Pain – Pelvic Pain

Introduction

Learning Objectives

    • Upon completion of this tutorial the learner should be able to:
    • Discuss the causes of the pelvic pain
    • Describe the applied anatomy of the pelvis
    • Discuss the physiology and pathophysiology
    • Explain the characteristic clinical presentations of pelvic pain.
    • Recognize the usual diagnostic algorithm and procedures that are performed.
    • Explain the general approach to the management

Introduction

Pelvic pain is an uncomfortable painful sensation felt in the pelvis.  Pelvic pain is a common gynecological complaint and can be broadly classified as cyclic, acute, or chronic.   There are many causes for pelvic pain, with results that range from spontaneous resolution to some such as ruptured ectopic pregnancy that can be life-threatening.  The diagnosis is often suspected clinically and imaging with ultrasound is the most commonly used modality in gynecological considerations.  Treatment ranges from medical, where pain control is the aim, to surgical, where mechanical disorders such as obstructions and ruptures are the etiology.

Non traumatic adult female pelvic pain is an extremely common entity, but it is difficult to ascertain an exact prevalence as it is felt that many women who experience pelvic pain do not seek medical care.  One estimate of chronic pelvic pain ranged between 4-25% of all women of child rearing ages.

Classification

Female pelvic pain can be divided into acute, chronic, and cyclical depending on the character and timing of the pain.   Cyclic pain is associated with menses and occurs either during the menses or the middle of the cycle when ovulation takes place.  Acute pelvic pain is intense, characterized by sudden onset, sharp character, and relatively short course. It is often accompanied by nausea, vomiting, diaphoresis, fever or leukocytosis. Chronic pelvic pain persists for greater than 3-4 months and is typically less intense in severity (although not always).

Structural Principles

The pelvis is a highly vascularized area comprised mostly of the reproductive organs and a multitude of lumbar and sacral nerve plexi. Due to its anatomical proximity to the abdominal viscera, pelvic pain may often reflect an abdominal process.

The reproductive organs, the uterus, Fallopian tubes, and ovaries, share the same nerves as lower gastrointestinal organs, including the sigmoid colon and rectum (spinal cord segments T10 through L1).  This can sometimes make it difficult to differentiate pain originating from the gastrointestinal (GI) tract versus that from the reproductive tract.

Pelvic Cavity

The pelvic cavity is the space formed by a diaphragm of pelvic muscle below and an open roof above where the distinction between the pelvic cavity and abdominal cavity is vague but best defined by the region of the bony pelvis, including the iliac crests and lumbosacral joint and sacral promontory and the pubic symphysis.  It houses the uterus, ovaries and Fallopian tubes, the bladder and distal ureters, prostate vasa deferentia, sigmoid colon and rectum.  Components of the cardiovascular system, nervous system, endocrine system, reticuloendothelial system, and musculoskeletal system are present to enable the pelvic cavity to connect with all the other parts of the body.

Similar to the cranial cavity and the thoracic cavity, there is prominent bony protection by the pelvic bones.

The Normal Pelvis
The bony pelvis is shown in the above CT scan reconstruction.  While the iliac crests and ischia and pubic symphysis are well shown, the sacral component is hidden by parts of the gastrointestinal tract.
Courtesy of: Ashley Davidoff, M.D.

Pelvic Cavity: Space Occupation

Most of the pelvic cavity is part of the peritoneal cavity but the retroperitoneum does extend down into the pelvic cavity and there is also a space called the extraperitoneal space.

Diseases and fluid accumulation can occupy space in the pelvis in the same way as they may in the abdominal cavity.  Similarly, the space occupation is not usually immediately and emergently life-threatening.  The cul de sac is a space that in the female lies between the rectum and uterus and in the male lies between the bladder and the rectum.  It is the most posterior space in the abdominal-pelvic cavity and therefore by default, is the first space to accumulate fluid when the patient is imaged in the supine projection.

Space occupation is sometimes (though rarely) a welcoming event.  In the case of the pelvis, the gravid uterus occupies space in the pelvis and although progressively uncomfortable, the final result is not only desirable but also restores the space to its usual owners.

Pregnancy – Physiological and Temporary Space Occupation
The MRI shows a fetus with vertex (head) presentation lying within the gestational sac filled with fluid (white), taking up the space of the pelvic cavity and to some extent the abdominal cavity and displacing normal structures into the abdomen.
Courtesy of: Ashley Davidoff, M.D.

When referring to pelvic pain, it is usual to assign this condition to females since pelvic pain is common as a normal physiological event for so many females.  We will focus on the female system primarily.

Female Reproductive Organs

The female organs of reproduction include the uterus, Fallopian tubes, ovaries, and vagina.  Three of the four organs are hollow.  The Fallopian tubes, vagina and uterus follow tubular principles, while the ovaries are considered solid organs.  The tubular systems all have an inner mucosal lining, a wall containing muscle and an outer capsule.

Female Reproductive Organs: Uterus

The uterus or womb is part of the female reproductive system and part of the genitourinary tract. It is characterized by its function as a primary reproductive organ that bears the responsibility of carrying the pregnancy through to term.  At term it utilizes its muscular abilities to expel the mature baby into the world.

Structurally in the non gravid state, the mature uterus is about the size of a woman’s fist, and measures about 8cms X 6cms X 4cms with a volume of about 75-200 ccs, and it weighs 100-200 gms.  It is pear-shaped and is situated between the bladder anteriorly and the rectum posteriorly.  It is a muscular organ with a hollow endometrial cavity.  It consists of a fundus, body (corpus), and neck (cervix).

Histologically, the inner endometrial lining consists of a single layer of columnar cells supported by a thin layer of connective tissue; the middle layer is the thickest and is called the myometrium.  It consists of smooth muscle.  There is a loose connective tissue layer next which is called the perimetrium and then the outer lining is called the peritoneum.

Functionally, it is built to receive the ovum via the Fallopian tubes and the sperm via the cervix facilitates fertilization and provides subsequent housing for the developing fetus.  It enables the implantation of the placenta, so as to facilitate nutritional needs for the fetus, and subsequently functions to expel the mature baby through the vagina into the world.

The cyclical changes of the menstrual cycle present a continual change of events controlled by a series of integrated hormonal events.  During the follicular phase (proliferative phase) which occurs in the first half of the cycle, and after the shedding of the endometrial lining, there is a rise in estrogen which causes the endometrial lining to start to thicken.  In mid cycle after ovulation, luteinizing hormone (LH) is released, which heralds in the luteal phase (also known as the secretory phase). Progesterone now rises and further proliferation of the endometrium occurs.  In the absence of pregnancy, progesterone levels and estrogen levels fall, and the endometrium sheds.

The most common structural diseases of the uterus that may cause pain include fibroid disease, polyps, adenomyosis, cervical stenosis, and carcinoma. The more common disorders are the functional disorders that relate to cyclical events including menstrual cramps, endometriosis, dysmenorrhea, amenorrhea, and menorrhagia. Pain relating to the placement of an Intrauterine Device (IUD) is also relatively common.

The diagnosis is dependent on clinical evaluation, while the most useful imaging modality is ultrasound.

Treatment is dependent on the cause of disease, but includes both medical and surgical techniques.

The Normal Uterus During Follicular (Proliferative) Phase
The longitudinal view of the uterus is depicted by using transvaginal ultrasound. The pear shaped structure, with fundus to the left of the image and lower uterine segment measures 8.7cms in length. The endometrial stripe is seen in the center as an echogenic line and measures about 5mms.
Courtesy of: Ashley Davidoff, M.D.
The Normal Uterus End of Luteal (Secretory) Phase
The longitudinal view of the uterus is depicted by using transvaginal ultrasound.   The endometrial stripe is now seen as three times thicker than in the proliferative phase and measures about 1.5cms.
Courtesy of: Ashley Davidoff, M.D.

Female Reproductive Organs: Ovaries

The pair of ovaries or female gonads are egg producing organs that are connected loosely to the Fallopian tubes and are part of the female reproductive system and part of the genitourinary tract.  They are characterized mostly by their cyclical function and monthly production usually of a single ovum.

