Considerations on recurring running injuries in relation to pelvic tilt

© April-November 2016 Paul Cooijmans


Since I started running in 1986, a number of recurring injuries have limited the amount of training I can do, both in volume and intensity. Frustrating as this is, I have mostly accepted the situation, and dealt with it by restricting the amount of training, adapting my training methods, improving my running technique, trying different shoes, and doing exercises; all of those measures helped to some extent, but without solving the problem for real. On occasion I have consulted a few doctors and therapists, but no one ever identified a possible structural cause of the injuries. Doctors have noted a collapsed forefoot, therapists have advised exercises and seen a scoliosis (which a doctor then denied), but these observations were never integrated into a coherent explanation of what was going on.

Only in recent years I have begun to suspect what causes me to be able to train so little. I will clarify my current insights below, assuming that I am not unique and that many runners are probably suffering from more or less the same problems, so that this may help some to understand how things hang together. It took me decades to figure these things out, and it would have helped tremendously if someone had explained it to me thirty years or so ago.

The recurring injuries and other complaints

Running injuries

The left achilles tendon

The left achilles tendon, together with the narrow muscle/tendon that runs from the outside of the lower leg along the ankle to the bottom of the foot, has given problems since 1986 uninterruptedly. The direct cause is traction on the outside of the ankle, as a result of the left foot developing over the little toe, so over the outside of the forefoot. I feel this happening, and it can also be seen by the callus formation under the forefoot toward the little toe, and a little by the wear of the shoe sole (there is not much wear though, since I mainly run on soft surface).

The right knee

Problems with the right knee started in the 2000s, beginning with irritation and pain behind the knee cap, followed some years later by pain inside the knee near the outer meniscus. While weakness of upper leg muscles is said to be a cause of that, it also plays a role that the knee is bent inward a bit, in an X-position, so that the outer meniscus is compressed.

The right groin area

In a few long periods since 1986, but not always, I have had pain in muscles in the right groin area. On one occasion I actually pulled a muscle there while sitting on a couch doing nothing. This is not atypical for a groin injury. Sometimes, the right hip "snaps".

Other complaints

The lower back

In 2010/2011, I had a herniated disk in the lower back, between L5 and S1 on the right. Apart from causing the usual nerve pain on the outside and back of the right leg, it also worsened or evoked the knee problems, especially the bad tracking of the knee cap, probably by affecting the leg muscles.

The neck

Since about 1985 at least, I have had a rather stiff neck and sometimes pain in the neck on the left side, which radiates to the left forehead above the eye. It can also be hard to turn my head to the left.

The jaw joints

My jaw joints feel like they are wearing out, and the right one often appears to dislocate, causing a sharp pain in the right ear.

The apparent deviations of skeleton and posture

From bottom to top:

The left foot

A few doctors have noted that the left forefoot collapses under pressure.

The right leg

The right ankle and knee are bent inward a bit (more than on the left leg). The right upper leg is thinner than the left one.

The pelvis

It appears that the pelvis is tilted laterally such that the right side is higher than the left side. The pelvis is also tilted forward, so that the belly is protruding.

The back

The lower back used to be rather hollow, but since the herniated disk operation of 2011 it has been much flatter, and my back has also been much stiffer ever since. Then higher up in the back there is a sideways curve which is convex to the left (scoliosis). The upper part of the trunk also leans backward.

The shoulders

The right shoulder is clearly higher than the left.

The neck and head

The neck and head are tilted to the right compared to the shoulders, and pointing forward. A bizarre feature is that the left ear is attached lower to the head than the right ear, but because of the tilt of the head, both ears are still level relative to the horizon…

Analysis of the deviations in relation to each other and to the recurring injuries and other complaints

I believe the left-right pelvic tilt is the central and causal phenomenon. It corresponds to an effective leg-length discrepancy. It is not certain that the actual bones of the legs are of different lengths (although that is common), it may also be that the legs are, for instance, attached to the hips differently, causing an effective discrepancy in leg length. A direct result of the lateral (left-right) tilt is the forward pelvic tilt; apparently a pelvis can not just drop on one side, it has to rotate in the perpendicular (front/back) plane at the same time. This forward rotation (anterior pelvic tilt) therefore is not just a matter of weak abdominal muscles, as is often claimed, but rather an anatomic necessity, and can not be simply corrected by strengthening those muscles. I have done abdominal exercises for decades, the relevant muscles are long of armed concrete, but that has not changed the forward tilt of the pelvis. As long as one hip is lower than the other, the forward tilt remains.

A way to momentarily resolve the pelvic tilt is to stand with bent knees, holding the knees more or less over the toes. In that position, the bending of the knees neutralizes the sideways pelvic tilt (the longest leg bends a bit more) and the pelvis can then be rotated backward to its neutral position easily.

Another effect of the uneven pelvis is the foot development over the outside of the left foot (this may be related to what some call "supination"). This is a compensation for the lack of leg length there; the leg, as it were, senses it is too short, and extends itself by standing on the outer rim of the foot. For better understanding, one may walk around on one shoe for a brief while; one will find that the shoeless foot tends to develop over the outside of the forefoot to match the length of the other leg. Or, one may reach for something very high; one tends to stand on the outsides of the forefeet to be able to reach as high as possible. In general, a leg can elongate itself by standing on the outside of the foot and rotating outward, and can shorten itself by standing on the inside of the foot and rotating inward.

While running, the shortest leg thus tends to develop over the outside, which causes traction on the outside of the ankle and oblique forces in the achilles tendon, hence the recurring problems there.

