Understanding Foot Types and Managing the Adolescent Athlete

Management of the Adolescent Athlete by Foot Type

By Roberta Nole, MA, PT, C.Ped

One of the most commonly injured parts of the body in adolescents is the foot and ankle, particularly those involved in sports. Consider demographics: More than 2.6 million children are treated in the emergency department each year for sports and recreational-related injuries; over 30 Million kids are involved in at least one interscholastic sports program; 21.5 Million kids are playing on one or more organized sports teams! Therefore it is prudent to understand how functional foot types may predispose athletes to particular conditions and risk of injury. This article will review 6 functional foot types, in relation to structure and functional gait, common injuries to each, sport risk concerns, and physical management including orthotic recommendations.

Toddlers begin walking around 12-14 months. At the age of 2-3yo it is quite common for the child’s foot to be pronated, but by the age of 6-8yo the heel should be assuming a vertical alignment in standing. By 9-13yo the foot will be attaining its adult form and ideally assume an inverted heel alignment of about 4-5 degrees. It is important for the Pedorthist to understand that children are not merely “mini-adults”, and consideration needs to be given to the physical plates and growth.

The long bones in the legs and arms grow from an area at either end called the physis, or growth plate. When a child’s bones have completed growing, the growth plates ossify and cause the epiphysis to fuse together with the metaphysis, forming one complete bone. Skeletal maturity is typically reached in girls around the ages of 13-15, while boys’ growth plates close around the ages of 15-17. Around the ages of 13-15 the child’s foot will begin to evolve into its adult form, most often mirroring the foot type of Mom or Dad. Particular attention needs to be paid to young athletes complaining of pain, since the growth plates are susceptible to fracture.

Functional Foot Groups:

There are 6 functional foot groups (called “Quads”) that present themselves as a child’s foot matures into adult form. Foot type is identified by simply observing how arch height couples with forefoot “toe-sign”. Each Quad produces a distinctive gait pattern. The characteristics each Quad is summarized below along with a list of potential injuries relative to gait style and sports.

toe sign webs

A QUAD:

Foot Morphology: The “A-Quad” has an uncompensated (supinated) rearfoot combined with a forefoot valgus, resulting in a combined foot condition referred to as “torque foot”. This is a Pes Cavus foot with and inverted heel and an adducted forefoot.

Gait: STJ pronation is restricted during contact phase resulting in a rigid midfoot with high impact and shock. Upon foot flat, the 1st ray loads prematurely driving the foot and ankle into increased supination throughout propulsion. The resultant gait is a rectilinear pattern with a narrow base of support and a propensity towards over supination.

Common Injuries: Excessive supination often leads to lateral ankle instability and sprains, Jone’s fractures, sesamoiditis, and peroneal longus tendinitis.

Sport Risk Concerns: Risk factors are those activities, such as basketball and jumping sports, in which an athlete can come down on and turn the ankle or step on an opponent’s foot.

Management of the A Quad: Ankle strapping or bracing, and orthotic intervention are warranted for “A-Quad” Athletes, especially those with prior injury. Orthotic recommendations include a deep heel cup with lateral heel clip, a lateral flare at the base of the 5th metatarsal, lateral forefoot posting with a 1st met cutout, and heel elevation for associated forefoot equinus, which is commonly associated with this foot type.

B QUAD:

Foot Morphology: The “B-Quad” is a mildly pronated rearfoot combined with a flexible forefoot valgus. It has a lower arch, and vertical or slightly inverted heel and adducted forefoot.

Gait: This foot pronates during contact phase but can resupinate during midstance due to the presence of a flexible forefoot valgus (or plantarflexed 1st ray), which decelerates rearfoot pronation. In propulsion, the hypermobile 1st ray dorsiflexes, transferring weight to the 2nd met. The gait is “in-toed” or “pigeon-toed”.

Common Injuries: The in-toed gait draws the lower limb into internal rotation at the hips leading to muscle imbalances and weakness at the pelvis, hips and core. Common injuries include sacroiliac pain and 1st ray hypermobility and pathology.

Torsional deformities of the limbs, such as femoral anteversion, internal tibial torsion, or metatarsal adductus may cause or exaggerate the in-toeing.

