Tendinopathies

Tendons. The tendon is the part of the muscle that attaches to the bone and transfers force from the muscle to the bone (1). This is how we get the body to move because the muscles activate and pull on the bones. The crazy part is that this seemingly occurs instantaneously. We do not have to think about moving. We just go. When we stand up from sitting, we stand and start to walk. Crazy. To keep a tendon healthy, loading the structures is important (1). We will cover this a bit later. Tendons get upset over time and with repetitive activities or sudden increases in activity, or going from sedentary (sitting all day) to moving more (walking or standing for longer). The terminology often used with tendon injuries are: tendinitis (acute or new injury) and tendinosis (chronic, nagging). Both terms have their meanings, but how does anyone know the state of a tendon? Much of the tendon terms are based on onset or time. Tendinitis is a fresh injury to the tendon in which we will develop inflammation – redness, swelling, and stiffness. Tendinosis is a term used for long term and continued tendon pain and symptoms. However, does everyone know when exactly something started to hurt outside of trauma or a fall? Probably not. It just suddenly hurts, which is the body telling you there is a problem and we have to solve it. Tendinopathy is a more direct term that basically tells us that the tendon is having an issue and needs help to stimulate repair.

Overuse based tendinopathies develop in the rotator cuff, the elbow as tennis elbow and golfer’s elbow, the patellar tendon (jumper’s knee), gluteal tendons (greater trochanteric syndrome of hip bursitis), and the Achilles tendon (2). The general first step is to temporarily decrease the intensity and amount of the aggravating activity to help stimulate the repair process. The tendon will follow a three step process: inflammatory (1 week), proliferation (creating collagen and extracellular matrix, up to 4 weeks), and remodeling and maturation (continued healing to help reorganize the tissues, beyond 4 weeks) (3). A dysfunctional tendon will become pathological. The pathological tendon will change its make-up and structure (loss of collagen organization), alter the mechanical properties (type III collagen formation and deposition of proteins), and change the blood flow around the tendon which leads to the tendon not quite healing (3, 4). So if the tendon can no longer take the stress and load it was intended for, the tendon never regains its power and strength and continues to be weak and may fail.

Tendons generally respond to loading because loading the tendon (adding weight) helps the tendon to adapt; however, too much loading can lead to the development of tendon pain and pathology (3, 4). This concept creates a conundrum. The ability for the tendon to accept mechanical loading is limited by pain, the pain reduces the load needed, and the tendon loses its means to adapt (4). Pain further causes disuse and results in worsening conditions of the tendon, the muscle, and the ability to use that area for daily activities (4). Thus, the tendon never fully heals and receiving a medical intervention (a cortisone shot) to address the pain does not result in the immediate increase in the loading of the tendon because the medical intervention does not address the tendon adaptation properties (4). Sometimes a cortisone shot is beneficial because it can help decrease the pain in some patients to allow for the mechanical loading of the tendon. However, sometimes a cortisone shot may not work for a given patient or multiple iterations of cortisone may be detrimental to the tendons, ligaments, and bones. Not to further complicate the matter, but much like all other conditions in the human body, pathology can exist without pain (4). What we do know is that a degenerative tendon rarely recovers the normal structure despite having the ability to normalize and positive structural changes to the tendon do not always relate to improvement (4). Complicated, right? The research is ongoing in trying to understand the mechanisms behind pathological tendon adaptations, mechanical loading principles, and recovery. Docking and Cook (2019) believe that mechanical properties are likely the explanation for adaptation in a pathological tendon and they highlight that the current evidence does not state this as a fact.

Areas that are continuing to develop in helping to boost recovery from injury are shockwave therapy (5), low-intensity ultrasound (5), platelet-rich plasma (PRP), stem cell-based therapies, and blood factor treatments. These treatments are still undergoing research and may or may not be beneficial. What we have seen thus far in the world of physical therapy is a mixed bag of results from various treatments that are regenerative in nature. At the SHOP, we do not provide these treatments as they are not within our scope of practice. Always consult with your physician about information, cost, and risk versus benefit of these additional treatments. Ask the people who know the answers to your questions, not an AI.

Dry needling is still being explored as a means to help treat tendinopathy along with the addition of ultrasound guided dry needling through protocols and research by the American Academy of Manipulative Therapy’s (AAMT) Dry Needling Institute and their national leading education in MSK Ultrasoundography. At the SHOP, we have training in these dry needling protocols that are currently being researched and raw study results have shown excellent outcomes for various tendon protocols.

If you live in Springfield, MO and the surrounding area, let The SHOP help evaluate and treat your tendinitis, tendinosis, or simply put, tendinopathy. Do you want to learn more or get started with treatment?

References

1. Andarawis-Puri N, Flatow EL, Soslowsky LJ. Tendon basic science: Development, repair, regeneration, and healing. Journal of orthopaedic research : official publication of the Orthopaedic Research Society. 2015;33(6):780-784. doi:https://doi.org/10.1002/jor.22869

2. Millar NL, Silbernagel KG, Thorborg K, et al. Tendinopathy. Nature Reviews Disease Primers. 2021;7(1). doi:https://doi.org/10.1038/s41572-020-00234-1

3. Christelle Darrieutort Laffite, Blanchard F, Soslowsky LJ, Benoit Le Goff. Biology and physiology of tendon healing. Joint bone spine. 2024;91(5):105696-105696. doi:https://doi.org/10.1016/j.jbspin.2024.105696

4. Docking SI, Cook J. How do tendons adapt? Going beyond tissue responses to understand positive adaptation and pathology development: A narrative review. J Musculoskelet Neuronal Interact. 2019;19(3):300-310.

5. Smallcomb M, Khandare S, Vidt ME, Simon JC. Therapeutic Ultrasound and Shockwave Therapy for Tendinopathy: A Narrative Review. Am J Phys Med Rehabil. 2022;101(8):801-807. doi:10.1097/PHM.0000000000001894