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Can Early Correction Of Hyperpronation Help Prevent Secondary Deformities?
Offering a closer look at the literature on pediatric hyperpronation, this author emphasizes the importance of early treatment to prevent potential long-term effects of this abnormality.
When the foundation of a building is unstable, it throws everything else out of alignment. It may cause structural damage to the floors, walls or plumbing, or even cause a total collapse of the structure.1 Therefore, it should come as no surprise that when there is misalignment of the body's foundation joint, the subtalar joint, it may have a significant impact on other parts of the body, specifically, the knees, hips and lower back.2
Proper balance depends on a stable talotarsal joint. Instability at this joint interrupts uniform weight distribution and impacts gait. This places additional stress on proximal structures, particularly the knee, pelvis and spine, as they work to support the dysfunctional talotarsal joint.3 Additionally, ligaments, tendons, muscles, and joints experience added strain, which often leads to lifelong pain. This cascade all starts with overpronation at the subtalar joint.
Joint Movement In Normal Gait: What You Should Know
The subtalar and transverse tarsal joints are crucial to a normal gait with the transverse tarsal joint relying heavily on healthy function in the subtalar joint.
Throughout the movement of the foot during walking, from heel strike through the pronatory stages, heel rise and toe off, the structures of the foot constantly move and shift to absorb the shock of the body's weight and propel the body forward.4 During the heel rise stage in particular, the foot absorbs two to three times the body's weight. These forces are doubled when one is running and may be tripled in a sprint.4
The bones, joints, muscles and ligaments of the lower skeleton support the foot when walking or running, with the primary function being to stabilize the foot during gait. However, in an abnormal gait, lower musculoskeletal tissues face greater strain.
Pertinent Insights On Gait Abnormalities With Pediatric Flat Feet
Most children experience some degree of flatfoot during early development. However, a calcaneal misalignment of four degrees or more once the child reaches age six to seven years of age indicates a potentially significant problem requiring treatment.5
When it comes to a child with overpronation, there is hypermobility throughout the gait cycle. The foot joints typically remain unlocked throughout the stance phase of walking and fail to become rigid during the heel rise and toe off stages of propulsion.5
While in hyperpronation, the child's lower extremities must work harder to stabilize the foot, placing additional strain on the joints, muscles and other tissues. Imagine the feeling of walking on unstable terrain, such as a sandy beach, and the greater degree to which your body engages the knees, hips and back. This mimics the experience of walking with pediatric flatfoot, causing fatigue and decreased endurance. It is why, for many children, the early signs of hyperpronation include not wanting to run or participate in physical activities that their peers enjoy.
Key Considerations With Correcting Hyperpronation In Children
By the time one turns 45 years of age, the average person will take around 80 million steps.2 Researchers found that, even when gait abnormalities were minor, the compounded action of the millions of steps taken over a lifetime leads to significant, chronic issues in the knee, back and hips.2 Around 80 percent of the symptoms caused by excessive hyperpronation manifest in the knees, hips and lower back.2 Addressing hyperpronation at a younger age can greatly reduce the damage that occurs over time.
Talotarsal joint instability has been linked to medial knee compartment pathology with promising studies revealing the positive effect of extraosseous talotarsal stabilization in preventing and treating osteoarthritis and chronic knee pain.2 Correcting the talotarsal joint dislocation could lead to less recurrent knee problems and help reduce the need for invasive surgeries later in life.2
A variety of studies on runners with overpronation have found they are more likely to experience "excessive internal rotation of the shank with excessive anterior pelvic tilt."6 As with chronic knee pain, researchers believe that the repetitive stress of walking on a pronated foot causes the leg to rotate inward while in motion. In turn, the knee joint may become unaligned, causing bursitis or arthritis in the hip.6
Studies reveal that foot posture (i.e. flat feet) relates directly to the spine. In particular, the cumulative stress of an abnormal gait over decades contributes to back pain due to lumbar curvature and thoracic kyphosis.7,8
Correcting hyperpronation early (before the child has grown and taken tens of millions of steps) can help prevent chronic knee, hip and back pain in adulthood. For example, the performance of extraosseous talotarsal stabilization in adults, using the HyProCure® II stent (GraMedica) showed a 32.8 percent reduction in forces on the medial knee joint.2 These results support treating people earlier rather than later in life.
In Conclusion
Flat feet in children can be an extremely normal developmental phase with the condition typically resolving by the time the child reaches school age. However, a significant number of children with flat feet continue to experience hyperpronation. One should observe fairly neutral foot alignment by age six or seven, after which, four degrees or more of calcaneal deviation from vertical warrants clinical attention.5 Some of the warning signs include tiring more quickly and being more prone to shin splints, Achilles tendinitis, and other overuse injuries.5
Extraosseous talotarsal stabilization with HyProCure is a viable, minimally invasive option in comparison to traditional surgical techniques. With a 94 percent success rate, it offers an ideal solution when conservative treatment fails.9 I find the patient can typically bear weight the day of the surgery with a return to normal footwear within two weeks and resumption of normal activities by eight weeks. In my experience, when performing the procedure during childhood, the stent rarely necessitates replacement or removal in adulthood and can lead to a decrease in secondary orthopedic deformities later on in life.
Dr. Jarman is a member of the American Podiatric Medical Association and the American College of Foot and Ankle Pediatrics. He operates two private practices, Preferred Foot & Ankle and Pediatric Foot & Ankle, in Gilbert, Arizona.
1. Cooper AH. The classification, recording, databasing and use of information about building damage caused by subsidence and landslides. Quarterly J Engineering Geology Hydrogeology. 2008:41(3): 409-424. 10.1144/1470-9236/07-223.
2. Kolodziej L, Summers RK, Graham ME. The effect of extra-osseous talotarsal stabilization (EOTTS) to reduce medial knee compartment forces – an in vivo study. PLoS ONE. 2019;14(12):e0224694.
3. HyProCure. What does it fix?. Available at: https://www.hyprocure.com/what-does-it-fix/ . Accessed February 23, 2021.
4. Greisberg J. Biomechanics of Walking. Foot Education. Available at: https://footeducation.com/biomechanics-of-walking-gait/ . Published March 3, 2019. Accessed February 23, 2021.
5. DeCaro LJ. Gait analysis in pediatric patients with flatfoot. Podiatry Today. 2013;26(2):50-54.
6. Riskowski JL, Dufour AB, Hagedorn TJ, Hillstrom HJ, Casey VA, Hannan MT. Associations of foot posture and function to lower extremity pain: results from a population-based foot study. Arthritis Care Res (Hoboken). 2013;65(11):1804-1812.
7. dos Santos Borges C, Fernandes LF, Bertoncello D. Relationship between lumbar changes and modifications in the plantar arch in women with low back pain. Acta Ortop Bras. 2013;21(3):135-138.
8. Ghasemi MS, Koohpayehzadeh J, Kadkhodaei H, Ehsani AA. The effect of foot hyperpronation on spine alignment in standing position. Med J Islam Repub Iran. 2016;30:466.
9. Graham ME, Jawrani NT, Chikka A. Extra-osseous talotarsal stabilization using HyProCure® in adults: a 5-year retrospective follow-up. J Foot Ankle Surg. 2012;51(1):23-29.
