GP Assessment of Lower Limb Alignment in Children

Orthopaedics

"Orthos" "Paeideia" "Straight" "Children"

Do all children need to have straight legs?

A GP guide to assessing lower limb alignment in children

Introduction

• Parents with young children often present to primary care with an array of concerns about their children's legs

• Many presentations are considered a "Normal Variant" and require simple reassurance, without onward referral to secondary or tertiary care

• This learning module is intended to support you in your clinical assessment of lower limb alignment in children, and guide your management plans.

Index

Nomenclature

Leaning Outcomes

Clinical Assessment

What is Normal?

When to refer?

Quick Reference Guide

Learning Outcomes

By the end of the module you should be able to :

1. Describe the appearance of rotational and coronal plane alignment in a child's lower limbs
2. Describe and carry out a lower limb clinical assessment in a child
3. Recognise where a deformity in a child's lower limbs may be coming from
4. Initiate appropriate management of lower limb alignment problems eg: reassurance/referral to secondary care

Nomenclature

In order to effectively describe what we see in our clinical examination provide accurate information in our referrals, we must use the correct terminology:

Consider using the following terms, in order to decribe your patient:

Nomenclature

Anatomical Planes

Saggittal Plane

Imagine the body has been sliced down the middle, longitudinally, creating a left and right half

Alternatively, imagine a person walks past you and you look at them from the side profile

Deformities such as: excessive lumbar lordosis, thoracic khyphosis and knee hyperextension are saggital plane.deformities

Nomenclature

Anatomical Planes

Coronal Plane

Imagine the body has been sliced down the middle, longitudinally, but perpendiuclar to the saggital plane, creating an anterior and posterior half

Alternatively, imagine a person is walking towards you and you view them head on

Deformities such as: genu varum and genu valgum are coronal plae deformities

Nomenclature

Anatomical Planes

Axial Plane

Imagine the body has been sliced through the middle, creating a superior and inferior half

Alternatively, imagine you are standing on a ladder above a person, looking down,

Deformities such as: intoeing and outtoeing are axial plane deformities

Nomenclature

Coronal Plane Deformity

Typically when we talk about deformity we describe in terms of where the distal segment is in relation to the bone or joint

In children , a common presentation will be in relation to appearances of the legs and we describe how the legs look from the knee distally

Nomenclature

Coronal Plane Deformity

We prefix the description with the word

GENU

Latin for "Knee"

The distal segment of the deformity is described in relation to its direction from the midline

VARUM

- towards the midline

- away from the midline

VALGUM

Nomenclature

Coronal Plane Deformity

Genu Varum - "Bow Legged"

Genu Valgum - "Knock Knees"

Nomenclature

Axial Plane Deformity - Rotational Deformity

Typically, parents will come with concerns regarding where the childs feet are pointing. They often say either one or both feet "turn in" or "turn outwards" We reference the position of the feet with regards to them pointing towards or away from the midline

IN-TOEING - feet pointing towards the midline

OUT-TOEING - feet pointing away from the midline

Nomenclature

Summary

Consider the plane of the deformity you are considering?

• Saggital
• Coronal
• Axial

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When we talk about the deformity - we consider;

• The alignment of the distal segment
• Where this points in relation to the midline: varum/valgum, in-toeing/out-toeing

Question 1/3

A 4 year old girl comes in with both her feet crossing over and "turning in" when she walks.This clinical presentation describes......

Out-toeing

Genu Valgum

In-toeing

Question 2/3

An 11 year old boy presents to clinic with pain on the outside of his knees. When he stands up straight with knees together, you notice his tibias point away from the midline.Which plane is his deformity in?

Right!

Axial Plane

Coronal Plane

Saggital Plane

Question 3/3

Right!

You want to refer a patient to Orthopaedics for management of their genu varum. From which angle should you be assessing this deformity?

Looking from above

Looking from the side

Looking from the front

Nomenclature

Question Review

1. This is a common description of a common presentation. Typically parents describe feet turning in or crossing over - we call this in-toeing

2. When we describe problems with leg alignment we talk about the most distal segment in relation to the midline. In this case the knees are together and the distal segments is the tibia. We are looking at this child from the front, therefore we are assessing deformity in the coronal plane

3. Genu varum is also called "Bow legs" this is a coronal plane deformity. In order to appropriately assess this we look from the front.

