The hallmark of the condition is a sunken appearance of the sternum. The most common form is a cup-shaped concavity, involving the lower end of the sternum; also a broader concavity involving the upper costal cartilages is possible. The lower-most ribs may protrude ("flared ribs"). Pectus excavatum defects may be symmetric or asymmetric.

People may also experience chest and back pain, which is usually of musculoskeletal origin.

In mild cases, cardiorespiratory function is normal, although the heart can be displaced and/or rotated. In severe cases, mitral valve prolapse may be present and physical capability may be limited due to base lung capacity being decreased.

Psychological symptoms manifest with feelings of embarrassment, social anxiety, shame, limited capacity for activities and communication, negativity, intolerance, frustration, and even depression.

Pectus excavatum is a congenital deformity of the anterior thoracic wall in which the sternum and rib cage grow abnormally. This produces a caved-in or sunken appearance of the chest. It can either be present at birth or not develop until puberty.

Pectus excavatum is sometimes considered to be cosmetic, but depending on the severity, it can impair cardiac and respiratory function and cause pain in the chest and back.

People with the condition may experience negative psychosocial effects, and avoid activities that expose the chest in some societies.

An external pancreatic fistula is an abnormal communication between the pancreas (actually pancreatic duct) and the exterior of the body via the abdominal wall.

Loss of bicarbonate-rich pancreatic fluid via a pancreatic fistula can result in a hyperchloraemic or normal anion gap metabolic acidosis. Loss of a small volume of fluid will not cause a problem but an acidosis is common if the volume of pancreatic fluid lost from the body is large.

A pancreatic fistula is an abnormal communication between the pancreas and other organs due to leakage of pancreatic secretions from damaged pancreatic ducts. An "external" pancreatic fistula is one that communicates with the skin, and is also known as a pancreaticocutaneous fistula, whereas an internal pancreatic fistula communicates with other internal organs or spaces. Pancreatic fistulas can be caused by pancreatic disease, trauma, or surgery.

Patients with MALS reportedly experience abdominal pain, particularly in the epigastrium, which may be associated with eating and which may result in anorexia and weight loss.The pain can be in the left or right side, but usually where the ribs meet. Other signs are persistent nausea, lassitude (especially after a heavy meal) and exercise intolerance. Diarrhea is a common symptom, some experience constipation. While some experience vomiting, not everyone does. Exercise or certain postures can aggravate the symptoms. Occasionally, physical examination reveals an abdominal bruit in the mid-epigastrium.

Complications of MALS result from chronic compression of the celiac artery. They include gastroparesis and aneurysm of the pancreaticoduodenal arteries.

Pelvic floor dysfunction refers to a wide range of issues that occur when muscles of the pelvic floor are weak, tight, or there is an impairment of the sacroiliac joint, lower back, coccyx, or hip joints. Symptoms include pelvic pain, pressure, pain during sex, incontinence, incomplete emptying, and visible organ protrusion. Tissues surrounding the pelvic organs may have increased or decreased sensitivity or irritation resulting in pelvic pain. Many times, the underlying cause of pelvic pain is difficult to determine. The condition affects up to 50% of women.

Pelvic floor dysfunction may include any of a group of clinical conditions that includes urinary incontinence, fecal incontinence, pelvic organ prolapse, sensory and emptying abnormalities of the lower urinary tract, defecatory dysfunction, sexual dysfunction and several chronic pain syndromes, including vulvodynia. The three most common and definable conditions encountered clinically are urinary incontinence, anal incontinence and pelvic organ prolapse.

Splenic flexure syndrome is a term sometimes used to describe bloating, muscle spasms of the colon, and upper abdominal discomfort thought to be caused by trapped gas at the splenic (as opposed to hepatic) flexure in the colon; the pain caused can be excruciating and debilitating, and may mimic that of a heart attack (because of the proximity of the splenic flexure to the diaphragm and referred pain from irritation to the diaphragmatic sensory nerves).

Some physicians classify splenic flexure syndrome as a type of IBS; others consider it a separate condition.

It is estimated that in 10-24% of normal, asymptomatic individuals the median arcuate ligament crosses in front of (anterior to) the celiac artery, causing some degree of compression. Approximately 1% of these individuals exhibit severe compression associated with symptoms of MALS. The syndrome most commonly affects individuals between 20 and 40 years old, and is more common in women, particularly thin women.