Structurally, they are characterized by their almond shape, and measure approximately 3 X 1.5 X 1.5 cms.  They are positioned on either side of the uterus as part of the adnexa in the peritoneal cavity and are found close to the lateral wall of the pelvis, though they are mobile and their position changes.  They are covered and supported by the mesovarium.  Unlike most organs their epithelium is on the outside and is called the germinal epithelium  The deeper layers are called the ovarian cortex and medulla.  The cortex contains follicles, aging corpus lutea, corpora albuginea, and a fibrous stroma.  The medulla only has a stroma.

The Almond
The almond not only has the same shape as the ovary, but also has almost the same size.
Courtesy of: Ashley Davidoff, M.D.

Functionally, the ovaries are the source of the ova and each ovary usually produces one ovum every second month.  They are subjected to the same hormonal influences as the uterus.  During the proliferative phase (follicular phase), the follicles develop, and one of the follicles usually becomes dominant under the influence of estrogen.  At mid cycle, there is a LH surge causing the dominant follicle to rupture and release its egg.  Thereafter, progesterone rises in the luteal phase (secretory phase) and the ruptured follicle becomes a corpus luteum.  If pregnancy ensues, the corpus luteum functions as an early endocrine organ to support the early pregnancy until the placenta takes over.  If there is no pregnancy then the corpus luteum degenerates.

The common diseases that affect the ovary include cysts, hemorrhagic cysts, endometriosis, and carcinoma.  Less common are torsion and metastases.  Ectopic pregnancy more commonly involves the adnexa and Fallopian tubes.  Pain with ovulation is quite common and has been given the name mittelschmerz – the German word for “middle pain” that affects about 20% of women – which for some women is every cycle and for others an intermittent symptom.

The diagnosis of ovarian disease requires the combination of meticulous clinical evaluation and ultrasound.

Treatment of disease depends on the cause and includes both medical and surgical techniques.

Normal Ovary with Follicles
The transvaginal ultrasound shows a normal right ovary in longitudinal view containing black cystic follicles that are all about the same size and are all less than 1cm in diameter.
Courtesy of: Ashley Davidoff, M.D.

 

Female Reproductive Organs: Fallopian Tubes

The Fallopian tubes (also know as salpinges, oviducts) are a pair of tubular structures that are part of the female reproductive system and also part of the genitourinary system.  They are characterized by their delicate and gracile nature and functional importance in fertilization.

Structurally, they are usually about 10cms long (range 7 to 14 cm), and are funnel-shaped.  The widest portion of the funnel is situated laterally, is called the infundibulum, and  is open to the peritoneal cavity. The fimbriae are delicate finger-like processes that surround the opening.  Medial to the infundibulum is the middle and longest portion called the ampulla.  It continues to taper as it progresses medially, and it takes up half the length of the tube with a maximum outer diameter of 1 to 2 cm.  More medial to the ampulla is the isthmus which is also slightly tapered, constitutes about 1/3 of the length, and has an outer diameter of 0.5 to 1 cm.  There is a 1cm long medial intramural portion of the tube called the interstitial portion or cornual portion that connects the tube to the uterus and it has an internal diameter of 1 mms.

Histologically, the tubes are structured like many other tubular organs of the body.  There are three layers; an inner mucosa, intermediate muscular layer and an outer serosa which is continuous with the peritoneum.

Functionally, the tubes act as the site which allows fertilization to take place, and also acts as the transport system that carries the fertilized egg (gamete) to the uterus.

Common diseases include pelvic inflammatory disease (PID) and ectopic pregnancy.  Primary tumors of the tubes are rare.

Treatments  are based on the cause of disease.  Surgical procedures include tubal ligation, salpingolysis, resection and anastomosis and neosalpingectomy.

Hysterosalpingogram and Fallopian Tubes
Courtesy of: Ashley Davidoff, M.D.

Functional Principles relating to Pain Syndrome

The cyclical changes of the female reproductive system involve dramatic monthly events.  Each month the entire endometrium sheds into the endometrial cavity creating strong expulsion waves that can be the source of pain.

In addition, in the middle of the month a rupture of a follicle with its contents extrudes both the ovum and its contents into the peritoneal cavity. Although the cyst is in the 2cms range and the volume of fluid is small, if there is hemorrhage then this can cause significant pain either by enlarging the cyst which in fact may not rupture and pain is caused by distension, (mechanoreceptors), or by rupture and hemorrhage causing sudden distension in a space (mechanoreceptors) or by irritation on the omentum (chemoreceptors).

Blood flow increases to the pelvis and pelvic organs during the cycle and congestive changes can also create aberrant and uncomfortable feeling including pain (mechanoreceptors).

The cyclical changes of hormones and particularly estrogen have been incriminated in the softening on pelvic ligaments that can create lower back pain and pelvic pain.

Most of the pain arises from visceral mechanoreceptors where distension of the hollow organs causes the pain and discomfort.  In the inflammatory diseases, inflammatory mediators lower the threshold for the pain as well as induce pain by causing swelling, and congestion.  Visceral pain, in general, is a dull, deep ache that is poorly localized and often referred.  When the process spreads to somatic structures like the peritoneum, then the pain can become more somatic and thus acute, sharp, and well-localized.

The visceral pain sensations travel along sympathetic afferents in first order neurons and the somatic afferents travel in the peripheral nerves in first order neurons.  They synapse in the dorsal horn of the spinal cord, cross into the contralateral spinothalamic tract, and become second order neurons which travel to the thalamus.  The third order neurons leave the thalamus and connect with the somatosensory cortex, limbic and autonomic nervous systems enabling the perception of the pain sensation and also enabling reactions to the pain to take place on a visceral and emotional level.

Functional Disorders and Diseases

The female pelvis contains many important organs and structures.  Portions of the gastrointestinal tract, urinary tract, as well as reproductive tract are located within the pelvis.  Several of the causes of female pelvic pain involve the derangement in the arrangement of these structures.  The diseases that can cause pelvic pain are innumerable.  We will introduce this section with a classification of the entities that can cause the pain and then will provide some detail on the specifics of each entity.

Acute Debilitating Pelvic Pain – Artistic Rendition
Courtesy of: Ashley Davidoff, M.D.

Causes of Pain

Cyclical Pain

Cyclical pelvic pain can be caused by:

    • menstrual cramps
    • endometriosis
    • mittelschmerz
    • dysmenorrhea
    • premenstrual disorders

Acute Pelvic Pain

There are both gynecological causes of acute pelvic pain and non-gynecological of acute pelvic pain.

    • Gynecologic Causes – Common gynecologic causes of acute pelvic pain include:
      • hemorrhagic ovarian cyst
      • endometriosis
      • pelvic inflammatory disease
      • endometritis
      • ectopic pregnancy
      • spontaneous abortion
      • adnexal torsion
      • degeneration or hemorrhage into a uterine fibroid

Non-gynecological Causes

Non-gynecologic causes of acute pelvic pain include:

      • GI issues
      • appendicitis
      • diverticulitis
      • constipation

Musculoskeletal issues

    • muscle strain
    • stress fractures
    • diastasis of the symphysis pubis

Urinary issues

    • acute cystitis
    • kidney stones and ureterolithiasis

Chronic Pain

    • gynecological
    • endometriosis
    • adhesions
    • fibroids
    • urinary tract issues
    • interstitial cystitis
    • gastrointestinal issues
    • irritable bowel syndrome
    • constipation
    • musculoskeletal and neurological issues
    • mental health issues.

We will now explain in more detail the causes and manifestations of each of the pain syndromes and will start off with the cyclical pains.

Causes of Pain: Menstrual Cramps – Dysmenorrhea

Menstrual cramps or dysmenorrhea are cramps that occur during the menses or more simply, painful menstruation.  They are caused by uterine muscle contractions which serve to evacuate the denuded mucosa and blood clots from the endometrial cavity.  Primary dysmenorrhea is more common but dysmenorrhea may be associated with other pelvic disorders such as endometriosis, adenomyosis, PID, and adhesions, in which case the dysmenorrhea may be more severe or prolonged.

