What does diastasis mean in medical terms?: A complete guide

September 22, 2025 •

4 min read

In medical science, the term diastasis refers to an abnormal separation of parts of the body that are normally joined together. For many, the first encounter with this word is in the context of pregnancy, which is the most common cause of what does diastasis mean in medical terms discussions regarding the abdominal muscles. This condition affects a significant portion of postpartum women, though it can occur in others too.

Quick Summary

Diastasis is a medical term for the separation of two normally connected body parts, most commonly the abdominal muscles known as diastasis recti. It can result from pregnancy, obesity, or other factors and is often identified by a ridge-like bulge along the midline of the abdomen.

Key Points

Core Definition: Diastasis refers to the abnormal separation of body parts, especially muscles or bones, that are typically joined.
Diastasis Recti: The most common form, this involves the separation of the rectus abdominis muscles, creating a bulge in the abdomen.
Primary Causes: Pregnancy, obesity, and improper exercise techniques are leading causes of diastasis recti.
Signs and Symptoms: A tell-tale sign is a visible ridge or 'doming' down the center of the abdomen when straining.
Management: Treatment options range from physical therapy and core strengthening exercises to surgical repair for severe cases.
Not Just Abdominal: The term can also describe separations in other areas, such as the tibiofibular joint in the lower leg.

Understanding the Core Concept of Diastasis

At its most fundamental level, diastasis is derived from the Greek word diistanai, meaning 'to separate'. It is a broad medical term that can apply to various parts of the body, not just the abdomen. While diastasis recti is the most widely recognized form, the term can also refer to the separation of bones, such as a tibiofibular syndesmosis diastasis, which involves the lower leg bones, or a diastasis of the pubic symphysis, which can occur during childbirth.

Diastasis Recti: The Most Common Form

Diastasis recti, or abdominal separation, is a condition where the right and left halves of the outermost abdominal muscle, the rectus abdominis (the 'six-pack' muscles), spread apart. The connective tissue joining them, the linea alba, stretches and thins. This stretching causes a visible ridge or bulge down the midline of the stomach, especially when straining or engaging the abdominal muscles.

Causes and Risk Factors for Diastasis Recti

Diastasis recti is not a hernia, but it is caused by internal pressure that forces the abdominal muscles and connective tissue to stretch. Several factors increase the risk of developing this condition:

Pregnancy: This is the most common cause, with the expanding uterus putting significant pressure on the abdominal wall. Multiple pregnancies and carrying multiples increase the risk.
Infancy: Diastasis recti can be congenital in newborns, especially premature infants, though it often resolves on its own.
Obesity: Excessive abdominal fat and weight fluctuations can place strain on the linea alba.
Improper Exercise: Certain exercises, like heavy lifting with poor form or intense abdominal workouts that increase intra-abdominal pressure, can contribute.
Aging: As people age, the elasticity of connective tissues can decrease, making them more susceptible to separation.

Diagnosing and Managing Diastasis Recti

A physical exam is the primary way healthcare providers diagnose diastasis recti. A simple self-test can also give you an indication:

Lie on your back with your knees bent and feet flat on the floor.
Place your fingers just above or below your belly button, pointing towards your pelvis.
Gently lift your head and shoulders, as if performing a mini-crunch.
If you feel a gap of two or more finger-widths between your rectus abdominis muscles, it is likely you have diastasis recti.

Management strategies vary depending on the severity, from conservative approaches to surgical intervention.

Physical Therapy: Targeted exercises, often guided by a pelvic floor specialist, focus on strengthening the deep core muscles, such as the transverse abdominis, to provide support and help close the gap.
Lifestyle Modifications: Avoiding activities that increase intra-abdominal pressure, such as heavy lifting or certain exercises (e.g., crunches), is often recommended.
Surgery: In severe, symptomatic cases, or when conservative methods fail, a surgical procedure called abdominoplasty (tummy tuck) may be used to repair the muscle separation.

Comparing Different Types of Diastasis


Feature	Diastasis Recti (Abdominal)	Tibiofibular Diastasis (Ankle/Lower Leg)
Location	Midline of the abdomen, separating the rectus abdominis muscles.	Between the tibia and fibula bones in the lower leg, near the ankle joint.
Cause	Pregnancy, obesity, improper exercise, chronic straining.	Traumatic injury, such as a high ankle sprain, often involving torn ligaments.
Symptoms	Abdominal bulging, low back pain, pelvic floor dysfunction, poor posture.	Pain, swelling, instability in the ankle, difficulty bearing weight.
Treatment	Physical therapy, lifestyle changes, surgery (abdominoplasty).	Immobilization (boot/cast), rehabilitation, surgery to stabilize the joint.

The Broader Medical Context of Diastasis

It's important to remember that 'diastasis' is a descriptive term for a separation, and its implications depend entirely on the body part involved. For example, a diastasis in a newborn's skull, though rare, would have vastly different clinical significance and treatment than the common postpartum abdominal separation.

Physiological vs. Pathological Diastasis

Some forms of diastasis are temporary and physiological. In the case of pregnancy, the stretching of the linea alba is a normal and necessary adaptation to accommodate the growing fetus. Problems arise when this tissue fails to recoil effectively after birth, leading to a persistent pathological diastasis.

Conversely, a diastasis resulting from a traumatic injury, such as a car accident causing separation of the pubic symphysis, is always pathological and requires immediate medical attention. It is crucial to understand the context in which the term is used to determine its severity and required course of action.

Conclusion

In summary, what does diastasis mean in medical terms is an abnormal separation of normally joined body parts. While often associated with the abdominal muscles in postpartum women (diastasis recti), it is a broader term encompassing various anatomical separations. Understanding the specific location and cause of the separation is key to proper diagnosis and treatment, which can range from targeted exercises to surgical repair. Consult with a healthcare provider for an accurate diagnosis and treatment plan if you suspect you have diastasis.

For more detailed medical information, consider exploring resources from the National Institutes of Health.

Frequently Asked Questions

No, diastasis is not a hernia. A hernia occurs when an organ pushes through an opening in the muscle or tissue that holds it in place. Diastasis, particularly diastasis recti, is a separation of the abdominal muscles themselves, though it can sometimes increase the risk of a hernia.

Yes, while more commonly associated with women after pregnancy, men can also develop diastasis recti. Causes in men can include significant weight gain, obesity, improper lifting techniques, or genetics.

You can perform a simple self-check by lying down, lifting your head and shoulders, and using your fingers to feel for a gap along the midline of your abdomen. A gap of more than two finger-widths is often considered diastasis. A medical professional can confirm the diagnosis.

In some cases, especially in newborns, diastasis recti can resolve on its own. For adults, particularly postpartum women, the condition may improve with conservative management like targeted physical therapy and lifestyle adjustments, though complete closure of the gap isn't always achieved without surgery.

You should generally avoid exercises that increase intra-abdominal pressure and cause bulging, such as traditional crunches, sit-ups, and planks. High-impact exercises can also put additional strain on the abdominal wall. A physical therapist can guide you toward safer alternatives.

Diastasis recti itself is usually painless. However, it can lead to other issues that cause pain, such as lower back pain due to weakened core support, poor posture, and pelvic floor dysfunction.

For many people, physical therapy is very effective at strengthening the deep core muscles and improving the functional symptoms associated with diastasis. It may not completely close a large gap, but it can significantly improve core stability and resolve related issues like back pain.