What is Shockwave & Is It Effective?

: On today's episode, what is shockwave and is it effective? Welcome to the podcast that gives you the most up to date, evidence based information on PHT rehab. My name is Brodie. I am an online physio, but I've also managed to overcome my own battle with PHT in the past. And now I've made it my mission to give you all the resources you need to overcome this condition yourself. So with that, let's dive into today's episode. Welcome back everyone. We are going to cover on today's episode, um, what is shockwave? Like how's it administered? And we're going to go through a paper that I found about its effectiveness, uh, with a few different variables. Um, this episode in particular is going to go out on the Run Smarter podcast, as well as my overcoming proximal hamstring tendinopathy podcast. Uh, pretty much because the title of this paper that I'm going to discuss is the sec it's titled sex differences. And. shockwave therapy outcomes in runners with Achilles or hamstring tendinopathy. So it applies to the hamstring tendinopathy, which makes it very relevant for that particular podcast. Um, but I haven't really done a shockwave episode in a while. Uh, I interviewed Benoit Matthew years ago. Um, he was, and is a shockwave expert to talk about, uh, the particular mechanisms and who's appropriate. I think the main takeaway from that episode was who's a good candidate for shockwave, which I'll go through today as well as a bit of a rehash. But yeah, this particular approach in this particular paper I found interesting, and therefore we're going to release it. And you know, I think the results of this paper and results of this was quite illuminating. So thought it'd be interesting to share. Adam. 1040 is one of the authors that I recognise in the list of the many that are in here. He's done a lot of research papers on runners, particularly ones on cadence. He's the one I refer to when looking at optimal running cadence and his particular paper was on taller runners can have a lower cadence, a lower optimal cadence than someone who has, who is shorter and has shorter legs. People with shorter legs tend to have a higher optimal cadence somewhere around like say 180 to 185 where someone with really long legs, maybe around 165, 168, those sorts of things. I digress. So that was the title of the paper. And let me go through the abstract and then I'll dive into the specifics of shockwave. So it says, Achilles and hamstring tendinopathies are common injuries in runners and shockwave therapy may be an effective treatment. The purpose of this study is to evaluate the association of sex, meaning gender, exposure, and hormonal contraceptives, menopause, the, how they say, triad-related risk factors, which is like low energy availability. I'll talk about that in a second. With the outcomes in the treatment of Achilles and hamstring tendinopathy. So they have a particular hypothesis that because with tendons, Tendons behave differently under certain conditions. And the role of estrogen or estrogen, if you wanna pronounce it that way, does seem to have some sort of effect on tendons. So if someone who has hormonal contraceptives or menopause or going through any particular phase of their menstrual cycle might affect tendons differently. How can we test it? Well, we can have a look at this particular paper. go through the data and see if someone has had treatment done. Does it matter? Does gender matter? If there's hormonal contraceptives, does that matter if someone's taking contraceptives compared to not? What is the effectiveness of shockwave? If someone isn't familiar with shockwave, it is essentially like a little handheld device attached to a machine. Kind of don't really want to say gun, but it's kind of like a It's got this like point at the end and you can apply it to the skin and it starts releasing shock waves. Nothing else, no injectables, no fancy electrical chemicals. It's just pressure. It's essentially like a pressure shock wave that kind of makes a zapping sound every second or so or sometimes a bit faster and can produce pain. Like it can stimulate pain, but it's just shock. And it ripples. deeper into your skin, as you can imagine if someone was to provide physical pressure shock, you can imagine that rippling down into deeper tissues. And that's essentially what it provides. It provides this local stimulus of pressure when conducted at a certain frequency at a certain depth can trigger certain things in your body. And so yes, my interview with chat about that and the mechanisms behind it. He mentioned that a good candidate for treatment of tendinopathy would be someone who has had it for a long period of time, we're talking three plus months. We could assume that it's in the chronic realm. It's low level and stubborn pain. So we're looking at someone who has a tendinopathy. that has had a one or two out of 10 dull, constant kind of ache through the tendon that doesn't really fluctuate with treatment. That's non-responsive to treatment, but doesn't really respond one way or another. We sort of, I kind of imagine this like a dormant, stubborn issue. And someone who's had an acute, quite painful tendon that just like severely fluctuates, they might not be a great candidate. Those who have like really chronic issues and widespread issues, really sensitive, really high levels of pain and the pain can like kind of radiate, have pins and needles, numbness, anything like that, I wouldn't think is a great candidate. We know for tendinopathies, the classic presentation is it tends to remain relatively localized. And so if you have had it for several months, If the pain itself is quite low level, localized and quite stubborn, doesn't really respond well to the slow, heavy progressive load that research shows is great for treatment of tendinopathies, then yes, you might be a good candidate for shockwave therapy. Okay. The paper continues to say the use of shockwave therapy for athletes with musculoskeletal pathologies has been increasing along with the growing literature, highlighting its efficacy and unique properties. Shockwave