Sport Risk Concerns: “B-Quad” Athletes involved in ballistic sports requiring jumping, cutting and pivoting are at increased risk of injury. Low back pain should be examined carefully to rule out sacral stress fractures (more common in young female adolescents) caused by repetitive stress from sports such as gymnastics, football or other impact sports, or long distance running.

Management of the B Quad: Core and hip strengthening are essential for this foot type to restore proximal stability. Orthotic recommendations include mild medial rearfoot posting and a mild medial skive, and a reverse Morton’s extension. Do not to “over-post” the rearfoot if internal tibial torsion or femoral anteversion are present, since these conditions may necessitate some degree of pronation for compensation.

C QUAD:

Foot Morphology: This foot is an underpronator. At times it may appear “Normal”, and at times “Subtle Pes Cavus”. This foot-type exists when an uncompensated rearfoot varus is coupled with a relatively neutral forefoot. A key distinguishing feature of this foot-type is an obvious toe-out gait pattern with a “normal” or slightly cavus arch height, and a “false” toe sign.

Gait: This gait is “toe-out” (like a duck) because the subtalar joint lacks pronation, making loading the inner aspect of the feet extremely difficult. As a result the body must acquire the necessary motion to load the medial foot by externally rotating the hips, causing tightness of the lateral hip rotators and ITB.

Common Injuries: Hip and ITB tightness often leads to hip bursitis, ITB Syndrome, low back pain, and frequent muscle strains (hamstring, TFL, Sartorius, and rectus femoris), and occasionally femoral stress fractures (more common in females). The inverted heel alters vector forces on the Achilles leading to lateral insertional tendinitis, or cancaneal apophysitis.

Sport Risk Concerns: Ten percent to 24% of athletic injuries in children are hip related. Ballet dancers are most likely to have a hip-related injury, and runners, hockey players, and soccer players are also prone to hip injuries.

Management of the C Quad: C-Quads tend to be very tight, particularly at the hips and back, so stretching is essential. Orthotic recommendations include a moderate heel cup depth with a heel balancing post to “bring the ground up to the rearfoot”. DO NOT add a medial skive to this orthosis as it will not be tolerated well.

D QUAD:

Foot Morphology: This is a congenitally splayed flat foot. A child demonstrating excessive pronation beyond the age of 6yo has “Developmental Flat Foot”. Although early intervention is warranted, treatment is often neglected in the belief that the child will “outgrow it”. Left untreated DFF matures into the adult D-Quad, a moderately over-pronated foot-type. This foot-type occurs when a compensated rearfoot varus couples with a neutral forefoot alignment. The foot looks like a “Fred-Flintstone” foot with a vertical heel and a neutral toe sign.

Gait: This foot immediately pronates at the subtalar joint at heel strike, and continues to pronate throughout midstance. The midtarsal joint unlocks and the midfoot collapses, causing lateral column instability and subluxation of the calcaneal cuboid. This disrupts the peroneal (longus) pulley system and the 1st ray becomes unstable. During propulsion, the 1st and 5th rays dorsiflex causing reversal of the transverse metatarsal arch.

Common Injuries: The planus foot of the adolescent athlete presents with symptoms commonly associated with flat feet, such as: plantar fasciitis, metatarsalgia and neuroma due to reversal of the transverse metatarsal arch, and functional hallux limitus. Freiberg’s Infarction is avascular necrosis of the 2nd metatarsal epiphysis, most common in girls around 13yo. Patellofemoral pain syndrome is another common condition associated with flat feet that involves drifting of the patella out of the trochlear groove.

Sport Risk Concerns: “D-Quad” athletes notoriously have tight heel cords. Adolescent athletes with this foot type could potentially have more muscle cramping and endurance related issues due the inefficiency of gait. This athlete is at risk of a multitude of injuries due to associated muscle weakness of the lower extremities and core, particularly in endurance sports such as running.

