A side stitch (or "stitch in one's side") is an intense stabbing abdominal pain under the lower edge of the ribcage that occurs during exercise. It is also called a side ache, side cramp, muscle stitch, or simply stitch, and the medical term is exercise-related transient abdominal pain (ETAP). [1] It sometimes extends to shoulder tip pain, and commonly occurs during running, swimming, and horseback riding. Approximately two-thirds of runners will experience at least one episode of a stitch each year. The precise cause is unclear, although it most likely involves irritation of the abdominal lining, and the condition is more likely after consuming a meal or a sugary beverage. If the pain is present only when exercising and is completely absent at rest, in an otherwise healthy person, it does not require investigation. Typical treatment strategies involve deep breathing and/or manual pressure on the affected area.
The precise cause of ETAP is unclear. Proposed mechanisms include diaphragmatic ischemia (insufficient oxygen); stress on the supportive visceral ligaments that attach the abdominal organs to the diaphragm; gastrointestinal ischemia or distension; cramping of the abdominal musculature; ischemic pain resulting from compression of the celiac artery by the median arcuate ligament under the diaphragm; aggravation of the spinal nerves; or, most likely, irritation of the parietal peritoneum (abdominal lining). [1] [2]
Although the diaphragm is mostly innervated by the phrenic nerve, and thus could explain referred pain to the shoulder tip region, the main evidence against diaphragmatic ischemia is that ETAP can be induced by activities of low respiratory demand, such as horse, camel, and motorbike riding, where ischemia of the diaphragm is unlikely. In a study using a fluoroscopic technique, diaphragmatic movements during an ETAP episode have been shown to be full and unrestricted. [2] In another study, researchers analyzed flow-volume loops from subjects who were experiencing ETAP and found no compromise in any measures of breathing, suggesting that the diaphragm is not implicated directly in the causation of ETAP. [3]
Some have proposed that this abdominal pain may be caused by internal organs (like the liver and stomach) pulling downwards on the diaphragm, [4] but this hypothesis is inconsistent with its frequent occurrence during swimming, [1] which involves almost no downward force on these organs.
Frictional irritation of the parietal peritoneum has been suggested as a cause of ETAP. [1] The parietal peritoneum is the outer layer of the peritoneum that adheres to the abdominal wall and underside of the diaphragm. Because the portion of the peritoneum that underlies the diaphragm is innervated by the phrenic nerve, it could explain the shoulder tip pain. [5] [6] [7] The parietal peritoneum traverses the entire abdominal wall, which could account for the widespread distribution of ETAP; the tension in the parietal peritoneum is increased with torso extension; children have a proportionally larger peritoneal surface compared to adults, which could explain the increased prevalence of ETAP in younger individuals; [2] [8] and pain arising from the parietal peritoneum relieves quickly on removal of the stimulus, [5] similar to what is observed for ETAP when activity is ceased. [3] After a meal, distention of the stomach could increase friction between the visceral and parietal layers of peritoneum, [1] and sugary beverages could provoke ETAP due to slower emptying of the stomach. [9] In fact, the fluid in the peritoneal cavity is highly responsive to osmotic gradients between it and its vascular supply. [2]
In the absence of a clear cause, any treatment techniques are uncertain. Typical strategies involve deep breathing and/or manual pressure on the affected area. [2]
Side stitches occur in every level of athletes from school-aged children, weekend exercisers, or elite athletes, although they are more common in younger people. Activities that use upper body twists, like running, swimming, and horseback riding, report this affliction more often. Approximately two-thirds of runners will experience at least one episode of a stitch each year. [10]
The peritoneum is the serous membrane forming the lining of the abdominal cavity or coelom in amniotes and some invertebrates, such as annelids. It covers most of the intra-abdominal organs, and is composed of a layer of mesothelium supported by a thin layer of connective tissue. This peritoneal lining of the cavity supports many of the abdominal organs and serves as a conduit for their blood vessels, lymphatic vessels, and nerves.
Laparoscopy is an operation performed in the abdomen or pelvis using small incisions with the aid of a camera. The laparoscope aids diagnosis or therapeutic interventions with a few small cuts in the abdomen.
Peritonitis is inflammation of the localized or generalized peritoneum, the lining of the inner wall of the abdomen and cover of the abdominal organs. Symptoms may include severe pain, swelling of the abdomen, fever, or weight loss. One part or the entire abdomen may be tender. Complications may include shock and acute respiratory distress syndrome.
The pleural cavity, pleural space, or interpleural space is the potential space between the pleurae of the pleural sac that surrounds each lung. A small amount of serous pleural fluid is maintained in the pleural cavity to enable lubrication between the membranes, and also to create a pressure gradient.
The phrenic nerve is a mixed motor/sensory nerve that originates from the C3-C5 spinal nerves in the neck. The nerve is important for breathing because it provides exclusive motor control of the diaphragm, the primary muscle of respiration. In humans, the right and left phrenic nerves are primarily supplied by the C4 spinal nerve, but there is also a contribution from the C3 and C5 spinal nerves. From its origin in the neck, the nerve travels downward into the chest to pass between the heart and lungs towards the diaphragm.
