兒童常見的步姿問題 Common Walking Problems in Children
Skeletal development of lower limb The maturity of lower limb alignment depends on the proper stimulation during growth. The baby is born in a flexed posture. With normal development and stimulation, our bones, joints and muscles matures with time. This pamphlet introduces four common conditions of skeletal development in children including bow leg, flat feet, in-toeing and tip-toeing walk. O 1
I. Bow leg, O ( 1) - Babies are born with physiologic bow legs. This is normal at birth. The knee becomes straight at around the age of 2, then bends out afterwards. Maximum bending out angle occurs at about age 3. It then gradually reduces and becomes stabilized at age 9. - O Figure 1 2
Knee alignment Valgus varus 3 Age Figure 2 Figure 2 shows a graph of knee angle changes against age. The knee of a new born baby is in slight varus (bend in, figure 3a), with normal development, the knee gradually straightens (figure 3b) and subsequently becomes valgus (bend out, figure 3c). The maximum valgus angle is achieved at around 3 years of age. The knee valgus slowly reduces and remains at mild valgus at skeletally maturity. 2 ( 3a) ( 3b) ( 3c) 3
(a) (b) (c) Figure 3 Bow legs not only cause cosmetic problem, but may also lead to pain. When the knee is in varus, the inner side of knee joint will be over stressed. In such situation, the ankle will then be forced to varus. The weight bearing point of the sole will shift to the outer side causing development of callosity. Shoe wear is therefore easily broken. O 4
As bow legs improve with growth, there is no urgency for treatment. The doctor will observe the change regularly. Strengthening exercise for the knee such as cycling and stepping up and down can improve the stability of knee and thus provides better support. Physiotherapist will measure the knee alignment at regular intervals. Should there be any deterioration of condition, the patient will be advised to seek medical consultation for further investigation. O 5
2. Flat feet Physiological flat feet are present in babies and toddlers. With normal development, foot arch will gradually develop and mature at around age 6. Flat feet may persist after age 6 in children who have familial flat feet, lax joints or pathological flat feet such as congenital bone disease. Flat feet are frequently seen on children with hypotonia. This is because low muscle tone will lead to inefficiency of the muscle pulls that hold the normal foot arch. ( ) Functional problem : medial foot pain inability to hop poor running or jumping easy tiredness Figure 4 Flat foot Normal arch Flat arch 6
The heel cord of flat feet will be shortened as a result of mal-alignment of the foot bones. The shorter the heel cord, the more deformity is resulted. Therefore patient needs to do stretching exercise and massage (figure 5) to stretch out the tight heel cord (figure 6). Moreover, the calf muscles will be weakened as a result of mal-aligned muscle pull. Therefore strengthening these muscles is also important (figure 7 and 8). ( 5) ( 6) ( 7 8) Exercise for flat feet Figure 5 Calf massage 7 Figure 6 Heel cord stretch
Figure 7 Calf strengthening Figure 8 Tibialis posterior strengthening 8
There are many small muscles at the foot and they may also help supporting the foot arch. Therefore strengthening exercise for these small muscles such as walking on the beach (figure 9) or griping towel with toes (figure 10) may be beneficial. ( 9) ( 10) Figure 9 Walking on the beach or uneven surface 9
Figure 10 Toe griping exercise using towel In severe cases, orthotic treatment (figure 11) can restore the mal-alignment and the heel valgus improves. ( 11) 10
Figure 11 Arch support When choosing shoes, parents should select shoes with arch support. The shoe materials should not be too hard or too soft. The size of shoe must be just fit and should not be too large or too small. A pair of oversized shoes will lead to easy tripping and the arch support will not fit the child either. 11
3. In-toeing walk Children below age of 5 may walk with mild in-toeing. Majority of them are usually due to poor sitting posture such as W -sit on the floor (figure 13). ( W 13). Cause of in-toeing walk The followings are the possible causes of in-toeing walk (figure 12) :( 12) B. Internal rotation of tibia A. Deformity at thigh bone (anteversion) C. Forefoot adduction Figure 12 12
