Congenital deformities of the hip (synonyms: Congenital acetabular dysplasia; Congenital bilateral subluxation of the hip joint; Congenital coxa valga; Congenital coxa vara; Congenital dislocatable hip; Congenital unilateral subluxation of the hip joint; Congenital flexion deformity of hip joint; congenital hip deformity; congenital hip joint disease; congenital hip dislocation; congenital subluxation of hip joint; Congenital luxatable hip; congenital preluxation of hip; congenital rotational deformity of hip joint; congenital unstable hip joint; congenital increased antetorsion of femoral neck; abnormal hip flexion; abnormal femoral flexion; bilateral congenital hip dislocation; bilateral congenital hip dislocation; bilateral luxatio coxae congenita; coxa valga congenita; Coxa vara congenita; Dysplasia hip; Unilateral congenital hip dislocation; Unilateral congenital hip dislocation; Unilateral luxatio coxae congenita; Hip dysplasia; Hip joint dysplasia; Hip joint instability; Hip joint maturation delay; Congenital hip dislocation; Congenital hip dysplasia; Congenital hip joint contracture; Congenital hip luxation; Congenital hip shortening; Congenital positional anomaly of the hip joint; mild dysplasia hip; mild hip dysplasia; mild hip joint dysplasia; luxatio coxae congenita; luxatable hip; rotational anomaly of the hip; Rotational anomaly of the femur; severe dysplasia hip; severe hip dysplasia; severe hip joint dysplasia; subluxatable hip; increased antetorsion of the femoral neck; ICD-10-GM Q65. -: Congenital deformities of the hip) include primarily:
- Congenital dislocation of the hip joint (hip joint not fully closed and also exhibits dislocation, i.e., dislocation), unilateral/bilateral
- Congenital subluxation (incomplete dislocation) of the hip joint, unilateral/bilateral.
- Congenital unstable hip joint – (sub-)luxatable hip.
- Congenital acetabular dysplasia (malformation of the acetabulum).
- Coxa valga congenita – congenital steepness of the femoral neck with a femoral neck shaft angle of > 140 °.
- Coxa vara congenita – congenital malposition of the femoral neck with a femoral neck shaft angle of < 120°.
- Increased antetorsion of the femoral neck (twisting of the femoral neck forward) – common in congenital hip dislocation.
Sex ratio: newborn girls to newborn boys is 6: 1 (regarding hip dysplasia).
Frequency peak: coxa vara (“outwardly bent” hip) is common in the elderly and increases the risk of femoral neck fracture. Coxa valga is common in newborns and young children.
The prevalence (disease incidence) for congenital hip dysplasia in newborns is 2-5%. The incidence of dislocation is thought to be 0.2%.
Course and prognosis: The majority of hip dislocations develop after birth. In 80 % of the cases, the unstable hip joint, if it can still be assigned to an early stage without hip luxation, regresses by itself and the hip joint continues to develop normally. If the instability persists or worsens, appropriate early therapy is important to prevent secondary damage. The prognosis is best if the instability of the hip joint is recognized and treated immediately after birth. If hip dislocation already exists at birth, the prognosis is worse.
