See how they grow!

William Stripp Memorial Lecture

See how they grow! Maryann Hardy University of Bradford

Indicative Content • Explore the main features of skeletal growth

• Appreciate how variations in skeletal growth and development can result in predictable anatomical (and pathological) appearances • Appreciate how normal growth variations in the juvenile skeleton can mask or mimic common pathologies and influence the acquisition and interpretation of radiographic images • Through use of case examples, examine the appropriateness of diagnostic radiography image acquisition techniques and image quality assessment criteria

What is growth?

Growth, Maturity and Age

Change in body proportions

Bone Ossification • Intramembranous ossification • Endochondral ossification

Intramembranous Ossification

Endochondral Ossification

Developmental Dysplasia of the Hip • Risk factors – – – –

Female foetus 1st born Oligohydramnios Breech position (legs extended)

DDH Risk periods • 12th gestational week – foetal lower limb rotates medially

• 18th gestational week – Hip muscle development completes

• 36th gestational week to term – Restricted hip movement, sustained adduction

• Postnatal – Infant swaddling that maintain hip adduction

DDH Variations in severity Ogden JA (1982) Dynamic pathobiology of congenital hip dysplasia. In: Tachdjian MO, editor. Congential dislocation of the hip. New York: Churchill Livingstone; 1982.

Normal Hip Development

Ogden JA (1982) Dynamic pathobiology of congenital hip dysplasia. In: Tachdjian MO, editor. Congential dislocation of the hip. New York: Churchill Livingstone; 1982.

Shefelbine SJ & Carter DR (2004) Mechanobiological predictions of growth front morphology in developmental hip dysplasia. Journal of Orthopaedic Research 346-352

Developmental Dysplasia of the Hip

Developmental Dysplasia of the Hip Hilgenreiner’s Line

Developmental Dysplasia of the Hip Perkins Line

Developmental Dysplasia of the Hip

Developmental Dysplasia of the Hip Acetabular angle

Acetabular Angle & Pelvis Rotations

Tonnis D (1976) Normal values of the hip joint for the evaluation of Xrays in children and adults. Clinical Orthopaedics and related research: vol 119, pp39-48

Acetabular Angle & Centring point

Phantom Test

Phantom Tests

Acetabular Angle Ranged from 35° at level of greater trochanter to 43° at iliac crests 0.5° variation per cm ….but which image is which centring point?

Learning Summary • Changes in biomechanical forces acting on the hip alters growth patterns and radiographic skeletal appearances in predictable ways • A radiograph can only be described as diagnostic if the radiographer appreciates how image appearances will inform decision making

• Inconsistent or poor radiographic technique may mask or emphasise pathology

The Chest

Goodridge (1995) Pediatric Imaging “The chest X-ray is the most frequently requested and most poorly performed examination in children……..centring is often too low because radiographers are more familiar with adult chest radiography and do not take into consideration the shape of the thoracic cavity in infants which is wider than it is long……..resulting in lordotic appearances”

Meerstadt & Gyll(1994) Manual of neonatal emergency X-ray interpretation

“vertical X-ray beam at right angles to newborn infants protuberant abdomen causes a tendancy to a lordotic view”

Neonatal Chest Radiography

Case 1 CP at level of TV 10 (diaphragm) Lordotic image Head turned Collimation insufficient

Case 2 CP at level of TV 5 (diaphragm) Head Rotated


Case 3 CP at level of TV 8 (just above diaphragm) Collimation insufficient

Case 4 CP at level of TV 7 (just above diaphragm) Head turned Collimation insufficient


Case 5 CP at level of TV 7 (level of diaphragm) Lordotic image Collimation insufficient

Case 6 CP at level of TV 7 (just above diaphragm) Collimation insufficient

Kohn et al (1996) European guidelines on quality criteria for diagnostic radiographic images in paediatrics • “Correct beam limitation requires proper knowledge of the external anatomical landmarks. These differ with the age of the patient according to the varying proportions of the developing body.”

• “The acceptable minimal field size is set by the recognisable anatomical landmarks for specific examinations. Beyond the neonatal period, the tolerance for maximal field size should be less than 2cm greater than this minimal and in neonatal period, less than 1cm at each edge.”





