CAPA si_aug_1990

The Longer and the Shorter Leg

Pages: 2-9
Year: 1990
Notes on S.I

Notes on Structural Integration – August 1990 – 90/1

Volume: 90/1

From the block model it becomes immediately evident why differences in leg length are highly relevant in the field of Structural Integration. The cranial bordering plane of the thigh segment is then not horizontal, and so the pelvic segment which rests on it is not horizontal in the frontal plane either. It will be lower on the shorter leg, and gravity will tend to push it out laterally in the same direction. Side-tilt and side-shift are both toward the side of the shorter leg. This enforces a modification of the inter- and intrasegmental characteristics of the pelvis described earlier (Notes on S.I. 87/1, p.32). Side-tilt and side-shift are related directly to the difference in leg length. Of the “unipolar system” there remain only segmental rotation around the vertical axis and intrasegmental standard torsion. The “bipolar system” of front-to-back balance is not touched by this further differentiation.

A difference in leg length is always present if only for the simple reason that absolute symmetry does not exist in anatomy. The primary interest from the point of view of Structural Integration is with whether the left or the right leg is the shorter or longer one. Because of pelvic side-shift the midline of the body will be convex to the side of the shorter leg, at least in relaxation. The degree of this convexity is secondary. But knowing its direction will help to avoid increasing this difference in leg length inadvertently, which would constitute disintegration. It should also sharpen perception and assist in finding specific and appropriate means for horizontalizing the pelvis consciously.

The problem has been approached earlier (“The Shorter Leg”, Notes on S.I. 86/1). The results were inconclusive, however. A main reason for this was a premise chosen wrongly at the outset. The study went from a direct causal relationship between the difference in leg length and rotations. It has become clear by now that these two issues must be analyzed separately. There exist some hints though which point toward a connection of some kind between the two. But to be able to state such a relationship concretely depends on having described and understood each issue in its own right thoroughly. This paper attempts to clarify the left/right issue further for the lower girdle. The main focus will be on the pelvis. But the situation at the other levels where the lower girdle segments meet- and where there should be horizontal planes – is of course also of vital interest.

The method for determining the shorter and the longer leg given earlier was the one used in medicine. In the client standing easy the relative heights of the iliac crests are compared. The results of this method are good if the difference is marked. It must be noted however that it is “indirect” in that not the top of the legs but the slant of the cranial border plane of the pelvic segment is diagnosed. There is no objection to this of course from the structural point of view as it assigns primary importance to the pelvis anyway. However, there exists a method which is more specific to the field. Since Ida Rolf identified gravity as the primary factor determining structure, all structural analysis begins with registering gravity’s impact on structure. The behaviour of the pelvic segment in the gravity field indicates this effect. Pelvic side-shift is the decisive diagnostic sign in the field.

A modification of the simple block model has already been implied in this approach. The pelvis is considered as resting on two “pillars”, the legs. These are thought to be made up by “half-segments”, those of the foot, the lower leg, and the thigh. But a functional complication needs to be addressed first.

Many people seem to be able to function in two different modes concerning the “pelvis on the legs”. In a more stable and relaxed arrangement which could be called “static stance” the weight of the body rests firmly on both legs. The shorter leg bears more weight than the longer one. The situation reminds one of a three-legged table which is inherently stable. In what could be called “dynamic stance” the weight is carried more or mostly by the longer leg. The body is on top of it. Because there is only one beam of support, this arrangement is labile and must be balanced permanently by muscles, the functional element. This would resemble a table with only two legs!

Energy expenditure is minimal in static stance. This stable arrangement on two legs can be managed and maintained easily and economically. It is not favorable for movement, however. Especially if this is translational as e.g. in walking it takes a lot of activating energy to come out of the stable arrangement. So it pays for the body to go into the dynamic “one-legged” stance when movement is intended. This takes more energy to be maintained but allows to initiate movement by letting go. Movement is (slightly) down initially instead of up first. The gravity center of the body is high and so the system has more potential energy.