Many women experience tolerable discomfort or pain but when the pain becomes incapacitating, dysmenorrhea may be associated with excessive blood loss and this is known as menorrhagia.

From a structural standpoint, the pain is caused by pressure receptors that sense the increased pressure during muscle contractions, or by chemical receptors that may be incited by ischemia when contractions are excessive and temporary ischemia results.

Functionally, muscle contractions of the uterus are normal and are usually not felt.  If the contractions are sufficiently strong, pressure receptors are activated or ischemia is induced by obstruction of the intramural arteries, causing the pain.

Clinically, the pain presents as cramps during the menses in the lower abdomen, usually in the suprapubic region but may be periumbilical, left or right abdomen, or may radiate down the thighs or occur in the back.  Associate symptoms include nausea, vomiting, headache, weakness or even fainting.  If the pain pattern changes or becomes more severe, or the pelvic examination is abnormal, then secondary causes should be sought and is best done by starting with an ultrasound of the pelvis.

Treatment is commonly with NSAIDS (nonsteroidal anti-inflammatory agents) or a COX-2 inhibitor.  For some patients hormonal contraceptives prove effective.  Secondary causes of dysmenorrhea may require surgery.

Denuded Endometrium
The longitudinal view of the uterus is shown in the ultrasound of this young patient who was having severe pain during her menses.  The images show part of the endometrial lining within the lumen (maroon) with a small amount of blood (bright red) and the remaining endometrial lining (pink).  The denuded endometrium and associated clots cause prostaglandins to be released which induce muscle contraction and these are the primary cause of the pain.
Courtesy of Ashley Davidoff, M.D.

Causes of Pain: Endometriosis

Endometriosis is a disease of the endometrial lining caused by misplaced or ectopic endometrial tissues that are located beyond the uterus and usually results in pelvic pain.

It occurs in 5-10% of women. When endometrial tissue is located outside of the uterus, it can cause pelvic and back pain as well as dyspareunia (pain during sexual intercourse). The potential of endometrial tissue to be denuded into the peritoneal cavity is based on the connection of the cavity with the peritoneal space via the fallopian tubes.

From a structural standpoint, endometriosis commonly affects the ovaries but also can affect the broad ligaments, Fallopian tubes, uterosacral ligaments, cul de sac, or other locations in the pelvis or abdomen, including the ureters and the bowel serosa.  Endometriosis is rarely more far reaching including the kidneys, brain, diaphragm, and pleura.  When it involves the diaphragm or pleura, shoulder pain may be associated with the entity.  Catamenial pneumothorax is pneumothorax induced by the menstrual cycle and implies endometriosis of the pleura.

The nodules can be red-blue to yellow-brown in color, (chocolate cysts) and occur just below the serosa of the organ to which they are attached.  As the lesions undergo recurrent hemorrhage, they can become associated with fibrosis.

Clinically, the entity more commonly occurs in nulliparous women (women who have borne no children) and the degree of pain is variable.  As endometrial tissue, it is responsive to the cyclical hormonal fluxes and thus may bleed in response to hormonal changes and so pain commonly occurs at the time of the menses.  The volume of ectopic endometrial tissue does not correlate with the severity of the pain.  The pain is usually recurring and commonly, but not necessarily, occurs during the menses. With induction of fibrosis, pain may be caused by other structural changes that are unrelated to the menses.

Diagnosis is suspected clinically and confirmed by ultrasound or MRI.  Endometriomas have a characteristic appearance.  Microscopic deposits which may cause symptoms may not be identified by imaging techniques and may only be seen laparoscopically.

Treatment options depend on patient preference, including whether fertility is desired, but include both medical and surgical options.  Medical management frequently involves suppression of regular menses/hormones and surgical options typically attempt to remove endometrial tissue or surgical menopause (i.e. oophorectomy and hysterectomy).

Endometrioma Left Ovary
25-year-old female presents with painful menses. The ultrasound shows a cystic mass in the pelvis with a large amount of debris in the cystic cavity consistent with a chocolate cyst. Although the appearance is consistent with endometriosis, a hemorrhagic cyst is possible and the distinction may only be made pathologically.
Courtesy of: Ashley Davidoff, M.D.

Causes of Pain: Adenomyosis

Adenomyosis is a disease of the endometrial lining caused by misplaced or ectopic endometrial tissues that are located within the uterus and results in pelvic pain and uterine enlargement.  The exact cause of the displacement is not known but it is presumed that a breach in the endometrial myometrial barrier enable a small amount of endometrium to translocate and remain viable.

Clinically, the patient presents with dysmenorrhea and menorrhagia and on exam the uterus is enlarged.

The diagnosis is best made by MRI which shows a thickened junctional zone (>10-12 mms) of the uterus. The deposition of acute blood, blood degradation products such as iron, or the presence of fluid-filled microglandular deposits in the junctional zone make the MRI findings highly specific for the diagnosis.

Treatment options include pain management with NSAIDs and hormonal manipulation.  Surgery and hysterectomy is the only current option for cure.

Causes of Pain: Mittelschmerz

Mittelschmerz is the German word for “middle pain” and refers to the lower abdominal and pelvic discomfort associated with ovulation, which occurs in the middle of the menstrual cycle.  The cause of the pain may be due to the actual follicle rupturing, follicular distension, the contraction of the fallopian tube, or the release of blood/fluid from the ruptured follicle into the abdominal or pelvic cavity.

From a structural point of view it usually is considered a visceral pain caused by stimulation of pressure receptors in the ovary, but the proximity and intimate relationship of the ovary to the peritoneum and release of fluid and blood into the peritoneal cavity may cause irritation of chemical receptors in the peritoneum, inciting somatic-like pain.

Functionally, it is a cruel mechanism that allows a woman to mark the time for potential fertilization, or on the other hand to abstain from intercourse if fertilization is not desirable.

Clinically, the pain classically occurs in the middle of the month, lasts between 6-8 hours but may last up to 2-3 days, occurs suddenly, is situated on one or the other side of the pelvis, in the midline or sometimes in the back, usually is ill-defined and is either cramp-like or a deep discomfort.   It is not considered a disease state but can sometimes be quite uncomfortable.

The diagnosis rests on the timing of the pain, and the usual pattern of an individual woman, though each cycle can be uniquely different. One may be suspicious of other disorders if the pain is more severe or lasts longer than usual, or if a mass is palpated on pelvic examination.

Ultrasound is recommended if the pain is not classical or if a mass is felt, in order to exclude other causes such as a large unruptured cyst, hemorrhagic cyst, blood in the peritoneum, endometriosis, ectopic pregnancy or torsion.

Management generally is supportive and reassured.  If necessary, pain can be managed with NSAIDs (non-steroidal anti-inflammatory drugs) such as ibuprofen.

Ovulation and Mittelschmerz

Ovulation and Mittelschmerz
The transvaginal ultrasound focuses on the ovary (pink oval structure) of a young woman who was complaining of mid cycle pain. A decompressed Graafian follicle (inverted teardrop shaped yellow structure in the ovary) is seen emptying its contents into the peritoneal cavity, causing a triangular shaped accumulation of fluid in the peritoneal cavity (yellow triangle).  It is the shape of the follicle and its proximity to the fluid in the peritoneum together with the concordant site of the pain that allowed the diagnosis of mittelschmerz to be made.
Courtesy of: Ashley Davidoff, M.D.

Causes of Pain: Premenstrual Disorder

Premenstrual Disorder or Syndrome (PMS) is a group of systemic and local manifestations of the late phase (luteal or proliferative) part of the cycle thought to be caused by abnormal sensitivity to the fluctuation of estrogen and progesterone levels, serotonin deficiency, magnesium or calcium deficiency resulting in physical, psychological and behavioral changes.