Clinical Assessment

This section will offer a simple guide to perfoming a clinical assessment of lower limb alignment in children

The examination techniqes will focus specifically on coronal plane deformities and rotational deformities Other problems can be picked up when performing an overall assessment of a child, but this will not be the focus.

Clinical Assessment

The examination technique will follow the following pattern:

STAND the patient

WALK the patient

ROTATIONAL PROFILE of the patient

Clinical Assessment

STAND the patient

When examining a standing patient, we typically view from the front, back and side

When assessing lower limb alignment we should focus on looking at the patient from the front

What is most important when looking at the patient from the front, is to ensure that the patella are facing forward

When the patellae are not facing forward, it can exacerbate or under represent the appearance of valgus or varus deformity from the knee

Clinical Assessment

STAND the patient

When the child is stood with patellae facing forward, we should next look to the knees and the ankles

If the knees are touching ie: medial femoral condyles are touching, and the ankles are far apart, the alighnment is VALGUS

If the ankles are touching ie: medial malleoli are touching, and the knees are far apart, the alighnment is VARUS

Clinical Assessment

STAND the patient

Varus can be quantified by the Intercondylar distance

Valgus can be quantified by the Intermalleolar distance

Clinical Assessment

WALK the patient

Once an assessment of the child's lower limbs has been made whilst they are standing, we will ask them to walk

Walking is a complex task, and there are many things to observe when examining Gait

When assesing for rotational defomities, we look specifically at 2 things

Patella Progression angle

Foot Progression angle

Clinical Assessment

WALK the patient

Again, as with most descriptions of the limbs, we reference the position of each landmark - patella/foot , in relation to the midline

This can either be internally rotated, neutral, or extenally rotated

FOOT Progression Angle

PATELLA Progression Angle

Internal Neutral External

Internal Neutral External

Clinical Assessment

ROTATIONAL PROFILE of the patient

In-toeing and Out-toeing can originate from the hip/femur, the tibia, or the feet, or from a combination

The elements of a rotational profile assessment are best performed with the patient prone - lying on their front

Clinical Assessment

Clinical Assessment

ROTATIONAL PROFILE of the patient

ROTATIONAL PROFILE of the patient

HIP Rotational Assessment

If in-toeing is coming from the hip/femur, this is usually due to EXCESSIVE FEMORAL ANTEVERSION. This means that femoral neck points forwards, more so than you would expect. In order for the femoral head to sit well within the acetabulum the femur will turn inwards. This will result in the patella rotating inwards, with the foot rotating inwards, giving internally rotated patella and internally rotated foot progression angle

Similarly, if in-toeing is coming from the hip/femur, this is usually due to EXCESSIVE FEMORAL RETROVERSION. This means that femoral neck points backwards, more so than you would expect. In order for the femoral head to sit well within the acetabulum the femur will turn outwards This will result in the patella rotating outwards, with the foot rotating outwards, giving an externally rotated patella and externally rotated foot progression angle

Hip Internal Rotation - 45 degrees

Clinical Assessment

Clinical Assessment

ROTATIONAL PROFILE of the patient

ROTATIONAL PROFILE of the patient

HIP Rotational Assessment

Hip Internal Rotation - 70 degrees

To assess hip rotation, whilst patient lying prone, fllex the knees to 90 degrees

Place one hand on the patients lower back to stabilise the pelvis

Hip External Rotation - 45 degrees

Hold one leg by the ankle, and rotate the leg away from the midline until you feel the pelvis start to tilt under your hand

From the end of the bed, the angle the leg makes perpendicular to the floor is the degrees of internal rotation of the hip

To find the degree of external rotation of the hip, keep you hand on the lower back, and rotate the leg towards the midline

Clinical Assessment

Clinical Assessment

ROTATIONAL PROFILE of the patient

ROTATIONAL PROFILE of the patient

TIBIAL Rotational Assessment

If rotational malalignment is coming from rotation in the tibia, the assessment measure we use is the