A hypothetical “two-legged” table must always be held; but it can be moved, turned, and tilted easily. A “three-legged” table, especially if it is lopsided to fit the situation of the body in its static arrangement, must be heaved up on two legs first if one wants to handle it similarly.

Dynamic stance works easiest if the body is balanced straight on top of the longer leg, with the pelvis horizontal on it. There is a qualitative difference between the two regimes, i.e. they function according to completely different principles. And when the possible postures between them are examined, with the economical premise in mind, it turns out that there is no smooth transition between the two. Starting with stable stance, which is most economical in an absolute sense, and shifting the weight slightly in the direction up onto the longer leg, it can be felt that holding this stance takes clearly more effort. Going stepwise more and more toward the dynamic arrangement, energy expenditure is reduced again until one stands balanced on the longer leg. So there exist two minima concerning effort, with the dynamic regime taking somewhat more energy than the static one. But any stance in between requires more effort than dynamic stance.

The situation is exemplified by the “three-legged” table. It takes no energy when standing on all three legs. It takes some to balance it on two legs. But any arrangement between the two takes a lot more.

The situation is not so absolute with the body because its parts are not as rigid as those of a table and because other mechanisms also seem to play a role. The dynamic arrangement at its minimum is not completely one-sided as in standing on one leg. Some support still comes up through the other leg. So dynamic stance is shifted a little to the side of the shorter leg. This seems to function very much like the outrigger of a Polynesian boat. The longer leg carries the bulk of the weight of the body. Any disturbance is then usually down in the direction of the shorter leg which catches it and brings the weight back up again more towards and over the longer leg. Static stance is similar to a stable equilibrium, while dynamic stance represents more the labile or unstable equilibrium of mechanics. It is not exactly in labile equilibrium – no real system ever is -, but it is always a little to the same side, that of the shorter leg. It could be called a “biased labile equilibrium”.

This has clear advantages because the nervous system knows what to expect and can regulate dynamic stance in one and the same functional pattern with only quantitative adaptations. But also somatically this would seem to make sense because the hip joint of the longer leg and the structures securing it would not be permanently under the whole load but could “breathe”.

There emerge some structural consequences. As far as the method is concerned it seems obvious that when comparing different structures or one before and after Rolfing the same regime must be chosen. Generally the static one seems that of choice because structural preferences are expressed much more clearly.

Another aspect is not clear yet but might turn out to be relevant for structural analysis. One has sometimes the impression that some people stand and even move regularly in the static regime while others seem to prefer the dynamic one as their home position. Because continuous or repeated function shapes structure, it should be possible to observe the impact on structure of either regime, whichever is the preferred one. Perhaps this will turn out to be along the lines of structural dynamics.

A Study

The study presented here had several objectives. It first wanted to check on the incidence of left and right longer leg. It is known that the left is more often the longer one. It then sought to shed some light on where the shorter leg loses length by comparing the levels of knee and ankle joints in both legs and establishing some notion of where the thigh segment meets that of the pelvis, also for the purpose of comparison. A series of complications arose in the process. They seem worthwhile to be reported in order to help avoid mistakes and warn against oversimplification. More advanced hypotheses may also be formulated this way. Not all of the problems are solved, of course.

In a first attempt I had the clients stand with the feet together. The rationale had been the hypothesis that the body tries to horizontalize the pelvis through various adaptations. In clients with a marked difference one observes often that the longer leg is abducted. This reduces the length of its vertical projection and seems to serve the purpose of bringing the pelvis away from its marked side-tilt more toward horizontal. Other such mechanisms are perhaps external rotation and knee flexion or hyperextension which would all reduce the length of the longer leg. Stance with closed feet would eliminate such adaptations.

