Fixing Achy Hips
By Erik Dalton, PhD
Structurally oriented therapists are keenly aware of the crucial role proper iliosacral alignment plays in preventing compensatory low back and SI joint pain. During the 10-step screening evaluation, therapists usually compare anatomical landmarks such as anterior and posterior superior iliac spines and iliac crests.
A commonly observed pattern reveals an anterior/inferior right rotated ilium accompanied by a high left posterior rotated ilium. Scientists have developed fascinating theories (motor dominance, cerebral lateralization and genetic potential) to shed light on the possible origins of these frequently seen patterns.1-6 Although most manual therapy clinicians agree that the foot's architecture plays a major role in iliosacral rotation, many remain unsure of the link between foot posture, pelvic obliquity and hip/back pain (aside from lengthening or shortening of a limb).
For demo purposes, let's "mock-up" a postural foot assessment with the client standing. Using the finger pads of your right hand, palpate the medial arch of the left foot. Contact the navicular bone and with two fingers, attempt to lift the arch, checking for joint play. (Fig. 1) If the navicular and cuneiforms resist this spring test and the mid-foot appears flat, the arch is pronated. As we recall, the most common lower-extremity asymmetry is foot pronation. Weakness of tibialis anterior, peroneus longus and the plantar aponeurosis (Stirrup Spring System) results in a valgus subtalar joint (STJ) accompanied by a dropped navicular bone. (Fig. 2)
Femoral Positioning & Pelvic Rotation
In my experience, the most overlooked and least appreciated area of compensation arises as the femoral heads become asymmetrically positioned in the acetabula. For example, when the pronated left foot internally rotates the thigh and the supinated right foot externally rotates the thigh, one would be walking sideways with each step. (Fig. 4) Of course, the body's sensitive proprioceptors immediately begin left-rotating the trunk with the axis of rotation primarily focused at the hips. As the femoral heads reposition in the acetabula, a great amount of stress is placed on the joint capsules, articular cartilages and supporting ligaments.
Figure 3
Use a plastic skeleton and pronate the left foot noticing how it internally rotates the left lower extremity, causing the femoral neck to follow. This closed-chain movement crams the femoral head posteriorly against the back of the acetabulum. (Fig. 5) Conversely, supination of the right foot externally (right) rotates the femoral neck allowing the head to migrate into 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. In this scenario, the high (left) femoral head becomes the axis of rotation as it drives the anterior portion of the pelvis upward and backward, causing the pelvis to rotate to that side. Thus, the right ilium reacts by dropping on the low femoral head side, resulting in an unleveling of the sacral base and a buckling of the lumbar segments.
This mechanism of anteroposterior femoral head positioning also helps explain other clinical findings. For example, we often have clients presenting with bilateral foot pronation (pes planus) complain of back pain. Bilateral pronation increases lumbar lordosis and lumbosacral angle, causing excessive compressive force through the L4-5 and L5-S1 facets and intervertebral discs. With these individuals, both femoral heads are positioned posteriorly allowing the pelvic contents to "dump" forward and sway the back. Conversely, bilateral supinated feet position the femoral heads anteriorly in the acetabula resulting in decreased lumbar lordosis, flat back, flat butt and loss of kinetic energy into the ground during gait. Although various aberrant combinations of femoral positioning exist, some are considerably more detrimental than others.
Femoral Positioning & Hip Impingement
Orthopedists theorize FAI could serve as a major cause of damaged hip joints in adults and the primary reason behind the escalation of hip replacements. Treating FAI impingement should involve techniques for balancing femoral head/neck positioning relative to the acetabulum. Since FAI arises from bony or mechanical abnormalities of femoral head placement in the acetabulum, manual therapists often have the best shot in preventing or correcting this anomaly and would benefit greatly by attending workshops designed to assess and treat this pervasive condition.
A prerequisite need for all pain management, sports, and structural integration therapists should involve a basic understanding of the relationship of iliosacral unleveling and foot posture. Since most therapists are not privy to radiographic measurements, we must develop keen palpatory and visual skills to properly evaluate 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 end in failure and frustration. From a functional standpoint, there is strong evidence of an associated increase in the incidence of low back pain and hip joint osteoarthritis if foot posture and femoral rotational patterns are not addressed in a timely manner.
In my next column, I'll present theories on why we encounter common compensatory patterns; discuss cerebral lateralization and motor dominance, and share myoskeletal techniques to address the strain patterns falling within the FAI realm.
References
- Zink GJ. An osteopathic structural examination of the soma. Osteopath Ann 1979;7:12-9.
- Previc F. A general theory concerning the prenatal origins of cerebral lateralizations in humans. Psychologic Rev 1991;98.
- Geschwind N. Cerebral Lateralization. Cambridge, Mass.: MIT Press, 1987.
- Rogers LJ, Zucca P, Vallortigara G. Advantages of having a lateralized brain. Proc Biol Sci2004 Dec 7;271(Suppl 6):S420-2.
- Vallortigara G, et al. Cerebral lateralization. Behav Brain Sci 2005:4.
- Tommasi L. Mechanisms and functions of brain and behavioral asymmetries. Philos Trans R Soc Lond B Biol Sci 2009 April 12;364(1519):855-859.
- Dalton E. Don't Get Married, Part 1 Massage Today, February 2008;8(2).
- Ganz R. Femoral acetabular impingement. Presented at the 15th Combined Open Meeting of the Hip Society and American Association of Hip and Knee Surgeons. Feb. 28, 2008. Las Vegas.
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