Patellar Tendinopathy for Runners
Patellar Tendinopathy for Runners
Tendinopathy is a general term referring to any pathology within a tendon, including patellar tendonitis and tendinosis. Patellar tendinopathy (PT) is usually a relatively straightforward diagnosis for several reasons. Pain is typically localized at the base of the patella (upper portion of the tendon) or the tibial tuberosity (lower portion of the tendon).
Interestingly, in runners the most common presentation is at the tibial tuberosity whereas jumping athletes such as volleyball or basketball players typically develop PT at the base of the patella typically. (reference 1-2) Additionally, when other structures such as the fat pad, are involved the pain and location can be more variable.
Tendon related pain tends to be very localized on the tendon and predictable in that more load consistently causes more pain that lasts longer than less load. It will also follow a “warmup phenomenon” in which symptoms are often worse in the morning or after prolonged periods of inactivity, but once you get moving around again, symptoms begin improving. The development of PT occurs over an extended period of time with a gradual onset of symptoms. Often, there have been repeated bouts of higher training loads without sufficient recovery for the tendon specifically. Although your muscles and cardiovascular fitness may recover and adapt rather quickly, generally in a matter of weeks, tendons are very slow responders, taking months to really change and adapt to training loads. Because of this, runners must be mindful to maintain a slow progression in training volume, intensity, and vert. Descents are particularly relevant as downhill running increases stress on the knee by as much as 50% for a 5% decline such as running down Rampart Range Road to Balanced Rock in Garden of the Gods. (reference 3)
PT can be a big headache for many runners as the margin for error can typically be quite narrow. For this reason, of this it can be easy to exceed your tolerance and have setbacks that delay your return to prior training levels. Once you start moving in the right direction, this margin of error begins to expand towards that of normal levels before symptoms fully resolve. Following are three things I typically implement to help people improve symptoms and tolerance to running.
1. Isometrics (reference 4-8)
When a muscle contracts it can become longer, shorter, or stay the same length referred to as eccentric, concentric, and isometric respectively. In 2015, some research in the tendinopathy world that really shook things up, found that a series of isometric contractions could reduce pain by an average of 5 points on a 0-10 scale. That’s huge! Since then, other studies with more subjects and examining other tendons have been less impressive. Clinically, I have seen a similar variation: isometrics have taken some patients’ pain away completely and have no effect on others.
But even if you’re in the latter group, isometrics have numerous numerous benefits that greatly aid greatly in the recovery and adaptation of tendons. For instance, they can negate the effects of stress shielding, which occurs when the unhealthy aspect of a tendon is “shielded” from load by the healthy portions of the tendon through swelling of the extra cellular matrix (space between tendon cells). While this phenomenon is great at reducing stress to the unhealthy portion of the tendon acutely, we ultimately need to be able to get load through that portion of the tendon to create a stimulus for adaptation. A series of isometric contractions can help to do this by creating a lot of time under tension, which aids in squeezing out some of that extra cellular fluid and allowing more load in subsequent exercises during that session to apply more stress directly to the unhealthy area.
2. Tempo-no, not the running workout (reference 9-11)
Typically, heavier, and faster movements are not tolerated well in initial stages of PT. While “heavier” probably inherently makes a lot of sense, most people are surprised to learn that the rate at which something, such as a tendon, is loaded can be more important than the external load on the tissue. When you do the leg press with three times your body weight (BW), a single patellar tendon is experiencing 5x your BW and a loading rate of 2x BW/sec. Compare that to the landing phase of a vertical jump where the same 5x BW is experienced, but the loading rate is 38x BW. That’s a huge difference we need to be considerate of and approach in a methodical manner.
I like to use a metronome to help control tempo. Not only does it aid in keeping things slow, but it engenders consistency between reps, sets, and sessions. Additionally, pairing movement with the auditory piece helps with developing better motor control (resulting in better movement efficiency or smoothness), which is an important factor in restoring capacity to prior levels and beyond.
3. Increase cadence (reference 12-15)
There are two cases where I will undoubtedly address cadence, and they invariably go hand in hand. The first, is the location of your foot strike relative to your center of mass (COM). When the foot strike is well in front of the COM, we see more stress being shifted upstream to the knee and hip regions. The second, is the absolute number of steps per minute you’re taking, or cadence. As I discussed with patellofemoral pain in the October issue, we see a decrease in patellar tendon forces, much like those at the patellofemoral joint when increasing cadence as little as 5% and no more than 10% from your preferred normal. Therefore, this helps you improve tolerance by decreasing demands and has the effect of relative rest. I have seen good success with this approach in allowing people to return to running more quickly or maintain some level of running during the rehab process.
There is very little research on the relationship between cadence and developing pain or injuries subsequently. However, it does appear that a higher cadence yields fewer injuries or pain development for bone stress injuries (such as stress fractures) and around the knee. What constitutes a low cadence? The only hard threshold mentioned in the literature to date and has aligned with what I see clinically is, 165 steps per minute. If you are below this number, you will likely benefit from working on your cadence. If you are already at 165 or higher, you may benefit somewhat, but the gain will be less profound. Remember that this is just one variable and injuries are always multifactorial, requiring interventions from different relevant angles to address the issue fully.
If these steps don’t do the trick for you, please don’t hesitate to reach out for help to me or another trusted health care professional. You can connect with me via phone at (719) 270-3155 or email at runmental@gmail.com.
Happy running!
Refereneces:
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