200px Functional anatomy The<unk>  joint, is a ball-and-socket joint. The femur connects at the acetabulum of the pelvis and projects laterally before angling medially and inferiorly to form the knee. Although this joint has three degrees of freedom, it is still stable due to the interaction of ligaments and cartilage. The labrum lines the circumference of the acetabulum to provide stability and shock absorption. Articular cartilage covers the concave area of acetabulum, providing more stability and shock absorption. Surrounding the entire joint itself is a capsule secured by the tendon of the psoas muscle and three ligaments. The iliofemoral, or Y, ligament is located anteriorly and serves to prevent<unk>  hyperextension. The pubofemoral ligament is located anteriorly just underneath the iliofemoral ligament and serves primarily to resist abduction, extension, and some external rotation. Finally the ischiofemoral ligament on the posterior side of the capsule resists extension, adduction, and internal rotation. When considering the biomechanics of<unk> s, it is important to examine the mechanical loads the<unk>  experiences during low energy falls. Biomechanics The<unk>  joint is unique in that it experiences combined mechanical loads. An axial load along the shaft of the femur results in compressive stress. Bending load at the neck of the femur causes tensile stress along the upper part of the neck and compressive stress along the lower part of the neck. While osteoarthritis and osteoporosis are associated with bone fracture as we age, these diseases are not the cause of the fracture alone. Low energy falls from standing are responsible for the majority of fractures in the elderly, but fall direction is also a key factor. Elderly tend to fall to the side as instead of forward, and the lateral<unk>  and strikes the ground first. During a sideways fall, the chances of<unk>  see a 15-fold and 12-fold increase in elderly males and females, respectively. Neurological factors Elderly individuals are also predisposed to<unk> s due to many factors that can compromise proprioception and balance, including medications, vertigo, stroke, and peripheral neuropathy.
Hip fracture
Osteoarthritis
Bosworth fracture
Greater trochanteric pain syndrome
Hume fracture
Hernia
Holdsworth fracture
Avascular necrosis