Clinically, symptoms occur a few days prior to menstruation and can involve abdominal and pelvic pain as well as mood changes.  Mood changes include irritability, anxiety and depression.  Physical symptoms can include bloating/fluid retention, breast tenderness, headaches, and muscle or joint pain.

The treatment of PMS frequently requires a multidisciplinary approach including medical and non medical treatments.  Non medical approaches include emphasizing regular exercise and adequate nutrition and sleep.  Medical management includes SSRI (selective serotonin re-uptake inhibitor) and antidepressants.

Causes of Pain: Ovarian Cysts

Ovarian cysts (follicles) are normal evolutions of the menstrual cycle but in certain instances the cyst physiology is altered for unknown reasons, causing the cyst to enlarge unusually, rupture in a different manner, or become hemorrhagic, resulting in a pain syndrome.

A variety of situations manifest structurally including:

      • Follicular rupture – mittelschmerz
      • Enlargement of the follicle without rupture
      • Hemorrhage into the follicle/cyst without rupture
      • Hemorrhage into the follicle/cyst with rupture
      • Hemorrhage into an endometrioma simulating hemorrhage into a follicle usually without rupture

The common result is a pain syndrome that commonly occurs in mid cycle.

Physiologically, during each menstrual cycle, a normally functioning ovary produces multiple cysts called Graafian follicles.  During the middle of the cycle, one cyst dominates and releases an egg.  The follicle then becomes the corpus luteum, which can mature to measure up to 2 cm.  If fertilization does not occur, the corpus luteum fibroses and is resorbed.  If fertilization does occur, the corpus luteum matures and enlarges initially, but later shrinks during pregnancy.  Ovarian cysts can be either follicular or luteal (relating to the corpus luteum) and may respond to gonadotropins.

Clinically, the pain is different from mittelschmerz in that it may be more severe, prolonged, or with a different character.  Sometimes the pain can simulate peritonitis.  Most importantly from a diagnostic standpoint, is that a mass is usually felt on clinical examination.

The diagnosis is confirmed by ultrasound which usually shows a cystic mass in the adnexa.  The cyst is either larger than the usual follicle, contains hemorrhage, or hemorrhage and large amounts of fluid are noted free in the pelvic cavity.  When the patient presents with peritonism, a CT scan is usually indicated and in the case of a ruptured cyst, induration of the greater omentum or proximity of the bleed to the anterior peritoneum is recognized together with the hemorrhagic cyst.  When an ovarian cyst ruptures, there is usually minimal blood loss.

Treatment depends on several factors.  In most patients, the treatment is conservative with pain management being central to the care.  Surgery may be indicated if the cyst does not go away after several periods or is enlarging.   In a post menopausal woman, when complex cysts are identified, cyclical disease is not a consideration and malignant disease must be suspected

Normal (a) and Large Unruptured Follicles (b)
The ultrasound shows a normal left ovary with small Graafian follicles (a) and an enlarged ovary with two unruptured simple cysts (b). The latter study is from a 46-year-female who presents with pelvic discomfort. The transvaginal ultrasound (b) shows a large 6cms ovary that contains two cysts each about 2cms in size. The ovary is about twice to three times normal in size and the distension presumably causes the discomfort. The cysts are simple in nature without hemorrhage.
Courtesy of: Ashley Davidoff, M.D.
Acute Hemorrhage – Right Adnexa Cyst
26-year-old female presents with acute midcycle right lower quadrant pain without a fever, associated with peritonism in the right lower quadrant.  Differential diagnosis included appendicitis, ruptured cyst, torsion, endometrioma and ectopic pregnancy, but her HCG was normal.
The CT scan shows a cyst in the right adnexa consistent with a hemorrhagic and ruptured follicle, (maroon nodule with a pink circle in b), but also shows a large amount of blood and fluid, some accumulating in the right lower quadrant, (light pink anteriorly on right in b) some in the cul de sac (bright red sediment, and light pink supernatant in b) and some in the greater omentum on the right side (maroon in d).  It is the latter component that incites the somatic nociceptors of the peritoneum to simulate peritonitis. The patient was treated conservatively and improved over the next 24-48 hours.
Courtesy of: Ashley Davidoff, M.D.

Causes of Pain: Pelvic Inflammatory Disease (PID)

Pelvic inflammatory disease (PID) is a sexually transmitted infection of the upper female genital tract which is usually caused by a polymicrobial group that includes Chlamydia and/or Neisseria gonorrhea (GC) and results in salpingitis, endometritis, and may be complicated by tubo-ovarian abscess.  The infection often starts at the cervix and travels upward.  Possible complications include infertility and ectopic pregnancy.

The diagnosis usually rests on the clinical presentation which includes fever, vaginal discharge, and acute pelvic pain and may be complicated by shock.  Cervical tenderness is characteristic on examination.  Imaging is not usually warranted unless a mass is felt on examination or the patient fails to improve on medical therapy.

Depending on the severity at presentation, treatment is with either oral or IV antibiotics.  Management ideally is initiated even prior to results of cultures, which otherwise would delay treatment.  A high index of suspicion is required and there are guidelines for empiric antibiotic coverage, typically to cover gonorrhea and Chlamydia along with other common pathogens. (CDC). Those with mild to moderate symptoms may be treated with oral antibiotics unless there is concern they will be unable to complete this therapy, then they should be hospitalized.  Patients with more severe infection, or abscess, should be hospitalized for potential antibiotics.  Likewise, if another serious etiology such as appendicitis can’t be excluded, the patient should be hospitalized.

Prevention includes routine screening for GC and Chlamydia for at-risk groups.

Left Ovarian Abscess
The CT is from a 36-year-old female recently post cesarean section who developed pain in the left lower quadrant, with fever and rigors.  She has a known fibroid uterus but a new tender mass was found in her left adnexa. The CT scan shows a large cystic collection in the left adnexa (dark yellow) with an enhancing rind. Pus was aspirated under ultrasound guidance, and a diagnosis of an ovarian abscess was made. She was treated on antibiotics and subsequently her pain and fever resolved.  The axial view (a,d) shows a 10.7 cms abscess.  The coronal view (b,e) shows the large abscess in the left adnexa with a smaller abscess just below it (yellow) adnexa with the uterus and its endometrial cavity(maroon) and a fibroid in orange.  The sagittal view (c,f) shows an irregular uterus (pink) with endometrial cavity (maroon) and a few fibroids (orange).
Courtesy of: Ashley Davidoff, M.D.

Causes of Pain: Endometritis

Endometritis is an inflammatory condition of the endometrium and can be acute or chronic.  The most common cause is infection, staphylococcus aureus, and streptococcus.  Acute infection is most commonly seen in postpartum period, after a prolonged labor, following cesarean section, and premature rupture of membranes.

The most common causes of chronic endometritis is PID, but may be caused by retained products of conception such as an Intrauterine Device (IUD).  Pyometrium is a form of chronic endometritis.

Clinically, the patient with acute endometritis presents with pain, fever, vaginal discharge and bleeding  The patient with chronic endometritis presents with vague discomfort or chronic pain, sometimes with a blood stained discharge.

The clinical symptoms are characteristic and usually the diagnosis is made clinically, particularly in the obstetric population where clinical suspicion is high.  If the patient does not respond to antibiotics within 48-72 hours, then imaging to exclude an abscess, or retained products is warranted.  Ultrasound is the procedure of choice, and it is able to identify abscesses and retained products but cannot confirm endometritis. If thrombophlebitis is considered, then CT or MRI would be helpful.

Treatment is initially with antibiotics but if an abscess is identified it requires drainage, and if retained products are identified then dilatation and curettage is necessary.

Normal
Endometritis
The CT scan through the pelvis in the top image shows a heart shaped fluid-filled endometrium with no enhancement of the mucosa and this patient was normal except for a focal probable physiologic process in the left adnexa and a small amount of free fluid in the right pararectal space. The bottom image is from a 20-year-old female with severe colitis who demonstrates an enhancing endometrium that is suggestive of acute endometritis. In addition, she has a large amount of ascites allowing us to visualize both ovaries and broad ligaments.
Courtesy of: Ashley Davidoff, M.D.

