Lack of tissue renewal in human adult Achilles tendon is revealed by nuclear bomb (14)C
Four articles on PainSci cite Heinemeier 2013: 1. About PainScience.com 2. Deep Friction Massage Therapy for Tendinitis 3. Repetitive Strain Injuries Tutorial 4. Achilles Tendinitis Treatment Science

PainSci commentary on Heinemeier 2013: ?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided wherever possible.
There is basically no turnover in tendon tissue in adults (as measured in the Achilles tendon in this experiment).
And how do we know this? Because NUKULAR BOMBAS! The atomic signatures of the era of nuclear bomb testing are still written into the tendons of people who were alive at the time, trapped like bubbles of ancient air in an ice core.
Incredible. Very cool science. Indeed, probably the coolest tendon study that has ever been or ever will be.
UPDATE: This finding was confirmed for healthy tendon in a later study. But in un-healthy tendon? That’s a different story. There is turnover there! Which is hard to interpret. See Heinemeier et al.
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
Tendons are often injured and heal poorly. Whether this is caused by a slow tissue turnover is unknown, since existing data provide diverging estimates of tendon protein half-life that range from 2 mo to 200 yr. With the purpose of determining life-long turnover of human tendon tissue, we used the (14)C bomb-pulse method. This method takes advantage of the dramatic increase in atmospheric levels of (14)C, produced by nuclear bomb tests in 1955-1963, which is reflected in all living organisms. Levels of (14)C were measured in 28 forensic samples of Achilles tendon core and 4 skeletal muscle samples (donor birth years 1945-1983) with accelerator mass spectrometry (AMS) and compared to known atmospheric levels to estimate tissue turnover. We found that Achilles tendon tissue retained levels of (14)C corresponding to atmospheric levels several decades before tissue sampling, demonstrating a very limited tissue turnover. The tendon concentrations of (14)C approximately reflected the atmospheric levels present during the first 17 yr of life, indicating that the tendon core is formed during height growth and is essentially not renewed thereafter. In contrast, (14)C levels in muscle indicated continuous turnover. Our observation provides a fundamental premise for understanding tendon function and pathology, and likely explains the poor regenerative capacity of tendon tissue.
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
- No long-term effects after a three-week open-label placebo treatment for chronic low back pain: a three-year follow-up of a randomized controlled trial. Kleine-Borgmann 2022 Pain.
- Exercise and education versus saline injections for knee osteoarthritis: a randomised controlled equivalence trial. Bandak 2022 Ann Rheum Dis.
- Association of Lumbar MRI Findings with Current and Future Back Pain in a Population-based Cohort Study. Kasch 2022 Spine (Phila Pa 1976).
- A double-blinded randomised controlled study of the value of sequential intravenous and oral magnesium therapy in patients with chronic low back pain with a neuropathic component. Yousef 2013 Anaesthesia.
- Is Neck Posture Subgroup in Late Adolescence a Risk Factor for Persistent Neck Pain in Young Adults? A Prospective Study. Richards 2021 Phys Ther.