The aim of this study was to investigate the effects of physical therapy and rehabilitation applications on the hip and defined functional parameters in children with developmental hip dysplasia.

Developmental dysplasia of the hip (DDH) is one of the most important factors causing disability in childhood. DDH is the reason for 29% of all primary hip replacements under 60 years of age. The treatment of DDH, which is applied after an average of 12 months of age in infants, becomes difficult due to shortening of the extra-articular soft tissues, acetabular dysplasia, capsular restriction, and increased femoral anteversion. In the treatment of subluxation, dislocation and residual acetabular dysplasia, many pelvic iliac osteotomies are actively applied to increase joint stability and compatibility of the femur acetabulum. The treatment method and physical therapy to be applied in the treatment of DDH vary depending on the age and type of pathology. Therefore, osteotomies can be performed in isolation or in combination with open reduction of the hip and femoral osteotomies. The general opinion about the minimum patient age for iliac osteotomies (Dega osteotomy, Salter innominate) is that it can be done in children who are at walking age. With Dega osteotomy, anterior, lateral and mainly posterior deficiencies are eliminated by changing the acetabular inclination and structure and increasing the grip between the femoral head and the acetabulum.

In the literature, there are studies on the examination of various angular values of the hip (alpha, beta, coverage angle), various classification methods, and whether the postoperative follow-up of children who underwent open, closed reduction and osteotomy requires a reconstructive surgical procedure. No studies have been found on the strength of the hip muscles due to the application of surgical techniques in children with DDH who have weak hip, chorea and lower extremity muscles due to intrauterine and structural conditions. There are no studies on how the affected muscles affect the hip parameters and functional capacities of children with DDH. We think that hip muscle strength, femoral head and anteversion angle, acetabular index, hip adductor muscle tension are important in terms of hip stability and functionality in children aged 2-5 years. Due to the lack of studies in this field in the literature, this study; The aim of this study was to examine the effects of physical therapy and rehabilitation practices on hip and determined functional parameters in children with developmental dysplasia of the hip.

Inclusion Criteria:

• 2-5 years old,
• Diagnosed with developmental hip dysplasia,
• Have not undergone any foot surgery,
• Not having any neurological or rheumatological disease,
• Having sufficient cooperation to understand and correctly apply the tests,
• Patients with informed consent from their families were included.

Exclusion Criteria:

• Having neurological problems,
• Meningomyelocele (diagnosed with Spina Bifida),
• Mental retardation and uncooperative,
• Children with inflammation, spasticity, spina bifida, arthrocentesis,
• Down syndrome-related dislocation,
• Children who could not obtain informed consent from their families were excluded from the study.

Participants didn't know taking which exercise treatment methods.