Causes of Pain: Ectopic Pregnancy

Ectopic pregnancy is a disorder where a gestation is located in a location other than the uterus, most commonly in a Fallopian tube, but can occur on an ovary or intra-abdominally.   It is characterized by acute pelvic pain associated with vaginal bleeding and a positive pregnancy test. There are multiple predisposing factors, including those which alter the structure and function of the Fallopian tubes.  These include previous ectopic pregnancy or Fallopian tubal surgery, or PID.  Other factors include cigarette smoking, use of fertility drugs and previous use of some intrauterine devices, and of course being a female of childbearing age.  For unclear reasons, females over the age of 35 are also at higher risk for ectopic pregnancy.  Ectopic pregnancy can result in serious complications including hemodynamic instability and death.

The diagnosis of ectopic pregnancy involves a complex but standardized approach.  This involves a careful history and physical examination and a high index of suspicion along with appropriate laboratory studies and imaging. The diagnosis is suspected clinically by a positive pregnancy test, pelvic pain, and/or vaginal bleeding.

An ultrasound is the preferred imaging technique and correlated with a quantitative hCG can be diagnostic of ectopic pregnancy.  An ectopic is suspected if the hCG is greater than 1500 and there is no evidence of an intrauterine gestational sac on transvaginal ultrasonography.  On, transvaginal ultrasonography, an ectopic is suspected if an intrauterine pregnancy is not detected with a hCG level of greater than 6500.

The classic presentation of ectopic pregnancy includes amenorrhea (no periods for more than 6-7 weeks), pelvic pain, and vaginal bleeding.  Many patients do not have this classic presentation, however.  Anytime a woman presents with pelvic or abdominal pain associated with amenorrhea, one must consider ectopic pregnancy.  A positive pregnancy test along with a normal or slightly enlarged, often tender uterus or adnexal mass is highly suggestive of ectopic pregnancy.  However, no combination of physical findings can definitively diagnose an ectopic pregnancy.

Treatment options depend on whether the patient is hemodynamically stable, but include expectant management, medical and surgical management.

Generally, the prognosis of ectopic pregnancy is good if it is diagnosed in a timely fashion.  However, this serious condition is also one of the most common causes of maternal death and infertility.

Hysterosalpingogram and Normal Fallopian Tubes
Shown is a hysterosalpingogram demonstrating the Fallopian tubes in pink.
Courtesy of: Ashley Davidoff, M.D.

Empty Uterus
This 32-year-old female presents with abdominal pain and pelvic pain with a positive HCG uterus and no intrauterine pregnancy.  There was complex free fluid in the cul de sac probably blood and hemorrhage seen in the top right hand corner of image a.  In image b a normal left ovary was identified and in image c a viable fetus was seen in the left adnexa with fetal Doppler flow and a heart beat.  In image d a crown rump length of .62 cm was measured corresponding to a gestational age of 6 weeks and 4 days.  The findings are consistent with a diagnosis of a left sided ectopic pregnancy.
Ashley Davidoff MD

Causes of Pain: Spontaneous Abortion – Miscarriage

Spontaneous abortion or miscarriage is the expulsion of a non viable embryo or fetus usually caused by chromosomal aberrations or environmental factors, occurring before the 20th week, though most occur before 12 weeks.  There are four clinical entities including: threatened, inevitable, incomplete and complete spontaneous abortion.

Clinically, threatened abortion is diagnosed and characterized by some bleeding and sometimes accompanied by pain in the first trimester.  About half of these patients will recover and proceed to full term pregnancies. When the symptoms are accompanied by a dilated cervix, then abortion becomes “inevitable”.  Bleeding and cramps are usually more prominent with inevitable abortion.  The presence of products of conception in the discharged blood warrants examination by ultrasound.  If products of conception are identified in the endometrial cavity, the diagnosis is compatible with incomplete abortion and their absence confirms the diagnosis of a complete spontaneous abortion.  Pain and bleeding subside when the abortion is complete.

Treatment depends on the stage of the spontaneous abortion.  A complete abortion requires no further treatment.  An incomplete or inevitable abortion before 13 weeks is treated with suction dilatation and curettage though medical therapy (misorostol) can be used.

Retained Products of Conception
This ultrasound is from a 46-year-old patient who presents with bleeding and pain nine weeks into her pregnancy. The Doppler study shows no fetal pole or fetal heart beat.  Findings include a thickened endometrium (light pink) with a focal area in the posterior and fundal portion of the endometrium (dark pink with red blood vessel inside) that enhances, consistent with retained products of conception and spontaneous abortion.
Courtesy of: Ashley Davidoff, M.D.

Causes of Pain: Ovarian Torsion

Adnexal (ovarian) torsion is a twisting of the ovary around its pedicle including its neurovascular bundle, usually caused by an associated benign tumor, resulting in an acute pain syndrome.  There may be spontaneous untwisting with symptomatic resolution or progressive venous congestion, followed by arterial compromise.  Torsion may be complicated by hemorrhagic infarction.

The diagnosis is based on the clinical presentation of acute severe lower abdominal pain and tenderness often associated with nausea and vomiting usually in a young female or in post menopausal woman.  Torsion is also seen with increased frequency during pregnancy, and the diagnosis is confirmed using ultrasound which shows a twisted vascular pedicle (“whirlpool” sign) and lack of flow to the ovary.  The ovary is swollen.

Treatment includes urgent laparoscopic evaluation to determine viability and if the ovary looks viable, then the pedicle is untwisted and pexied to prevent recurrence.  If infarction has occurred, then the ovary needs to be removed.

Causes of Pain: Fibroid Disease and Degeneration

Uterine fibroids (leiomyomas) are benign tumors of the myometrium and are the most common female reproductive tract tumor.  They are thought to arise from a single cell and growth is affected by estrogen and progesterone.  They typically regress with menopause.

They occupy space and in so doing may displace or obstruct other structures. They may cause pain during the menses and if they degenerate with disruption of their blood supply, sudden severe pelvic pain can occur.   If a pedunculated fibroid becomes twisted on itself (torsion), this can cause acute pain.

Symptoms associated with these space occupying lesions can include irregular or prolonged menstrual bleeding, painful intercourse, and pressure on other structures located nearby including the bladder (urinary frequency) or bowels (constipation.)

Treatment depends on the clinical scenario, but usually for the pain syndromes it is symptomatic.  Frequently, fibroids are incidental findings which can be managed expectantly.  If there is significant pain suggestive of necrosis, bleeding, or infertility, surgery may be considered.  Options include myomectomy (removal of the tumor only) or complete hysterectomy.  Sometimes, selective embolization is used, particularly when the fibroids are large.  This is a percutaneous technique that involves selective catheterization of the feeding arteries and causing ischemia and infarction of the tumor.

Prolapsing Submucosal Fibroid
This patient presented to the emergency room with severe crampy abdominal pain and a known history of a submucosal fibroid. The MRI shows the fibroid (dark pink) protruding and expanding the cervix in the sagittal view, and in the coronal view it is seen as a hyperemic structure (c) surrounded by lighter pink myometrium.
Courtesy of: Ashley Davidoff, M.D.

Non-Gynecological Causes of Acute Pain

There can also be non-gynecological causes of acute pain in the pelvis generated by gastrointestinal disorders which include:

      • appendicitis
      • diverticulitis

Acute pelvic pain can be generated by musculoskeletal disorders  or by the urinary system.

Non Gynecological Causes of Acute Pain: Appendicitis

Appendicitis is an inflammatory condition of the appendix caused primarily by an initial obstruction with secondary infection, distension, and subsequent infarction and rupture. The appendix is a long tube-like structure (diverticulum) which extends from the cecum.  The obstruction may be caused by lymphoid hyperplasia (often related to a viral illness), foreign bodies and fecaliths, or related to Crohn’s disease.   Acute appendicitis is the most common surgical emergency in the Western World. It typically affects teenagers and young adults, though may occur in younger children and infants. There is a smaller secondary peak in the elderly.

