Pelvis Aligned, Legs Length Equal

All the pelvic landmarks are level with their counterpart on the left in standing, sitting, and lying. The right and left ASIS and PSIS are equidistant from the midline (see Fig. 14 Aii, Bii). The malleoli lie at the same level and move together, downward on sitting up and upward on lying down.

Pelvis Aligned, Right Anatomic (True) Leg Length Difference Present

Compared with the left side, the right iliac crest and all other right pelvic landmarks are higher in standing but are level and equidistant from midline when sitting and lying ( Fig. 17 ). The right malleolus will appear to be displaced downward relative to the left one by the same amount in both sitting and lying (reflective of the true leg length difference) and the legs move together on changing from one position to the other.

Pelvic obliquity with the belt and iliac crest angled up on the right side; compensatory scoliosis and downward displacement of left shoulder and arm; head remains centered and level. Findings could be in keeping with true leg length discrepancy (right leg long), upslip or rotational malalignment.

Examination Findings

• 1.
  

  Flaring of 1 or both innominates is the second most frequently seen of the 3 most common presentations of pelvic malalignment, noted in 40% to 50% altogether.

  
  
• 2.
  

  The right or left innominate becomes fixed in excessive outward or inward rotation in the horizontal plane. The contralateral innominate, although it may be found to lie in its normal position, is usually fixed flared in the opposite direction, as if to compensate. With a right outflare and left inflare:

  
  
  
  
  • a.
    

    The right ASIS will have moved away from the midline of the abdomen, the left toward it (see Fig. 14 Ai). Findings are the reverse for the PSIS: the left toward, the right away from midline, demarcated by the gluteal cleft and spinous processes (see Fig. 14 Bi).

    
    
  • b.
    

    The left ASIS ends up moved forward with the inflare, the right backward with the outflare (see Fig. 7 iii). As a result, the left one seems to be:

    
    
    
    
    • i.
      

      Protruded forward in standing and sitting compared with the right and

      
      
    • ii.
      

      Displaced upward (ie, h i gher) and the right downward (ie, l O wer) when observed with the runner lying supine ( Fig. 18 ).

      
      

      
      

      
      

      
      

      
      

      Right outflare, left inflare. ( A , B ) A spirit level resting on top of the right and left anterior superior iliac spine (ASIS) shows elevation of the left side. ( B ) Feet (clamps) attached to the level rest on the ASIS; they help to raise the bubble into view (eg, for someone who is obese, pregnant). ( C ) ASIS now level, bubble in center, after correction of the outflare/inflare (same subject as in A ).

      
      

    
    
    
    
  • c.
    

    Barring a coexisting true leg length difference, the landmarks are level in the frontal plane in all positions and leg length is equal in sitting and lying.

    
    
  • d.
    

    Radiographs show the changes in the landmarks observed ( Fig. 19 ).

    
    

    
    

    
    

    
    

    
    

    Radiographic changes seen with a left outflare, right inflare. ( A ) Anteroposterior projection of pelvis and hip joints. The femoral heads remain at the same level as the left acetabulum moves outward and the right inward in the horizontal plane. Innominate width seems to be increased on the left and decreased on the right. The anterior superior iliac spine looks to be increased in overall size and broader on the outflare ( left ) side and smaller and narrower on the inflare ( right ) side. The left femoral neck lies further away from and the right one closer to the ipsilateral inferior pubic ramus. The left lesser trochanter (LT) seems to be smaller as a result of overlapping occurring with passive external rotation of the femur; on the right it seems to be larger, having been brought into view with internal rotation of that femur (see also Fig. 10 ). ( B ) Diagrammatic conceptualization of the AP beam projection onto the pelvis when aligned and with a left outflare, right inflare present; superoinferior view.

    
    

  
  

Diagnosis and Corrective Procedures: Right Outflare, Left Inflare

When a right outflare, left inflare is present, on lying supine:

• 1.
  

  The right ASIS is l O wer and displaced O utward, away from midline.

