A Chicken Model for Acoustic Detection of Developmental Hip Dysplasia

Developmental dysplasia of the hip (DDH) is the instability of the hip joint, which occurs in 36 to 64 per 1000 births in the United States. Approximately one in five hundred infants are born with a dislocated hip where the femoral head lies outside the acetabulum [1]. If not detected and treated before six months of age, dislocation can lead to abnormal gait, limb length differences, issues in posture, chronic pain, and joint stress. If DDH goes unrecognized, patients often require invasive procedures such as open reduction or hip reconstruction, which unfortunately do not have a high success rates [2]. Pediatricians often use the “Barlow and Ortolani maneuvers” to detect hip dysplasia in infants. These techniques are highly skill dependent and lack sensitivity with only 54% accuracy in detecting DDH and, therefore, developing new screening methods would be beneficial [1]. Imaging techniques such as ultrasound and radiography can be used to validate the results of the Barlow and Ortolani tests but may be expensive, while ionizing x-ray exposure can be dangerous to infants [3]. If proven to be adequately predictive, a non-invasive bedside technique based on audible sound transmission would be a possible option to detect DDH because it would be safe, comfortable, inexpensive, and easy to use. Previous studies used this approach to detect DDH on simplified benchtop and pig models, which suggested that acoustic detection could be used to indicate dislocation [4]–[7]. The current study focuses on applying a similar method for DDH detection in a chicken model. Because the chicken joint is similar to a baby joint, it is a possible model to initially demonstrate potential utility [8].