}]]}]}]}] 2c:Tf2c,

### Definition - **Developmental Dysplasia of the Hip (DDH):** A spectrum of conditions ranging from mild acetabular dysplasia to irreducible dislocation of the femoral head from the acetabulum. - Can be unilateral or bilateral. ### Risk Factors (mnemonic: BREECH) - **B**reech presentation (especially frank breech) - **R**ight hip (3x more common than left for unilateral) - **E**lasticity of ligaments (maternal hormones) - **E**xchange of amniotic fluid (oligohydramnios) - **C**ongenital musculoskeletal anomalies (e.g., torticollis, metatarsus adductus) - **H**istory (family history of DDH) - **F**emale sex (4-6x more common) - **F**irstborn child ### Clinical Presentation #### Neonates & Infants (< 3 months) - **Ortolani maneuver:** Reduces a dislocated hip (clunk as femoral head enters acetabulum). - **Barlow maneuver:** Dislocates an unstable hip (clunk as femoral head exits acetabulum). - **Asymmetric gluteal/thigh folds:** Common but non-specific. - **Limited hip abduction:** Most reliable sign after 3 months. #### Older Infants & Children (> 3 months) - **Limited hip abduction:** Key sign. - **Galeazzi sign (Allis sign):** Apparent leg length discrepancy when hips and knees are flexed (dislocated side appears shorter). - **Trendelenburg gait:** Positive sign if unilateral (pelvis drops on unsupported side). - Toe walking, waddling gait (if bilateral). ### Diagnosis #### Imaging - **Ultrasound (US):** Preferred for infants < 4-6 months (cartilaginous femoral head). - **Graf classification:** Assesses acetabular morphology. - Dynamic assessment (stress views). - **X-ray:** Preferred for infants > 4-6 months (ossification of femoral head). - **Key X-ray lines:** - **Hilgenreiner's line:** Horizontal line through triradiate cartilages. - **Perkin's line:** Vertical line perpendicular to Hilgenreiner's, passing through lateral margin of acetabulum. - **Shenton's line:** Smooth curvilinear line from medial aspect of femoral neck to inferior border of superior pubic ramus (disrupted in dislocation). - **Acetabular index:** Angle formed by Hilgenreiner's line and a line connecting the acetabular roof (normal < 30° in newborn, decreases with age). - Femoral head should be in inferomedial quadrant formed by Hilgenreiner's and Perkin's lines. ### Treatment #### < 6 months - **Pavlik Harness:** Most common and effective. - Holds hips in flexion and abduction. - Worn full-time until hip is stable, usually 6-12 weeks. - Regular follow-up with US/X-ray. - Complications: Femoral nerve palsy, avascular necrosis (AVN) of femoral head (if extreme flexion/abduction). #### 6-18 months - **Closed Reduction:** Under general anesthesia, followed by spica cast for 3 months. - **Open Reduction:** If closed reduction fails or is not possible. Followed by spica cast. #### > 18 months - **Open Reduction:** Almost always required. - Often combined with osteotomies (pelvic and/or femoral) to reshape bone and improve hip stability. ### Prognosis - Early diagnosis and treatment lead to excellent outcomes. - Untreated or late-diagnosed DDH can lead to: - Persistent hip instability. - Early onset osteoarthritis. - Pain and functional limitations. - Leg length discrepancy. 26:["$","main",null,{"className":"pt-[57px]","children":["$","div",null,{"className":"max-w-7xl mx-auto px-4 sm:px-6 py-6","children":[["$","nav",null,{"aria-label":"Breadcrumb","className":"mb-

Developmental Dysplasia of Hip

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