a restores collagen type I to pre-injury levels relative to type III. Trials have been done in cultured cells and in mice, and horses will be next. One of their papers can be found here.

April 1, 2015:
A study in the Sept 2014 International Orthopaedics reported that mesenchymal stem cells improved tendon healing following rotator cuff repair. The study was presented at the American Academy of Orthopaedic Surgeons 2015 Annual Meeting and is just appearing in the news now. After 6 months, 100% of the stem cell treated patients had healed compared to 67% of the non-treated controls. After 10 years, 87% of the stem cell treated repairs were still intact vs 40% of the controls.

April 1, 2015:
University of Delaware has established a Tendon Research Group to study acute and chronic tendon injuries and treatments.

March 31, 2015:
I updated the site’s format to make it responsive to mobile devices and tablets. It should now work on all devices, and it looks more modern as well.

Oct 30, 2014:
I added some new information to the injury pathology section and added a few more reference links [65] [66]; some researchers have noted inflammatory cells in biopsies of tendinopathy/tendinosis and are encouraging more research into the role of low-level inflammation in the injury process. They are not suggesting that inflammation is the cause or that anti-inflammatories are the cure, but they are calling for a better understanding of the role of inflammation in the chronic injury process.

Oct 16, 2014:
I just created a Facebook page for tendinosis.org, so you can now follow our updates on Facebook here. If you “like” our page you will receive our research updates in your Facebook feed.

Oct 15, 2014:
New software for ultrasound interpretation has been developed that will aid in the diagnosis and treatment of tendinosis by pinpointing areas needing treatment and by helping track treatment efficacy. See the echoMetrix website for more information about this new patented diagnostic tool.

Sept 6, 2014:
A Canadian company, Replicel, is starting a clinical trial in Sept 2014 of their new autologous cell therapy treatment for tendinosis. They will be injecting Achilles tendinosis injuries with fibroblasts collected from the dermal sheath of patients’ hair follicles. Replicel reports that these fibroblasts derived from hair follicles produce five times more Type I collagen than skin-derived fibroblasts.

Nov 2013:
In September/October 2013, Ortho Cell reported that a clinical study of autologous tenocyte therapy for lateral epicondylitis was successful. The study was published in the December 2013 American Journal of Sports Medicine. [59] Patients in Australia can go to clinics that work with Ortho Cell for this treatment; the patient has an initial appointment during which a tendon biopsy is collected from a healthy tendon and sent to Ortho Cell for processing, and then later the patient returns for an injection of the tenocyte cells isolated and grown from the biopsy.

Feb, 27, 2013:
I gave the site a much-needed update and new format, and I added a discussion forum. I hope the discussion forum will give people a place to meet and help each other. If you want to join, send me an email and I can approve your membership

I'll continue to post brief updates here, and I'll try to add new research to the site as I become aware of it. The Facebook feed has more research updates than I post here, so follow the Facebook feed if you want the very latest information.

New Site Name:

We had changed the name of the site from tendinosis.org to tendonpain.org in 2015 because the information here covers both tendinosis and tendinopathy. We have now changed the name again in December 2019 to tendoninjury.org because of an unfortunate domain problem; please know that the current tendonpain.org site has no affiliation with this site and if any of our content continues to appppear there it is without our permission.

Facebook Feed:

We post links to new research on our Facebook feed, so that is the best way to keep up with the latest news. Follow us on Facebook.

Tendon Research News:

Science Daily reports on the recent discovery of the existence of tendon stem cells
Lead study author Chen-Ming Fan of Carnegie Institution for Science is quoted in the Science Daily article, "Tendon stem cells exist, but they must outcompete the scar tissue precursors in order to prevent the formation of difficult, fibrous scars. Finding a therapeutic way to block the scar-forming cells and enhance the tendon stem cells could be a game-changer when it comes to treating tendon injuries."

University of Glasgow: Scientific breakthrough unlocks potential novel tendon therapy
”Tendinopathy is essentially the result of an imbalance between collagen type-1 and type-3 and we have discovered the molecular cause. This breakthrough has allowed us to find a way to alter the levels of collagen type-3 in tendons, with the ultimate aim to get patients with tendon injuries better quicker."

Biologic augmentation of rotator cuff repair with mesenchymal stem cells during arthroscopy improves healing and prevents further tears: a case-controlled study
“This study showed that significant improvement in healing outcomes could be achieved by the use of BMC (bone marrow concentrate) containing MSC (mesenchymal stem cells) as an adjunct therapy in standard of care rotator cuff repair. Furthermore, our study showed a substantial improvement in the level of tendon integrity present at the ten-year milestone between the MSC-treated group and the control patients.”

Treatment of Lateral Epicondylosis Using Allogeneic Adipose-Derived Mesenchymal Stem Cells: A Pilot Study
“This pilot study on the safety and efficacy of allo-MSC injection for treating chronic LE demonstrated that the intervention was safe and efficacious in improving pain, performance, and anatomical defects for more than a 52-week follow-up period. This is the first clinical study using allogeneic MSCs to treat chronic tendinopathy.”

Cell Therapy Ltd announces positive Phase II clinical trial results of Tendoncel ™, a first-in-class topical regenerative medicine for severe tendon injury
“Patients using the non-invasive Tendoncel ™ topical gel for 21 days experienced a clinically relevant and statistically significant improvement in their tendon injury. Reporting an average improvement of 70% on the DASH disability scale and 74% improvement on the PRTEE scale, Tendoncel’s results exceed those expected of injectable treatments and have the advantage of painless topical application.”

Mechanotherapy: how physical therapists’ prescription of exercise promotes tissue repair
“Mechanotransduction is the physiological process where cells sense and respond to mechanical loads. This paper reclaims the term “mechanotherapy” and presents the current scientific knowledge underpinning how load may be used therapeutically to stimulate tissue repair and remodelling in tendon, muscle, cartilage and bone.”