Rectus Abdominis

The Rectus Abdominis is a muscle of the abdomen.

The abdominal muscles are frequently referred to as the Abs.

Anatomical Attachments:

•   Origin: Attaches to the pubic symphysis and the medial crest of the pubis.
•   Insertion: Attaches to the xiphoid process and the costal cartilages of the 5th, 6th and 7th ribs.

Action: It compresses the abdomen, flexes the pelvis and the vertebral column, and supports and protects the abdominal viscera.

Synergist:  Psoas major, Psoas minor, Diaphragm, Internal oblique abdominis, Transverse abdominis, Pyramidalis, Levator Ani.

Antagonist: Interspinales, Multifidus, Intertransversarii.

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Nerve Supply: Thoracic nerves (T6, T7, T8, T9, T10, T11, and T12).

Nerve Entrapment: According to Travell and Simons, the Rectus abdominis can entrap either within the muscle or its sheath of one or more anterior branches of the spinal nerves, given rise to abdominal, pelvic or gynecological complaints. They additionally reference, trigger point injections of procaine as an excellent means of deactivating triggers and being able to differentiate between myofascial pain, entrapment, and visceral disease.

Vascular supply: Superior and inferior epigastric arteries.

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Trigger Point Signs and Symptoms: Rectus Abdominis syndrome - Bilateral pain across the upper thoracic region, precordial pain, nausea and vomiting, abdominal cramping, colic, bloating, swelling and gas, bilateral low back pain, intensified dysmenorrhea. Author’s Note: The condition, known as Rectus Abdominis Syndrome, should not be confused with a Weakened Rectus Abdominis Syndrome or a Pseudo GI Syndrome. With a Weakened Rectus Abdominis Syndrome and a Pseudo GI Syndrome you may observe abdominal distention and excessive flatus. With a Weakened Rectus abdominis, the condition is persistent and usually the result of, either a sedimentary lifestyle or the side effect of a previous abdominal surgery and/or pregnancy. With a Pseudo GI Syndrome, the abdominal distention, flatus, nausea and vomiting, maybe episodic and frequently is confused with visceral disease; when the true etiology is a mid thoracic nerve compression. Usually the individual is aware of at least minor mid-back discomfort prior to the gastrointestinal symptomatology ensuing; and frequently they have a history of hyperextension of the thoracic spine. To establish a possible mid thoracic nerve compression or inflammation, the physician/practitioner can inject an anti-inflammatory medication such as Depo-Medrol into the paraspinals surrounding the suspected segment. If the condition is a Pseudo GI syndrome, the symptoms will ameliorate within 20 minutes; unless, the pain is caused by trigger points or is visceral in nature, at which time, there will be no change in symptomatology. Dr. Travell and Simons recommend the injection into trigger points, of a local anesthesia such as Procaine, to deactivate triggers within this muscle which can mimic visceral pain. We recommend the utilization of the anti-inflammatory prior to the application of the local anesthetic, should the practitioner be confused as to which is the cause or the effect of referral pain. Obviously, most somatic practitioners will employ manual care for the treatment of either nerve compression or triggers, but should the somatic pain persist following manual care, this technique may be employed by a physician to not only treat, but establish causation.

Trigger Point Activating and Perpetuating Factors: Abdominal scars from surgery, acute trauma, chronic occupational strain, over exercise, emotional tension, viral infections, straining during fecal elimination, poor posture.

Differential Diagnosis: Articular dysfunction of the thoracic or lumbar region, Fibromyalgia, Appendicitis, Peptic ulcer (Stomach ulcer), Stomach perforation, Gastric carcinoma (Stomach cancer), Ascites, Polyps, Rectus abdominis hematoma, Chronic Cholecystitis or Ureteral colic, Gallbladder Disorder, Colic, Constipation, Intestinal Obstruction (Fecal impaction, Hernia, Adhesions), Painful rib syndrome, Urinary tract disease, Hiatal hernia, Inguinal hernia, Hepatitis, Pancreatitis, Pancreatic carcinoma, Diverticulosis, Umbilical hernia, Degenerative disc disease, (Segmental, Subluxation, Somatic dysfunction) T2 T3 or T4 radiculopathy, L1 L2 or L4 radiculopathy, Intervertebral stenosis, Costochondritis, Ascariasis, Epilepsy, Myocardial infarction, Angina pectoris, Aortic Aneurysm, Iliac aneurysm, Colicystitis, Splenomegaly, Splenic flexure syndrome, Ruptured spleen, Ovarian cyst, Ovarian cancer, Pregnancy, Tubal pregnancy (Ectopic pregnancy), Spontaneous Abortion (Miscarriage), Endometriosis, Intractable dysmenorrhea, Enigmatic pelvic pain, Chronic pelvic pain, Systemic infections or inflammation, Nutritional inadequacy, Metabolic imbalance, Toxicity, Side effects of medication.
 

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