Management of the D Quad: Educate the athlete in gastrocsoleus stretching to assure proper performance and results. Avoid stretches where the heel drops off the edge of a step due to midfoot instability. Use night splints in severe cases. Core and hip strengthening are essential for this foot type to restore proximal stability. Orthotic recommendations include a deep heel cup, medial rearfoot posting and medial skive, and in some cases a metatarsal pad with soft topcovers to offload the 2nd met.

E QUAD:

Foot Morphology: The E-Quad Foot is one of the most unique looking feet, with a reverse-lasted foot shape created by an uncompensated rearfoot varus, combined with a structural forefoot varus. The arch is moderately pronated and there is a positive “creasing” toe-sign characterized by a sharp lateral foot angulation at the 5th metabase.

Gait: This foot-type is a rigid foot that is unable to provide the pronatory motion necessary to load the medial aspect of the foot during stance phase of gait. It is for this reason that, when an individual with this foot-type is standing still, they will tend to stand on the outer borders of their feet with the inner side of the foot elevated from the ground. Compensation occurs in propulsion with a rapid abductory twist (medial heel whip) that allows the medial forefoot to eventually load. At times this causes the person to kick themselves!

Common Injuries: Recurrent torque and strain on the foot and the muscles of the lower leg causes maladies like periostitis (shin splints), plantar fasciitis, tailor’s bunionettes, and knee pain. The adolescent athlete may be at risk of Sever’s Disease, Osgood Schlatter’s disease, Jumper’s Knee, and calcaneal apophysitis.

Sport Risk Concerns: Risk of injury to the E-Quad athlete can occur in all sports but especially those that involve distance running, or rapid directional changes such as soccer.

Management of the E Quad: These athletes have imbalances between agonist and antagonist muscle groups and should be screened for flexibility and strength. Orthotic recommendations include a moderate heel cup depth with medial rearfoot posting, and extrinsic medial forefoot posting with a 5th MTH cutout.

F QUAD:

Foot Morphology: The “F-Quad” is commonly referred to a Pes Planovalgus foot. The condition occurs when a severely compensated (pronated) rearfoot couples with an acquired forefoot supinatus, resulting in an extreme flat foot with a valgus heel and an abducted forefoot. This is an acquired foot type usually caused by a D-Quad foot that was not managed properly at a young age. This foot is typically called “Adult Acquired Flat Foot”, although it often occurs as early as 12-13yo.

Gait: All the gait characteristics of the D-Quad are exaggerated in the F-Quad foot and pronation continues throughout propulsion, with excessive abduction of the forefoot (positive splaying toe sign).

Common Injuries: The F-Quad is subject to all the same symptoms as the D-quad but to even a greater degree of pathology. Posterior tibial tendinitis can lead progress to dysfunction and potential rupture or tarsal tunnel syndrome. The abducted forefoot coupled with 1st ray insufficiency leads to HAV deformity with bunions.

Sport Risk Concerns: “F-Quad” athletes will often be plagued by repetitive overuse injuries not limited to the foot and ankle. Shin pain, hip and knee pain, and low back pain are all common. Adolescent bunions occur most commonly in girls between the ages of 10-15. Hallux Valgus affects 22-36% adolescents and is very common in young dancers.

Management of the F Quad: Core and hip strengthening are also essential for this foot type to restore proximal stability. Orthotic recommendations include aggressive medial rearfoot posting and medial skive. Medial forefoot posting may be useful depending on the severity and acquired stiffness of the supinatus; if used, a 1st ray cutout is recommended and on occasion a Cluffy Wedge.

Conclusion: The best way to treat sports injuries in the adolescent athletic is through prevention. Understanding foot types and their propensity for injury allows the pedorthist the opportunity to treat the athlete before the injury happens, while eliminating the chance for repetitive, chronic injuries that could potentially have long term implications into adulthood. In a subsequent article I will discuss how to conduct foot screenings as an effective way to educate your community about pedorthics and help market your practice.

