Osteitis pubis: A rare cause of suprapubic pain

Abstract

Osteitis pubis is a noninfectious inflammatory condition affecting the pubic symphysis. First described in a series of patients undergoing urologic procedures, it is an uncommon cause of lower abdominal and suprapubic pain. However, this condition can cause significant morbidity in patients affected, often requiring lengthy recovery periods. Given its rarity, the diagnosis and management is challenging, as many urologists are unfamiliar with the condition and may ascribe the constellation of symptoms as expected side effects from a recent surgical procedure. This review describes the urologic considerations for osteitis pubis, its potential etiologies, and clinical findings, and identifies treatment strategies for this potentially debilitating condition.

Osteitis pubis was first noted in the English literature by urologist Edwin Beer when he described a series of patients with a specific set of symptoms following suprapubic surgery.¹ Given this first description in a group of patients undergoing urologic surgery, it is not surprising that osteitis pubis has been noted following many different urologic procedures over the years; any pelvic surgery has the potential to cause osteitis pubis. In the general surgery literature, herniorrhaphy has been linked with this condition,² and in the field of obstetrics and gynecology, pregnancy has been associated in both the ante- and postpartum periods.^3-5 In the urologic literature, it has been described after a myriad of procedures, including transurethral resection of the prostate, prostate cryotherapy, photovaporization of the prostate, periurethral collagen injection, transrectal needle biopsy of the prostate, high-intensity focused ultrasound treatment of the prostate, prostatectomy, and cystectomy.^6-10 Classically, in the urologic literature, the procedures most frequently cited as risk factors are the traditional techniques for stress urinary incontinence, most commonly the Marshall-Marchetti-Krantz (MMK) urethropexy. The MMK procedure involves placing sutures directly into the pelvic bone periosteum of the pubic rami. Reviews of the MMK procedure have cited rates of osteitis pubis in up to 2.5% of patients, with a range of 0.7% to 2.5%.^11-14 Although no large studies have been performed to better determine this rate in surgical patients, on average, in the urologic literature, osteitis pubis occurs in slightly fewer than 1 in 100 patients undergoing urologic procedures.

Pathophysiology and Etiology

Several theories have been proposed as etiologies for the development of osteitis pubis, such as trauma, low-grade infection, and venous congestion. Despite these notions, at present, there is currently an incomplete understanding of the true cause of this condition; the cause may be multifactorial.

Trauma as the cause for osteitis pubis was the original theory put forth by Beer in the 1920s. It makes intuitive sense that trauma to the pubic symphysis can lead to an inflammatory process that can involve the symphysis pubis. Due to the placement of sutures in the periosteum, as with MMK urethropexy, this represents a local insult to the bone itself. Additionally, osteitis pubis is seen in athletes with groin pain, supporting the theory that injury is a potential cause. Prevalence rates in athletes are varied; it is present in 10% to 80% of competitors complaining of groin and or suprapubic pain. Microtears and injury to the pelvic girdle have been implicated in certain sports associated with the condition due to rapid acceleration or deceleration, running, kicking, and prompt change of direction. Athletic activities such as soccer, fencing, American football, ice hockey, rugby, and cricket are commonly cited examples.¹⁵ However, several researchers have attempted to recreate traumatic osteitis pubis in animal models with mixed results. One early example was a failed attempt by Beneventi and Spellman¹⁶ to induce osteitis pubis in dogs through infection and various insults on the pubic symphysis, including opening the bladder to allow urine into the space of Retzius, and cartilage excision.

Limited histologic evaluation of osteitis pubis has been performed, but the few studies done support inflammation as the core etiologic issue.

Low-grade infection is another theory that has been proposed as a cause of osteitis pubis, especially in postsurgical patients. In one series of osteitis pubis after MMK, seven patients ultimately failed conservative management and required surgery. Bone cultures from the surgical procedure were sampled and demonstrated infection in five patients (71%).¹² However, another series, in which bone material was collected for culture, found no organisms but did find infected urine in 44% of these patients.¹⁷

Various theories regarding vascular obstruction, thrombosis, or otherwise impaired venous flow have also been proposed. Steinbach and colleagues,¹⁸ in the 1950s, felt that an obstruction of the prostatic plexus in men was a possible cause. Because this venous plexus drains some of the posterior veins of the pubic symphysis, obstruction could cause hyperemia with resultant bone demineralization. Due to the close association of the veins of the urinary tract and those that drain the pubic symphysis, and an anatomic lack of valves in these vessels, infection-induced urinary stasis has also been proposed as an inciting factor for venous congestion.¹⁷

The classic gait disturbance described in osteitis pubis is a “waddling” gait, a form of an antalgic gait.