Sometimes this posture produced indeed a much clearer and marked side-tilt. With other clients however the pelvis seemed to become more horizontal to such a degree that it was difficult to decide which leg was longer. In easy stance the difference was distinct, however! This proves that the hypothesis is certainly not true generally. The observation suggests the following modification of the hypothesis. Bilateral symmetry is without a doubt an ordering principle for the left/right dimension. It is reasonable to assume that if violation of symmetry is marked the body takes adaptive measures to reduce asymmetry in order to assure easy functioning. But to understand deviations from symmetry as shortcomings only is apparently false.

A functional principle seems to intervene which demands a certain degree of asymmetry, also in order to assure easy functioning. The nervous system controls and regulates function, i.e. movement and posture. It would be an unnecessary overload without profit if it had to choose between two symmetrically opposed but otherwise identical patterns all the time(1). One of them is suppressed, the other preferred. To secure it firmly it helps to anchor the difference in structure. Then the influx of sensory data which is the essential base for monitoring function is unambiguous and permits the dominant pattern to manifest automatically. So for ease in the physical sense – minimal energy consumption symmetry is ideal. For “neurological” ease a certain degree of asymmetry is necessary. It would be interesting to know where the optimum is. But generally the actual structural state will be shifted more in the direction of asymmetry. For, function also determines structure, and the dominant functional pattern in conjunction with gravity will over time shift the structure more and more away from normal and into the aberration.

A practical reason for discarding stance with closed feet was the fact that it introduces considerable strain in the body, changing the relationships. If an abducted or everted foot of a collapsed external is forced to stand parallel to the other, the lower leg is distinctly higher over the foot than in easy stance.

<img src=’https://novo.pedroprado.com.br/imgs/1990/1035-1.jpg’>
Fig.1 – Locked-knee internal in dynamic (1) and static (2) free stance. Reversed left longer leg; the iliac crest in front is higher on the left side. In sleeve-supported stance (3) a homogenous right longer leg appears. The posterior superior iliac spine is higher on the right side (4).


First I palpated the posterior part of the iliac crests, comparing their heights, standing behind the client. Then I did the same with the anterior aspects of the crests from in front. When they were lower on the same side in front and back, the functional tests confirmed the finding. But sometimes they were contradictory. To explain this standard torsion and sagittal shift need to be considered.

Because of standard torsion the left iliac crest runs closer to horizontal. The right one is more slanted, higher in back and lower in front. When the difference in leg length is small, the posterior superior iliac spine can be higher on the right side, the anterior superior iliac spine lower, than on the left side.

Another phenomenon must be taken into account. When asked to “stand easy” the mind naturally focuses on standing, and with that most people shift their pelvis forward. Regular internals and symmetrical externals then often show a functional anterior shift, and regular externals are also more forward. The gravity center of the whole body is so relatively far back, and the gravity line, along which the body is supported, passes through the back of the pelvis. The posterior part of the crests then determines the higher side. Clients must be brought more toward the structural point without overdoing it, and this means always that the pelvis must shift back more or less. Then the gravity line passes more in front, and often what appeared to be a right longer leg shows to be a left longer one. These considerations only turned up during the study. It must be suspected that some of the “right longer legs” are really longer on the left side.

Locked-knee internals pose a special problem. Their mechanical regime is not free stance and qualitatively abnormal. Integration must go from the regular internal posture. This is artificial for them, however. As a compromise I took the pelvis back to about normal, “no shift”, or a little in front of it, but in any case in some sort of free stance.

The main functional test for pelvic side-shift brings the client close to “normal stance”. Usually the pelvis is shifted forward or the belly is contracted or the chest is raised when clients extend against the floor. All this must be prevented. When relaxing slowly the pelvis shifts in the direction of the structural side-shift into the aberration. As a short version the client is asked to let the weight of his upper body come down on one leg, then the other. The movement will be down on the side of the shorter leg, up on the other. Care must be taken that the legs don’t move lateral.