For more information on ABC approved webinars and classes on functional foot typing and pediatrics, email: RobertaN@thequadrastepsystem.com

References:

  1. AOFAS. (2014, July 8). Rising trend in youth sports related injuries. American Orthopaedic Foot & Ankle Society. Retrieved from http://www.news-medical.net/news/20090918/Rising-trend-in-youth-sports-relatedinjuries.aspx
  1. Basra, S. Practical pointers on treating Sever’s Disease in young athletes. Podiatry Today. Oct 2011; 24(10):72-73.
  2. Kelley B and Carchia C. (2013, July 11). “Hey, data data – swing!” The hidden demographics of youth sports. Retrieved from  http://espn.go.com/espn/story/_/id/9469252/hidden-demographics-youth-sports-espn-magazine.
  1. Leonard ZC, Fortin PT. Adolescent accessory navicular. Foot Ankle Clin. June 2010; 15(2):337-47.
  2. Longhino V, et al. The management of sacral stress fractures: current concepts. Clin Cases Miner Bone Metab. Sep-Dec2011; 8(3):19-23.
  1. Lord J and Winell J. Overuse injuries in pediatric athletes. Current Opinion in Pediatrics. Feb 2004; 16(1):47-50.
  2. Micheli LJ, Curtis C. Stress Fractures in the Spine and Sacrum. Clinics in Sports Medicine. Jan 2006; 25(1).
  3. Priscilla TU and Bytomski JR. Diagnosis of Heel Pain. Am Fam Physician. Oct 2011; 84(8):909-916.
  4. Williams BS, Cohen SP. Greater trochanteric pain syndrome: a review of anatomy, diagnosis and treatment. Anesth Analg. May 2009;108(5):1662-70

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World Down Syndrome Day!

March 21 was World Down Syndrome day, and our own Dr. Louis DeCaro, DPM participated in an interview on Mass Appeal, along with cardiologist Meaghan Doherty, MD, on some of the advances made in the treatment of people (particularly children) with Down Syndrome. They brought along superstar Ella, who definitely upped the cuteness factor! Ella has been wearing our littleSTEPS foot orthotics since she was about 2. Check out the interview HERE

The Importance of Treating Feet in Children with Down Syndrome – Part 1

Children with Down SyndromeBy Dr. Louis J. DeCaro with permission from ACFAP QUARTERLY

The Responsibility of the Pediatric Podiatrist

The goal of any practitioner, no matter what their specialty, should be to better the lives of their patients using every tool available to them without bias. As podiatric physicians we have the unique ability to use all forms of medicine, including surgery, on our patients. It is my belief that a well-rounded podiatrist should be someone who recognizes the implications of foot ailments at the earliest of ages in order to prevent adult problems. That is why I have chosen to specialize in podopediatrics.

The feet are the foundation of the body, and from the first step a child takes, deficiencies in the lower extremity begin to create a destructive domino effect on the rest of the human body. It is our job as podiatrists to make sure the feet are taken care of. Whether a child has a simple or complicated medical history, their feet should be screened and treated like those of anyone else. Children with the diagnosis of Down syndrome are no exception.

“Normal” Development of the Pediatric Foot

Let’s talk about what should occur with foot maturation of any child regardless of other medical diagnoses. At the age of 2 years old, the heel bone should sit at about 4 degrees or so everted (means that when you look from the back of someone the heel bone looks like its collapsing down and in.) From 2 years old until 6 years old the “normal foot” should lose about 1 degree of the “eversion” per year and at the age of 6 the heel should stand somewhat “straight up.” This allows an arch to be present. The foot support is on the outside, bringing the center of gravity to a more neutral  stance. Another phenomenon that is “supposed to happen” as we grow older from the age of 0-6/7 is that our lower leg bones start to turn out, and we get a more erect stance. For a majority of those with Down syndrome these two “normal” processes do not occur adequately.

The Down Syndrome Patient

In a patient diagnosed with Down syndrome, there are a multitude of concerns which may be present involving the heart, digestive system, spine, eyes, intellect, joints and mobility. Individuals with Down syndrome typically have problems with collagen, which is the major protein that makes up ligaments, tendons, cartilage, bone and the support structure of the skin. This creates significant laxity from the feet up, thus beginning at a young age the life long destruction of the kinetic chain. “Almost all of the conditions that affect the bones and joints of people with Down syndrome arise from the abnormal collagen found in Down syndrome.”1 The resulting effect in 88% of the Down syndrome population is hypotonia, ligamentous laxity and/ or hyper-mobility of the joints.2 The combination of this ligamentous laxity and low muscle tone contribute to orthopedic problems in people with Down syndrome.