A. Deformity at thigh bone (femur) Children below age of 5 may walk with mild in-toeing. Majority of them are usually due to poor sitting posture such as W -sit on the floor (figure 13) and increased femoral anteversion angle (an angle formed between femoral neck and the knee axis, figure 14). With normal skeletal development, this angle will gradually decrease and become normalized. However, this angle will not decrease in case of pathological condition and/or abnormal posture. The larger the anteversion angle, the more the in-toeing. ( W 13) ( 14) Normal Figure 13 Avoid W -sit W Anteversion 13 Figure 14 Increased femoral anteversion
Figure 15 shows a clinical test for femoral anteversion. The tester rotates child's hip in both internal and external rotations and compares the difference. If femoral anteversion is increased, there is excessive internal rotation of hip and reduced external rotation. 15 Hip internal rotation Hip external rotation Figure 15 Clinical test for femur mal-rotation: excessive internal rotation of hip and reduced external rotation. 14
B. Internal rotation of tibia (figure 16) 16 The tibia bone may be deformed and internally rotated as happened in poor sitting posture in situation A. Regular assessment is needed. Stretching out any tight soft tissues may improve the situation and gradual normalize this deformity. ( ) (A ) Figure 16 shows a clinical test of measuring the rotation of tibia by taking the foot-thigh angle. In this test, the child is lying prone, knee flex to 90 degrees and the foot and thigh axes are compared. Normal angle is 10 to 15 degrees outward. 16 90 10-15 15 Figure 16 Internal rotation of tibia
C. Forefoot adduction Forefoot adduction (figure 17) may also contribute to the in-toeing. It may be caused by inheritance or inborn. Figure 17 Forefoot adduction Functional problem : In-toe walking not only cause awkward walking pattern, but also leads to easy falling as feet are easily catching each other. Furthermore, since the muscle pulls are not in the original mechanical advantage positions, these muscles are weakened and children may find difficulty in running and jumping. 16
Exercise for in-toeing gait Figure 18 Stretching for left hip Treatment for in-toeing mainly focuses on stretching out tight hip structures. Figure 18 shows stretching for left hip and figure 19 shows stretching both sides to increase flexibility of external hip rotation. 18 19 17
Figure 19 Stretching for both hips Figure 20 shows stretching exercise for forefoot adduction. The heel is stabilized and the forefoot is stretched towards the little toe. Figure 20 Stretching exercise to improve forefoot adduction 18
4. Tip-toeing Figure 21 Toe walking (figure 21) may occur at the early stage of learning to walk, i.e. at around age 1. It may be transient for months and subside itself if no other pathology behind. Toe walking is usually benign but clinicians need to exclude other possible neuromuscular diseases. ( 21) 19
Management A child walk with tip-toeing requires a lot of muscle work at calf. This may lead to muscle fatigue and pain. Besides, balancing will be difficult as there is only point-contact at toes instead of the whole foot. Prolonged tip-toe walk will lead to shortening of the heel cord. Children will have difficulty in squatting. Shoe wears are easily worn out as the toecap drags on the floor. Treatment for tip-toeing is usually by observation, stretching out the tight heel cord (figure 22 and 23) and orthotic treatment (figure 24) in severe cases. ( 22 23) ( 24) Figure 22 Heel cord stretch Figure 23 20
Functional problem calf muscle fatigue calf pain easy falling on uneven surface inability to squat wearing out of toecap Figure 24 A hinged ankle-foot-orthosis to stop planta-flexion 21
Conclusion Walking problems in children may be multi-factorial and complex. This pamphlet cannot include all problems and treatments. If there is any query, please consult a doctor or physiotherapist. References: Li YH and Leong JCY, Intoeing gait in children, HKMJ 1999;5:360-6 Kamegaya M and Shinohara Y, Gait disorder and leg deformities in children, J Orthop Sci, 2002:7:154-9 Pernet J et al, Titomanlio L, Early onset toe-walking in toddlers: a cause for concern? J Pediatr. 2010 Sep;157(3):496-8 22
ACKNOWLEDGEMENT Supported by Patient Empowerment Programme New Territories West Cluster