Remember the mnemonic of the 4 O s:

The treatment method referred to here is a form of manual therapy, known as the muscle energy technique (MET). It gets the runner to harness the energy in muscles that are positioned in a way that enables them to effect the specific change. In this case, resisting abduction and external rotation of the femur by blocking outward movement of the partially flexed right knee ( Fig. 20 ) reverses the origin and insertion of the right piriformis and gluteus maximus (see Figs. 2 and 3 ). These muscles can act on the innominate (which is still free to move) to rotate it forward in the horizontal plane until it again comes to lie in its normal position relative to the sacrum. The repeated contraction–relaxation of these muscles also can decrease tone and increase muscle relaxation and lengthening that, together, make it easier for the bones to slot back into their proper place.

• 2.
  

  The left ASIS is h i gher and displaced i nward, toward the midline.

Using muscle energy technique (MET) to correct a right outflare: resist active right thigh abduction and external rotation; that is, block outward movement of flexed right knee. ( A ) One-person, sitting (or lying) approach. ( B ) A 2-person approach is easy to carry out with subject lying supine, ipsilateral hip and knee flexed and foot resting on bed.

Remember the mnemonic of the 4 I s:

Blocking adduction of the left leg reverses the origin and insertion of the left gracilis and adductor longus ( Fig. 21 ; see Fig. 55 ). The force generated is now directed to their attachment onto the left pubic tubercle and is capable of rotating the innominate outward, back into alignment ( Fig. 22 ).

Neurovascular structures at risk of compromise within the femoral triangle by any increase in tension, particularly in iliacus, psoas and pectineus. ( Note: adductor longus origin from pubic tubercle [see Fig. 22 ], also lateral femoral cutaneous nerve traversing the canal).

( From Schamberger W. The malalignment syndrome: Diagnosing and treating a common cause of acute and chronic pelvic, limb and back pain. Edinburgh (UK): Churchill Livingstone; 2013. Adapted from Anderson JE. Grant’s atlas of anatomy, 7th edition. Baltimore: Williams and Wilkins, 1980.)

To correct a left inflare, resist active left thigh adduction and internal rotation; that is, block inward movement of flexed knee. ( A ) One-person lying (or sitting) approach. ( B ) Two-person approach ( note: arrow on left inner thigh denotes direction of adductor longus pull on right pubic tubercle attachment to rotate innominate outward).

Clinical Correlation for Runners

• 1.
  

  An outflare strains the anterior SI joint ligaments/capsule and compresses the posterior joint margins; an inflare has the opposite effect (see Figs. 1 , 2 , 7 iii, and 19 B). There may be discomfort from the structures put under stress.

  
  
• 2.
  

  With a right inflare, left outflare, the left acetabulum faces progressively more posterolaterally as that innominate rotates outward (see Fig. 19 A). The left superior rim comes to lie more directly anterior to the femoral head with the outward rotation of that innominate, sometimes to the point that the femoral head actually impinges against the rim as the hip joint is increasingly flexed going through swing phase. Compared with the ease with which the right leg moves through this phase:

  
  
  
  
  • a.
    

    The runner may literally sense the block to this motion occurring on the left side and there may be discomfort or pain with impingement of the acetabular rim, felt in the left groin and/or hip region.

    
    
  • b.
    

    Left swing-through is limited. To compensate, he or she can:

    
    
    
    
    • i.
      

      Bring the acetabulum facing further forward by actively increasing the extent that the pelvic ring as a whole rotates clockwise during left swing phase, partly effected by increasing active clockwise rotation of the trunk and changing the movement pattern of the arms, in an attempt to match right stride length; and

      
      
    • ii.
      

      Cut back the degree of right swing-through to match that on the left and, instead, increase stride frequency to maintain the same speed.

    
    

  
  

Either compensation method leads to unwanted changes in the gait pattern that can prove costly in terms of decreased efficiency and increased energy demands.