The appendix is situated in the right lower quadrant but its origin off the cecum is quite variable so that it may be anterior, medial or posterior to the cecum.  Its length also varies, so, for example, a very long retrocecal appendix may reach to the right upper quadrant.  Depending on the anatomic location of the appendix, it may be initially difficult to differentiate from other causes of acute pelvic pain

Clinically, appendicitis classically presents with abdominal pain that starts at the umbilicus and migrates to the right lower quadrant.  It is usually associated with systemic symptoms and signs such as nausea, vomiting, and fever.  The pain almost always precedes the vomiting.  On examination there is usually tenderness with guarding and rebound in the right lower quadrant at Mc Burney’s point, and rectal examination usually reveals right sided pelvic tenderness.  Systemically, mild dehydration, fever and an elevated white cell count are associated signs.  (Family Practice Notebook).  The classical pain only occurs in about 50% of patients. When the patient presents with these classical features, there is no reason to go any further with imaging to confirm the diagnosis.  However, appendicitis is notoriously a masquerader from being relatively asymptomatic to having severe visceral and somatic pain.

When clinical findings are equivocal, diagnostic imaging choices including ultrasound and CT scan are considered.  In children, and young thin females, ultrasound is the study of choice.  Ultrasound is extremely dependent on the operator, and also is made difficult if bowel gas is present.  In the older population, CT is preferred.  The overall accuracy of US for appendicitis is reported at 70-95% and for CT accuracy is 93-98%.   CT is indicated when perforation or peritonitis is clinically suspected.

Treatment is surgical.  Laparoscopic removal is frequently utilized.  Sometimes, open laparotomy is required, such as when an associated abscess is suspected.

Gross Pathology showing a Normal Lily White Appendix (left) and a Pus Filled Black Necrotic Appendix (right)
Courtesy of: Ashley Davidoff, M.D.
Appendicitis
This is a CT scan of a young man presented with severe somatic pain, well-localized to the right lower quadrant. He did not have a fever but had a mildly elevated white cell count. The CT shows an appendix that has a diameter of 8mms. and  is distended with fluid (yellow in (b) and (d) is surrounded by a hyperemic rim (white rim in (a) and (c) – pink around the yellow in (b) and (d) significant induration of the pericolic fat,  (maroon) and thickened peritoneum (bright red). It is the latter involvement of the peritoneum that causes the severe well-localized somatic pain.
Courtesy of: Ashley Davidoff, M.D.

Non Gynecological Causes of Acute Pain: Diverticulitis

Diverticulitis is an inflammation of a diverticulum caused by an initial obstruction and then infection of the diverticulum. This results in spread of the inflammation to the surrounding fat and other tissues or organs surrounding the bowel.  Diverticulitis can be complicated by abscess formation, bowel perforation, peritonitis or less commonly by fistulous formation to the bladder.

Diverticula occur at sites of the colon wall that are relatively weak, typically at sites of the insertions of blood vessels through the muscle wall. Its lumen communicates with the lumen of the colon.  Although not completely understood, these outpouchings are much more common with a Western, low fiber diet and appear to be related to increased intraluminal pressure.  Diverticulitis is a condition that most commonly involves the sigmoid colon and therefore presents with left lower quadrant pain which occasionally can be confused with other pelvic pathology.  Most colonic diverticula are 0.5 to 1 cm in diameter, typically located in the sigmoid colon.

Clinically, the patient classically presents with left lower quadrant pain because the sigmoid colon is the most common site of involvement.  The descending colon is sometimes affected, in which case the patient will present with left upper quadrant or left mid or lateral pain.  Pain is often present for several days, and there may be a history of prior similar episodes. Fever and elevated white count are common accompaniments.  It is sometimes associated with changes in bowel movements.

The diagnosis is confirmed by a CT scan, which is the study of choice. Oral and intravenous contrasts are preferred, but not essential, if there is a contraindication. Administration of rectal contrast may be considered in such cases and may slightly improve sensitivity by dilating the colon. The reported sensitivity of CT for diagnosing acute diverticulitis is 79-99%. CT is excellent for detection of complications of diverticulitis including abscess and fistula formation; furthermore, it may detect other non-colonic causes of abdominal pain.  CT is able to direct management, since uncomplicated diverticulitis would be managed conservatively and when complications such as abscess formation or perforation are identified, they would be managed surgically.

Diverticulitis  is commonly treated with antibiotics, but sometimes surgery is required.  Depending on the severity, the condition is medically managed with oral or parenteral antibiotics which provide broad coverage.  This coverage needs to include anaerobes.  Sometimes this can be done as an outpatient with oral medications.  But for more severe cases, including those associated with vomiting, intractable pain, or associated abscess, they are managed in the hospital with IV antibiotics.  Large abscesses can be drained percutaneously, while surgery is sometimes required for abscesses associated with perforation and free air.  For frequent recurrences, sometimes the portion of the affected bowel is removed electively, after the acute inflammatory process settles down.

Non-inflamed Diverticulum (a, b) green), Diverticulitis (c, d), and Pericolic Inflammation (red)
The CT scan shows evidence of both diverticulosis and diverticulitis. In images (a) and (b), two small non-inflamed outpouchings are seen. The diverticula are outlined in green in (b). In the same patient, another diverticulum has become inflamed, and diverticulitis is present. This is characterized by induration of the fat around the diverticulum and the colon (maroon) and extension of the inflammatory process to the peritoneal lining (bright red in (d). Inflammation of the colon and colonic wall induces visceral pain which is an ache and poorly localized, and inflammation of the peritoneal lining causes a sharp, well-localized somatic pain that is sensitive to deep palpation.
Courtesy of: Ashley Davidoff, M.D.

Acute Pelvic Pain Generated by the Musculoskeletal Disorders

Acute muscle strain includes injuries such as acute groin strain that is caused by running, jumping or twisting that results in external rotation or sudden contraction and puts strain by overstretching the adductor longus muscle.  The event is marked by a sudden twinge or tearing sensation during the stress and is easily recognized by the patient and relatively easily diagnosed.  Treatment is with NSAIDs and rest.

There are musculoskeletal causes of acute hip injury that include sprains of the hip joint caused by exceeding the range of motion of the hip joint.  Injuries that may do this include a force from an opponent in a physical contact sports game or by trunk force that is in the opposite direction of a planted foot.  Clinical exam shows pain which increases with hip rotation, inability to circumduct the hip.  Treatment is with NSAIDs and rest.

Stress fractures of the inferior pubic ramus, femoral neck or subtrochanteric area of the femur are caused by repetitive stress (running)  manifesting as groin pain or an aching sensation in the upper thigh that increases with activity and improves with rest.  Clinically, the patient cannot stand on one leg and deep palpation results in point tenderness. X-ray, bone scan and MRI are required to confirm the diagnosis. Treatment requires rest for 2-5 months and usually requires a crutch. Snapping hip phenomenon is commonly seen in dancers, gymnasts and hurdlers, where repetitive movements lead to muscle imbalance.

Direct blows to the hips may result in contusion of the iliac crest or abdominal musculature and these may result in pain caused by hematoma, or muscle spasm. This can last from 1-3 weeks.  Treatment is with NSAIDs, ice pads, and rest.

Diastases of the pubic symphysis is a common association with pregnancy where the combination of ligamentous laxity and stresses induced by labor cause permanent diastasis and acute pain.  Additionally, diastasis may be caused by high energy trauma, as is seen in horse riders who by virtue of stretching of the pubic symphysis, insult to injury.

Acute Pelvic Pain Generated by the Urinary System

Acute pelvic pain can also be generated by the urinary system.

Acute Cystitis

Acute cystitis is an inflammatory condition of the bladder usually caused by coliform bacteria, usually E Coli,  transferred from the bowel to the bladder via the urethra.  Non infectious causes are also present such as interstitial cystitis and eosinophillic cystitis.  It is common in females who are sexually active, (honeymoon cystitis) but sometimes seen in young females with a second peak in the older women.  It is rare in males.

