Before considering abnormal gait in children, it is essential to know the normal milestones. There is some variation, so a child falling just outside these parameters should not immediately be classed as abnormal unless the margins are wide or other factors point towards pathology.
A child normally begins to walk between 12 and 14 months, climb stairs on hands and knees by about 15 months and run awkwardly by 16 months. Climbing downstairs is not usually achieved until 20 to 24 months.
Walking up stairs using alternate feet occurs at about three years, hopping by four and skipping by five, and balancing on one foot for about 20 seconds by six to seven years.
1. Variations of normal gait
Initially children usually have externally rotated legs with some bowing, and use a broad base with their arms out to aid balance.
They usually have flat feet and take high steps. By about 15 to 18 months the heel starts to strike the ground first, and they swing their arms. By the time they are two they can run quite well and change direction easily.
Some variations occur quite commonly, and most resolve spontaneously by the age shown in brackets: genu varus (bow legs - 18 months), habitual toe walking (three years), in-toeing (up to eight years), genu valgus (seven years) and flat feet (six years).
If these variations persist, are progressive, or accompanied by pain or limited function, they should be investigated.
In particular, a child below the 25th percentile in height with genu varus or valgus should be considered for X-ray to exclude skeletal dysplasia or rickets.
2. Descriptions of abnormal walking
With a stepping gait, the whole leg is raised at the hip to ensure adequate ground clearance (a foot drop gait). It can be seen with peripheral neuropathies, spina bifida and polio.
A spastic gait is associated with inversion of the foot and foot dragging. It occurs in diplegic and quadriplegic cerebral palsy and stroke.
Trendelenberg's gait is caused by weakness of the hip abductors. The feet, hips and knees are externally rotated, and when weight is borne on one leg, the opposite side of the pelvis drops, rather than rising as normal.
If both sides are affected, the patient has a rolling gait. A Trendelenberg gait is seen in slipped capital femoral epiphysis, Legg-Calve-Perthes disease (idiopathic osteonecrosis of the femoral head), hip dysplasia and inherited myopathies, as well as spina bifida and cerebral palsy.
Habitual toe-walking is not uncommon, and if asked the child can usually walk normally. Persistence of the symptom with failure of heel contact is seen in diplegic cerebral palsy or more rarely, a lysosomal storage disease.
A 'clumsy gait' is a term used when there are problems with motor co-ordination. Various difficulties may be associated with impairment of fine and coarse motor skills, including frequent falls, difficulty with feeding or getting dressed and poor writing ability. In these apparently clumsy children, exclude underlying pathology such as mild cerebral palsy, cerebellar ataxia, lower motor neuron disorders, inflammatory arthritis or myopathies.
An antalgic gait refers to a child who avoids weight-bearing on the affected side. Typical causes are injury to the foot or juvenile arthritis. It is important to remember when a child is unwilling to weight-bear that unwitnessed trauma is not uncommon.
A 'peg leg' gait is caused by an excess of hip abduction as the leg moves forward. It usually occurs when one leg is longer than the other, if there is an inflammatory arthritis, or in hemiplegic cerebral palsy.
3. Some common problems
Even without a precise identification of the type of gait exhibited, a number of common diagnoses should be borne in mind when a child presents with walking difficulties.
A toddler's fracture is an isolated spiral fracture of the tibia and usually presents as a problem with walking. It is an important diagnosis because there is no external sign of injury, and often the parent cannot recall a specific incident.
Toddlers often fall without apparently hurting themselves, and this fracture has led to accusations of child abuse. However, evidence suggests that nearly all of these fractures have an accidental aetiology.
Legg-Calve-Perthes disease often presents with a limp. This is due to impairment of the blood supply to the capital femoral epiphysis. Early treatment, especially in the younger child, can prevent the development of permanent disability.
Osgood-Schlatter disease is caused by excessive traction on the patellar tendon causing inflammation at its insertion into the immature tibial tubercle. The diagnosis is usually straightforward and most cases resolve with rest.
Child abuse should be considered in any child who presents with walking difficulties where there is no simple pathological explanation. Other relatively common causes of gait abnormalities are cerebral palsy, spina bifida and juvenile arthritis.
Appendicitis can present with difficulty in walking, usually where the abdominal pain component is not prominent.
A slipped femoral epiphysis, septic arthritis, haemophilia, muscular dystrophies and malignant disease of bone or muscle are all rarer causes of an abnormal gait.
It is worth mentioning that with increasing obesity in children, youngsters who are grossly overweight may exhibit difficulty walking. However, it would be unwise to attribute gait problems to obesity without making sure there is no other pathology.
- Dr Barnard is a former GP from Fareham, Hampshire