by Erik Dalton PhD. “Learn to fix low-back pain and you’ll always have a full practice” A.T. Still…Father of Osteopathy, 1897 During a ten-step low back screening evaluation, therapists typically check anatomic landmarks such as anterior superior iliac spine, crest height, leg length, etc. Very commonly seen is an anterior/inferior right rotated ilium accompanied by a high left posteriorly rotated ilium. Structurally-oriented therapists are aware of the importance proper iliosacral alignment plays in avoiding compensatory low back and SI joint strain. Researchers such as Zink1, Previc2, and Geschwind3 have developed fascinating theories (motor dominance, cerebral lateralization, genetic potential, etc.) explaining possible origins of this commonly seen pattern. All agree that the architecture of the feet play a major role in pelvic positioning but other than lengthening or shortening of a limb, many in the manual therapy community are unclear about the link between foot posture and back pain. Case Study For discussion purposes, let’s suppose you’re performing an assessment with client standing. Using the finger pads of your right hand, swipe the left medial arch. With two fingers, try and lift the navicular bone. If the assessment reveals the navicular and cuneiforms have no spring and the foot appears to be flat, the arch is pronated. Recall that the most common asymmetry found in the lower extremity is foot pronation which typically results from a valgus subtalar joint (STJ) accompanied by a dropped navicular bone(Fig. 1). Moving on to the right foot you palpate a high rigid arch that feels stuck in a supinated position. In foot supination, the STJ is usually fixated in a varus position accompanied by a collapsed cuboid. This combination of foot pronation and supination not only affects leg length, but begins an ascending syndrome pattern that travels up the kinetic chain distorting knee, hip, pelvic and low back structures (Fig. 2). Since left-legged foot pronation internally rotates the thigh and a supinated right foot externally rotates the thigh, left untreated, the person would be forced to walk sideways with each step (Fig. 3). But the body’s intricate proprioceptive system won’t stand for it and immediately begins to make adjustments. The most overlooked and least understood of all the body’s compensatory patterns (in my opinion) directly results from asymmetrical placement of the femoral head in the acetabulum. Femoral Positioning and Pelvic Rotation When the pronated left foot internally rotates the left lower extremity, the femoral neck also internally rotates which pushes the femoral head posteriorly against the back of the acetabulum (Fig 4). (If possible, try this on a plastic skeleton). Conversely, right foot supination externally (right) rotates the femoral neck causing the head to push against the anterior part of the acetabulum. With the right femoral head pushing anteriorly and the left pushing posteriorly, the bony pelvis is forced to left rotate. This happens as the high femoral head “drives” the anterior portion of the pelvis upward and backward which rotates the pelvis to that side causing the pelvis to drop down on the low femoral head side. Thus, we see an unleveling of the sacral base and a buckling of the lumbar segments. During a screening evaluation, therapists often stop the assessment and begin treating the crooked iliosacral joints by lengthening the hip flexors on one side and extensors on the other to create pelvic balance. Treating locally rather seeking out the dysfunctional global patterns is, at best, a temporary “quick fix”. Simply correcting pelvic alignment is doomed to failure and will not permanently relieve the compensatory back strain if the torsioned pelvis has roots in foot dysfunction. Pronation and supination not only torsion the pelvic bowl, but can create a painful lumbar rotoscoliosis with compensations traveling through the thoracic and cervical spine (Fig. 5). Try this experiment: With fingers placed under each ASIS, pronate your left foot, supinate the right, and feel the right ASIS drop anterior/inferiorly as body weight side-shifts over the left posterior/superiorly innominate. This causes the pelvic bowl to left rotate. This mechanism of anteroposterior femoral head positioning also helps explain other clinical findings. For example, we often see clients with bilateral foot pronation (pes planus) which results in increased lumbar lordosis, lumbosacral angle and jamming of the L4-5 and L5-S1 facets. In these people, both femoral heads are positioned posteriorly which ‘dumps’ the pelvic contents forward and sways the back. Conversely, bilateral supinated (pes cavus) feet position the femoral heads anteriorly in the acetabulum causing decreased lumbar lordosis, flat back, butt and no anti-gravity spring system. Summary A prerequisite for all pain management and structural integration therapists requires a basic understanding of the relationship of iliosacral unleveling and foot posture. In the absence of radiographic measurements, therapist must develop keen palpatory and visual skills to aid in proper evaluation of bony and soft tissue landmarks. As Sir William Osler eloquently stated, “In order to treat something, we must first be able to recognize it”. Any attempt to tackle iliosacral rotational patterns armed with inadequate assessment and treatment tools will undoubtedly lead to failure and frustration. Common pelvic obliquity strain patterns must be understood and corrected before proceeding to more complex sacroiliac and lumbar spine problems although low back and SI joint dysfunction triggered by a traumatic incidence can also influence pelvic rotation and foot posture. From a functional standpoint, there is strong evidence of an associated increase in the incidence of low back pain and hip joint osteoarthritis when foot posture and femoral rotational patterns are not corrected in a timely manner. This article is from the Myokskeletal E-technique newsletter. Click here to subscribe References Zink G J. AN Osteopathic Structural Examination of the Soma. Osteopathic Annals 7:12-19, 1979 Previc F. A General Theory Concerning the Prenatal Origins of Cerebral Lateralizations in Humans. Psychological Review. Volume 98, 1991 Geschwind N. Cerebral Lateralization. MIT Press, 1987 Original article and pictures take http://erikdalton.com/low-back-pain-foot-posture/ site
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