January 2004

Keep an eye on children's feet

 by Dr. Mark N Charrette

Children between the ages of six and twelve should be screened for pedal imbalance. This condition has been implicated in numerous cases of low back, knee, and hip problems, postural fatigue, scoliotic deviations, and plantar fascitis. [1,2] One of the leading causes of spinal‑pelvic distortions is altered foot biomechanics. By screening for and correcting pedal imbalance with custom‑made, flexible orthotics, a chiropractor encourages healthier structural balance and posture in children.

Childhood foot development

A child just learning to stand totters and sways because the foot's weightbearing abilities are minimal. Measurements of foot loading in young children find relatively high values in the midfoot region with metatarsal loading about equal. As the child grows, midfoot loading decreases and the third and fifth metatarsals begin to bear more weight.

Many parents unknowingly watch this pedal development in four phases. Their six‑month‑old has bowed legs and the feet point inward. By age two, the child is walking and the lower extremities seem to straighten out. In another year or so, when skeletal growth accelerates, knock knees and in‑toeing may appear. When growth rates stabilize, usually at age six or seven, healthy alignment of the feet and legs should be observed.

This is the stage of musculoskeletal development when a child should begin to be examined for pedal stability and integrity. Ossification of bony structures is normally well developed, and a meaningful examination can be conducted.

Identifying pedal imbalance

Even the most conscientious parents may be unaware of their child's pedal imbalance. Nonspecific childhood aches and pains are often dismissed as 'growing pains' and not a reason to seek professional care. Also, foot imbalance is usually not a painful condition. Among a group of children with identified pedal instability, 84% were pain‑free. [3] Even though the feet may feel fine, imbalance may be causing symptoms in the back, knees, or other remote location.

Hyperpronation ("foot flare") is highly prevalent among children in the elementary school years, roughly ages six through twelve. Three separate studies conducted at 20‑year intervals found the condition in 29%, 28%, and 35% of test populations. [3] Hyperpronation causes abnormal abduction during gait. Body weight shifts over the foot before stance‑phase muscles are ready to give proper support. [4] The action becomes more pronounced in running, which causes a greater medial shifting of body weight. [3]

A simple visual exam will indicate the need for further testing for pedal imbalance in children. Watch the gait for signs of foot flare and toeing out. If the child is wearing everyday shoes, check the heels for signs of excessive lateral wear, another sign of imbalance.

When the patient is standing barefoot, look for three other important clues to pedal instability: low medial arches; Achilles tendon bowing; and patellar displacement.

Orthotic support

Recommending custom orthotics for children requires consideration of factors that may not be apparent to practitioners accustomed to an older patient population. Activities and attitudes among youngsters are a major influence on their ability to comply with orthotic recommendations. These guidelines can enhance the success of care:

1. Children lead active lives. They put their bodies through maneuvers that adults rarely undertake. Durable orthotics that do not restrict an energetic lifestyle will be appreciated and more easily accepted.

2. Children's bodies are delicate. Bones and tissues are not fully developed before the age of twelve, and some ossification centers are not fully closed until much later. The impact of heel‑strike shock on immature joints can be significant if weakness due to pedal instability exists in the body's natural shock absorbers.

3. Children's feet grow in spurts. Parents should bring the child in for orthotics refitting with every one‑and‑a‑half size change in shoes.

When it has been clinically determined that a young patient can benefit from orthotics, the first step is to determine the most appropriate level of support required. Weightbearing casts, with the foot in the position of function, provide the most accurate documentation of pedal instability and its impact on integrated spinal biomechanics. [5]

Custom‑made, flexible orthotics allow the developing foot to perform controlled movements without disrupting complex structural interrelationships. By limiting pronation through greater arch support, orthotics reduce plastic deformation of pedal tissues. [6] This encourages joint stability which develops optimal support of the lower extremities and, ultimately, greater postural integrity of pelvic and spinal structures.

References

1. Greenawalt MH. "Children and orthotics." Amer Chiro 1989; 4:46.

2. Casselli MA et al. "Biomechanical management of children and adolescents with down syndrome." J Am Pod Med Assoc 1991; 81(3):119‑127.

3. Notari MA, Mittler BE. "Study of the incidence of pedal pathology in children." J Am Pod Med Assoc 1988; 78(10):518‑521.

4. Valmassy R, Stanton B. "Tibial torsion: normal values in children." J Am Pod Med Assoc 1989; 79(9):432‑435.

5. Hyland JK. "Orthotic casting procedures." Chiro Prod 1992; 7(8):40‑41.

6. Christensen KD. "Orthotics: do they really help a chiropractic patient?" ACA J of Chiro 1990; 27(4):63‑71.

(Dr. Mark N. Charrette is a 1980 summa cum laude graduate of Palmer College of Chiropractic. Over the past 17 years he has lectured extensively on spinal and extremity adjusting throughout the U.S., Europe, the Far East, and Australia. In 1976, he received a Bachelor's degree from Illinois State University (summa cum laude) where he was an NCAA All‑American in 1974.)