- Discussion: (see limb development);
- at 4 to 6 gestational weeks, the hip joint develops from the cartilaginous anlage;
- by 7 weeks a cleft develops between precartilagenous cells which are programmed to form the femoral head and acetabulum;
- by 11 weeks, the hip joint formation is largely complete;
- femoral head is completely encircled by the acetabular cartilage;
- at late gestation, femoral head grows more rapidly than the acetabular cartilage,
so that at birth the femoral head is less than 50% covered;
- at birth, acetabulum is at its most shallow and most lax inorder to maximize hip ROM which facilitates the delivery process;
- hip is uncontained in extension and adduction reflecting hip shallowness;
- after several weeks, acetabular cartilage develops faster than the femoral head, which allows progressively more coverage;
- normal occurance of hip shallowness and capsular laxity in the neonatal period are inital factors factors involved in DDH
- at 4 to 6 gestational weeks, the hip joint develops from the cartilaginous anlage;
- by 7 weeks a cleft develops between precartilagenous cells which are programmed to form the femoral head and acetabulum;
- by 11 weeks, the hip joint formation is largely complete;
- femoral head is completely encircled by the acetabular cartilage;
- at late gestation, femoral head grows more rapidly than the acetabular cartilage,
so that at birth the femoral head is less than 50% covered;
- at birth, acetabulum is at its most shallow and most lax inorder to maximize hip ROM which facilitates the delivery process;
- hip is uncontained in extension and adduction reflecting hip shallowness;
- after several weeks, acetabular cartilage develops faster than the femoral head, which allows progressively more coverage;
- normal occurance of hip shallowness and capsular laxity in the neonatal period are inital factors factors involved in DDH