Paediatric Limb Alignment
If you are concerned about the shape of your child’s legs or feet then please feel free to contact us for a consult in our Alignment Screening for Kids clinic.
Normal Lower Limb Alignment
Many parents worry about the shape of their childs legs and feet, or the way their child looks when they start walking. This information is to show you that leg alignment in children changes with time and it is not necessary to be concerned in the majority of cases.
When children begin walking, at between 10 and 18 months, they stand and walk with a wide base of support. There is usually some bowing of the legs, which are a little externally rotated for stability. The feet are flat in appearance.
In the two to five year age group, the lower limbs start to show a posture of knock knees.
By four to five years, the majority of children develop an arch in their feet and are no longer flat-footed. About fifteen per cent of Caucasians remain flat-footed, based on familial patterns. African and Aboriginal children often present with flat feet which is culturally and genetically normal.
The knock-kneed posture corrects by the age of seven to eight years (with knees together, ankles should just touch).
If the angulation is extreme or asymmetric (only on one-side), further investigation may be required to work out why this has occurred. Surgical options for correcting the angulation as well as the best timing to perform this will be discussed
Rotational Alignment in the Child
Many parents worry about their child having feet that point inward or having them sit in the “W” position. This information is to reassure you that this condition is due to a child’s bone structure and will usually resolve with time. It is not necessary to be concerned in the majority of cases.
When our feet point in a certain direction, they do so as a result of the position of the entire leg. Rotation in a certain direction can therefore occur in the thigh bone (femur), the shin bone (tibia), or finally in the foot itself.
It is normal for children to be born with femurs that are rotated inward (femoral anteversion). They usually derotate naturally by the age of 6 or 7yo.
This image shows how the leg of a child can be affected by rotation to cause the feet to appear internally rotated.
Even if your child has feet that point inward above the age of 7 (persistent femoral anteversion), it is possible to treat the condition without requiring surgery. A paediatric physio will be able to recommend exercises that strengthen up the muscles around the hip joint (external rotators) to ensure the leg points forward.
In the rare cases where your child is significantly incapacitated with trips falls or pain, then it is possible to operate to fix the rotation of the femur or the tibia depending on where the problem lies. The operation involves cutting the bone and manually rotating the ends relative to each other. A plate and screws are used to hold the new position while the bone heals. This is major surgery and good rehabilitation is required to ensure your child recovers fully.
Paediatric Lower Limb Assessment
Bow Legs and Knock Knees
In an adult, our legs are typically equal in length and look straight so that a line from the centre of the hip to the centre of the ankle should pass through the centre of the knee. Sometimes, congenital abnormalities, infection, trauma, or other developmental problems can cause limbs to grow with bow-legs (genu varum) or knock-knees (genu valgum), and sometimes more complex deformities.
In most cases, bow legs and knock knees will resolve of their own accord by the time a child is 7 or 8 years old. In some cases, if the deformity is severe, does not resolve, or causes other problems such as pain, ligament failure or ankle instability, then there are a number of different ways it can be fixed.
During corrective surgery, the pediatric orthopaedic surgeon will use either traditional osteotomy or hemi-epiphysiodesis (Guided Growth). Traditional osteotomy is a more complex procedure that involves cutting the bone, adding or removing a wedge of bone (depending on the type of deformity), and realigning the bone. The realigned bone is then fixed with pins, a rod, or with a plate and screw combination.
While the traditional osteotomy approach is effective, guided growth is often preferred because it is a much less invasive surgical method for correcting angular deformities and allows the surgeon to address multiple deformities during the same procedure.
It is not uncommon for us to have one leg a bit longer than the other. Most people do not notice any problem if the difference is less than 2cm. It is possible to manage a leg length difference of up to 2cm without surgery however if your difference or discrepancy is greater than this, there is a process of assessment and management that should be undertaken.
Epiphyseodesis (Epi-fisio-dee-sis) is a small procedure that is designed to stop the growth of a growth plate. This may be recommended to treat a Leg Length Discrepancy or to prevent further deformity in a limb.
The operation is performed under a General Anaesthetic with X-Ray guidance. A small 1cm incision is placed over the growth plate. A small drill is then used to damage the growth plate with X-rays used to visualise that all the growth plate is affected. A curette is then used to remove any remaining parts of the growth plate.
Wounds are closed with an absorbable stitch and waterproof dressings cover the incisions. Local anaesthetic is used to minimize the post operative pain.
It is usual to experience some bruising and swelling around the wounds. This should resolve in the first 2 weeks following surgery.
It is acceptable to walk following surgery, however we do recommend not to undertake any high impact activity such as running or jumping for 6 weeks. This is because the bone is weakened following surgery, and you do not want it to break