Examination Findings

Innominate rotation is the most frequently seen of the 3 common presentations of pelvic malalignment, noted in 80% to 85% altogether. An innominate can become fixed relative to the sacroiliac joint, in a position of excessive rotation in the sagittal plane, either forward (anterior) or backward (posterior). Usually, but not necessarily, the contralateral innominate is fixed in rotation in the opposite direction. Some 80% to 85% thus affected have a right anterior, left posterior and 15% to 20% a left anterior, right posterior rotation. The SI joint may be locked on one side so that on the kinetic rotational (Gillet) test the innominate and adjoining sacrum on the locked side move as 1 unit, upward on progressive hip flexion, downward on hip extension, which is opposite to what happens normally ( Fig. 23 ).

Abnormal right kinetic rotational (Gillet) test, with right sacroiliac joint locked. ( A ) On initial right hip flexion to horizontal: right thumb (which marks the location of right posterior superior iliac spine [PSIS]) fails to drop down relative to the left one (marking the sacral base). ( B ) On increasing right hip flexion: the right thumb (PSIS) actually moves upward. The sacrum and PSIS are moving together as 1 locked unit, counterclockwise in the frontal plane.

Diagnosing Rotational Malalignment

With a right anterior, left posterior rotation (see Fig. 13 ; Fig. 24 ):

• 1.
  

  All the anterior and posterior landmarks are displaced asymmetrically on both side-to-side and front-to-back comparison. For example:

  
  
  
  
  • a.
    

    The right ASIS ends up lower compared with the ipsilateral PSIS and the left ASIS; and

    
    
  • b.
    

    The right pubic ramus is displaced downward and rotated forward in the sagittal plane; the left undergoes displacement in the opposite directions.

  
  
  
  
• 2.
  

  There is a pelvic obliquity, with the right iliac crest and ischial tuberosity ending up higher relative to left side (see Figs. 13 and 17 ).

  
  
• 3.
  

  There is an apparent leg length difference noted in the sitting–lying test. Which leg seems to be longer or shorter is of little importance. What matters is that there is a shift in leg length on this test, with the right malleolus moving upward in sitting up and downward on lying down relative to the left (see Figs. 15 and 16 ; Fig. 25 ). This shift is characteristic of a right anterior, left posterior rotation; it would be in the opposite direction with a left anterior, right posterior rotation.

  
  

  
  

  
  

  
  

  
  

  Sitting–lying test: rotational malalignment presentation. All 3 subjects have right anterior, left posterior innominate rotation, with relative lengthening of the right leg compared with the left on moving from long sitting to supine lying. ( A ) The right leg is shorter sitting, longer lying; this is the most common pattern. ( B ) The right leg is shorter sitting but less so in lying. ( C ) The right leg is longer sitting and even more so in lying.

  
  
  
  
• 4.
  

  Remember the mnemonic of the 5 L s to help determine the side of an anterior rotation:

Typical pelvic distortion associated with rotational malalignment: right anterior, left posterior rotation, as shown. Pubic bones are rotated and displaced relative to each other at the symphysis; sacrum in torsion around the left oblique axis. Pelvic obliquity (shown inclined to right ) and compensatory scoliosis (thoracic segment convex to right, lumbar convex to left, with L1-4 rotated into the convexity).

In the case of a right anterior, left posterior rotation, the right anterior landmarks end up lower relative to those on the left and the right leg lengthens on lying down.

• 5.
  

  Radiographs show the changes in the landmarks observed ( Fig. 26 ).

  
  

  
  

  
  

  
  

  
  

  Radiographic changes with malalignment: the effect on sacroiliac and facet joint orientation to the anteroposterior beam. The L1-L4 vertebral rotation into the left convexity (ie, counterclockwise) opens up the left midlumbar facet joints and accentuates the closing/compression of the right facet joints that results with the simultaneous left rotation and right side-flexion of the vertebrae. The right sacroiliac joint seems to be open along its full length, whereas only the midsection of the left one is visible as a result of overlapping and reorientation of the joint surfaces relative to the beam and to the right side (see also Figs. 10 and 19 ). L5 is sacralized on the left.

  
  

Corrective Procedures for Rotational Malalignment

There are a number of different manual therapy techniques that can be used to correct a rotational malalignment. However, MET, leverage, or a combination of the 2 techniques can be useful in that they may allow the runner to correct a recurrence between visits to the therapist or even when on the track or out on the road ( Figs. 27–34 and 37 ). In the case of a:

• 1.
  

