“I think it’s first important to start with defining tendon health… And so I look at it as a multi-dimensional constructs composed of these domains that collectively define tissue capacity where health is maybe an alignment between the capacity and the environmental demand plus weighted by what the individual cares about.”
“We look at structure, we look at function, and we look at mechanical properties. And so those are sort of the big three that we would evaluate coming into the tendon lab. Again, all this is built upon what the individual wants to get back to, because I do think when we define tendon health, it needs to be contextually specific. Are they a sedentary, older individual that just wants to be able to walk pain free, or is it an elite basketball player who wants to be able to decelerate into a pull-up jump shot effectively without tendon pain. So I those are two very different examples and I think they require, while overlapping, different approaches per se.”
“Force at less than 150 milliseconds is actually a different measure than peak force.”
“Using B mode [ultrasound], while extremely valuable, you’re having to save the images in your head as you’re scanning somebody. Whereas with UTC, you’re able to set it on there, push a button, the computer collects 600 images every 0.2 millimeters and overlays it on one another. And you’re able to quantify the tendon structure and discriminate the aligned fibrillar structure with the disorganized tendon structure.”
“Trying to correlate structure and pain and structure and function and all that stuff, it can get a little messy… just taking the low back literature and saying, well, if you image 100 people off the street, 80% of them have some form of low back issue on imaging, but they’re all asymptomatic, so therefore, imaging doesn’t matter. I have a problem with that, and I think that’s where a lot of this stems from, unfortunately. And then obviously, some of the early work on the donut and the hole, and again, it’s phenomenal work, they’re phenomenal researchers, I’m not saying they’re not, I’m just saying that wanting to answer some of these, or continue an investigation some of these questions instead of just saying it’s a done deal and structure doesn’t matter.”
“If you have structural change, your likelihood of pain or symptoms increases, but the literature also supports that the normalization of structure isn’t necessary for someone to get out of pain. And I think that distinction is important.”
“If somebody comes in and they’re very hypersensitive and they’re so concerned and they have this almost kinesiophobic type approach in conversation, then I know that the language I use and how we describe imaging and the findings and this and that can have a drastic impact on their life, essentially. We need to take that seriously.”
“When trying to share what UTC is to people, I’ve used to a tree farm analogy actually where it’s like if you’re taking a drone or if you’re flying over a tree farm and you’re taking pictures every 0.2 millimeters. ⁓ If you see these aligned trees in a row, you’re saying, okay, these trees are a little bit, you know, they’re really strong, the farms running really well. But if you start to see the trees are wavy back and forth, and some are leaning one way, some are leaning the other, maybe a recent storm rolled through and they’ve got some work to do to get back to a good state. Or if you see the young trees, the saplings, maybe that’s the type three, the Echotype three, where they’re still growing or it’s patchwork, trying to repair a tendon. If there’s no trees, it’s more of that Echotype four.”
MRIs: “Sometimes they’re needed to evaluate maybe bony edema if they have insertional tendinopathy or maybe at the inferior pole of the patellar tendon, particularly in systemic tendon disorders, maybe it’s enthesitis, maybe there is some systemic issues going on and getting an MRI to evaluate, ⁓ some of the insertion would be helpful.”
“You need to load a tendon or else it forgets its a tendon. And so that is often the first line of defense.”
Paratenon: “I’ve had a few of those cases come in the clinic where with UTC there’s sort of like a halo sign around the periphery of the tendon.”
“I do believe a tendon can adapt and I’ve seen that even anecdotally with serial UTC over time…. We know what percentage in this couple millimeter space at the mid portion that was previously, you know, 50 % of this echo type one and 30 % of this echo type three. Now, a month later, we’ve re-imaged that area and we’ve seen some drastic improvements in the echo type one and decreases in the echo type three. To me, that says there’s continued ‘healing’ going on.”
