The hindlimb development lags behind forelimb development by 1–2 days. Function
As the femur is the only bone in the thigh, it serves as an attachment point for all the muscles that exert their force over the hip and knee joints. Some biarticular muscles – which cross two joints, like the gastrocnemius and plantaris muscles – also originate from the femur. In all, 23 individual muscles either originate from or insert onto the femur. In cross-section, the thigh is divided up into three separate fascial compartments divided by fascia, each containing muscles. These compartments use the femur as an axis, and are separated by tough connective tissue membranes (or septa). Each of these compartments has its own blood and nerve supply, and contains a different group of muscles. These compartments are named the anterior, medial and posterior fascial compartments. Muscle attachments
Clinical significance
Fractures
A femoral fracture that involves the femoral head, femoral neck or the shaft of the femur immediately below the lesser trochanter may be classified as a hip fracture, especially when associated with osteoporosis. Femur fractures can be managed in a pre-hospital setting with the use of a traction splint. Diversity among animals
In primitive tetrapods, the main points of muscle attachment along the femur are the internal trochanter and third trochanter, and a ridge along the ventral surface of the femoral shaft referred to as the adductor crest. The neck of the femur is generally minimal or absent in the most primitive forms, reflecting a simple attachment to the acetabulum.
Meatal stenosis, making it more difficult or even impossible to urinate, may also occur.On the non-genital skin, the disease may manifest as porcelain-white spots with small visible plugs inside the orifices of hair follicles or sweat glands on the surface. Thinning of the skin may also occur. Psychological effect
Distress due to the discomfort and pain of lichen sclerosus is normal, as are concerns with self-esteem and sex. Counseling can help.According to the National Vulvodynia Association, which also supports women with lichen sclerosus, vulvo-vaginal conditions can cause feelings of isolation, hopelessness, low self-image, and much more. Some women are unable to continue working or have sexual relations and may be limited in other physical activities. Depression, anxiety, and even anger are all normal responses to the ongoing pain LS patients experience. Pathophysiology
Although it is not clear what causes LS, several theories have been postulated. Lichen sclerosus is not contagious; it cannot be caught from another person.Several risk factors have been proposed, including autoimmune diseases, infections and genetic predisposition. There is evidence that LS can be associated with thyroid disease. Genetic
Lichen sclerosus may have a genetic component. A high correlation of lichen sclerosus has been reported between twins and between family members. Autoimmunity
Autoimmunity is a process in which the body fails to recognize itself and therefore attacks its own cells and tissue. Specific antibodies have been found in LS. Furthermore, there seems to be a higher prevalence of other autoimmune diseases such as diabetes mellitus type 1, vitiligo, alopecia areata, and thyroid disease.