applies energy in the form of shockwaves to the area of the pathology. Shockwave may be applied to bone as well as soft tissues, including tendons, fascia and muscles. The energy applied may differ by mode and or delivery. And they talk about these two kind of modes that the shockwave machine can administer, one being radial or focused shockwave. Radial has lower peak pressures acts as like for more superficial structures, more to the surface of the skin. Whereas focused shockwave delivers higher amplitude waves at deeper depths into the body for, yeah, that, that would be for the radial mode. They say these therapies act or likely elicit various healing mechanisms, including the destruction of calcifications, angiogenesis, which is like the generation or proliferation of blood vessels. So angiogenesis in the inflammatory phase of tendon repair. They also say activation of cell signaling pathways through the release of adenosine triphosphate and anti-inflammatory and analgesic effects through the release of nitric oxide. So some people might be familiar with an analgesic effect that some tendons have. If you warm it up or you load it and that. pain tends to diminish and then you go by for the rest of your day for the next couple of hours and then it feels better. That is the analgesic effect. And as shown, the shockwave can have similar benefits. Additional factors may influence the development of tendinopathy and response to treatment in runners. Sex hormones may play an important role in the has been found to impact collagen synthesis and turnover as well as inflammatory pathways, crucial for tendon healing. These discoveries may be clinically relevant to females experiencing varying concentrations of estrogen during the menstrual cycle, pregnancy, or menopause, or by exposure to exogenous estrogen in the form of hormonal contraceptives or hormone replacement therapy. This brings... me to like an interesting point. I just finished listening to the conversation with Stacey Sims on the diary of a CEO podcast that was just released maybe one or two weeks ago at the time of recording. And she was mentioning that with tendon injuries, um, we need to be careful with tendon injuries during a female's menstrual cycle. And because of this response to estrogen and collagen turnover, tendons, the majority of a tendon is made up of collagen. And so when we stimulate the tendon, we need collagen turnover, almost kind of like an adaptation phase. We have a breakdown of collagen that gets triggered to rebuild collagen and then become stronger because of it. Kind of think of like, you know, what your muscles do when you go to the gym. So this collagen synthesis is really important and that turnover is really important, but it seems like estrogen. tends to impact negatively impact or slow down this process. And Stacey Sims was saying that during someone's menstrual cycle, its highest levels of estrogen are during the follicular phase. And it's, it's usually day 12 to 14 on a typical 28 day cycle. And so, you know, females may be susceptible to this increased risk of tendinopathies or a inhibition of rehab responses if they are in this particular phase of their cycle, if they're not taking some sort of contraceptive medication. And so, yeah, it's quite timely this has come up along with me just listening to that episode. If anyone hasn't listened to that and you're interested in this particular topic, I think that's a fascinating conversation. I continue. So the paper says there is some evidence suggesting that oral contraceptive pills may increase the risk of tendinopathy. Sex hormones may also be influenced by the nutrition status of the athlete. And now they're starting to talk about, they label in this paper, the female athlete triad, which is describing a medical syndrome where there's three things that interplay. which is low energy availability with or without a disordered eating. So you have, you're not eating a lot, not eating enough to support the energy that you are releasing. So that's the first interrelated play that they have. The second one is menstrual dysfunction and the third is low bone mineral density. So the combination of those things leaves an athlete very prone to dysfunction in the body. stress fractures, but also a lot of systemic issues and organ issues that might come into play. Most people may be familiar with red S as a term, it's relative energy deficiency in sports, meaning that if athletes, particularly some who are conscious about weight or wanting to keep aren't giving themselves the necessary nutrients to meet the demands of the running and exercise and stress and everything that the body, you know, requires fuel for. Yet the body can start shutting down because they're not, you're putting out all this energy but you're not giving the body the energy it needs. And so that's when these issues can arise. So they're talking about this in the context of hormone contraceptives in terms of does someone with low energy availability, are they at risk or do they have a change in response if we were to have a tendinopathy and therefore would it change their response if we do so administer shockwave? They say the purpose of this study is to evaluate the association with sex, exposure to hormonal contraceptives, menopause and triad related risk factors with shockwave outcomes in the treatment of achilles and hamstring tendinopathies. This was a retrospective cohort study. So they designed this study with previous data that has already been collected. It was actually from a single physician's sports clinic. They had a look at this one physician who has been conducting shockwave throughout the period of 2017 to 2021. So we're looking at a four year time span. where this physician has been collecting all this data from athletes, from collecting various questionnaires, gathering data, and then we can correlate that data, put it into a study and see what we find. So they said a diagnosis was made with a clinical history, a physical examination, and yes, some imaging if required. And then all patients needed to have taken several questionnaires and