When the right leg is the shorter one, the two movements are often asymmetrical in another sense. On the shorter right leg the pelvis is on top of the leg, conforming to the “pelvis-on-legs” model. But on the left leg, which is longer, the pelvis appears to sink down medial of the thigh, pushing it out lateral. The left side is then not truly on top of the longer leg, and it looks as if the movement on this longer side were down. Kneeling in front of the client with the hands placed on his hips helps to avoid this mistake.

Another version lets the client bend his upper body sideways over each hip. Here another complication must be regarded. The upper body is slanted regularly over and toward the side of the longer leg. So because of the structural bias the trunk often bends easier over the side of the longer leg. Not the ease of movement must be assessed with this version but on which side the trunk must go more over the higher “ledge” formed by the hip.

<img src=’https://novo.pedroprado.com.br/imgs/1990/1035-2.jpg’>
Fig. 2 – Schematic drawing of homogenous right longer leg, homogenous left longer leg, reversed left longer leg, right longer leg with ankle reversal (modified from Rolf, p.62, III. 4-29).

Knees and Ankles

At the knees the medial clefts of the joints are palpated and compared in slight Folding. With some practice one “sees” the different heights of the axes of rotation. The condition is that Folding is done correctly.

At the ankles it is easiest and reliable to palpate the joints simultanously. The hands come from below and in front. With the thumb and the index finger I go around the extensor tendons backwards. Then I change direction more cranial to find the distal edges of the tibiae. The medial side, palpated by the thumbs, is usually more relevant. Slight Folding opens the joint optimally and makes diagnosing easy.

Pelvic Fold

The question is still open where the thigh half-segments meet the pelvic segment. The block model simply draws a horizontal line, but the situation is of course more complex. Anatomically, and looking from the front, the slanted line along the inguinal ligament from pubes to anterior superior iliac spine is most suggestive. A front-to-back plane laid through it would go about through the hip joint. This would be an important spot functionally because the rotational axis for flexion and extension between pelvis and thigh goes through it. It should be horizontal, but it is hard to determine. It is also relatively high on the pelvis and would seem to assign a lot of what belongs to the pelvis to the thigh segment.

But another point of view offers itself. Imagining flexion in the hip joint as anterior tilting of the pelvis with legs fixed it is obvious that everything which belongs to the pelvis and is below the axis of rotation goes back. Looking from in front, the pubes are the lowest defined and “hard” part of the pelvis. They go back most. Everything which belongs to the thigh stays in place where it is. Now the point along the slanted line of the inguinal ligament can be sought where the pelvis moves back most with regard to the thigh remaining still. This is not exactly at the pubes because the tissue lateral to them, that of the adductors, goes back with it.

The point is a little higher, just outside the inguinal ligament. It is close to the point of Ida Rolf’s schematic drawing where the line coming from the pubes turns out and horizontal. It can be seen directly – and the two sides can be compared – in slight Folding. Initially, as usual, only the pelvis should tilt anterior and begin to shift back, with the upper body and the knees not moving yet. The tissue sinks back most there. This can also be felt very clearly. Kneeling in front of the client, the fingers are placed flat in the groin, and the tips sense exactly where the tissue recedes most.

This “pelvic fold” is lower than the hip joint and not distinguished anatomically in any way. It seems to possess purely structural relevance. In the side-view, the midline through the thigh and pelvic segment forms one straight line which is vertical ideally. With Folding, the angle in this line would appear at the level of the pelvic fold.

In back, the points moving back most are the tuberosities. They are lower than the pelvic fold. A plane indicating the border between thigh and pelvic segment would go through pelvic folds and tuberosities. It would not be exactly horizontal but slanted down in back.

