Rectus Sheath

Acquired Abnormalities Rectus Abdominis Diastasis Rectus abdominis diastasis (or diastasis recti) describes a clinically evident separation of the rectus abdominus muscle pillars, generally as a result of decreased tone of the abdominal musculature. The characteristic bulging of the abdominal wall in the epigastrium is sometimes mistaken for a ventral hernia, despite the fact that the .midline aponeurosis is intact and no hernia defect is present Diastasis may be congenital, as a result of a more lateral insertion of the rectus muscles to the ribs and costochondral junctions, but is more typically an acquired condition with advancing age, obesity, or following pregnancy. In the postpartum setting, rectus diastasis tends to occur in women of 1- advanced maternal age,2- after multiple or twin pregnancies, or 3-in women who deliver high-birth-weight infants. Diastasis is usually easily identified on physical examination (Fig. 34-6). Computed tomography (CT) scanning provides an accurate means of measuring the distance between the rectus pillars and will differentiate rectus diastasis from a true ventral hernia if clarification is required. Surgical correction of a severe rectus diastasis by plication of the anterior rectus sheath may be undertaken for cosmetic indications, or .if it is associated with disability of abdominal wall muscular function

Rectus Sheath Hematoma The terminal branches of the superior and inferior epigastric arteries course deep to the posterior aspect of the left and right rectus pillars and penetrate the posterior rectus sheath. Injury to these vessels or to any of the network of collateralizing vessels .within the rectus sheath and muscles can result in a rectus sheath hematoma Although there may be a history of significant blunt trauma, less-obvious events also have been reported to cause this condition, such as sudden contraction of the rectus muscles with coughing, sneezing, or any-1 .vigorous physical activity Spontaneous rectus sheath hematomas have been described in the elderly and in-2 .those on anticoagulation therapy Patients frequently describe the sudden onset of unilateral abdominal pain that may be confused with lateralized peritoneal disorders such as appendicitis. Below the arcuate line, a hematoma may cross the midline and cause bilateral .lower quadrant pain History and physical examination alone may be diagnostic. Pain typically increases with contraction of the rectus muscles and a tender mass may be palpated. The ability to appreciate an intra-abdominal mass is ordinarily degraded with contraction of the rectus muscles. Fothergill's sign is a palpable abdominal mass that remains unchanged with contraction of the rectus muscles and is classically associated with rectus hematoma. A hemoglobin/hematocrit level and coagulation studies should be obtained. Abdominal ultrasonography may show a solid or cystic mass within the abdominal wall, depending on the chronicity of the bleeding event. Computed tomography is the most definitive study for establishing the correct diagnosis and excluding other intra-abdominal disorders. Magnetic resonance imaging (MRI) also .has been employed for this purpose

Specific treatment depends on the severity of the hemorrhage. Small, unilateral, and contained hematomas may be observed without hospitalization. Bilateral or large hematomas will likely require hospitalization, as well as potential resuscitation. The need for a red blood cell or coagulation factor transfusion is determined by the clinical circumstances. Reversal of warfarin (Coumadin) anticoagulation in the acute setting is frequently, but not always, necessary. Emergent operative intervention or angiographic embolization is required infrequently, but may be necessary if hematoma enlargement, free bleeding, or clinical deterioration occur. Surgical therapy consists of evacuation of the hematoma and ligation of any bleeding vessel identified. Mortality in this condition is rare, but has been reported in patients requiring surgical treatment and in the elderly