ORIGINAL ARTICLE Facial morphology of Finnish children with and without developmental hip dysplasia using 3D facial templates SB Hanis CH Kau NM Souccar JD English P Pirttiniemi M Valkama V Harila Authors' affiliations: S.B. Hanis, J.D. English, Department of Orthodontics, The University of Texas Dental Branch at Houston, Houston, TX, USA C.H. Kau, N.M. Souccar, Department of Orthodontics, The University of Alabama at Birmingham, Birmingham, AL, USA P. Pirttiniemi, V. Harila, Department of Oral and Orthodontics, Oulu University Hospital, University of Oulu, Oulu, Finland M. Valkama, Department of Pediatrics and Adolescence, Oulu University Hospital, University of Oulu, Oulu, Finland Correspondence to: Dr Chung How Kau Department of Orthodontics University of Alabama at Birmingham 1919 7th Avenue South SDB 305 Birmingham, AL 35294, USA E-mail: ckau@uab.edu Structured Abstract Authors – Hanis SB, Kau CH, Souccar NM, English JD, Pirttiniemi P, Valkama M, Harila V Background – Developmental dysplasia of the hip (DDH) is a condition that affects the femoral head and the acetabulum and leads to hip subluxation and dislocation. Infants with DDH are usually treated using splints that immobilize their hip joint and are forced on their back for long periods of time. The link between positioning and facial asymmetries is poorly understood. Objective – To compare the facial morphologies of children with DDH to a group of healthy controls. Subjects and methods – Fifty-six Finnish patients born with DDH were matched on the basis of gender and age to a control group. Three-dimensional surface images were captured using the 3dMDface system. Using RF6 PP2 software, anthropometric landmarks were plotted and used to calculate asymmetry based on 3D co-ordinates in a reference framework. Results – There was statistically significant difference between all paired facial shells. Relative to the control group, DDH boys and girls presented a chin-point deviation to the right, a more prominent left orbital ridge, a more protrusive nose and upper lip. The gender-specific subgroups show a similarity of 66.54 and 65.22% in girls and boys, respectively. Conclusions – Patients with DDH present a facial asymmetry when compared to healthy controls. Gender characteristics are marked whether subjects are affected with DDH or not. Three-dimensional surface imaging is a powerful diagnostic and research tool. Key words: 3D analysis; asymmetry; face; hip Introduction Developmental dysplasia of the hip (DDH) is a condition that affects the femoral head and the acetabulum and leads to hip subluxation and dis- location. It occurs one in 1000 births and affects more girls than boys (1, 2). The left hip is involved in the majority of cases (60%). This incidence is in relation to the most common intrauterine position, the left occiput anterior, which is believed to push the left hip against the motherÕs lum- Dates: Accepted 5 August 2010 To cite this article: Hanis SB, Kau CH, Souccar NM, English JD, Pirttiniemi P, Valkama M, Harila V: Facial morphology of Finnish children with and without developmental hip dysplasia using 3D facial templates Orthod Craniofac Res 2010;13:229–237 Ó 2010 John Wiley & Sons A/S