Lack of full passive range of motion (restrictions in flexion, extension, or other movements) of the hip joint resulting from structural changes of non-bony tissues, such as muscles, tendons, ligaments, joint capsules and/or skin. The phenotype is Hip contracture (HP_0003273). Also known as: Flexion contracture of hips, Flexion contractures of hips, Hip contractures, Hip flexion contractures.