“I believe structure matters, but like I’m not married to it. There’s, many other important things. And the example I would give would be, you know, maybe somebody’s pain is decreasing. Their function is increasing, but their structure is getting worse. In a sedentary person, all they care about is pain. They pain free, they’re gray, who cares what their structure is? They probably don’t, even though I probably would. In an elite athlete, yes, function matters, yes, symptoms matter, but I also think the structure matters. And so if that structure is going down while their function and pain are improving, we need to make sure that we keep an eye on that.”
“I do think it [structure] matters when it comes to the function piece. Simply because if we look at the tensile capacities, the echo type 3s are the type 3 collagen compared to the type 1 collagen. The echo type 3 is just immature, not able to withstand these tensile strains or capacities that the echo type 1 or 2 are. And so simply just basing our argument on that, you know, we think that having more echo type 1 and 2 is probably a good thing.”
“Tendons take time, both from a function, symptoms, but also structural standpoint. Sometimes structure, like a lot of the studies we’ve seen is structures not even changing after 12 weeks or 52 weeks.”
“The language of tendons is load and mechanotransduction, we’re speaking to the tendon and ⁓ the magnitude and the rate and the duration and frequency, et cetera, ⁓ that’s the language to lay down collagen and improve the alignment. so anecdotally, we’ve seen changes in a few weeks, ⁓ four weeks.”
“Tendons act as a buffer to muscles. So if we’re talking Achilles, the calf complex is important to assess and get an understanding of, whereas the quads would be for the patellar tendon. You know, that’s my bias is that tendons work as a buffer to muscles.”
“Where we often see patellar tendinopathy pop up is in a single leg CMJ in some of their eccentric capacities. And so particularly looking at the eccentric peak velocity or how willing the athlete is to drop into that bottom position of a CMJ. So the single leg CMJ more for the knee and and patella where the hop tests, you know, more for the calf, I would say.”
“Are your imposed demands aligning with your desired outcome? And so I think we need to start with separating what are we trying to cause via our interventions or what are we trying to do with our interventions versus the expected outcome and not confusing maybe the biological change, aka increased stiffness with the functional results, you know, decreasing pain or returning back to sport. So not confusing those two.”
“The strain based approach, strain being the primary mechanical stimulus that drives tendon adaptation… the, magnitude, the rate, the duration, frequency of strain, all of that determines, whether the response is healthy or whether it’s pathological… I do a combination of high force isometrics, heavy slow resistance or modified Kongsgaard program, and blood flow restriction… It’s really utilizing those three, BFR, HSR, HFI.”
“Like any intervention, it’s tailoring it to what their goals are and working backwards from that and meeting the person where they’re at, but being very clear on what adaptive response are we trying to elicit.”
“For midportion Achilles tendinopathy, likely decreased stiffness or increased compliance. Let’s do an intervention that will improve that stiffness.”
“I do think we just need more research in tendonopathic tendons because a lot of the heavy traditional loading research has been done in healthy tendons.”
BFR: “I just think for elite athletes who have high levels of mechanical strain, maybe their tendon cells are saturated from this mechanical stimulus. What’s another alternative to be able to provide a potential sufficient stimulus for adaptation? Okay. BFR works via more of the hypoxia, metabolic cascade stimulus. And so rather than adding more water to the already full cup of mechanical loading, let’s get that same adaptation or similar adaptation using a different pathway.”
“Maybe somebody’s 50% of their MVC is actually 7% strain. And so that 50% of their MVC or a lighter load is actually a stimulatory for adaptation.”
“45 second isometrics, again, very tribal when you bring up that discussion, but I do think sustained positions, loading the tendon in some form or fashion is often beneficial, particularly in the early stages. One, to build confidence. Two, to get some stimulatory effects into the tendon and start this motor reprogramming or whatever you want to call it. I think the moderate slow is working because you’re getting these people to exercise consistently and frequently, regardless of the load that they’re using. And so that’s absolutely advantageous.”
“If they have insertional Achilles tendinopathy, the literature does support minimizing some of that deeper end range dorsiflexion to minimize compression. The challenge is that same position is also the position where we can produce the most force. And so at some point you do want to get into those positions.”
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Tendon Lab Website: https://www.thetendonlab.com
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