Structural Considerations.  The proximity of the rectum to the urethra together with the short urethra of women, enable coliform bacteria to enter and infect the bladder.  In the young and old, uncoordinated and inappropriate cleansing of the area may cause the infection and the mechanical consequences of sexual intercourse may be the cause in honeymoon cystitis.  Normal bladder function and excretion of urine enable bacteria to be removed by the evacuation but if the patient has bladder stagnation and there is difficulty with urinary evacuation then infection becomes more likely.

Clinically, cystitis commonly results in dysuria (painful urination), urinary frequency, cloudy urine, and possibly hematuria (blood in the urine).

Urine testing in the lab enables the diagnosis by identifying white blood cells, red blood cells, and may be able to culture the bacteria with a clean catch specimen.

Treatment with antibiotics is instituted if bacteria are identified.  Pyridium is used to reduce the burning and pain and fluids are encouraged to increase flushing of the bladder.

Acute Pelvic Pain Generated by the Urinary System : Kidney Stones

Renal colic is an acute pain caused by acute obstruction of the urinary collecting system by a stone that has become dislodged from the kidney and becomes lodged in the ureter.  Ureterolithiasis is most commonly a spontaneous event but is sometimes associated with decreased fluid intake, dehydration and subsequent urinary concentration.  It is also associated with increased intake of oxalates.

Clinically, the pain syndrome that results is classically associated with flank pain, or “loin to groin pain”, though isolated groin pain is possible.  The pain is usually excruciating and possibly the most severe pain the patient has experienced.  Hematuria is very common.

A CT scan without contrast is the imaging study of choice for a patient suspected of having kidney stones.

When the stone is small (<5mms), conservative treatment is usual which includes analgesia and hydration.  Retrograde retrieval and/or stenting of the system is reserved for larger stones or stones that do not respond to conservative therapy.

Chronic Pelvic Pain

Chronic pelvic pain is pain that has been present for longer than three months.  It is a poorly understood debilitating disorder with multiple causes.  Many of the diseases, discussed above can progress to a chronic condition, and the classification into gynecological, gastrointestinal, urinary, and musculoskeletal causes is similar.

Clinically, a careful history directed at the prior medical and surgical history is essential.  Direct questioning related specifically to the genitourinary system, gastrointestinal system and musculoskeletal system is necessary, and probably the most important component of the diagnostic workup. Prior histories of fibroids, endometriosis, PID, ectopic pregnancy, are all diseases that may progress to a chronic pelvic pain syndrome.

If the clinical examination reveals unexpected findings such as a mass, then diagnostic imaging by ultrasound may be helpful in the workup.

Treatment depends on the known cause but if a structural abnormality is not identified or is not amenable to surgical or specific medical intervention, then recommendations include prudent use of alpha blockers, directives allowing release of myofascial trigger points, and anxiety control.

We will outline a few more of the common disorders associated with chronic pelvic pain that have not been outlined above.

Chronic Pelvic Pain: Pelvic Adhesions

Pelvic adhesion is the fibrotic consequence of inflammation in the pelvis that may have been caused by previous surgery, pelvic inflammatory disease, complications of diverticulitis or recurrent intraperitoneal bleeds caused by cyclical events or endometriosis.

The result is that the fibrous tissues cause structural distortion and entrapment of the pelvic organs causing pain and dysfunction.

Clinically, the patient presents with visceral type pain that is characteristically poorly localized in the lower abdomen, with an aching or cramping character.  The diagnosis is based on the clinical history and unless frank obstruction of the gastrointestinal or genitourinary system is observed radiologically or laparoscopically, it is a diagnosis of exclusion.

Treatment is somewhat controversial but sometimes surgery for lysis of adhesions is helpful.

Chronic Pelvic Pain: Irritable Bowel Syndrome

Irritable Bowel Syndrome (IBS) is a debilitating functional gastrointestinal disorder characterized by abdominal (and pelvic) cramping, increased bowel gas, and bowel movement changes including diarrhea and/or constipation.  The cause is mostly unknown, but the syndrome may be initiated by an infection and sometimes has psychological origins.

Clinically, the presenting symptoms are non specific.  The pain ranges from mild to severe, the bowel habit may manifest with constipation or diarrhea, there may be a sense of incomplete evacuation, bloating and abdominal distension.  These symptoms simulate many other disorders including inflammatory bowel disease, celiac disease, giardiasis, Yersinia enterocolitica and these need to be excluded before the diagnosis is considered.  It is thus a diagnosis of exclusion.

Treatment includes symptomatic relief, dietary intervention, and when indicated, psychological evaluation and assistance.

Chronic Pelvic Pain: Constipation

Constipation is the presence of hard feces that is difficult and painful to evacuate.  This usually occurs when the patient evacuates less than three times per week.

In general, constipation is caused by dry stool.  When the transit time of the stool through the colon is slowed, there is excessive absorption of water from the stool making it hard and dry and difficult to evacuate.  There are many causes for this slowing, including age, mental status, dietary factors, hormonal factors, and side effects of medications (morphine and other opiates).   The gradual accumulation of feces can be complicated by abdominal distension and finally impaction and obstruction which becomes a surgical emergency.

Functional considerations; Because the pelvis contains a portion of the colon, the cramping and pressure associated with constipation can cause pelvic pain both by pressure on neighboring structures as well as referred pain.

Clinically, the patient complains of difficult, painful, infrequent and ineffective evacuation.  Small fecal pellets may be passed but this is overall an ineffective evacuation.

The diagnosis is made clinically but the presence of large amounts of stool distending the colon is easily diagnosed by a plain film of the abdomen, while complications are best diagnosed by CT scanning.

There are multiple therapies for constipation.  Frequently, if the constipation is severe enough to present for medical attention, more aggressive approaches such as enemas are employed.  Multiple over the counter laxatives are available for less severe cases.  High fiber diet and adequate hydration should also be emphasized.

Normal Rectum (above) and Impacted Rectum (below)
The CT scan shows a patient with a normal empty rectum that contains a few bubbles of air (a, b) overlaid in dark orange, and a patient with severe constipation and impaction of feces (c), and (d) overlay in brown) It is even painful to look at.
Courtesy of: Ashley Davidoff, M.D.

Chronic Pelvic Pain: Interstitial Cystitis

Interstitial cystitis is a chronic inflammatory disorder of the bladder mucosa.

The cause of interstitial cystitis is unknown, although it is thought to be a syndrome which may have multiple etiologies:  autoimmune, infectious, and allergic components.

Clinically, symptoms can be very similar to that of acute cystitis and urinary tract infection, so that increased urinary frequency, urgency, dysuria and hematuria are common manifestations.

There is no evidence of infection on culture.

Medical management and support groups are usually instituted.  Medications include tricyclic antidepressants and antihistamines. It is also recommended that interstitial cystitis patients avoid caffeine, acidic foods, and artificial sweeteners. Occasionally, medications are infused directly into the bladder.  Surgery is rarely indicated.

Chronic Pelvic Pain: Myofascial Pain Syndrome

Myofascial pain is a chronic pain syndrome that is poorly understood, but thought to be caused by altered focal pain thresholds in the muscle.  It is characterized by the presence of specific trigger points which are sensitized and sensitive foci in the muscle and fascia.  It may be closely related to fibromyalgia.

Clinically, these areas exhibit extreme tenderness since the receptors are a mixture of both somatic and visceral nociceptors.   It is usually associated with other symptoms including headaches, fatigue, and depression.

Treatment is non surgical.  Myofascial release is a soft tissue treatment that uses gentle massage and stretching of muscle and fascia that has shown to be effective.

