Diaphragm Anatomy

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The Diaphragm in Human Body

All living organisms require energy to meet down their daily requirements. This energy is derived from the breakdown of nutrient molecules like glucose. Catabolic reactions are the reactions in which glucose is broken down into carbon dioxide and water in the presence of oxygen and energy is released in the form of ATP. Breathing is the process that helps us to get the oxygen we need and release out carbon dioxide. The diaphragm plays an important role in breathing. It helps in the contraction and relaxation of lungs that help them to increase their surface area. It is present at the base of the chest and is separated from the abdomen. 

Diaphragm Definition

Here we will define diaphragm. The diaphragm in human body is a group of thin skeletal muscles that sits at the base of the chest. This diaphragm also separates the abdomen from the chest. When we inhale the diaphragm contracts and flattens. This in turn helps to create a vacuum. The vacuum effect then helps to pull the air into the lungs. When the diaphragm relaxes, the air from the lungs is pushed out and this helps us to exhale the carbon dioxide. This gives us an idea about the diaphragm meaning. 

Diaphragm Anatomy

The diaphragm plays an important role in the expulsive actions of the body such as coughing, sneezing, crying. Thus, these are the functions that the diaphragm exhibits other than helping in respiration. The movement of the diaphragm is controlled by the phrenic nerve. The rubber arcing spring, coil spring, and flat spring, as well as the silicone wide seal rim15, are types of diaphragms.

The diaphragm has three openings and these openings help to provide a space from which certain structures can pass. These openings are: 

  • Oesophagal Opening: Through this opening, the oesophagus and the vagus nerve passes. These structures control the digestive system. 

  • Aortic Opening: Aorta is the main artery of the body that transports blood from the heart. Through this opening, the aorta and the thoracic duct pass. 

  • Caval Opening: Through this opening, the inferior vena cava passes. It is the vein that transports blood to the heart. 

This gives us an idea about the diaphragm anatomy. Now we will look for a diaphragm diagram. 

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What is Diaphragm Function?

The diaphragm is the main part of the human respiratory system along with the lungs. Let’s learn about the human respiratory system and then about the role of diaphragm.  

Respiratory passage: Through this passage, the air travels from outside to the lungs. The passage consists of nostrils, nasal passages, pharynx, larynx, trachea, bronchi and lungs. We will learn about the mechanism of breathing now. 


In this process, fresh air enters the lungs. The inflow or inhalation of air is known as inhalation. A pressure gradient is created between the lungs and this helps in the movement of air in and out of the body. The pressure gradient is defined as the pressure that is created so that the gases flow from higher concentration to their lower concentration. As we know that the pressure of oxygen outside the body is high and inside the lungs is low, so the oxygen diffuses into the lungs that are from a higher concentration to its lower concentration. The diaphragm plays a great role in this process. The diaphragm muscles get contracted, due to this the diaphragm becomes flat and this helps to increase the volume of the thoracic cavity in the anteroposterior axis. This increase in the volume of the thoracic cavity leads to an increase in the pulmonary cavity. This then decreases the pressure within the pulmonary cavity and this causes the air from the atmosphere to enter the lungs as air moves from higher pressure to lower pressure. The external intercostal muscles are present between the ribs. When these muscles contract it increases the volume of the thoracic cavity by lifting the ribs and sternum up and outward.


By this process, carbon dioxide is expelled outside the body through the lungs. It is also known as outflow or exhalation of air. When the pressure within the lungs is more than the atmospheric pressure, then the air moves out of the lungs. The diaphragm plays an important role here also. When the diaphragm relaxes, it returns to its original position and thus the volume of the thoracic cavity is decreased. The decrease in thoracic volume results in expelling out the air from the lungs. The decrease in volume of the thoracic cavity leads to the decrease in the pulmonary cavity and this causes the pressure in the pulmonary cavity to increase and thus creating a zone of high pressure as compared to the atmospheric pressure. So air moves from the lungs to the atmosphere. 

Diaphragm Diseases

As we know the diaphragm in human body is a very important organ to the human body. It plays a major role in breathing. But some conditions can lead to dysfunctioning of the diaphragm. Some of these conditions are listed below. 

Hiatal Hernia

This condition happens when the upper part of the stomach bulges out from the oesophagal opening of the diaphragm. These can be caused by age-related changes in the diaphragm. Some injuries or birth defects can also cause a hiatal hernia. It can also occur by straining, lifting heavy weights or from the chronic pressure created around the muscles from coughing. Obese people suffer more from this condition. Some symptoms of hiatal hernia are acid reflux, chest burn and sometimes chest pain that radiates to the back. Surgery is required for the larger Hiatal hernias. 

Diaphragmatic Hernia

This happens when anyone's abdominal organ is bulged out from the chest through the opening of the diaphragm. When this condition is present from birth it is known as a congenital diaphragmatic hernia. Injuries from accidents can also cause this hernia. The symptoms may include rapid breathing or difficulty in breathing. The heart rate is also increased and the skin appears bluish. 

Phrenic Nerve Damage

The phrenic nerve gets damaged due to surgery, spinal cord conditions and autoimmune diseases. Certain illnesses and neuromuscular disorders also result in this condition. Sometimes due to this the diaphragm can be paralyzed or dysfunctional. 

Diaphragm Health

Hence, to protect our diaphragm from these diseases and to lead a life with a healthy diaphragm some points can be kept in mind: 

  • To eat smaller portions of food. To properly chew the food. 

  • To stretch and warm-up before exercising. 

  • To avoid the food that may lead to heartburns or acid refluxes. 

  • To exercise within our limits.

  • To do certain exercises that strengthen the diaphragm. 

FAQ (Frequently Asked Questions)

1. What do you know about the Nervous Regulation of Respiration? 

Answer: Breathing is an involuntary process. The neural and nervous system has various respiratory centres that are present in the brain. Medulla oblongata and pons from the respiratory centre. In the medulla region of the hindbrain. It can cause inspiration or expiration of breathing and this can help in regulating the breathing rhythm. The pneumatic centre is present in the pons region. This helps in moderating the functions of the respiratory rhythm centre. 

2. What is Carbon Monoxide Poisoning?

Answer: This occurs when a person is sleeping in a closed room with a lamp burning. Due to the burning of wood, there is very little oxygen and high carbon monoxide. The affinity for carbon monoxide is much higher than that of oxygen. So carbon monoxide gets bound to the haemoglobin and this reduces the amount of oxygen in the blood and hence a person can die due to this.