Limited histologic evaluation of osteitis pubis has been performed, but the few studies done support inflammation as the core etiologic issue. From a Mayo Clinic (Rochester, MN) series of 45 patients diagnosed with osteitis pubis, 7 had tissue available for review. All seven samples showed an inflammatory exudate composed of plasma cells and lymphocytes, with evidence of marrow fibrosis and thin layers of new bone in several samples.¹⁷

Clinical Features, Presentation, and Work-up

Presentation of patients with osteitis pubis can be broad and vague. Patients can present with generalized lower abdominal pain, which has a large differential. Typically, pain is localized to the lower abdomen and groin, with radiation to the inner thigh adductor muscles, and often is associated with gait disturbances. Discomfort is usually aggravated by any activity that increases pressure on the pelvic girdle, including walking, coughing, sneezing, lying on one side, and walking up or down stairs. The pain itself can be sharp during those activities, but commonly is described as an aching, throbbing, dull pain on cessation of the activity. The classic gait disturbance described in osteitis pubis is a “waddling” gait, a form of an antalgic gait. Given that the proximal thigh adductor muscle attachments are to the inferior pubic ramus just lateral to the pubic symphysis, it is not surprising that the aforementioned gait disturbances may develop. Incidentally, the thigh adductors are a group of muscles that urologists are acutely familiar with, given their innervation by the obturator nerve—an important landmark during pelvic lymph node dissection.

For all patients presenting with possible osteitis pubis, a thorough history and physical examination should be performed, with focus on any recent or remote urologic or pelvic surgical procedures, or any local trauma or repetitive injury to the area in question. On average, symptoms of osteitis pubis appear approximately 6 to 8 weeks after an offending surgical procedure, but the interval can be shorter or longer.¹⁷ Focal physical examination findings can include point tenderness over the pubic symphysis or lateral to the pubic symphysis. Generalized symptoms can include malaise and occasional low-grade fever. Given the overlap of symptoms, groin hernias should be ruled out. In men, strong consideration should be given for a prostate examination to rule out prostatitis; in women, a thorough pelvic examination to rule out other diagnoses such as pelvic inflammatory disease should be performed. Specific physical examination tests that may elicit the classic pain include the “pubic spring” test and “lateral compression” test. The spring test is performed by placing simultaneous downward pressure on both pubic rami; if pain is reproduced at the pubic symphysis this is considered a positive sign. This test can also be performed on either side to see if the pain is localized. Additionally, a positive lateral compression test result occurs when the patient is in the lateral decubitus position and downward pressure on the superior iliac wing produces pain at the pubic symphysis.¹⁹ Other tests that may reproduce symptoms include the FABER (flexion, abduction, and external rotation) test, which is classically used for hip or sacroiliac joint pathology, but will also reproduce pain at the pubic symphysis due to the leg being placed in an abducted position. And the “adductor squeeze” test, in which the patient squeezes the practitioner’s fist that is placed between the patient’s knees, can elicit classic osteitis pubis discomfort. Orthopedic consultation should also be considered if the diagnosis is not certain. These tests and findings are summarized in Table 1.

Table 1.

Physical Examination Tests and Positive Findings Suggestive of Osteitis Pubis

Test Name	Technique	Positive Finding
Pubic spring test	Examiner places simultaneous downward pressure on pubic rami with hands	Pain is reproduced at the pubic symphysisa
Lateral compression test	Patient is in lateral decubitus position	Pain is reproduced at
	Examiner places downward pressure on the superior iliac wing	the pubic symphysis
FABER (flexion, abduction,	Patient is supine	Pain is reproduced at
and external rotation)	Leg is flexed and the thigh abducted and externally rotated simultaneously (maneuver is performed 1 leg at a time)	the pubic symphysis
Adductor squeeze test	Patient is supine	Pain is reproduced at
	Examiner places a fist between patient's knees, and patient is asked to compress the examiner's fist	the pubic symphysis

^aThe test can also be performed on either side of pubic rami to see if pain lateralizes.

On average, symptoms of osteitis pubis appear approximately 6 to 8 weeks after an offending surgical procedure …

Given the overlap in symptoms, osteomyelitis of the pubic symphysis should always be considered high in the differential, especially in the urologic patient that has undergone a surgical procedure.