The thoracic diaphragm, or simply the diaphragm, is a sheet of internal skeletal muscle in humans and other mammals that extends across the bottom of the thoracic cavity. The diaphragm is the most important muscle of respiration, and separates the thoracic cavity, containing the heart and lungs, from the abdominal cavity: as the diaphragm contracts, the volume of the thoracic cavity increases, creating a negative pressure there, which draws air into the lungs. Its high oxygen consumption is noted by the many mitochondria and capillaries present; more than in any other skeletal muscle.
The mesentery is an organ that attaches the intestines to the posterior abdominal wall and is formed by the double fold of peritoneum. It helps in storing fat and allowing blood vessels, lymphatics, and nerves to supply the intestines, among other functions.
The peritoneal cavity is a potential space between the parietal peritoneum and visceral peritoneum. The parietal and visceral peritonea are layers of the peritoneum named depending on their function/location. It is one of the spaces derived from the coelomic cavity of the embryo, the others being the pleural cavities around the lungs and the pericardial cavity around the heart.
Kehr's sign is the occurrence of acute pain in the tip of the shoulder due to the presence of blood or other irritants in the peritoneal cavity when a person is lying down and the legs are elevated. Kehr's sign in the left shoulder is considered a classic symptom of a ruptured spleen. May result from diaphragmatic or peridiaphragmatic lesions, renal calculi, splenic injury or ruptured ectopic pregnancy.
An abdominal pregnancy is a rare type of ectopic pregnancy where the embryo or fetus is growing and developing outside the uterus, in the abdomen, and not in a fallopian tube, an ovary, or the broad ligament.
Pneumoperitoneum is pneumatosis in the peritoneal cavity, a potential space within the abdominal cavity. The most common cause is a perforated abdominal organ, generally from a perforated peptic ulcer, although any part of the bowel may perforate from a benign ulcer, tumor or abdominal trauma. A perforated appendix seldom causes a pneumoperitoneum.
Catamenial pneumothorax is a spontaneous pneumothorax that recurs during menstruation, within 72 hours before or after the onset of a cycle. It usually involves the right side of the chest and right lung, and is associated with thoracic endometriosis. A third to a half of patients have pelvic endometriosis as well. Despite this association, CP is still considered to be misunderstood as is endometriosis considered to be underdiagnosed. The lack of a clear cause means that diagnosis and treatment is difficult. The disease is believed to be largely undiagnosed or misdiagnosed, leaving the true frequency unknown in the general population.
The bare area of the liver is a large triangular area on the diaphragmatic surface of the liver. It is the only part of the liver with no peritoneal covering, although it is still covered by Glisson’s capsule. It is attached directly to the diaphragm by loose connective tissue. The bare area of the liver is relevant to the portacaval anastomosis, encloses the right extraperitoneal subphrenic space, and can be a site of spread of infection from the abdominal cavity to the thoracic cavity
Diaphragmatic rupture is a tear of the diaphragm, the muscle across the bottom of the ribcage that plays a crucial role in breathing. Most commonly, acquired diaphragmatic tears result from physical trauma. Diaphragmatic rupture can result from blunt or penetrating trauma and occurs in about 0.5% of all people with trauma.
Peritoneal mesothelioma is the name given to the cancer that attacks the lining of the abdomen. This type of cancer affects the lining that protects the contents of the abdomen and which also provides a lubricating fluid to enable the organs to move and work properly.
The Wittmann Patch is a temporary abdominal fascia prosthesis for the planned open abdomen to ease the management of cases where the abdomen cannot be closed due to abdominal compartment syndrome or because multiple further operations are planned. It consists of a sterile hook and a sterile loop sheet made from propylene and nylon.
Surgical humidification is the conditioning of insufflation gas with water vapour (humidity) and heat during surgery. Surgical humidification is used to reduce the risk of tissue drying and evaporative cooling.
The development of the digestive system in the human embryo concerns the epithelium of the digestive system and the parenchyma of its derivatives, which originate from the endoderm. Connective tissue, muscular components, and peritoneal components originate in the mesoderm. Different regions of the gut tube such as the esophagus, stomach, duodenum, etc. are specified by a retinoic acid gradient that causes transcription factors unique to each region to be expressed. Differentiation of the gut and its derivatives depends upon reciprocal interactions between the gut endoderm and its surrounding mesoderm. Hox genes in the mesoderm are induced by a Hedgehog signaling pathway secreted by gut endoderm and regulate the craniocaudal organization of the gut and its derivatives. The gut system extends from the oropharyngeal membrane to the cloacal membrane and is divided into the foregut, midgut, and hindgut.
The pulmonary pleurae are the two opposing layers of serous membrane overlying the lungs and the inside of the surrounding chest walls.
Running injuries affect about half of runners annually. The frequencies of various RRI depend on the type of running, such as speed and mileage. Some injuries are acute, caused by sudden overstress, such as side stitch, strains, and sprains. Many of the common injuries that affect runners are chronic, developing over longer periods as the result of overuse. Common overuse injuries include shin splints, stress fractures, Achilles tendinitis, Iliotibial band syndrome, Patellofemoral pain, and plantar fasciitis.