also overlapping their medical history, their sports activity, their bone health, weight related behaviors, menstrual history and function, any medication and this within this medication would include hormonal contraceptives. Then patients would take a certain pain and function questionnaire, both for like if you underwent a, it was called the visa A or the visa H, which is two different questionnaires for specifically for Achilles and specifically for hamstring. And they would take this questionnaire prior to the shockwave treatment and then throughout the treatment and then after treatment. And then we can see, okay, how did they respond? How did they respond? Females compared to males, female contraceptive medication compared to females non-contraceptive and start drawing all of these details together. And... I kind of like that it was one clinician because we know that, well, we sometimes can have some confidence that was administered at the same time or like administered by the same person. Usually if we have a large study with a large amount of therapists or conducting shockwave, like some people can be just really proficient with shockwave and some quite the opposite and some have different methods, some have different approaches, like it can be really messy. One thing I didn't like about this, they said that the pit... The inclusion criteria was, okay, they needed to self identify as a runner. They needed to have, um, a diagnosis with Achilles or hamstring tendinopathy. They need to have received shockwave and they needed to have completed the questionnaires before and after. Um, but within this inclusion criteria, like, yes, they have to have a diagnosis of a tendinopathy, but it could be an acute two week tendinopathy. It could be a two year. five-year tendinopathy, they didn't really include a time. And I would imagine that an acute tendinopathy would vary differently from a chronic tendinopathy, as I talked about with Benoit's interview, seems to be a good candidate would be a chronic tendinopathy. But if it goes way too chronic, if it's like 10 years of a tendinopathy, there's a lot of psychosocial influences that manipulate pain, and that can have particular um, different reactions as well. So studies are always going to have limitations. I just found that was one major one when looking at these, this inclusion criteria. Let's continue. So they say participants were, um, counseled to avoid the use of NSAIDs. So non-steroidal anti-inflammatory drugs during the duration of the shockwave treatments, and they said this was to avoid interruption of the inflammatory cascade that the shockwave has suggested to. be involved, it tends to promote or create this inflammatory cascade. And if you take anti-inflammation, then that could potentially hinder the healing process. So just so you're aware of that, participants typically received three to four weekly sessions with a three month follow up. And so when we're looking at these questionnaires, we're looking at that, a three month follow up. They said additional sessions were added based on the clinicians, the clinic response and their best practices, seeing if it's clinically rational to do that. So three to four weekly sessions. So they had three or four shockwave sessions done at weekly intervals. Um, but it was open to discussion if they did want to do a fifth or a sixth based on how they feel like they're trending. They said that. runners were canceled to participate in physical activity and continue running if desired throughout the treatment itself. So throughout this three to four week period, if the pain was consistently below a five out of 10 on the visual analog scale. So usually I say less than four would be ideal, but in this they say less than five, not a big difference, but just so you know. And then they look at these. Achilles and hamstring scores that they rank on their questionnaires and they use this What they call like a minimal meaningful change and What they're called. Well, they called it the minimal clinically important difference. And so they said that the smallest change they were looking for a Insertional Achilles tendinopathy would be a 12 point difference For a non-insertional Achilles tendinopathy, we're looking at a seven point difference. And for the hamstring questionnaire, we're looking for a 22 point difference. Meaning that if someone scores a certain score beforehand and then afterwards, if there's a 22 point improvement, then that is the minimal change we are wanting to say that this is clinically significant. So that's the aims I were looking for. In terms of how large the sample size was in terms of the demographics, they said that there was a total of 88 runners, including this study, um, about half with, uh, female to male. So there was 48 females and 40 males. The average age was 39. They looked at those with Achilles tendinopathy. There was 46 people with Achilles and there was 42 people with hamstring tendinopathy. the hamstring tendinopathy group comprised of 30 females and 12 males with similar ages. What did they actually find? Let me scroll down to the discussion. Okay, they say, as hypothesized, no difference was found in achieving the minimal clinical difference between sexes. So males and females responded equally. Additionally, no associations were found between those who had this triad-related risk injuries and shockwave outcomes. However, female runners who used an oral contraceptive were significantly less likely to achieve this clinically significant difference. These findings highlight the importance of understanding the effects of variables differentiating male from female athletes in efforts to optimize care. So if you used your oral contraceptives, you were significantly less likely achieve this difference. Now that we have my RunSmarter AI Assistant, if you're not familiar, there's like these mid-roll ads that are rolling out at the moment and this was released just a few weeks ago. You can ask this AI Assistant a question and it pulls out all of my RunSmarter resources to come up with an answer. And so... I haven't really talked about