Given the overlap in symptoms, osteomyelitis of the pubic symphysis should always be considered high in the differential, especially in the urologic patient that has undergone a surgical procedure. Although there is symptom overlap, patients with osteomyelitis typically appear more toxic, with higher fevers, and have laboratory evaluation indicative of significant infection.²⁰ Although noninfectious osteitis pubis is more insidious in nature, osteomyelitis typically has more acute presentation.

Osteitis pubis is typically a clinical or radiographic diagnosis. Laboratory analysis is not required in most cases. In the setting of a febrile and sick-appearing patient, blood cultures and a complete blood count should be obtained, and consideration for inpatient admission should be given until stabilization has been demonstrated. If blood culture results are negative, aspiration and culture of the joint space may be beneficial to isolate any organisms. Because of the suggested association with positive urine culture and the higher rate of bacteriuria and urinary tract infection, a clean-catch urine culture can also be obtained. In some cases, erythrocyte sedimentation rate may also be elevated, though it is a nonspecific finding.

Modalities include conventional radiographs, magnetic resonance imaging, scintigraphy, and symphysography.

Imaging

Several radiologic modalities can be utilized to diagnose or exclude osteitis pubis. Although some of these tests may be more appropriate for an orthopedic physician to order, urologist awareness of the imaging modalities and classic findings can be useful in the multidisciplinary management of this condition. Modalities include conventional radiographs, magnetic resonance imaging (MRI), scintigraphy, and symphysography. If present, findings on conventional radiograph include irregularities, sclerosis, and osteophytes on the articular surfaces, and can also demonstrate widening of the pubic symphysis joint space (Figure 1). Findings may not be present in the early stages on plain radiograph alone and a negative radiographic result does not rule out osteitis pubis. Findings in scintigraphy include focal accumulation of the injected radionuclide at or around the pubic symphysis on delayed scan images. Symphysography involves direct injection of nonionic contrast directly into the symphyseal joint. This modality has the benefit of showing provoked symptoms with injection, helping to confirm the diagnosis, as well as providing a method for temporary relief with the ability to inject steroids and local anesthetic.²¹ Both scintigraphy and symphysography are invasive imaging procedures and, for the most part, should not be considered first line. MRI may be the best imaging modality to assess for osteitis pubis because of its tissue inflammatory component, which is often easily demonstrated on MRI (Figure 2). MRI has the ability to help distinguish fine tissue details to help differentiate osteitis pubis from osteomyelitis. Although associated MRI findings shown in reports vary, commonly they include periarticular edema, fluid in the pubic symphyseal joint, and bone marrow edema in acute osteitis pubis lasting less than 6 months; chronic cases lasting longer than 6 months may show subchondral sclerosis, resorption, and the presence of osteophytes (Table 2).²²

Figure 1.

Conventional radiograph in a patient with pelvic pain with ambulation who was diagnosed with osteitis pubis. Note the widening of the pubic symphysis with sclerotic changes.

Figure 2.

Coronal T2-weighted 3T magnetic resonance image (MRI) of a 77-year-old man with prostate adenocarcinoma treated with primary cryotherapy followed by salvage radiation therapy, which was complicated by recurrent urethral stricture disease. His strictures were managed by chronic indwelling suprapubic tube. He presented to urology clinic with 6 months of suprapubic and leg pain. His leg pain was not present at rest, but was severe with ambulation and standing. MRI findings include edema of the symphysis and inferior pubic rami and of adjacent soft tissues. Osteitis pubis was the primary diagnosis.

Table 2.

Imaging Tests and Their Associated Findings in Osteitis Pubis

Radiographic Test	Findings Suggestive of Osteitis Pubis
Conventional radiographa	Articular joint irregularities
	• Sclerosis
	• Subchondral erosion
	• Osteophyte formation
	Widening of the symphyses (no formal width defined for a widened joint; normal joint width varies with age/sex)
Magnetic resonance imaging	Acute (<6 mo)
	• Periarticular edema
	• Fluid in the pubic symphyseal joint
	• Bone marrow edema
	Chronic (>6 mo)
	• Subchondral sclerosis
	• Resorption
	• Osteophytes
Scintigraphy	Focal accumulation of nucleotide tracer at or around pubic symphysis
	• Can be unilateral or bilateral uptake
Symphysographyb	Loss of disc morphology
	Extravasation into local bony defects
	Lymphatic/venous intravasation from hyperemia (less common)

^aFindings may take months to manifest on plain radiograph.

^bThis procedure has the benefit of being both therapeutic and diagnostic.