Within the feet, the most common foot problems which can be found in the Down Syndrome patient are “digital deformities, hallux abducto valgus, pes plano valgus, metatarsus primus adductus, hyper mobile 1st ray, brachymetatarsia, haglunds’ deformity, syndactaly and Tailors bunion.”2 Genu valgus and subluxation and/or dislocation of the patella are another concern due to this condition. Hip and spinal issues are often seen as well.1 Overall laxity of the feet has been reported in 88% of children with Down syndrome.3 This percentage is far higher than those without, yet what I see is that often their feet are ignored. The primary medical diagnosis seems to trump the importance of good foot health. I’m here to say it should not. All medical issues should be addressed.

Specifically the Feet

Many patients with Down syndrome have flat feet due to laxity, which we know will not cure itself. We need to screen for this early. This troubling flexible flat foot can be spotted at  a very young age. Unlike many children though, this flat presentation does not go away by the age of 3 but continues causing foundational destruction to the rest of the body as the years go on.

What I have seen with my young Down syndrome patients is an inability of the heel bone to come out of eversion. When that happens the arch, the ankle, and inevitably the rest of the body stay flat and become “dragged down” toward the midline. This causes many kids with DS to have trouble sustaining good strength when they stand and building good core musculature. This “collapse” will impair normal external rotation of some long bones of the body, which leads to multiple postural changes. As well, when physical therapy is called upon to strengthen the child, failure or delay of achieving a strong kinetic chain is inevitable. You can’t build on a poor foundation! Not only will the structure not support it, but due to poor foot alignment the muscles during the exercises may not even fire.

Quality of Life Factors for Down Syndrome Patients

According to Benoit, “when a person has limited ability for movement, there is bound to be some restriction in exposure to learning opportunities and social stimulation, and this privation tends to be reflected in depressed intellectual ability.”4 In other words, by allowing the patient to be more mobile, the patient’s overall well being will be increased. This is critical since those with Down syndrome are living twice as long as they were 25 years ago.5 In fact, studies have shown that those with Down syndrome live longer when they have developed good self-help skills.6 What better way to encourage self-help than to enable a patient to walk, run and be physically active over the course of a lifetime? It is a known fact that with Down syndrome comes an increased incidence of Alzheimer’s disease. With that typically comes an increase in proteins called Amyloids. Researchers at Washington University in St. Louis found that there was a correlation between a sedentary lifestyle and a higher level of amyloid deposition.7 Thus, the science is once again telling us that inactivity can lead to an early demise. Obesity is also common in Down syndrome patients, partially due to inactivity. By correcting the biomechanics, inactivity may be lessened and quality of life may be increased.

Treating the Pediatric Foot

As a pediatric specialist, now with 11 years of experience, what I find troubling is that identifying problem feet at an early age is non-existent in the medical community. This is especially true in those with Down syndrome. Not only are the feet typically last to be looked at but also being that there can be a plethora of other ailments, the feet get little notice. I try to base my practice on the simple fact that “feet are feet!” A person’s foot type is their foot type no matter what medical condition they may or may not have. Unbeknownst to them, many practitioners fall guilty of not recognizing and treating important issues like flat feet when they become focused on what they deem “larger problems.” I have made it a personal mission of mine to get out to groups across the country, such as parental Down syndrome support groups, pediatricians, fellow podiatrists, Early Intervention specialists, PT’s and OT’s and various other specialists, and lecture on the importance of recognizing the feet and its association of their improvement with improved quality of life.

The Overall Plan

Figure 1: A functional UCB type orthotic, with a high medial and lateral sidewall flanges, such as littleSTEPS, combined with supportive footwear, can be highly effective for the typically flexible foot of a young child with Down Syndrome.

