Illustration of a hip bone fracture, showing a fracture of the thigh bone (femur) between the femoral head and the trochanters, called femoral neck fracture.

Medical illustration showing a cube section through the dermal (skin) layers comparing a normal follicle with hair and a similar follicle without hair representing baldness or alopecia. Labels identify the cut section of skin, follicle with hair, and follicle without hair.

Medical illustration showing the primary reconstruction of the breast following a total mastectomy, sagittal view (cutaway section viewed from the side), with two side-by-side comparative views of the thorax wall. Seen here are the chest wall after a mastectomy (left) and a reconstructed breast with a subcutaneous implant (right).

Medical illustration depicting the location of axillary (armpit) lymph nodes typically removed during radical breast cancer treatment surgery.

Medical illustration of obstructive sleep apnea. Upper airway blockage is seen in a sagittal section (cutaway side view) through the back of the mouth, showing the relaxed soft tissues of the tongue and posterior throat displacing posteriorly (backwards), closing off the airway when the person is lying down.

Medical illustration showing the chambers of the heart from an anterior (front) view. Labels identify the right chambers, including the right atrium and right ventricle, as well as the left chambers, including the left atrium and left ventricle.

Medical illustration of coronary artery disease (left to right): orientation of the heart and coronary arteries, anterior view; detail of normal blood flow through the left anterior descending (LAD) coronary artery, cutaway view; detail of the LAD coronary artery with plaque slowing blood flow through the vessel, cutaway view.

Medical illustration depicting a mastectomy. Shown here are the incision (A) and the surgical procedure of removing breast tissue and lymph nodes (B).

Illustration of a digital (finger) rectal examination, lateral cutaway view.

Illustration of thrombosis, comparing normal blood flow through an artery (left); and an artery with a thrombus (blood clot) impeding blood flow through the vessel (right).

Illustration of the normal anterior cruciate ligament (ACL), anteromedial view. Shown are a bent right knee joint (left) and a detail of the femur, tibia, and ACL (right).

Illustration of a torn anterior cruciate ligament (ACL), anteromedial view. Shown are a bent right knee joint (left) and a detail of the torn ACL.

Illustration comparing blood flow through a normal artery (left) versus obstructed blood flow due to atherosclerotic plaque (right).

Illustration of the chorionic villi of the placenta. Shown are the placenta and fetus in utero, sagittal view (left), and a detail of the maternal-fetal blood supply through the umbilical cord and chorionic villi (right).

Illustration of adhesive capsulitis of the shoulder, showing inflammation and thickening of the right shoulder capsule, anterior view.

Illustration of carbon monoxide binding to hemoglobin in a red blood cell (RBC) during respiration (breathing). Hemoglobin carries oxygen and carbon dioxide in an RBC (left), but when carbon monoxide binds tightly to hemoglobin, oxygen and carbon dioxide can no longer be carried (right).

Illustration of colorectal cancer with metastases in the liver, anterior cutaway view. Labels identify tumors in the rectum and liver. Organs shown include the liver, large intestine (colon), stomach, small intestine, pancreas, and appendix.

Illustration of coronary artery disease, showing the heart and details of a coronary artery with various degrees of blockage.

Illustration showing the tender points associated with fibromyalgia syndrome (FMS) on a female figure. These points trigger extreme pain when pressed.

Illustration showing the tender points associated with fibromyalgia syndrome (FMS) on a male figure. These points trigger extreme pain when pressed.