THIGH-FOOT ANGLE

Again, the patient is best examined in the prone position, with the knees flexed to 90 degrees

A good tip is to ensure you have corrected the heel into a neutral position , as patiests with a valgus/varus hindfoot that isn't corrected

Neutral Thigh-foot angle

the angle you sare looking to measure is between a line drawn along the length of the thigh, and a line bisecting the length of the foot

Clinical Assessment

Clinical Assessment

ROTATIONAL PROFILE of the patient

ROTATIONAL PROFILE of the patient

THIGH-FOOT ANGLE

If the foot points away from the midlne, then the out-toeing is caused by EXTERNAL TIBIAL TORSION

45 degrees externally rotated thigh-foot angle

If the foot points towards the midlne, then the in-toeing is caused by INTERNAL TIBIAL TORSION

45 degrees internally rotated thigh-foot angle

Clinical Assessment

Clinical Assessment

ROTATIONAL PROFILE of the patient

ROTATIONAL PROFILE of the patient

FOOT Assessment - Heel Bisector

Rotational defomity derived from the feet is most commonly In-toeing due to METATARSUS ADDUCTUS

ADDUCTUS - another description whereby the distal segment of the examined anatomy points towards the midline

To assess whether Metatarsus Adductus is contributing to intoeing:

• With the patient prone, ensure the heel is in a neutral alignment
• Draw a straight line through the middle of the heel along the foot
• It should exit between the 2nd and 3rd toes - if it does, then there is no metatarsus adductus contributing to the in-toeing
• The further it exits laterally on the foot, the more severe the metatarsus adductus

Clinical Assessment

Clinical Assessment

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SUMMARY

• Assess Hip rotation
• Assess Tibial Rotation
• Assess Foot position

• Stand Patient
• Walk Patient
• Rotational Profile of patient

• Too much hip internal rotation?
• femoral anteversion - cause of in-toeing
• Too much hip external rotation?
• femoral retroversion - cause of out-toeing
• Thigh foot angle excessively externally rotated?
• External tibial torsion - cause of out-toeing
• Thigh foot angle excessively internally rotated?
• Internal tibial torsion - cause of in-toeing

• Stand Patient
• Patella pointing forward
• Genu Varum or Valgum?

• Walk Patient
• Where are Patellae pointing?
• Where are feet pointing?

Question 1/3

A 10 year old boy comes to see you with bilateral knee pain. Examination of the knee joints are unremarkable. You stand him straight and ask him to put his knees together. You notice he is struggling to get his ankles close to eachother when he does this.What deformity would you document in the notes?

Femoral Anteversion

Genu Varum

Genu Valgum

Question 2/3

A 6 year old girl presents with constant tripping up and her feet turning inwards when she walks. Which examination technique would be best used to find out if the deformity was coming from femoral anteversion?

Right!

Intercondylar Distance

Hip Rotation

Thigh-Foot Angle

Question 3/3

Right!

With a patient walking towards you, their patella are facing forwards. You notice that the Left foot turns outwards, where do you think the deformity could be coming from?

The Femur

The Foot

The Tibia

Clinical Assessment

Clinical Assessment

Question Review

1. Firstly it is important to consider the patients' presenting complaint. He has knee pain, therefore a knee examination is essential. As part of a knee examination in children, we should always consider alignment. Remember to have the patient stood straight with patella facing forward. With his knees together, we consider the deformity distal to that. His ankles are away from the midline, so this is Genu Valgum

2. Her feet turning inwards suggests in-toeing. We have to consider whether this is coming from the hip, tibia or foot. Femoral anteversion means there is excessive hip rotation. Intercondylar distance is a measure of genu varum, and thigh foot angle is a measure of tibial torsion

13. When we watch a patient walk, we look for te patella progression angle, if the patella is in neutral then the femoral version is usually normal. When we look at the foot progression angle and it is externally rotated in the presence of a normal femur, then we suspect external tibial torsion. Remember, we still have to individually examine each part of the lower limb in isolation to confirm.

What is Normal?

Children don't always have straight legs!