  Right anterior rotation:

  
  
  
  
  • a.
    

    Blocking movement of the right thigh away from the trunk (ie, right hip extension) activates right gluteus maximus ( Figs. 30 and 31 ). Reversal of its origin and insertion allows it to rotate the right innominate in a posterior direction, by way of its attachments to the posterosuperior aspect of the ilium (see Fig. 2 B).

    
    
  • b.
    

    Passively moving the right femur into increasing flexion to the point where the femoral head impinges against the anterior rim of the acetabulum creates leverage and simultaneously tightens some posterior structures, including the sacrotuberous ligament. The combined effect is a posterior rotational force on the right innominate (see Fig. 27 A).

  
  
  
  
• 2.
  

  Left posterior rotation:

  
  
  
  
  • a.
    

    Blocking movement the left thigh toward the trunk (ie, left hip flexion) activates left iliacus ( Figs. 32 and 33 ) and rectus femoris (see Fig. 28 B); the latter also responds to blocking extension of the flexed knee (see Fig. 28 A; Fig. 34 ). The muscles then exert an anterior rotational force by way of their attachments to the anterosuperior part of the ilium and to the pubic bone, respectively (see Fig. 3 ).

    
    
  • b.
    

    Passively extending the femur to the point where the femoral head impinges on the posterior acetabular rim turns the femur into a lever capable of creating an anterior rotational force on the left innominate (see Fig. 27 B).

  
  

Using a leverage effect to correct rotational malalignment. ( A ) Passive hip flexion to counteract a right anterior rotation: (i) 1-person and (ii) 2-person techniques. ( B ) Passive hip extension to counteract a left posterior rotation: (i) 1-person and (ii) 2-person techniques.

One-person muscle energy technique to correct a left posterior rotation by activating rectus femoris with the left knee ( A ) in flexion, ( B ) in extension. ( C ) Rectus femoris action in standing.

Leverage effect of the femur on the innominate, by impingement against the acetabular rim (see also Fig. 27 ). Correction of ( A ) an anterior rotation; ( B ) a posterior rotation.

One-person muscle energy technique to correct an anterior rotation: using the gluteus maximus to create a posterior rotational force on the innominate.

Two-person muscle energy technique using the gluteus maximus to correct a right anterior rotation.

One-person muscle energy technique using iliacus to correct a left posterior rotation.

Two-person muscle energy technique using iliacus to correct a left posterior rotation.

Two-person muscle energy technique using the rectus femoris to correct a left posterior rotation. Having the runner’s ankle/distal part of the lower leg propped up under the armpit (or lying on top of the shoulder; not shown) allows the assistant to use his body weight to advantage to generate the counterforce needed to block knee extension.

Clinical Correlation for Runners

• 1.
  

  Runners should be discouraged from routinely doing excessive unilateral stretches of iliopsoas, rectus femoris, gluteal muscles, and hamstrings, especially when the pelvis is free to move, as in standing ( Fig. 35 ). For example, a right iliopsoas/quadriceps stretch tightens up right iliacus and rectus femoris; the femur may also end up far enough in extension to exert a leverage effect (see Fig. 35 A). This maneuver is capable of:

  
  
  
  
  • a.
    

    Forcing the right innominate to go out of alignment so it ends up fixed in an anterior rotated position; and

    
    
  • b.
    

    Undoing any realignment that has been achieved, because it can literally force the innominate back out of alignment again.

  
  

  
  

  
  

  
  

  
  

  ( A ) Popular unilateral quadriceps stretch that can cause or aggravate a preexisting right anterior rotation, by way of (1) rectus femoris pulling on its innominate origin and/or (2) the femur coming to act as a lever with increasing hip extension. ( B ) Unilateral hamstrings stretch (eg, straight leg propped up on a chair or table) can have a similar deleterious effect by causing/aggravating a posterior rotation. However, this same maneuver may be able to correct a preexisting right anterior rotation (see also Fig. 37 ).

