Sternum

You have a flat bone in your chest.

It is called the breastbone. It sits in the middle of your chest. This bone helps protect your heart and lungs.

It connects to your ribs. The bone has three main parts. The top part is wide. The middle part is the longest. The bottom part is pointy.

It is a very important bone for your body.

The sternum is a long, flat bone in your chest.

Most people call it the breastbone. It sits right in the middle of your chest. This bone helps protect your heart and lungs.

It connects to your ribs using cartilage. Cartilage is a tough, flexible material.

The sternum has three main parts. The top part is the manubrium. It is wide and shaped like a handle.

The middle part is the body. It is the longest part of the bone. The bottom part is the xiphoid process. This part is small and pointy.

This bone grows in a special way. It starts as two soft bars of cartilage. These bars fuse together in the middle. Then, they turn into hard bone through ossification. This is a way that bone forms. This process starts before you are born. The different parts finish growing at different times. For example, the bottom part may not finish until you are much older.

Sometimes, doctors use the sternum to find bone marrow. Bone marrow is the soft stuff inside bones. It is often used for medical tests.

The sternum is a long, flat bone in the center of your chest.

Many people call it the breastbone. It sits right in the middle of the front of your chest. This bone is one of the largest flat bones in your body. It works like a shield for your heart and lungs.

It also protects your major blood vessels from injury. The bone connects to your ribs using pieces of cartilage. This cartilage helps form your rib cage.

Your sternum has three main parts that work together. The top part is called the manubrium, which is Latin for "handle."

It is a wide, four-sided shape at the top of your chest. The middle part is the body, also called the gladiolus. This is the longest part of the entire bone. The bottom part is the xiphoid process. This is a small, pointed piece at the very end. The whole bone is shaped roughly like a necktie.

This bone grows through a process called ossification.

It begins as two soft bars of cartilage on the left and right sides. These two bars eventually fuse together in the middle. The bone forms from six different centers of growth. One center forms the manubrium and one forms the xiphoid process. Four centers form the body of the bone. These centers appear in a specific order as you grow. The manubrium and the first part of the body begin to harden during the sixth month of life in the womb.

Growth happens at different speeds for different people.

The different pieces of the body start to join together around puberty. By the age of 25, all the parts are usually united. The xiphoid process can take a very long time to finish. It might join the body before age 30, but sometimes it stays separate even in old age. Females often finish growing this bone earlier than males do. Some people might even have a small hole in their bone called a sternal foramen.

Doctors sometimes look at the sternum to help patients.

Because the bone contains bone marrow, it is a place for a bone marrow biopsy. This is a medical test used to check health. The sternum can also be injured in accidents. A person might fracture the bone if they hit a steering column in a car. In some surgeries, doctors must cut the bone open to reach the heart. This is called a median sternotomy. They then use wires or plates to hold the bone together while it heals.

The sternum, often called the breastbone, is a long, flat bone located in the center of the chest.

It serves a vital role in the human body by forming the front of the rib cage. This structure helps protect delicate organs like the heart, lungs, and major blood vessels from injury. The sternum is one of the largest and longest flat bones in the human body. Its name comes from the Ancient Greek word *stérnon*, which means "chest."

The sternum is composed of three distinct anatomical regions. At the very top is the manubrium, a term derived from Latin meaning "handle."

This part is broad and quadrangular, featuring a central indentation called the suprasternal notch. Below the manubrium lies the body, or gladiolus, which is the longest part of the bone. The body is flat and features three transverse ridges on its front surface. Finally, the lowest part is the xiphoid process, a small and pointed structure at the inferior end.

These three parts connect to the rest of the skeletal system through specific joints. The manubrium supports the clavicles, or collarbones, at its top edges. It also joins with the costal cartilages of the first one and a half pairs of ribs. The body of the sternum connects to the second through the sixth ribs via costal cartilages. The sternal angle is a crucial landmark located where the manubrium meets the body. This angle is where the second rib attaches, making it easy for doctors to locate during physical exams.

Development of the sternum involves a complex process called ossification, where cartilage turns into bone.

It begins as two cartilaginous bars on the left and right sides of the chest. These bars eventually fuse together along the middle to create a single bone. The sternum forms from six different ossification centers. One center forms the manubrium, one forms the xiphoid process, and four centers form the body. These centers appear in a specific sequence, starting in the sixth month of fetal life.

Growth patterns for the sternum vary based on age and biological sex. The ossification centers in the body begin to fuse around the time of puberty. By age 25, most of these segments have fully united into one bone. Females generally complete this development earlier than males. The xiphoid process is the slowest to finish, sometimes remaining ununited even into old age. Interestingly, the xiphoid process might not join the main body until after a person reaches age 40.

While most people have a standard sternum, some anatomical variations exist. Between 2.5% and 13.5% of people have a sternal foramen, which is a small hole in the lower body. This hole is present from birth and is often located to the left or right of the center.

Other rare variations include the presence of small bones called episternal ossicles or a vertical fissure known as *fissura sterni*. These variations are usually harmless, though they can be noted by doctors during medical procedures.

Because of its location and composition, the sternum is significant in clinical medicine. The bone contains highly vascular tissue, meaning it has a rich blood supply. This makes it a useful site for a bone marrow biopsy, especially for patients with a high BMI. In major surgeries, such as cardiothoracic surgery, doctors may perform a median sternotomy. This involves cutting the sternum open to access the heart. Surgeons then use wire cerclage or metal plates and screws to fix the bone back together.