Bone Retroversion: Attachment of a bone in which its head and neck is rotated excessively backward.Bone and Bones: A specialized CONNECTIVE TISSUE that is the main constituent of the SKELETON. The principle cellular component of bone is comprised of OSTEOBLASTS; OSTEOCYTES; and OSTEOCLASTS, while FIBRILLAR COLLAGENS and hydroxyapatite crystals form the BONE MATRIX.Uterine Retroversion: A condition in which the UTERUS is found tilted backward toward the spine. The uterus is more commonly found in a straight vertical or anteverted (tipped forward) position. Although retroverted uterus is a normal variant position without symptoms, it is sometimes associated with pain, discomfort and other pregnancy complications.Acetabulum: The part of the pelvis that comprises the pelvic socket where the head of FEMUR joins to form HIP JOINT (acetabulofemoral joint).Ischium: One of three bones that make up the coxal bone of the pelvic girdle. In tetrapods, it is the part of the pelvis that projects backward on the ventral side, and in primates, it bears the weight of the sitting animal.Pelvic Bones: Bones that constitute each half of the pelvic girdle in VERTEBRATES, formed by fusion of the ILIUM; ISCHIUM; and PUBIC BONE.Humerus: Bone in humans and primates extending from the SHOULDER JOINT to the ELBOW JOINT.Femoracetabular Impingement: A pathological mechanical process that can lead to hip failure. It is caused by abnormalities of the ACETABULUM and/or FEMUR combined with rigorous hip motion, leading to repetitive collisions that damage the soft tissue structures.Hip Joint: The joint that is formed by the articulation of the head of FEMUR and the ACETABULUM of the PELVIS.Hip Dislocation: Displacement of the femur bone from its normal position at the HIP JOINT.Hip Dislocation, Congenital: Congenital dislocation of the hip generally includes subluxation of the femoral head, acetabular dysplasia, and complete dislocation of the femoral head from the true acetabulum. This condition occurs in approximately 1 in 1000 live births and is more common in females than in males.Bone Remodeling: The continuous turnover of BONE MATRIX and mineral that involves first an increase in BONE RESORPTION (osteoclastic activity) and later, reactive BONE FORMATION (osteoblastic activity). The process of bone remodeling takes place in the adult skeleton at discrete foci. The process ensures the mechanical integrity of the skeleton throughout life and plays an important role in calcium HOMEOSTASIS. An imbalance in the regulation of bone remodeling's two contrasting events, bone resorption and bone formation, results in many of the metabolic bone diseases, such as OSTEOPOROSIS.Brachial Plexus Neuropathies: Diseases of the cervical (and first thoracic) roots, nerve trunks, cords, and peripheral nerve components of the BRACHIAL PLEXUS. Clinical manifestations include regional pain, PARESTHESIA; MUSCLE WEAKNESS, and decreased sensation (HYPESTHESIA) in the upper extremity. These disorders may be associated with trauma (including BIRTH INJURIES); THORACIC OUTLET SYNDROME; NEOPLASMS; NEURITIS; RADIOTHERAPY; and other conditions. (From Adams et al., Principles of Neurology, 6th ed, pp1351-2)Osteotomy: The surgical cutting of a bone. (Dorland, 28th ed)Torsion Abnormality: An abnormal twisting or rotation of a bodily part or member on its axis.Radiostereometric Analysis: Methods for performing three-dimensional measurement and motion analysis using stereoscopic radiographs.Bone Density: The amount of mineral per square centimeter of BONE. This is the definition used in clinical practice. Actual bone density would be expressed in grams per milliliter. It is most frequently measured by X-RAY ABSORPTIOMETRY or TOMOGRAPHY, X RAY COMPUTED. Bone density is an important predictor for OSTEOPOROSIS.Birth Injuries: Mechanical or anoxic trauma incurred by the infant during labor or delivery.