The height of the pelvic folds was also compared in the study. If the fold is higher on the side of the longer leg, too, this is called a “true longer leg”. If the fold is reversed, a “false longer leg”. The “longer leg” is defined as stated by the cranial border plane of the pelvic segment being higher. A “homogenous” longer leg means that the knee and ankle levels are also higher. “Reversal” indicates that one of these levels is lower in the longer leg. A “complete reversal” indicates a lower knee as well as ankle joint in the longer leg. If a context is clear, a “longer leg” means a homogenous longer leg, a “reversed leg” one with knee and ankle reversal. The term “reversal” may appear as a little strange in connection with “longer leg”. But it must be remembered that structurally it is not interesting if a leg is somehow shorter or longer. Gravity implies that the ground, thought to be horizontal, is the absolute reference line. So the “longer leg” is really that which “reaches higher”. In the “higher leg” it is of interest whether the other levels below, where half-segments meet, are also higher or not. This should provide some information about where the “higher leg” gains its length, i.e. which of the half-segments is longer than in the shorter leg.

<img src=’https://novo.pedroprado.com.br/imgs/1990/1035-3.jpg’>
Fig.3 – Homogenous right longer leg, left longer leg, reversed left longer leg (“true” version), and reversed left longer leg with pelvic fold reversal.

Results and Discussion

All adult clients coming in during a 3-week period were examined. A few had more than one session but were counted only once of course. Five clients with severe (medical) pathology including orthopedic surgery in the lower girdle were excluded from the sample. The results are shown in Table 1.

The percentage of right longer legs (33%) seems a little high, higher than in tentative overviews where it had been closer to 20%. Part of this may be due to the size of the sample which is small to permit definitive statements. Another part may be the result of mistakes as a consequence of the difficulties which arose during the study. Those concerning the functional anterior pelvic shift have been mentioned. Related to this is the lack of doing the full range of tests for side-shift and side-tilt consequently. It often takes more than one attempt to teach clients to sense their structural point. For some it is even impossible to learn extension against the floor quickly enough which is a prerequisite for testing.

The main question is of course where the longer leg “gains” length or the shorter one “loses” it.


In the foot one must certainly assume a structural factor. The architecture or “construction” of the foot as determined by the fascial net influences the height of the ankle hinge. There is of course always an “ossary factor”, too: the difference in the size of the bones in the left and right foot also plays a role. Sometimes one sees clearly that one foot is “bigger” than the other and that this is at least in part because of the different size of the constituent bones.

It is a little surprising though that in 38 of the 60 clients the ankle is higher on the side of the longer leg. It can be expected that equalizing the ankle heights contributes directly to reducing the difference in leg length and horizontalizing the pelvis. With the others there arises an obvious predicament. With the ankle reversal, equalizing the heights should augment the differences in length. The pelvis would tend to be side-tilted more, which would constitute disintegration.

Lower Legs

Structurally one would expect the right lower leg to be shorter because of standard rotation. Its tibia is rotated externally while the left one is more in line. Often the right lower leg is more abducted, too. But in the majority of cases the right lower leg seems to be the longer one! The only explanation is that the right tibia tends to grow longer than the left one (ossary factor).

<img src=’https://novo.pedroprado.com.br/imgs/1990/1035-4.jpg’>
Fig.4 – Drawing interpreting “true” and “false” reversed left longer leg schematically.


There is little possibility for structural intrasegmental variation as far as length is concerned because only one bone is present. The ossary factor of the femur is prominent. It has two aspects. First, the absolute length of the shaft and that of neck and head plays a role. Secondly, the angle between them is relevant.

There is an impression that the left femur and therefore the thigh tends to be longer, with some exceptions in evidence.

<img src=’https://novo.pedroprado.com.br/imgs/1990/1035-5.jpg’>
Table 1 – Frequency of left and right longer legs, homogenous and reversals. In parentheses the number of pelvic fold reversals.


The structural factor is more important in the pelvis. Because of standard torsion the right side appears not only as wider and flatter but also shorter in the long axis of the body; the left side is narrower, deeper, and longer (Notes on S.I. 87/1, p.34). This might explain the reversal of the pelvic fold in the left longer leg. When the leg difference as measured at the crests is small, the left side of the pelvis would “reach farther down” because the bone as indicated by the line from anterior superior iliac spine to pubes is positioned steeper than on the right side.

