Diastasis of the rectus abdominis muscle

Diastasis of the rectus abdominis muscle (Latin: diastasis recti abdominis) is a condition characterized by excessive separation of the two bellies of the rectus abdominis muscle resulting from stretching of the linea alba, the connective tissue structure running along the midline of the body. This phenomenon most often occurs in pregnant and postpartum women, but it can also affect men and people with obesity or chronically increased intra-abdominal pressure. Muscle separation is not solely an aesthetic problem — it affects trunk stabilization, the function of the abdominal organs, and the biomechanics of the entire musculoskeletal system.

Diastasis of the rectus abdominis muscle – causes

The development of diastasis of the rectus abdominis muscle is primarily caused by chronic stretching and weakening of the linea alba, which physiologically keeps both muscles in the midline. The most important etiological factors include:

pregnancy and the postpartum period – the enlarging uterus increases intra-abdominal pressure, and hormones (e.g., relaxin) reduce connective tissue tension,
abdominal obesity – chronic pressure on the abdominal wall,
intense, improper abdominal muscle training – especially exercises that increase intra-abdominal pressure (e.g., classic „sit-ups”),
chronic cough or constipation – repeated increases in intra-abdominal pressure,
genetic factors – congenital weakness of connective tissue.

It is worth emphasizing that diastasis does not constitute a hernia; however, in advanced cases it may coexist with a linea alba or umbilical hernia. Dysfunction of the deep muscles (the transverse abdominal muscle), which stabilize the trunk and relieve the linea alba, also plays an important role.

Separation of the rectus abdominis muscle – how to recognize

Diagnosis of diastasis of the rectus abdominis is based on clinical examination and – if necessary – imaging diagnostics. The basic method is a palpation test performed in the supine position:

the patient lifts the head and shoulders (as with a gentle curl),
the examiner assesses the width of the gap between the muscles in the midline,
the measurement is often expressed in finger widths (e.g. >2 cm is considered pathological).

Additionally, the following are used:

abdominal wall ultrasound (US) – precise assessment of the width of the diastasis and the condition of the linea alba,
functional testing – assessment of deep muscle tone and trunk stabilization.

In clinical practice the location of the diastasis is important:

above the umbilicus,
at the level of the umbilicus,
below the umbilicus.

The diastasis can be symmetrical or asymmetrical, and its width and depth influence the choice of therapeutic management.

Diastasis of the rectus abdominis – symptoms

Symptoms of diastasis of the rectus abdominis include both aesthetic and functional aspects. The most commonly observed are:

Local symptoms:

visible protrusion along the midline of the abdomen (the so-called "cone" during muscle contraction),
laxity and loss of abdominal wall tone,
difficulty reducing abdominal circumference despite physical activity.

Functional symptoms:

weakened trunk stabilization,
pain in the lumbar spine,
postural disorders (e.g., increased lumbar lordosis),
a sensation of "lack of control" over the abdominal muscles.

Associated symptoms:

pelvic floor dysfunctions (e.g., urinary incontinence),
digestive problems (feeling of bloating, discomfort),
reduced physical capacity.

In advanced cases, complications such as hernias may occur, which require further diagnostic evaluation.

Diastasis of the rectus abdominis muscle – when to see a specialist

A specialist consultation (urogynecological physiotherapist, physician, or surgeon) is indicated in situations where:

the separation exceeds 2–2.5 cm and persists beyond 3–6 months postpartum,
there is pain in the spine or pelvis,
symptoms of pelvic floor dysfunction occur,
an increasing bulge along the midline is visible,
a hernia is suspected.

Therapeutic management primarily includes targeted physiotherapy, focused on activation of the transversus abdominis muscle and improving motor control. In selected cases, the following are used:

manual therapy and fascial tissue work,
central stabilization (core stability) training,
breathing therapy.

In advanced cases or those resistant to conservative treatment, surgical treatment (e.g., repair of the linea alba) is considered.

In the practice of aesthetic and functional medicine, support for therapy may include procedures that improve tissue quality and skin tension, such as:

microneedling radiofrequency – collagen stimulation and improvement of tissue tension,
HIFU technologies – noninvasive tissue tightening/densification,
regenerative therapies (e.g., platelet-rich plasma) – supporting the remodeling of connective tissue.

Therapy selection should always be individualized and based on the degree of separation and the clinical symptoms.