The right (longest) leg compensates for its excess length by bending inward at the ankle and knee (causing "pronation", I suppose) and/or rotating inward in the hip. This inward bending compresses the outer meniscus, resulting in damage to that meniscus and eventually arthrosis. Bad tracking of the knee cap may also relate to this compensation, as do, I think, problems in the hip area like irritation of the adductor attachments and "snapping" of the hip. I am not certain how these hip problems are caused exactly; it may be the slight inward rotation of the leg, and/or it may be that the head of the femur is forced toward the outside (the high side) of the hip as a result of the pelvis' not being level. That would cause extra traction on the adductor muscles.

There are a few more ways for legs to compensate for a length difference, but I have mentioned here only those that I see in my own legs.

Also, the aforementioned forward tilt of the pelvis causes both legs to bend inward at the ankles and knees, in addition to these compensation effects of the left and right legs. This explains why both legs are bent inward, but the right more than the left. When the pelvis is pulled backward by muscle force, the legs straighten a bit.

As for the back, the hollow lower back (caused by anterior pelvic tilt) and left-right unevenness will have contributed to a deterioration of the spinal disks, at one point resulting in a herniated disk (the direct cause was loud sneezing). Higher up, the scoliosis to the left may be a compensation for the lateral pelvic tilt, and in turn causes the shoulders to be uneven, and causes the neck and head to bend the other way (to the highest shoulder). The part of the spine where the scoliosis resides also leans backward, probably as a compensation for the forward pelvic tilt, and this backward leaning, in turn, makes the neck and head point forward. Stiffness and pain in the neck and sometimes head result. Apparently, headaches above the eye can radiate from the neck. I suspect, incidentally, that tics like head shaking and teeth banging also contribute to stiffness and pain in the neck, and to the wear of the jaw joints and teeth.

Finally, I observe that at least several of my direct relatives display similar combinations of features and complaints, especially the development of the left foot, the scoliosis, and the pain in the right knee (arthrosis in some). Also many herniated disks.


First, it must be noted that almost everyone has a degree of leg length discrepancy, or at least so one says. According to doctors, such a discrepancy only needs treatment if it exceeds 2 centimetres; others, like therapists, say that much smaller discrepancies, such as 5 mm, may already cause problems. I do not know what is true, but I do suspect that my discrepancy (measured at 6 mm meanwhile) is causing injuries and other complaints. I think that running works as a magnifier for skeletal and postural deviations, so that small deviations that one never notices in normal life become sources of injury. Below are a few approaches that may neutralize the harmful effect of pelvic tilt.

Training approach

Relaxed interval training is better than continuous running; during the fairly long breaks, the muscles and tendons regain their resilience so that they are able to do their protective work again in the next run. With continuous running, muscles tend to lose their elasticity after several kilometres, and therewith lose their ability to catch off the damaging effect of a leg length difference. To anyone who suffers from recurring running injuries, my first advice would be to quit continuous running in training (not in races) and to rely on relaxed interval training as the primary ingredient of running training. The worst advice to give to a (injured) runner is probably to stick to easy endurance runs for the time being.

Running technique

Since bending the legs can nullify or reduce a pelvic tilt or leg length discrepancy, the way to go is to use the natural spring action of the legs to absorb the impact of striking the ground, rather than to rely on shoe soles with built-in shock absorption. Legs can only function as springs when they are bent at the ankles, knees, and hips. The muscles and tendons then work reflex-wise as natural shock absorbers and can compensate a fair amount of unevenness (the longest leg simply bends a bit more). To learn about the right technique one may acquaint oneself with concepts like natural running, Pose method, and Chi running. I dare not advise minimalist shoes with very thin soles and no shock absorption, but I do believe that shoes with little or zero heel-to-toe offset are helpful in learning the correct technique.

Shoe inserts

An inlay of certain thickness in the shoe of the shortest leg can be used to correct (part of) the discrepancy. One may try this (as an additional measure) if the other two approaches do not suffice. I have some experience with this meanwhile: Half a year's experimentation with a simple extra inlay of 3 to 5 mm in the left shoe suggests that, in my case, the development of the left foot normalizes instantly and the achilles problems disappear and stay away. I can not observe a clear effect on the other deviations and injuries (mostly in the right leg) as yet.

Addition July 2016

I have now had a foot therapist examine me for possible deviations. It has been found that my left leg is 6 mm shorter than the right, and that my ankles go inward while walking and running. He did not mention the deviant development of the left foot or the collapsing of the forefoot, but did note there were warts under the foot, which I had always taken for abnormally formed callus. His advice was not to treat the leg length difference with an inlay in this stage, but first have my running analysed in a specialized running store and let them take my measures for shoes of their recommendation.

I did that, in a store for which I won a check in a recent race. They said the inward bending of the ankles is not problematic because I run with forefoot landing, so the pressure is already off while the inward bending occurs. On the video it can be seen that the right ankle bends inward more than the left, and that the left heel leaves the floor a bit earlier than the right, presumably because the left leg is shorter. The foot development was deemed neutral, and no deviant development of the left foot was noted (I think that is because I have trained myself to run neutral with the left foot, apparently with some success). I ended up buying the advised Inov-8 Trailroc 255; I really wanted shoes with "zero drop" from heel to toe, but they did not have those, in any case not in combination with some shock absorption. This Trailroc has 6 mm drop.

I tried the advised shoes for several weeks and had to stop using them then because I got ever more pain in the right knee. Apparently, the inward bending is not good for the knee after all and causes compression of the outer meniscus. I think the problem is that the soles are too thick and the "drop" too high.