this in the PhD podcast, but there is going to be this service available to you as well. I'll discuss that in the next several weeks, but this is just one shockwave study, but I wanted to have a look at what the AI assistant thought of this. And so I typed in similar to what you would do with ChatGBT, except, you know, ChatGBT can use things like blogs and forums and like unreliable. non-peer-reviewed data, whereas this, check this out. So I typed in, how effective is Shockwave at treating tendinopathies compared to strength training? And here's what it came up with. It said, the effectiveness of Shockwave therapy compared to strength training for treating tendinopathies has been addressed in several studies. It says in a subheading, Shockwave therapy. Research indicates that Shockwave is beneficial for various tendinopathies, including chronic proximal hamstring tendinopathy. A study found that after shockwave treatment, 85% of patients experienced at least a 50% reduction in pain compared to only 10% in a traditional conservative treatment group. And it said that this treatment group consisted of exercise as well. Shockwave therapy works by stimulating healing responses such as neo-vascularization, which is just more blood vessels. and collagen synthesis in the tendon. Then it has as the next category, strength training. Strength training, particularly eccentric exercises is known to be effective in managing tendon injuries. Studies suggest that such exercises help facilitate tendon repair by loading the tendon appropriately. Moreover, incorporating strength training with shockwave can potentially enhance treatment effectiveness as shown in research where combining these approaches yielded better outcomes than either modality alone. And it references two different studies. This is the cool thing about this particular resource. You won't find ChatGBT doing this or anything like that. It is linking papers. It is linking resources and peer reviewed research papers from my own database, as well as podcast episodes I've done in the past. So it has linked with that particular response to papers. that has shockwave, Achilles versus proximal hamstring tendinopathy, as well as a few others. As well as my podcast episode with Miles Murphy talking about game changes in tendinopathy research. So he's brought up several points about this and this AI assistant has used that as a reference. So this is where I think we can tie a bow on it, not tie a bow, but like sort of come up with some nice conclusions. AI response was and continues to say, while shockwave therapy may provide rapid pain relief and support gradual healing, strength training focuses on mechanical loading of the tendons, promoting long-term strength and resilience. In a clinical setting, shockwave might be recommended when immediate pain relief is necessary or when patients are unable to perform exercises due to pain. Strength training is critical for the long-term recovery and prevention of recurrent. of recurrence from tendinopathies. In summary, shockwave can be effective in the short term for reducing pain associated with tendinopathies, while strength training is vital for long-term rehab and resilience. Combining both approaches may yield the most beneficial outcomes for patients. And so, yes, then after those responses, it lists several references that you can click on. You can listen to podcast episodes on this topic. You can listen to or read PDFs. research papers on this topic. Um, but I thought I'd just give it another followup. And so I continued to add to this conversation and I typed in how many shockwave sessions are recommended for short-term pain relief and the AI assistant spits out for short-term relief of tendon opethies using shockwave therapy, the recommendation, the recommended minimum is three sessions, typically administered weekly. This is considered essential. for achieving any therapeutic benefit, as the effects of shockwave therapy are accumulative. Some practitioners may suggest a maximum of 5 or 6 sessions as data indicates that improvements tend to plateau after this point. It is also noted that while benefits may start to become evident within a course of treatment, full effects can take up to 12 weeks after the last session. Therefore it's crucial not to expect immediate results after just three sessions. For instance, if a patient undergoes the minimum of three sessions, it is advised to pair this with a suitable rehabilitation program afterwards to optimize healing and strength. And then in terms of its references, it is referenced both of my podcast interviews with Benoit Matthew. So you don't have to go finding those episodes. You don't have to go listening for hours to find what you're after. this AI assistant will spit out those answers and then provide those references. So a very cool resource. I'm gonna continue using this for future podcast episodes as well. So hopefully you can enjoy this. What, no matter what podcast you are listening to this on, either the PHT one or the Run Smarter podcast, this will be available to you. There'll be a link in the show notes for you to start using this resource yourself. But hopefully this episode has touched. and maybe refresh your memory on Shockwave. If you haven't heard of Shockwave, hopefully it's provided some good illustrations and good explanations. And now we're kind of on the same page in terms of what the data shows. Yes, we can't go into the thousands of Shockwave research papers that are out there, but hopefully this is a nice little taster for you. So hopefully you've enjoyed this episode today and we'll catch you in the next one. If you are looking for more PhD resources, then check out my website link in the show notes. There you will find my free PhD 5-day course, other online content and ways you can personally connect with me, including a free 20-minute injury chat to discuss your current rehab and any tweaks you might need to make. Well done for taking an active role in your rehab by listening to content like this. together we can start ticking off all of your rehab goals and finally overcome your PHT.