The alignment of children's legs change and devlop as they grow

There can be a wide spectrum of alignment and degree of rotation in childrens legs - this covers +/- 1 standard deviation from the mean We expect them to improve and change with time.

When the perecived deformity is on the outer spectrum of what we consider as normal for age we refer to it as a

NORMAL VARIANT

What is Normal?

Normal Variants - Coronal Plane

When is it ok to have knocked knees or bow legs? Can Genu Varum and Valgum be normal?

Yes! - It can be

We use a graph called the Salenius Curve to determine what the alignment of the legs should be at different ages

What is Normal?

Normal alignment - Coronal Plane

• The area above the age line is varus alignment - bow legs
• the area below the line is valgus alignment - knock knees
• If the alignment is between the top and bottom curved lines - this is a NORMAL VARIANT

Babies and Toddlers are Typically Bow legged with genu varum

Between 18 months - 2 years the leg alignment roughtly straightens to neutral.

From 18 months to 4 years, children become knock knee'd with genu valgum

After the age of 4 years old, the legs start to straighten again - end up with mean valgus of 7 degrees from age 6

Varus - bow legs above midline

What is Normal?

Coronal Plane - what does this mean in practice?

Children often DON"T have straight legs

Neutral - straight legs along line

Bow Legs - acceptable up to the age around 2.5 years

Legs straight - can be from 1 - 2.5 years

Knock Knees - acceptable after the ages of 1 - 7 years

Valgus - knock knees below midline

Normal alignment into adulthood, past the age of 7 has a slight valgus approx 7 degrees - this is difficult to appreciate clinically

What is Normal?

Normal alignment - Rotational Profile - Hip

Range of movement in the hip varies with age

Young children and babies have lots of internal rotation due to increased femoral anteversion Meaning, it is common to present with in-toeing during childhood

Femoral anteversion decreases with age as the "femur untwists"

There is little "untwisting" of the femur after the age of 9 years

Therefore presentation of in-toeing, with a clinical examination of increased hip internal rotation is called - PERSISTENT FEMORAL ANTEVERSION

What is Normal?

Normal alignment - Rotational Profile - Hip

Hip Internal Rotation - 45 degrees

Normal Adult Hip Range of movement:

Internal Rotation - 35-40 degreesExternal Rotation - 40-60 degrees

Most people have up to 90 degree arc of movement Internal + External rotation = 90 degrees

Hip External Rotation - 45 degrees

However: up to 60 degrees internal rotation can be accepted

Hip internal rotation > 70 degrees in a child older than 9 years is no longer considered a Normal Variant

What is Normal?

Normal alignment - Rotational Profile - Tibial Torsion

When considering foot progression angle and tibial torsion:

With patella facing forward, a foot progression angle between 5 degrees of internal rotation and 20 degrees of external rotation can be considered a Normal Variant

This is because, in an adult, the normal Thigh-Foot angle and therefore tibial torsion can be -5 - 30 degrees externally rotated (mean 10 degrees)

In younger children, the normal variant tends to be a much wider range of tibial torsion - from 30 degrees internally rotated (causing in-toeing) to 20 degrees externally rotated

What is Normal?

Normal alignment - Rotational Profile - Tibial Torsion

In young children, there is a significant amount of "untwisting of the tibia"

This can be from significant internal torsion, to reach a more neutral alignment Or this can be from a significant external torsion to a more neutral alignment

There is little "untwisting" of the tibia in either direction after the age of 8 years

45 degrees externally rotated thigh-foot angle

Therefore, after the age of 8 years, internal tibial torsion greater than 5 degrees, and external tibial torsion greater than 30 degrees is no longer considered a Normal Variant

What is Normal?

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SUMMARY

Children Rarely have completely straight legs

• Typically genu varum until 18 months
• Neutral from 18 months to 2 years
• Typically genu valgum 2 years to 7 years

Hip rotation

• All degrees of hip rotation considered normal up to age of 9
• Internal rotation >70 degrees over age of 9 abnormal

Wide range of acceptable variance in alignment NORMAL VARIANT

Thigh-foot angle

Rotational Alignment changes as child grows

• Wider range of accepted tibial torsion up to age of 8
• T-F agle >30 degrees external and >5 degrees internal considered abnormal

• Femur up to 9 years
• Tibia up to 8 years

Question 1/3

A 3 year old comes to see you, his parents are very concerned about his knocked knees. The deformity is bilateral and it is symmetrical. What would your management be?