Additional symptoms include:

- anencephaly (failure of major sections of the brain to form)

- encephalocele (cranial contents protrudes from the skull)

- cyclopia (the two eye cavities fuse into one)

- agnathia

- cleft palate

- arthrogryposis

- clubfeet

- holoprosencephaly

- spina bifida

- low-set ears

- pulmonary hypoplasia

- omphalocele

- gastroschisis

- cardiovascular disorders

- diaphragmatic hernias

- gastrointestinal atresia

- single umbilical artery

- renal abnormalities

- genu recurvatum

- hydramnios

Rupture of the urethra is an uncommon result of penile injury, incorrect catheter insertion, straddle injury, or pelvic girdle fracture. The urethra, the muscular tube that allows for urination, may be damaged by trauma. When urethral rupture occurs, urine may extravasate (escape) into the surrounding tissues. The membranous urethra is most likely to be injured in pelvic fractures, allowing urine and blood to enter the deep perineal space and subperitoneal spaces via the genital hiatus. The spongy urethra is most likely to be injured with a catheter or in a straddle injury, allowing urine and blood to escape into the scrotum, the penis, and the superficial peritoneal space. Urethral rupture may be diagnosed with a cystourethrogram. Due to the tight adherence of the fascia lata, urine from a urethral rupture cannot spread into the thighs.

The affected infant tends to be short, with a disproportionately large head. The fetal head of Infants born with iniencephaly are hyperextended while the foramen magnum is enlarged and opens through the widened pedicles. The defective neural arches directly into the upper cervical reach of the spinal canal, causing the formation of a common cavity between most of the spinal cord and the brain. The skin of the anterior chest is connected directly to the face, bypassing the formation of a neck, while the scalp is directly connected to the skin of the back. Because of this, those born with this anomaly either have a highly shortened neck or no neck at all. This causes extreme retroflexion, or backward bending, of the head in a "star-gazing" fashion. The spine is severely distorted as well along with significant shortening due to marked lordosis. The vertebrae, especially cervical, are fused together in abnormal shapes and their numbers are reduced. The spinal cord is almost always defective while the ventricular system is often dilated and the cortex is thinned. Sometimes, in the case of iniencephaly apertus, an encephalocele (sac-like protrusions of the brain through an opening in the cranium) forms.

Mechanistically, the causes of pelvic floor dysfunction are two-fold: widening of the pelvic floor hiatus and descent of pelvic floor below the pubococcygeal line, with specific organ prolapse graded relative to the hiatus. Associations include obesity, menopause, pregnancy and childbirth. Some women may be more likely to developing pelvic floor dysfunction because of an inherited deficiency in their collagen type. Some women may have congenitally weak connective tissue and fascia and are therefore at risk of stress urinary incontinence and pelvic organ prolapse.

By definition, "postpartum" pelvic floor dysfunction only affects women who have given birth, though pregnancy rather than birth or birth method is thought to be the cause. A study of 184 first-time mothers who delivered by Caesarean section and 100 who delivered vaginally found that there was no significant difference in the prevalence of symptoms 10 months following delivery, suggesting that pregnancy is the cause of incontinence for many women irrespective of their mode of delivery. The study also suggested that the changes which occur to the properties of collagen and other connective tissues during pregnancy may affect pelvic floor function.

Pelvic floor dysfunction can result after treatment for gynegological cancers.

Prominent symptoms usually do not appear until the cancer has infiltrated over 60% of the circumference of the esophageal tube, by which time the tumor is already in an advanced stage. Onset of symptoms is usually caused by narrowing of the tube due to the physical presence of the tumor.

The first and the most common symptom is usually difficulty in swallowing, which is often experienced first with solid foods and later with softer foods and liquids. Pain when swallowing is less usual at first. Weight loss is often an initial symptom in cases of squamous-cell carcinoma, though not usually in cases of adenocarcinoma. Eventual weight loss due to reduced appetite and undernutrition is common. Pain behind the breastbone or in the region around the stomach often feels like heartburn. The pain can frequently be severe, worsening when food of any sort is swallowed. Another sign may be an unusually husky, raspy, or hoarse-sounding cough, a result of the tumor affecting the recurrent laryngeal nerve.

The presence of the tumor may disrupt the normal contractions of the esophagus when swallowing. This can lead to nausea and vomiting, regurgitation of food and coughing. There is also an increased risk of aspiration pneumonia due to food entering the airways through the abnormal connections (fistulas) that may develop between the esophagus and the trachea (windpipe). Early signs of this serious complication may be coughing on drinking or eating. The tumor surface may be fragile and bleed, causing vomiting of blood. Compression of local structures occurs in advanced disease, leading to such problems as upper airway obstruction and superior vena cava syndrome. Hypercalcemia (excess calcium in the blood) may occur.

If the cancer has spread elsewhere, symptoms related to metastatic disease may appear. Common sites of spread include nearby lymph nodes, the liver, lungs and bone. Liver metastasis can cause jaundice and abdominal swelling (ascites). Lung metastasis can cause, among other symptoms, impaired breathing due to excess fluid around the lungs (pleural effusion), and dyspnea (the feelings often associated with impaired breathing).