Resize and move the square to centre and collimate for a CXR

Resize and move the square to centre for CXR

Newborn Thoracic Cage

Scheuer L & Black S (2000) Developmental Juvenile Osteology

Rib Orientation

Scapula location

Sprengel’s Shoulder

Neonate

4 year old child

• Carver E & Carver B (2006) Medical Imaging Techniques, Reflection and Evaluation

• Whitley et al (2005) Clark’s Positioning in Radiography (12th ed) • Bontrager KL (2005) Textbook of radiographic positioning and related anatomy (6th ed)

• Ballinger P & Frank E (1999) Merrill’s atlas of radiographic positions and radiologic procedures (9th Edition)

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Centre to over midline of sternal angle. Lower border of collimation should be approximately 2-3cm below the nipples

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No single centring point is advised.

•

Centred to the midsagittal plane at the level of the mammillary (nipple) line

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Centre to T6/7 but the collimated field should extend from mastoid air cells (to demonstrate upper airway) to iliac crests to include inferior costal margins.

Sternum at Birth





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Centre to over midline of sternal angle. Lower border of collimation should be approximately 2-3cm below the nipples

•

No single centring point is advised.

•

Centred to the midsagittal plane at the level of the mammillary (nipple) line

•

Centre to T6/7 but the collimated field should extend from mastoid air cells (to demonstrate upper airway) to iliac crests to include inferior costal margins.

•

Rotation – check symmetry of ribs Lordosis - the ribs must take on a normal anatomical appearance – in other words they should travel obliquely down in a lateral direction from the spine.

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Rotation – Check symmetry of medial clavicles and anterior ribs to spine. Lordosis - medial ends of clavicles should overly lung apices.

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Rotation - Check symmetry of sternoclavicular joints and anterior ribs to spine.

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Rotation – evaluate position of midline structures (e.g. sternum, airways and vertebral bodies) –these should be superimposed Inspiration - 9-10 posterior ribs




•

Very Little! • Carty et al (1994) Imaging children

• Erect is preferable except In neonates

• Slovis et al (2008) Caffey’s pediatric diagnostic imaging (11th ed.)

• Nil

• Hardwick and Gyll (2004) Radiography of Children

• Supine until the child can sit up collimated to within area of landscape 18cm x 24cm cassette

• Hardy & Boynes (2003) Paediatric Radiography

• Centre to area of interest and collimate to the cassette

Learning Summary • Predictable growth of skeletal structures distant to the thorax (e.g. pelvis) result in increased biomechanical forces on thoracic structures (ribs and sternum) alter radiographic skeletal appearances in predicable ways • If radiographers don’t appreciate the variation in location and orientation of skeletal structure during childhood then inappropriate techniques will be used and the quality and diagnostic value of radiographic images will be compromised. • Adult quality assessment criteria can not be applied to neonatal or infant chest radiographs • The published evidence base around paediatric growth and appropriateness of commonly cited radiographic techniques needs to be reviewed.

Pseudoepiphysis

Society of Radiographers (2013) Preliminary Clinical Evaluation and Clinical Reporting by Radiographers: Policy and Practice Guidance • The College’s requirement that ‘red dot’ signalling systems be replaced by written preliminary clinical evaluation systems is therefore appropriate, and will improve yet further radiographers’ contributions to the effective management of patients following imaging.

Society of Radiographers (2013) Preliminary Clinical Evaluation and Clinical Reporting by Radiographers: Policy and Practice Guidance • The College’s requirement that ‘red dot’ signalling systems be replaced by written preliminary clinical evaluation systems is therefore appropriate, and will improve yet further radiographers’ contributions to the effective management of patients following imaging.

• It is expected that locally developed proformas should facilitate communication of one of the following: the imaging appearances are normal / normal for age or known condition/ normal with an anatomical variant at ....; an abnormality is evident at ....

Normal Epiphyseal Growth

Pseudoepiphysis


Pseudoepiphysis Base Index Metacarpal

Pseudoepiphysis


Pseudoepiphysis Base Index Metacarpal

Pseudoepiphysis Causal Stimuli?

Learning Summary • Pseudoepiphyses are normal variations in growth that occur at predictable stages and locations in the long bones of the hand and foot

• If radiographers don’t appreciate natural variations in growth patterns then errors in initial image evaluation will result and as yet, we do not know how incorrect written comments will influence clinical decisions making and treatment.

Indicative Content • Explore the main features of skeletal growth

• Appreciate how variations in skeletal growth and development can result in predictable anatomical (and pathological) appearances • Appreciate how normal growth variations in the juvenile skeleton can mask or mimic common pathologies and influence the acquisition and interpretation of radiographic images • Through use of case examples, examine the appropriateness of diagnostic radiography image acquisition techniques and image quality assessment criteria

William Stripp Memorial Lecture

Thank You See how they grow! Maryann Hardy University of Bradford [email protected]