Refer to metabolic bone team

Refer to Orthopaedics

Reasure Parents

Question 2/3

A 12 year old girl complains of both feet turning in slightly when she walks. When you examine her, you note hip internal rotation of 45 degrees bilaterally and a heel bisector through the 3/4th toes bilaterally. Would your management plan be?

Right!

Refer to Paediatric Orthopaedics

Reassure and discharge

Refer to physio

Question 3/3

A 10 year old boy comes to you with his left foot turning out. You observe a neutral patella progression angle, and a foot progression angle of 40 degrees externally rotated. He has a thigh foot angle of 40 degrees on the left, and 15 on the right. Are you happy to reassure?

Right!

Yes it may get better as he gets older

Yes this is in normal limits

No, he may need an orthopaedic review

What is Normal?

Question Review

1. It is entriely normal for a 3 year old to have knocked knees. The peak genu valgum on the salenius curve is 4 years of age. You can explain to parents it may get worse before it starts to get better. He does not need an orthopaedic referral, nor a metabolic bone team referral.

2. This 12 year old girl has mild intoeing. We don't know her foot progression angle. Her hip internal rotation is 45 degrees, which is on the upper end of the normal range . We can accept up to 60 degrees of internal rotation. Some mild metatarsus adductus may contribute to the intoeing, but this doesn't require orthopedic or physio input.

3 He has unilateral external tibial torsion. He is over the age of 8 years old, it is unlikely to correct. The thigh foot angle being 40 degrees is outside the normal variant acceptance. You may want to discuss whether he would like to be referred for an orthopaedic opinion

When to Refer?

Coronal Alignment Problems

Most children with genu varum or genu valgum will be aysymptomatic

As children get older, they may complain of knee or ankle pain

If they lie within the boundaries of the Salenius Curve for Normal Variants, under the age of 7 - no referral to Secondary Care is required

If there is excessive varum or valgum outside of the curve, they may need to be seen by a Children's Orthopaedic Surgeon. We have a simple operation called "Guided Growth" to correct coronal alignment before the child reaches skeletal maturity, preventing ongoing pain into adulthood

When to Refer?

Coronal Alignment Problems

Children with coronal alignment deformities should be referred to Children's Orthopaedic Services if:

• They have Genu Varum past the age of 3 years
• They have significant Genu Valgum past 7 years
• They have an asymmetical deformity
• They have a unilateral deformity
• They have a history of lower limb trauma, infection or surgery
• They have a suspicion of a metabolic bone condition or a skeletal dysplasia

Otherwise, parents can be safely reassured that their children should improve with age

When to Refer?

Rotational Alignment Problems

A common presentation of rotational alignment problems will be in-toeing and out-toeing causing tripping over or falls Occasionally it will be associated with hip/knee/ankle pain, but this is not common

As the femur and tibia typically "untwist" and correct their own alignment, we DO NOT operate for in-toeing or out-toeing before the ages of 8-9 - depending on femur or tibia

Unfortunately physiotherapy cannot prevent tripping and falls associated with in-toeing and out-toeing, major surgery is the only way to correct

When to Refer?

Rotational Alignment Problems

Surgery to correct in-toeing and out-toeing is a significant undertaking, and should not be done because the child doesn't like how they look when they walk It requires breaking, twisting and re-fixing the long bones, and allowing them to unit

They should only be referred to Children's Orthopaedic Services if:

• Their rotational malalignment comes from the femur - over 9 years
• Their rotational malalignment comes from the tibia - over 8 years

AND

• They have significant hip/knee/ankle pain and or
• Significant gait issues with walking or running, impacting daily life

You have now completed the E-Learning Module for: Assessing Lower Limb Alignment in Children

Please return to the index page to access your quick reference guide to help you in your future practice

Quick Reference Guide