Rumination syndrome in adults is a complicated disorder whose symptoms can mimic those of several other gastroesophogeal disorders and diseases. Bulimia nervosa and gastroparesis are especially prevalent among the misdiagnoses of rumination.

Bulimia nervosa, among adults and especially adolescents, is by far the most common misdiagnosis patients will hear during their experiences with rumination syndrome. This is due to the similarities in symptoms to an outside observer—"vomiting" following food intake—which, in long-term patients, may include ingesting copious amounts to offset malnutrition, and a lack of willingness to expose their condition and its symptoms. While it has been suggested that there is a connection between rumination and bulimia, unlike bulimia, rumination is not self-inflicted. Adults and adolescents with rumination syndrome are generally well aware of their gradually increasing malnutrition, but are unable to control the reflex. In contrast, those with bulimia intentionally induce vomiting, and seldom re-swallow food.

Gastroparesis is another common misdiagnosis. Like rumination syndrome, patients with gastroparesis often bring up food following the ingestion of a meal. Unlike rumination, gastroparesis causes vomiting (in contrast to regurgitation) of food, which is not being digested further, from the stomach. This vomiting occurs several hours after a meal is ingested, preceded by nausea and retching, and has the bitter or sour taste typical of vomit.

While the number and severity of symptoms varies among individuals, repetitive regurgitation of undigested food (known as rumination) after the start of a meal is always present. In some individuals, the regurgitation is small, occurring over a long period of time following ingestion, and can be rechewed and swallowed. In others, the amount can be bilious and short lasting, and must be expelled.

While some only experience symptoms following some meals, most experience episodes following any ingestion, from a single bite to a massive feast. However, some long-term patients will find a select couple of food or drink items that do not trigger a response.

Unlike typical vomiting, the regurgitation is typically described as effortless and unforced. There is seldom nausea preceding the expulsion, and the undigested food lacks the bitter taste and odour of stomach acid and bile.

Symptoms can begin to manifest at any point from the ingestion of the meal to 120 minutes thereafter. However, the more common range is between 30 seconds to 1 hour after the completion of a meal. Symptoms tend to cease when the ruminated contents become acidic.

Abdominal pain (38.1%), lack of fecal production or constipation (21.1%), nausea (17.0%), diarrhea (8.2%), bloating (4.1%), and dental decay (3.4%) are also described as common symptoms in day-to-day life. These symptoms are not necessarily prevalent during regurgitation episodes, and can happen at any time. Weight loss is often observed (42.2%) at an average loss of 9.6 kilograms, and is more common in cases where the disorder has gone undiagnosed for a longer period of time, though this may be expected of the nutrition deficiencies that often accompany the disorder as a consequence of its symptoms. Depression has also been linked with rumination syndrome, though its effects on rumination syndrome are unknown.

Acid erosion of the teeth can be a feature of rumination, as can halitosis (bad breath).

Accessory spleens may be formed during embryonic development when some of the cells from the developing spleen are deposited along the path from the midline, where the spleen forms, over to its final location on the left side of the abdomen by the 9th–11th ribs. The most common locations for accessory spleens are the hilum of the spleen and adjacent to the tail of the pancreas. They may be found anywhere along the splenic vessels, in the gastrosplenic ligament, the splenorenal ligament, the walls of the stomach or intestines, the pancreatic tail, the greater omentum, the mesentery or the gonads and their path of descent. The typical size is approximately 1 centimeter, but sizes ranging from a few millimeters up to 2–3 centimeters are not uncommon.

Splenogonadal fusion can result in one or more accessory spleens along a path from the abdomen into the pelvis or scrotum. The developing spleen forms near the urogenital ridge from which the gonads develop. The gonads may pick up some tissue from the spleen, and as they descend through the abdomen during development, they can produce either a continuous or a broken line of deposited splenic tissue.

Splenosis is a condition where foci of splenic tissue undergo autotransplantation, most often following physical trauma or splenectomy. Displaced tissue fragments can implant on well vascularized surfaces in the abdominal cavity, or, if the diaphragmatic barrier is broken, the thorax.

An accessory spleen ("supernumerary spleen", "splenule", or "splenunculus") is a small nodule of splenic tissue found apart from the main body of the spleen. Accessory spleens are found in approximately 10 percent of the population and are typically around 1 centimeter in diameter. They may resemble a lymph node or a small spleen. They form either by the result of developmental anomalies or trauma. They are medically significant in that they may result in interpretation errors in diagnostic imaging or continued symptoms after therapeutic splenectomy.

