legg calve perthes disease donnely 2001 5afad2fc5e0b007027c03a29b821eb3c

Legg Calve Perthes DiseaseJoseph Donnelly, M.D.December 10, 2001

Overview

History Epidemiology/ Etiology Pathogenesis

– Radiographic stages

Presentation/ Exam Imaging Treatment

History

Late 19th century: “hip infections” that resolved without surgery

First described in 1910 Early path studies: cartilaginous islands in

the epiphysis

Epidemiology

Disorder of the hip in young children Usually ages 4-8yo As early as 2yo, as late as teens Boys:Girls= 4-5:1 Bilateral 10-12% No evidence of inheritance

Etiology

Unknown Past theories: infection, inflammation,

trauma, congenital Most current theories involve vascular

compromise– Sanches 1973: “second infarction theory”

Etiology: blood supply

Pathogenesis

Histologic changes described by 1913 Secondary ossification center= covered by

cartilage of 3 zones:– Superficial– Epiphyseal– Thin cartilage zone

Capillaries penetrate thin zone from below

Pathogenesis: cartilage zones

Pathogenesis

Epiphyseal cartilage in LCP disease:– Superficial zone is normal but thickened– Middle zone has 1)areas of extreme

hypercellularity in clusters and 2)areas of loose fibrocartilaginous matrix

Superficial and middle layers nourished by synovial fluid

Deep layer relies on blood supply

Pathogenesis

Physeal plate: cleft formation, amorphis debris, blood extravasation

Metaphyseal region: normal bone separated by cartilaginous matrix

Epiphyseal changes can be seen also in greater trochanter, acetabulum

Radiographic Stages

Four Waldenstrom stages:– 1) Initial stage– 2) Fragmentation stage– 3) Reossification stage– 4) Healed stage

Initial Stage

Early radiographic signs:– Failure of femoral ossific nucleus to grow– Widening of medial joint space– “Crescent sign”– Irregular physeal plate– Blurry/ radiolucent metaphysis

Initial Stage

Initial Stage

Fragmentation Stage

Bony epiphysis begins to fragment Areas of increased lucency and density Evidence of repair aspects of disease

Fragmentation Stage

Fragmentation Stage

Reossification Stage

Normal bone density returns Alterations in shape of femoral head and

neck evident

Reossification Stage

Reossification Stage

Healed Stage

Left with residual deformity from disease and repair process

Differs from AVN following Fx or dislocation

Presentation

Often insidious onset of a limp C/O pain in groin, thigh, knee 17% relate trauma hx Can have an acute onset

Physical Exam

Decreased ROM, especially abduction and internal rotation

Trendelenburg test often positive Adductor contracture Muscular atrophy of thigh/buttock/calf Limb length discrepency

Imaging

AP pelvis Frog leg lateral Key= view films

sequentially over course of dz

Arthrography MRI role undefined

Differential Diagnosis

Important to rule out infectious etiology (septic arthritis, toxic synovitis)

Others:– Chondrolysis -Neoplasm– JRA -Sickle Cell– Osteomyelitis -Traumatic AVN– Lymphoma -Medication

Radiographic Classifications

Describe extent of epiphyseal disease Catterall classification= most commonly

used– 4 groups based on amount of femoral head

involvement– Also presence of sequestrum, metaphyseal rxn,

subchondral fx

Group I

Group II

Group III

Group IV

Lateral Pillar Classification

3 groups:– A) no lateral pillar

involvment

– B) >50% lat height intact

– C) <50% lat height intact

Salter-Thompson Classification

Simplification of Catterall Based on status of lateral margin of capital

femoral epiphysis Group A (Catterall I & II equivalent) Group B (Catterall III & IV equivalent)

Prognosis

60% of kids do well without tx AGE is key prognostic factor:

– <6yo= good outcome regardless of tx– 6-8yo= not always good results with just

containment– >9yo= containment option is questionable,

poorer prognosis, significant residual defect

Prognosis

Flat femoral head incongruent with acetabulum= worst prognosis

Do not treat in reossification stage (>15mos)

Non-operative Tx

Improve ROM 1st

Bracing:– Removable abduction orthosis– Pietrie casts– Hips abducted and internally rotated

Wean from brace when improved x-ray healing signs

Bracing

Non-operative Tx

Check serial radiographs – Q3-4 mos with ROM testing

Continue bracing until:– Lateral column ossifies– Sclerotic areas in epiphysis gone

Cast/brace uninvolved side

Operative Tx

If non-op tx cannot maintain containment Surgically ideal pt:

– 6-9yo– Catterral II-III– Good ROM– <12mos sx– In collapsing phase

Surgical Tx

Surgical options:– Excise lat extruding head portion to stop

hinging abduction– Acetabular (innominate) osteotomy to cover

head– Varus femoral osteotomy– Arthrodesis

Varus Osteotomy

Late Effects of LCP

Coxa magna Physeal arrest patterns Irregular head formation Osteochondritis dessicans

The End