  
  
  
  
• 2.
  

  To decrease this risk, stretches are best carried out simultaneously on both sides, preferably with the pelvis stabilized; for example, bilateral hamstring stretch: sitting on the floor, legs out in front; quadriceps, iliopsoas and pectineus: leaning the pelvis and trunk backward while kneeling ( Fig. 36 ).

  
  

  
  

  
  

  
  

  
  

  Simultaneous, symmetric stretch of bilateral quadriceps, iliopsoas, and pectineus (see Figs. 3 B, C and 19 ) carried out by subject kneeling and gently leaning backward.

  
  
  
  
• 3.
  

  However, unilateral leverage maneuvers can actually be used effectively by the runner on the side of a known rotation. For example, a right anterior rotation may respond to placing the right foot on a chair and gradually leaning forward with the trunk, arms dangling downward ( Fig. 37 ). The same may be accomplished by having the right foot up on a ledge and leaning forward (see Fig. 35 B). The progressive increase in passive hip flexion turns the femur into a lever capable of correcting the rotation.

  
  

  
  

  
  

  
  

  
  

  A right anterior rotation may be corrected by resting the right foot on a raised surface and simply letting the trunk hang down in forward flexion as far as is comfortable. With increasing right hip flexion, the femur can eventually exert a leverage effect, with posterior rotation of the innominate (see also Fig. 35 B). Bouncing or straining while reaching down must be avoided because it can precipitate or aggravate pain and muscle spasm.

  
  
  
  
• 4.
  

  Unilateral stretches of a specific muscle may be indicated following realignment for:

  
  
  
  
  • a.
    

    Muscles that have undergone contracture while in a shortened state during the time that malalignment was present; and

    
    
  • b.
    

    Ones that fail to relax completely, show increased tone, or are actually in spasm.

  
  

Examination Findings

Of the 3 most common presentations of pelvic malalignment, an upslip is the least frequently seen, appearing in isolation in 10% and in combination with a flare, rotational malalignment, or both in another 10%. The innominate on 1 side ends up displaced straight upward relative to the adjacent sacrum and becomes fixed in that position. Again, although often no cause may be evident, some obvious ones include:

• 1.
  

  Having the force of an impact transmitted straight upward, either through:

  
  
  
  
  • a.
    

    One extremity: for example, missing a step (see Fig. 12 A); landing hard on 1 leg when jumping or running downhill with the knee in extension ( Fig. 38 ) or

    
    

    
    

    
    

    
    

    
    

    Right upslip caused by a unilateral upward force on the femur transmitted through the hip joint to the innominate. ASIS, anterior superior iliac spine; PSIS, posterior superior iliac spine.

    
    
    
    
  • b.
    

    The innominate itself; for example, falling directly onto an ischial tuberosity (see Fig. 11 B).

  
  
  
  
• 2.
  

  An upward traction force being applied to the innominate; for example, with a chronic increase in tension or spasm in quadratus lumborum, psoas major/minor ( Fig. 39 ).

  
  

  
  

  
  

  
  

  
  

  Muscles capable of generating forces ( arrows ) that can result in an upslip.

  
  

As a result, on the side of the upslip one finds:

• 1.
  

  The anterior and posterior pelvic landmarks are all displaced upward relative to those of the opposite innominate and to the sacrum.

  
  
• 2.
  

  The ipsilateral leg is moved upward passively with the innominate, creating an apparent leg length difference. Relative to the opposite leg, it seems shortened to the same extent in both sitting and lying and the malleolus moves downward and upward, respectively, together with that on the other side ( Fig. 40 ).

  
  

  
  

  
  

  
  

  
  

  Sitting–lying test: right sacroiliac joint upslip. The legs move together and the right leg remains short to the same extent in sitting and lying. The right anterior and posterior pelvic landmarks are all displaced upward relative to the sacrum and left innominate. ASIS, anterior superior iliac spine.

  
  
  
  
• 3.
  

  A pelvic obliquity is evident in standing, sitting, and lying.

