Click here to load reader
Post on 12-Apr-2017
Embed Size (px)
Perthes Disease Presented By Siti Nur Rifhan Kamaruddin
OVERVIEWAlthough the incidence is only 1 in 10,000 it should always be considered in differential dx of hip pain in young children.Pts usually 4-10 years old and often show delayed maturityBoys affected 4x than girls
DEFINITION: A disorder of childhood characterized by avascular necrosis of the femoral head
PATHOGENESIS Infants: femoral head is supplied by - Metaphyseal vessels which penetrate the growth disc - Lateral Epiphyseal vessels in retinacula - Scanty vessels in Ligamentum Teres The metaphyseal supply (MS) gradually declines. 4 years old: MS has disappeared
7 years old: The vessels in Ligamentum Teres developed
Between 4-7 years, Femoral Head depends entirely on the lateral epiphyseal vessels
Between 4-7 years old : Femoral head depends almost entirely on lateral epiphyseal vessels whose situation in retinacula makes them susceptible to stretching & pressure from an effusionPrecipitating cause : An effusion into hip joint following - Trauma - Synovitis
PATHOLOGYStage 1: Bone DeathEpisodes of ischemia leads to part of bony femoral head dies. X-ray looks normal but it stops enlarging
Stage 2: Revascularization and RepairNew blood vessels enter the necrotic area and new bone is laid down on dead necrotic area.X-ray - increase In densityIf only part of epiphysis is involved, rapid bony architecture is completely restored.
Stage 3: Distortion and Re-modelling. If large part of bony epiphysis is damaged & the repair process is slow- Epiphysis may collapse and growth of the head and neck will be distorted. Epiphysis ends up as - Flattened (Coxa Plana) - Flat and enlarged ( Coxa Magna) - Femoral head will be incompletely covered by the acetabulum.
CLINICAL FEATURESAge 4-8 years oldComplaint of pain and starts limping Symptoms complaint for weeks or recur intermittentlyHip may looks normal although there is little wasting All Range of Movement are limitedPt may have an antalgic gait with limited hip motionPassive ROM are limited, esp. internal rotation and abduction
INVESTIGATIONPlain RadiographTo establish diagnosis : Do Hip radiographs, anteropoesterior and frog-leg lateral views of the pelvis Initial radiographs can be normal.X-Ray ChangesEarly Changes : Increased density of Body Epiphysis and Widening of joint spaceLate Changes : Flattening , Fragmentation and lateral displacement of the epiphysis with rare fraction at metaphysis.
Herring ClassificationThe Herring Classification addresses theIntegrity of the lateral pillar of the femoral head.
Group A: Normal height of lateral pillarGroup B : There is collapse of lateral pillar (less than 50%)Group C : There is more than 50% loss of the lateral Lateral pillar height. These pt usually end up with significant distortion of the femoral head.
CT Scan Allow early diagnosis of bone collapse Demonstrates subtle changes in the bone trabecular patternUltrasonographyPreliminary diagnosis of transient synovitis of the hip and the onset of CP. Hip effusion with capsular distension is well depicted on sonographic imagesMRIAllows more precise localization of the femoral head
GENERAL MANAGEMENTSkin traction as long as the hip is painful (usually takes 3 weeks)Encourage movement once pain is subsided. Further treatment is taken by assessment of clinical and radiographic features. Choice of further treatment : - Symptomatic treatment - Containment
Onset under Age 6Partial involvement of femoral headAbsence of metaphyseal involvementNormal femoral head shape
No Active treatmentneededPoor Prognosis
Age over 6 years old Involve the whole femoral head Severe metaphyseal rarefraction Lateral displacement of femoral head
Symptomatic Treatment Pain control if necessary Gentle exercise to maintain movementRegular assessment ContainmentContainment means keeping the femoral head well seated as fully as possible within the acetabulumCan be achieved by : - Holding the hips widely abducted in plaster of removable splint ( will take at least a year) - Varus Osteotomy of femur or innominate osteotomy of the pelvis.
TREATMENT GUIDELINEUnder 6 years Symptomatic Treatment - Activity modification
Children Aged 6-8 years# Here the bone age is more important than the chronological age Bone Age at or below 6 years: Lateral pillar Group A, B : Symptomatic Lateral Pillar Group C : Abduction brace Bone Age over 6 years :Lateral Pillar Group A & B : Brace or Varus osteotomyLateral Pillar Group C : Outcome not affected by treatment
REFERENCESApley and Solomons Concise System of Orthopedics and Trauma 4th Edition. CRC Press