Orthoses need to be specifically designed to improve coordination, balance, pain, posture, and strength, and to aid in the development of a more stable and functional gait. These orthoses should be comprised of a deep heel cup, a medial heel skive, and high medial and lateral sidewall flanges. (FIGURE 1) Control of the subtalar joint is paramount. Often kids are over-braced with AFO’s due to lack of foot control. By providing adequate foot control, SMO’s and AFO’s are often times not necessary. I find many children who are “over-braced” lack necessary joint movements and muscle development vital for normal growth and maturity.

Complementary solutions to Early Biomechanical Support

Physical Therapy progress typically associated with Down syndrome motor development is slow; and instead of walking by 12 to 14 months as other children do, children with Down syndrome usually learn to walk between 15 to 36 months. Specific physical therapy recommendations to consider, along with inserts/ orthotics/SMO’s, include: “Strengthening of lower extremity musculature (hips, knees, ankles, and feet) aimed at improving push off
and augmenting support of the knee joint. Heel cord stretching with the heel in neutral alignment when limited passive range of motion exists. Lastly, Dynamic balance activities, such as running or descending stairs, which encourage the child to shift their weight during late swing phase rather than waiting until heel contact.” 8 These are very good  recommendations. I, along with many therapists in my area of practice, am seeing that when orthotic inserts are prescribed along with physical therapy, the improvement really sticks and builds. I see children in therapy all the time that have these everted/flat feet who just either never or too slowly build on strength absent there orthotics. Building better foundation helps those muscles move along faster.

Getting the Down Syndrome Patient to Make an Appointment

But to treat a Down syndrome patient, you have to see them. That is where the education piece is so critical. In many of our communities, we have Early Intervention services for babies born prematurely or with medical concerns. This can be the place where an initial referral can originate. When an EI therapist understands the importance of the feet and biomechanics in the development of any child, she/he can screen for this. With early intervention, Down syndrome patients can have a better outcome in meeting their developmental milestones and lessening their risks of Alzheimer’s and obesity.

In Summary

So what can you do to help? As podiatrists, we are in the unique position of being trusted medical professionals of the lower extremity and its effects on the kinetic chain. This gives us the ability to get out and educate, educate, educate. Preparing the community of people who work with the Down syndrome patients is the key to getting these clients proper foot care early in life in order to allow them a better chance at a long, healthy, active existence. “Treatment of painful feet in patients with Down syndrome is imperative because foot pain leads to relative immobilization and immobile retarded adults do not remain long in the community.”9 My goal as a practitioner and someone who recognizes the progression of foot types is preventing pain by knowing how to deal with it before it happens, coupled with improving overall biomechanical strength and structure. No matter a child’s medical diagnosis, it is important to educate parents and their children what their “foot type” is, and what that may bring them during their adult years. Please feel free to reference my websites www.nolaro24.com and http://www.decaropodiatry.com for additional information regarding my practice and its methodologies.

References
1. Leshin, L. (2003). DS Musculoskeletal Conditions in Down Syndrome.
In Musculoskeletal Disorders in Down Syndrome. Retrieved
May 25, 2012, from www.ds-health.com/ortho.htm.
2 Rogers, C.: Carers Knowledge of common foot problems associated
with people with Down’s Syndrome. University College
Northampton, 2002.
3 Aprin H, Zink WP, Hall JE: Management of dislocation of the hip
in Down syndrome. J Pediatr Orthop 5: 428, 1985.
4 Benoit, E.: Podiatry and mental retardation: The podiatrist’s
role. J.A.P.A., 55: 434, 1965.
5 Young, E. (March 22, 2002). New Scientist. Down’s syndrome
lifespan doubles. Retrieved June 5, 2012, from www.newscientist.
com/article/dn2073-downs -syndrome-lifespan-doubles.html.
6 Eyman RK, Amer J Mental Retard, 95(6): 603-612, 1991.
7 Head, D., Exercise Engagement as a Moderator of the Effects of
APOE Genotype on Amyloid Deposition, January 9, 2012.
8 Selby-Silverstein, L.: The effect of foot orthoses on standing foot
posture and gait of young children with Down Syndrome. NeuroRehabilitation
16 (2001) 183-193.
9 Diamond, L.S. and Lynne, D. et al., Orthopedic disorders in
patients with Down’s syndrome, The Orthopedic Clinics of North
America 12(1) (1981), 57-71.