Corrective Procedures for an Upslip

With the runner lying supine, applying gentle, repetitive traction to the leg on the upslip side usually suffices, often simply by helping to relax tense muscles around the hip/pelvic girdle that are holding the innominate in the upslip position (see Fig. 39 ; Fig. 41 ). If that fails to achieve correction, manipulation using a quick downward pull on the leg once or twice may prove successful. The runner can be instructed in self-correction (see Fig. 41 B):

• 1.
  

  Starting by simply letting that leg hang down while standing on a step or stool, and

  
  
• 2.
  

  Progressively increasing either the time it is suspended or the amount of a weight attached, usually 20 to 30 minutes using 2.5 to 4.5 kg proves effective.

Correction of a right upslip. ( A ) Two-person technique. ( B ) One-person: using the weight of the leg (with or without extra weight attached) to exert a downward traction force on the innominate and releasing tension in muscles that may be perpetuating the upslip (see Fig. 39 ).

Clinical Correlation for Runners

• 1.
  

  The apparent leg length difference, pelvic obliquity, and compensatory scoliosis combined result in unwanted stress points, change in style, and compensatory measures; for example, leaning into the weight-bearing low side to help clear the long leg for swing-through and adjustments for side-to-side differences in stride length.

  
  
• 2.
  

  Dysfunction of the SI joint on the side of the upslip increasing stress on the other parts of the lumbo–pelvic–hip complex bilaterally.

  
  
• 3.
  

  A coexisting rotational malalignment can hide an upslip; hence, it is important to recheck alignment after correction of the rotation.

  
  
• 4.
  

  A caution: keep the rare downslip in mind.

When dealing with a supposed upslip that fails to respond to treatment, including repeated downward traction, consider the possibility that the runner has actually sustained a downslip of the contralateral innominate. For example, a traction force on one of the lower extremities that is strong enough to pull the innominate into a downslip position can occur when the runner:

• 1.
  

  Has to pull upward on a straight leg, often unexpectedly and in midstride, to extract a foot that got stuck in deep mud;

  
  
• 2.
  

  Is thrown forward, off the bike, during the cycling part of a biathlon or triathlon while 1 foot is still caught up in the stirrup.

Pelvic Ring Distortion

Displacement of the pelvic ring results in abnormal stresses on all of the joints of the lumbo–pelvic–hip complex, particularly on the adjoining surfaces of the joints and their capsule and supportive ligaments. The distortion also causes:

• 1.
  

  Disturbance of the normal transfer of weight through this complex (see Fig. 4 ) ;

  
  
• 2.
  

  Irritation of neural receptors lying within any of the structures put under stress, which can result in localized and/or referred pain and paresthesias (see Case History: Runner A, below);

  
  
• 3.
  

  Accelerated degeneration of any sites in the lower extremities, pelvis and spine put under increased stress as a result; in particular, the discs and facet joints in the lower lumbosacral region (see Figs. 10 and 26 ; Figs. 42 and 43 ) ; and

  
  

  
  

  
  

  
  

  
  

  Effect of a malalignment-related shift toward right pronation, left supination on the knee. ( A ) Right side: the tendency toward pronation and knee valgus angulation increases the Q-angle and the pressure on the lateral compartment; excessive pronation can result in a forceful upward movement of the fibula and a jamming of the proximal tibiofibular joint (similar to what can occur with an ankle eversion sprain). ( B ) Left side: the tendency toward supination and knee varus angulation decreases the Q-angle and increases pressure on the medial compartment.

  
  

  
  

  
  

  
  

  
  

  Osteoarthritic changes in the knee as a result of long-term pressure redistribution similar to what can occur with a malalignment-related shift in weight bearing: accentuated wear of right lateral and left medial joint compartments (see Figs. 49 and 50 ).

  
  
  
  
• 4.
  

  Pelvic obliquity and an apparent leg length difference.

Compensatory Curves of the Spine

The pelvic obliquity results in a compensatory scoliosis—curves in the frontal plane—to ensure the head ends up in midline as best as possible, with the eyes and ears level, to minimize any disturbance of visual function and the labyrinthine balancing mechanisms.