Chronic Pelvic Pain: Mental Health Disorders

Mental health disorders including sexual abuse, substance abuse and depression can be associated with chronic pelvic pain.  (Walker)

The Large Picture of Pelvic Pain

As with all medical evaluations, the history is a most important tool to help establish the cause of the pelvic pain.  As discussed above, the timing (acute, cyclical, chronic) frequently is useful in diagnosis. Vaginal discharge or bleeding may make several conditions more likely.  Associated symptoms such as urinary or gastrointestinal changes may suggest an etiology other than a gynecological one.  History can provide important clues as to the etiology of the pelvic pain.  Characteristics such as location, quality, radiation, severity, and duration along with any aggravating or alleviating factors are important to ascertain.  Likewise, timing with attention to the relation to menses, bowel movements, urination, and sexual intercourse might suggest a particular pathology.

There are certain clinical pointers on the clinical examination that are very helpful in making a diagnosis.  An important physical exam finding in pelvic inflammatory disease is cervical motion tenderness, or uterine or adnexal tenderness on bimanual exam.  Frequently, there is evidence of infection with mucopurulent discharge, fevers, and increased numbers of white blood cells on microscopic evaluation of saline washings of the vagina.

Ectopic pregnancy may have a classic presentation that includes amenorrhea (no periods for more than 6-7 weeks), pelvic pain, and vaginal bleeding and a positive pregnancy test.  Many patients do not have a classic presentation, however.  Anytime a woman of childbearing age presents with pelvic or abdominal pain associated with amenorrhea, one must consider ectopic pregnancy.  A positive pregnancy test along with a normal or slightly enlarged, often tender uterus or adnexal mass is highly suggestive of ectopic pregnancy.  However, no combination of physical findings can definitively diagnose an ectopic pregnancy.

In the setting of sudden onset of severe adnexal pain or mass, associated with nausea and vomiting, ovarian torsion must be excluded on an emergent basis using ultrasound.  Time is critical in this disease and the presentation of pain does not necessarily imply ischemia.

The Large Picture of Pelvic Pain: Lab Evaluation

Lab evaluation should always include a pregnancy test in all patients of childbearing years.  There are certainly times when either the patient is unaware they are pregnant or do not want others to know that they are pregnant, and missing this diagnosis could be fatal.  The most commonly performed pregnancy test is either the urine test or serum testing for human chorionic gonadotropin (hCG).  hCG is a pregnancy hormone initially produced by the embryo and later the placenta. It helps maintain the corpus luteum which is necessary to produce progesterone, which in turn is essential for the pregnancy.  Urine pregnancy testing can detect hCG levels as low as 20 mIU/ml (in theory) versus serum testing which can detect levels as low as 5 mIU/ml.

Testing for gonorrhea and Chlamydia is mandatory, and given increased risk, the patient should also be tested for HIV.

The Large Picture of Pelvic Pain: Imaging

In general, ultrasonography is the first investigative study of choice if a gynecologic problem is suspected. It allows for excellent visualization of the pelvic organs, is relatively inexpensive, and does not expose the patient to ionizing radiation. The use of a transvaginal probe also obviates the need for a full bladder and allows for exquisite detail of the anatomy and pathology.

Other studies used in the evaluation of pelvic pain include sonohysterography. Sterile saline is injected into the uterine cavity, and transvaginal ultrasound is used to evaluate the endometrial cavity. Polyps, submucosal fibroids, and endometrial cancer may be delineated.

CT is of use in several clinical situations. It may be performed if ultrasound findings are equivocal, if the abnormality is beyond the field of a transvaginal probe, or if a non-gynecologic cause of pelvic pain is suspected. CT is particularly important in evaluating suspected pelvic abscesses or hematomas, postpartum complications, complications related to pelvic inflammatory disease, or to exclude bowel disease.

MRI allows for excellent visualization of soft tissue structures with multiplanar views. It is helpful for diagnosing endometriosis and determining the origins of adnexal masses as well as bony and soft tissue injury of muscle.  It is the best imaging modality to diagnose adenomyosis and distinguish it from uterine fibroids. It may also demonstrate pelvic varices/venous congestion, though there is scant data evaluating accuracy, sensitivity and specificity.

Hysterosalpingography (HSG) involves injecting radiopaque contrast through the cervix and using fluoroscopy to visualize the uterine cavity and fallopian tubes. It evaluates tubal patency and may delineate subtle distortions in the uterine cavity by polyps or other small masses. HSG is commonly used for infertility evaluation, and may also be considered for chronic pelvic pain.

Common imaging techniques useful for evaluation of pelvic pain include ultrasound, CT, and MRI.

      • PID:  Transvaginal ultrasound or MRI may show thickened, fluid-filled Fallopian tubes.
      • Ectopic Pregnancy:  Ultrasound investigation correlated with serial quantitative hCG levels is frequently useful in the diagnosis of ectopic pregnancy.

The Large Picture of Pelvic Pain: Male Pelvic Pain

Obviously there is some overlap in the etiologies of female and male non traumatic pelvic pain, but most etiologies are different.  Although men can suffer from diverticulitis, kidney stones, urinary tract infections, and constipation, they obviously have different reproductive organs.  Male genitourinary organs, including the prostate, penis, and testicles can be the source of both acute and chronic pelvic pain.  Men typically do not suffer from cyclical pelvic pain.

Male urethritis can present with minimal to moderate, clear to whitish, discharge and dysuria.  It is associated with Chlamydia approximately 20-50% of the time. In male patients with dysuria, especially under 35 and sexually active, a chlamydial infection should be suspected.  Occasionally, the infection can travel upwards and cause epididymitis.  This often presents as unilaterally scrotal pain associated with single-sided swelling and erythema.  Exam often reveals exquisite tenderness over the epididymis on the affected side.

Testicular torsion is more common in neonates and postpubertal males but can occur at any age. The abrupt onset of severe, hemi (one half) scrotal pain is suggestive. Classic physical findings include an elevated, swollen and tender hemi scrotal and lack of cremasteric reflex (lightly stroking the inner thigh results in an involuntary rising of the scrotum on that side).  Color Doppler ultrasound is the most useful imaging technique.  It is an important diagnosis to make early as the longer the duration, the more difficult it is to save the testicle.  Surgical repair is required.

Prostatitis can be acute or chronic and represents several disorders of the prostate involving inflammation.  It can be caused by an acute or chronic bacterial infection, or from noninfectious etiologies. An acute infection can be caused by infected urine reflux into the prostate or an ascending infection from the urethra. These are treated with antibiotics, often requiring a long duration up to several months.  Noninfectious prostatitis is not as well understood and is sometimes treated with nonsteroidal anti-inflammatories (NSAIDs) or Alpha 1 blockers.

Constipation and diverticulitis present similarly as they do in females.  Likewise, kidney stones often present with flank pain which may radiate to the scrotum, along with hematuria (blood in the urine).  Bladder infections are less common in males, but will present with painful urination, increased urinary frequency, and occasionally hematuria.  Because of urethral length, it is more likely that a male urinary tract infection represents some underlying anatomic abnormality.

Red Flags

Pelvic pain can be associated with many significant, potentially life-threatening conditions.  Other conditions are associated with significant morbidity including infertility.

Certainly a positive pregnancy test associated with pelvic pain and/or bleeding should prompt evaluation for an ectopic pregnancy.

Mucopurulent cervical discharge, fevers, and/or cervical motion tenderness can all be worrisome for pelvic inflammatory disease.  Other red flags for PID include a past history of PID and sexually transmitted diseases. Statistically, sexually active females under the age of 26 are at increased risk for PID.

Risk factors for ectopic pregnancies include a previous history of ectopics and PID, and should be considered while evaluating a woman with concerning symptoms.  Age greater than 35 is another risk factor.

Male pelvic pain can be caused by multiple issues including infections of the prostate, epididymis, or testicle.  High fevers, painful urination, or urethral discharge should prompt medical attention.

Conclusion

Pelvic pain is a common condition for both males and females.  Female pelvic pain can have many causes, and a few are quite serious.  One should seek prompt medical attention for pelvic pain associated with fevers, vaginal pregnancy, if there is a chance of pregnancy, or is associated with vaginal discharge.  Painful urination or pelvic pain associated with back pain likewise requires evaluation.

Other conditions may also require further evaluation including symptoms that are recurrent but bothersome and affecting one’s daily routine.