Ortho

6-30-99

Lower Extremity

• Infant to toddler
• Ortonlani's reduction test
• Hip abducted from a flexed position—clip or clunk—head of femur back into the acetabulum

• Barlow's dislocation test
• Flexion and adduction and posterior LOD—push down on the head of femur and dislocation—congenital dislocation—most cases resolve themselves
• First bone children—confined in a small tight uterus—60%
• Breach birth—30-50% have this
• Left side pushed up against the sacrum
• More common in females 6:1—affected by maternal hormones (relaxin) relaxing the ligaments
• Respond very quickly a few wks to months—part of well baby exam

• Trenelenburg's test—gluteus medius weakness on wt bearing side
• Many reasons why it may be weak
• Gait that goes along w/it—contralateral side drops down (none wt bearing)

• Head of the femur and the acetabulum together influence the develop of each in the joint
• Pulvinar—fibro-fatty tissue that fills the acetabulum if the femur head is not there
• Triple diapering—keeping the hip flexed and abducted, maintained for several months
• Need to make sure that the hip still receives good blood supply to avoid necrosis—Safe Zone of Ramsey
• Decreased ROM—decreased safe zone

Legg-Calve-Perthes Disease

• Ischemic necrosis of the femoral head
• Idiopathic
• Age 2-12 (mean is 7)
• More common in boys 4or5:1
• Obesity may contribute
• Important not to miss the Dx
• May come in w/thigh or knee pain
• Interruption of blood supply to the femur head
• Osteoblast and clasts die—dead chunk of bone
• Revascularization—return of blood supply
• Big job for osteoclasts which remove the dead bone
• Osteoblasts have to produce new bone
• Subchondral fracture may occur b/c weak new bone leading to secondary ischemia
• Tx is minimize the deformity and maximize the