The three fold reversals in the right longer leg could only be explained by the ossary factor. At least with one of these clients the bones of the right side seemed massively bigger in size than on the left. It appears that so far the ossary factor has been underrated in the pelvis, i.e. asymmetries resulting not from position but differences in the size of bones.

Three dominant patterns can be distinguished: the homogenous right longer leg, the homogenous left longer leg, and the reversed left longer leg. For the practice, the second appears as the least difficult. Equalizing ankle heights and reducing pelvic torsion would tend to add total length to the shorter right leg. Also better organization of the right leg with its “rotational conflict” at the knee brings it more in line and should add length.

The longer right leg presents more difficulties. Lowering the ankle or raising that of the left leg would also help to horizontalize the pelvis. But reducing the knee “conflict” and normalizing pelvic torsion should raise the pelvis on the already longer right leg more.

With the reversed longer left leg the degree of the difference in leg length appears to be important. The situation is not very problematic if it is small. The tendentially disintegrating effect of equalizing ankle heights is often less than the potential gain from organizing the right leg more in line and reducing pelvic torsion. If the difference is large however, the impression is sometimes one of the “too long” left leg pushing down the foot and up the ilium so that better local organization at ankle and hip levels tends to increase the one sidedness.

In general it seems that the potential problems for left/right symmetry in the lower girdle are not very important with small differences in leg length. When they are marked, the right longer leg and the reversed left longer leg are very problematic. If one just organizes locally and “straightens out” the legs – disregarding the adaptive compensations the body already employs – the overall result is easily disintegration. The problem is as always that this is not easily recognized. For, the client feels better anyway for the increased “freedom” and smoothness after the session, and the destructive effects of disintegration only turn up in the long run when the body collapses more.

The situation in the upper body has not been examined. It is obvious that it must compensate for the pelvic side-tilt on the shorter leg by leaning toward and over the longer leg. This can be on different levels. It may be down in the lumbar segment where the trunk curves toward the side of the longer leg or as far up as the top of the thorax. Generally the upper body will be convex on the shorter leg side, concave on the side of the longer leg. That concave side appears as shorter and may lead one easily to believe that it needs length. But lengthening always implies softening of the tissue, and when the client comes back one finds with dismay that this concave side has collapsed even more. Another strategy promises to produce better results although it may seem a little paradoxical. Provided the possibilities for horizontalizing the pelvis from below have been exhausted, it is more worthwhile to organize and lengthen the already “longer” convex side. Then the concave side will also sustain a little more length. The result will not be “straight” but a lengthening of the midline of the upper body along with which goes a reduction of the convexity, its bending through on the side of the shorter leg.

This study has probably raised more questions than it has answered. It foremost shows that a much better understanding is needed of what “shortness” is structural and what is due to the “ossary factor”, the asymmetry of bones of right and left leg. Part of the problem is our lack of a functioning model for the hip joints which explains how exactly the legs “meet” the pelvis. It is not impossible that there exists a basic difference between left and right hip. The left one e.g. seems to be more “suspended down from the femur”, the right one more “riding on top of it”. There was also an observation with a client who had a homogenous right longer leg before but a reversed left longer leg after a session!(2)

It is also evident that future studies must employ independent examinators. Most important will be to observe functional modalities, i.e. to decide which kind of stance is used. And further development of the testing techniques using gravity’s effect and regarding the tensional and compressional properties of the fascial net is strongly indicated. This should eventually lead to some kind of understanding of the issue of left/right symmetry which is founded in observation of reality. Improvement of the quality of integration and a reduction of the incidence of disintegration would be the welcome consequence.


1. Left/right differentiation is notoriously difficult for the brain. Its determination is purely self-referential. i.e. one’s own body is the reference system. But its anatomical differences are small, and so it is often necessary to evoke a dominant functional pattern minimally – writing, shaking hands – which provides orientation.

2. In the extremely vague language we are forced to use in the absence of any real knowledge: the right hip was “drawn in” before but “let out” after the session.

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