Growth Arrest and Leg Length Discrepancy

Growth Arrest and Leg
Length Discrepancy
Diego Jaramillo, M.D., M.P.H.
Department of Radiology
Children’s Hospital of Philadelphia
University of Pennsylvania Pearlman School of Medicine
Growth Arrest and
Leg Length Discrepancy
• Normal anatomy
and imaging
characteristics
• Growth arrest
• Leg length
discrepancy
Physeal Anatomy
Physeal Tractography
Vascularity
Physeal – Epiphyseal Differentiation
• Physis remains hyperintense on T2
Fig.14a
Fig.14b
Fig. 146c
Loss of Zone of Provisional Calcification (ZPC) –
Indirect evidence of physeal injury
Growth Arrest and
Leg Length Discrepancy
• Normal anatomy
and imaging
characteristics
• Growth arrest
• Leg length
discrepancy
Legg-Calvé-Perthes Disease:
Predicting abnormal growth
• Metaphysis
–Cysts
• Physis
–Transphyseal
vascularity
Femoral Growth Disturbance
• Short femoral neck
• Relative hypertrophy of greater trochanter
• Physeal scar
Growth Arrest of Proximal Femur
• Physeal scar: “sagging rope sign”
Direct Physeal Injury
• Usually post-traumatic
• Other causes:
–Infection
–Tumor
Osteomyelitis:
Growth Arrest
• 10% of growth arrest
• Two mechanisms:
– direct extension
– ischemia
(meningococcemia)
• Less often with
epiphyseal osteomyelitis
Initial injury October 2003
September 2007
Perichondral Injury
– Physeal injury
– Peripheral
growth arrest
– Osteochondroma
Metaphyseal Ischemia and
Impaired Endochondral Ossification
Chronic stress - physeal damage arrest without bridging
Blount disease
Just like history is written in
geological strata…
and in the rings of trees…
older events are further away from
the physis!
4th dimension:
• Time = Distance from
physis
Growth Recovery Line
• Harris
• Park
• Growth arrest line
Genesis of Growth Recovery Line
7 months
25 months
7 months
25 months
7 months
25 months
Physeal fractures –
Growth Arrest
• 40% of femoral fx. - growth arrest
• Fractures around knee:
–3% of physeal fractures
–57% of cases of growth arrest
• Distal radial fractures:
–60% of physeal fx.; seldom lead to
arrest
MRI of Growth Arrest
•Physeal
interruption
•Growth recovery
line
•Deformity
Growth ArrestClinical Questions
• Bony bridge
–Location
–Size
–% of physis involved
–Deformity
Physeal Fractures –
Prognostic Factors
•
•
•
•
Growth potential: age, maturity
Location
Fracture type
Therapy
Growth Arrest and
Leg Length Discrepancy
• Normal anatomy
and imaging
characteristics
• Growth arrest
• Leg length
discrepancy
Leg Length Discrepancy
Difference > 1cm
• 1-4 cm :
–Resection of bridge
–Stop the growth of the normal side
• Epiphysiodesis:
–Stapling
–Drilling
Epiphysiodesis:
Physeal Closure
Growth Arrest - Therapy
Leg Lengthening
• Differences > 4 cm
• Osteotomy with sparing of
periosteum
• Lengthening with angle correction
Gavriil Ilizarov
Slot Scanning
Technology
• High sensitivity
detector
• 1/8 of dose
Growth Arrest and
Leg Length Discrepancy
• Normal anatomy
and imaging
characteristics
• Growth arrest
• Leg length
discrepancy