Titolo della tesi: Outcomes funzionali della tecnica mini-invasiva MISAR nel trattamento della diastasi dei muscoli retti dell’addome.
Progetto di Ricerca per il Dottorato in “Tecnologie Avanzate in Chirurgia” (XXXV ciclo)
“Outcomes funzionali della tecnica mini-invasiva MISAR nel trattamento della diastasi dei muscoli retti dell’addome”
Relatore: Prof. E. Fiori; Correlatore: Prof. G. Cavallaro
Dottoranda: Dott.ssa Antonietta De Gori
Rectus diastasis (RD) is an acquired condition in which the rectus muscles are separated by an abnormal distance along the linea alba, without fascial defect. 
The linea alba is composed of collagen fibres that originate from the sheath of the rectus muscles and present a complex three-dimensional organization .
Its width increases from 11 to 21 mm from the xiphoid to the umbilicus and decreases from 11 to 2 mm from the umbilicus to the pubic symphysis. The thickness of the linea alba is minimal from the xiphoid to the umbilicus, then it increases and remains more or less constant from the umbilicus to the pubis.
Although there is no consensus on the definition of RD, it is often defined in the literature as a separation of the rectus muscles greater than 22-30 mm.  
RD is characterised by a gradual thinning and widening of the linea alba, combined with a general laxity of the muscles of the ventral abdominal wall that leads to a gradual impairment of abdominal wall function  and the prolapse of the abdominal contents in the midline covered by the teguments and aponeurosis.
A non-physiological IRD (Inter Rectus Distance) creates alterations in the function of the entire abdominal wall, considered by recent studies to be a true “organ’’ .
DR can occur in both sexes, in all age groups, but is mainly observed in women after childbirth with a prevalence of 30-70% .
In women, the condition was also found in 38.7 per cent of women undergoing an abdominal hysterectomy  and in 52% of urogynecological patients undergoing menopause .
In men, on the other hand, it is associated with various risk factors such as obesity, weight fluctuations, excessive sporting activity, a familiar weakness of the abdominal muscles, old age and all the conditions that can lead to the progressive separation of the rectus muscles over time .
In pregnant women, the condition is almost constant and is functional to the increase in volume of the abdominal cavity necessary to accommodate the gravidic uterus.
The increase in intra-abdominal pressure creates an excessive stretching of the linea alba until it separates the two muscles beyond their physiological distance (< 2 cm), and this results functionally in an altered dynamic of the entire addominus muscles. 
The literature has shown that RD is present in 39-45.5% of women 6 months after delivery and in 32.6 % one year after delivery. 
It is most frequently localised at the level of the umbilicus, but can extend and include the supraumbilical or infraumbilical region .
Diastasis usually regresses spontaneously within approximately 8-12 weeks after delivery, but in 30 per cent of cases this does not occur. In this case we speak of pathological diastasis. This condition is mistakenly considered as an aesthetic condition by the vast majority of surgeons.
In our experience it is a pathology that not only involves the abdominal wall but also profoundly affects the function of the paravertebral and pelvic floor muscles, thus compromising the quality of life of patients.
The aim of the present work was to evaluate the effect of reconstruction of the linea alba with the new minimally invasive MISAR technique using a dynamo-metre as a demonstration of the improvement in abdominal wall strength at 3 and 6 months after surgery.
Secondary endpoints included improvement in quality of life (QoL), misurated by EuraHS-QoL; the improvement in the degree of severity of urinary incontinence
severity, as estimated by the Incontinence Severity Index (ISI) and pain-related disability with the Oswestry Disability Index (ODI) scale.
The present study is a prospective analysis of 19 patients with a clinical and radiological diagnosis of rectus muscle diastasis and concomitant ventral hernia who are referred to the Department of General Surgery "Pietro Valdoni" of the Policlinico Umberto I University Hospital in Rome, in the period between May 2021 and December 2021.
All patients underwent surgery according to the minimally invasive MISAR (Minimal Invasive Stapled Abdominal Reconstruction) procedure and were examined before surgery and then 3 months and 6 months after surgery.
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