The most obvious sign that meconium has been passed during or before labor is the greenish or yellowish appearance of the amniotic fluid. The infant's skin, umbilical cord, or nailbeds may be stained green if the meconium was passed a considerable amount of time before birth. These symptoms alone do not necessarily indicate that the baby has inhaled in the fluid by gasping in utero or after birth. After birth, rapid or labored breathing, cyanosis, slow heartbeat, a barrel-shaped chest or low Apgar score are all signs of the syndrome. Inhalation can be confirmed by one or more tests such as using a stethoscope to listen for abnormal lung sounds (diffuse 'wet' crackles and rhonchi), performing blood gas tests to confirm a severe loss of lung function (respiratory acidosis as a consequence of hypercapnia), and using chest X-rays to look for patchy or streaked areas on the lungs. Infants who have inhaled meconium may develop respiratory distress syndrome often requiring ventilatory support. Complications of MAS include pneumothorax and persistent pulmonary hypertension of the newborn.

Esophageal cancers are typically carcinomas that arise from the epithelium, or surface lining, of the esophagus. Most esophageal cancers fall into one of two classes: esophageal squamous-cell carcinomas (ESCC), which are similar to head and neck cancer in their appearance and association with tobacco and alcohol consumption—and esophageal adenocarcinomas (EAC), which are often associated with a history of GERD and Barrett's esophagus. A rule of thumb is that a cancer in the upper two-thirds is likely to be ESCC and one in the lower one-third EAC.

Rare histologic types of esophageal cancer include different variants of squamous-cell carcinoma, and non-epithelial tumors, such as leiomyosarcoma, malignant melanoma, rhabdomyosarcoma and lymphoma, among others.

Meconium aspiration syndrome (MAS) also known as neonatal aspiration of meconium is a medical condition affecting newborn infants. It occurs when meconium is present in their lungs during or before delivery. Meconium is the first stool of an infant, composed of materials ingested during the time the infant spends in the uterus.

Meconium is normally stored in the infant's intestines until after birth, but sometimes (often in response to fetal distress and hypoxia) it is expelled into the amniotic fluid prior to birth, or during labor. If the baby then inhales the contaminated fluid, respiratory problems may occur.

The primary malformation apparent with JBS is hypoplasia (underdevelopment) of the nasal alae, or "wing of the nose". Both hypoplasia and aplasia (partial or complete absence) of structural cartilage and tissue in this area of the nose, along with the underlying alae nasi muscle, are prevailing features of the disorder. Together, these malformations give the nose and nostrils an odd shape and appearance.

The most prominent effect of JBS is pancreatic exocrine insufficiency. Varying degrees of decreased secretion of lipases, pancreatic juices such as trypsin, trypsinogen and others, as well as malabsorption of fats and disruptions of glucagon secretion and its response to hypoglycemia caused by insulin activity are major concerns when JBS is diagnosed. Associated with developmental errors, impaired apoptosis, and both prenatal and chronic inflammatory damage, necrosis and fibrosis of the pancreatic acini (clusters of pancreatic exocrine gland tissue, where secretion of pancreatic juice and related enzymes occurs), pancreatic exocrine insufficiency in JBS can additionally stem from congenital replacement of the acini with fatty tissue. Near total replacement of the entire pancreas with fatty tissue has also been reported. This is a progressive, sometimes fatal consequence of the disorder.

The onset of myelomalacia may be so subtle that it is overlooked. Depending on the extent of the spinal cord injury, the symptoms may vary. In some cases, the symptom may be as common as hypertension. Though every case is different, several cases reported loss of motor functions in the extremities, areflexia or sudden jerks of the limbs, loss of pain perception, or even paralysis; all of which are possible indicators of a damaged and softened spinal cord. In the most severe cases, paralysis of the respiratory system manifests in death.

Symptoms may include abdominal pain or vaginal bleeding during pregnancy. As this is nonspecific in areas where ultrasound is not available the diagnosis was often only discovered during surgery to investigate the abnormal symptoms. They are typically diagnosed later in the developing world than the developed. In about half of cases from a center in the developing world the diagnosis was initially missed.

It is a dangerous condition as there can be bleeding into the abdomen that results in low blood pressure and can be fatal. Other causes of death in people with an abdominal pregnancy include anemia, pulmonary embolus, coagulopathy, and infection.

An abdominal pregnancy can be regarded as a form of an ectopic pregnancy where the embryo or fetus is growing and developing outside the womb in the abdomen, but not in the Fallopian tube, ovary or broad ligament.

While rare, abdominal pregnancies have a higher chance of maternal mortality, perinatal mortality and morbidity compared to normal and ectopic pregnancies; on occasion, however, a healthy viable infant can be delivered.

Because tubal, ovarian and broad ligament pregnancies are as difficult to diagnose and treat as abdominal pregnancies, their exclusion from the most common definition of abdominal pregnancy has been debated.

Others—in the minority—are of the view that abdominal pregnancy should be defined by a placenta implanted into the peritoneum.