Significance of Hip Exams in School-Age Children
Hip exams in school-age children are essential for detecting developmental dysplasia of the hip (DDH), Legg-Calvé-Perthes disease, slipped capital femoral epiphysis, and other conditions that can lead to early degenerative joint disease and lifelong disability if not identified and treated promptly. 1, 2
Key Hip Conditions by Age Group
- Infants and young children (0-3 years): Developmental dysplasia of the hip (DDH) is the primary concern, with physical examination recommended at every well-baby visit, as early detection allows for non-invasive and effective therapy 2
- Children 4-10 years: Transient synovitis (most common) and Legg-Calvé-Perthes disease become more prominent, requiring careful clinical evaluation 3
- Adolescents 10-15 years: Slipped capital femoral epiphysis (SCFE) should be the primary consideration, especially in limping obese boys 3
Physical Examination Techniques
- Barlow Test: Essential for infants, involves gently adducting the thigh and applying posterior pressure to identify dislocatable hips 2, 4
- Ortolani Test: Crucial complementary test for infants, involves abducting and lifting the flexed thigh while pushing the greater trochanter anteriorly to detect a "clunk" indicating reduction of a dislocated hip 2, 4
- Limited hip abduction: More useful clinical sign in children older than 3 months, as Barlow and Ortolani tests become less reliable with age 1
- Asymmetric thigh folds: Important sign in older infants and toddlers indicating possible hip pathology 1
- Gait assessment: Critical in school-age children - limping, waddling gait, or toe-walking may indicate hip pathology 1, 3
Imaging Recommendations by Age
- Under 4 months: Ultrasound is the preferred imaging modality for suspected DDH 1, 2
- 4-6 months and older: Radiography becomes more reliable as ossification progresses, with the acetabular index being the most commonly used measurement 2, 4
- School-age children: Radiographs are the initial imaging of choice, with MRI reserved for specific indications 5
Importance of Regular Hip Examinations
- The American Academy of Pediatrics recommends hip examination at every well-baby visit, continuing through childhood 2
- Physical examination remains the most important screening method, with a sensitivity of 85-90% and specificity of 90-95% 2
- Only 25% of children diagnosed with DDH have identifiable risk factors, making regular physical examination crucial for detecting cases without risk factors 6
- Late presentation of hip disorders is a major negative prognostic factor requiring more complex treatment and surgical intervention 2, 7
Common Hip Pathologies in School-Age Children
- Transient synovitis: Most frequent hip disorder in children 4-10 years; self-limiting noninfectious effusion requiring differentiation from septic arthritis 3
- Legg-Calvé-Perthes disease: Idiopathic avascular necrosis causing femoral head deformity, typically occurring between 4-10 years 3, 8
- Slipped capital femoral epiphysis: Inferior and posterior displacement of the proximal femoral epiphysis, most common in adolescents 10-15 years 3
- Labral tears: Increasingly recognized in athletic adolescents presenting with mechanical symptoms after twisting injuries 8, 9
Pitfalls to Avoid
- Delayed diagnosis: Untreated hip conditions can lead to early degenerative joint disease and impaired function 1, 3
- Overreliance on risk factors: Not all children with hip disorders have identifiable risk factors, making physical examination essential 6
- Missing subtle signs: Limited hip abduction and asymmetric thigh folds may be the only signs in children older than 3 months 1
- Inadequate follow-up: Some conditions like DDH may not be present at birth and should be regularly checked for in the first 6 months of life 3
Hip examinations in school-age children remain a critical component of pediatric care, as they allow for early detection and treatment of potentially serious conditions that could otherwise lead to lifelong disability 2, 3.