Treatment

Much of what we know about treatment of osteitis pubis comes from the sports medicine literature, because higher rates of osteitis pubis are seen in the athlete population. Treatment modalities range from conservative management with rest to invasive surgical interventions. Although initial attempts at conservative treatment can be performed by the urologist, if these conservative measures fail, referral to an orthopedic/sports medicine specialist can be considered for initiation of more aggressive treatment strategies. Due to the rarity of this condition, no prospective randomized controlled trials have been performed to determine the best treatment approach. A general overview of the treatment strategies is provided in Table 3.

Table 3.

Treatment Strategies for Osteitis Pubis

Treatment Strategy	Specific Interventions
Conservative/noninvasivea	Rest, minimize activities that place stress on the pelvic girdle
	Use assistive devices (eg, crutches, cane) while recovering ice/heat therapy
	Oral nonsteroidal anti-inflammatory medications physical therapy
Local/in-office proceduresb	Local joint injections
	• Corticosteroid
	• Anesthetic
	• Combined steroid with anesthetic
	Anticoagulant therapyc
	• Heparin
	• Warfarin
Surgical approachesd	Curettage
	Arthrodesis
	Wedge resection of public symphysis
	Wide resection of public symphysis

^aThese are within the scope of practice and easily initiated by the evaluating urologist.

^bReferral to an orthopedic specialist is likely beneficial.

^cData limited to a very few case reports/series.

^dReferral to an orthopedic specialist is required.

Treatment modalities range from conservative management with rest to invasive surgical interventions.

Initially, conservative treatment should be attempted, and patients should be counseled that this condition takes time to resolve. Methods included a short period of bed rest followed by progressive ambulation with or without the use of assistive devices such as crutches or a cane. Additionally, minimizing activities that place stress on the pelvic girdle can also be recommended during this phase of treatment. Local hot or cold therapy over the pubic symphysis can also be employed and oral nonsteroidal anti-inflammatory agents such as ibuprofen or cyclooxygenase-2 inhibitors can be used. Kavroudakis and colleagues²³ reported the results of their small series of nonathlete women who were treated conservatively for osteitis pubis. Of their series of 17 patients presenting with pubic symphyseal pain, 6 were ultimately diagnosed with osteomyelitis and 3 with a fracture; these 9 were excluded. The remaining patients were instructed to be on bed rest for 4 to 6 days followed by ambulation with the assistance of crutches and/or a cane. All were treated with oral anti-inflammatory medications and, at 2-month follow-up, were encouraged to start a physical therapy program to strengthen the hip and abdominal muscles while improving adductor flexibility. Five patients were completely pain free at 9 months and did not relapse, with an average of 24-month follow-up. Two other patients did continue to have pain with intense physical activity; only one completely failed conservative treatment.²³ Given the significant inflammation present, an oral glucocorticoid course with or without an appropriate taper can be attempted per physician comfort and discretion.

When conservative measures fail, local invasive therapies with corticosteroid injection with or without adjuvant anesthetic, such as bupivacaine, into the pubic symphysis can be attempted. This has been shown to be effective with rapid reduction in pain noted by most patients. As previously noted, symphysography can be both diagnostic and therapeutic if corticosteroid injection is utilized at the time of this diagnostic procedure.²¹ No studies have been performed in postoperative patients, but in a series of nine athletes, eight did not improve with conservative measures alone and proceeded to receive local corticosteroid injection therapy. Three returned to normal activity following one injection, and four required a second injection. Only one failed to improve after local joint injection.²⁴

Very limited data (only a few case reports/series) have been reported regarding the use of anticoagulants for treatment of osteitis pubis. If the venous congestion or thrombosis theory is correct, anticoagulation may help to improve symptoms and treat these patients. In one early series of three postoperative patients (1 following prostatectomy and 2 others following vaginal delivery), treatment success was only seen after heparin therapy.²⁵ In a later series of three patients with osteitis pubis following prostatectomy, conservative measures failed and clinical improvement was only seen with initiation of intravenous heparin therapy.²⁶ A more recent single case report in a patient with intractable pubic symphyseal pain following uncomplicated retropubic prostatectomy for benign prostate hyperplasia (who failed conservative management) reported successful treatment with a several-months course of warfarin, resulting in complete resolution of symptoms.²⁷

If all previous procedures fail, more invasive surgical options remain available. Given the low numbers of surgically treated cases of osteitis pubis and a paucity of data, the best surgical approach is not known. Surgical options include curettage, arthrodesis, and wedge and wide resection of the pubic symphysis. These techniques are clearly invasive and not without complications. For example, wide resection of the pubic symphysis can cause secondary issues requiring additional surgical procedures. Resection of the anterior pelvis can cause issues with pelvic instability. Moore and colleagues²⁸ reported on two patients who presented with severe debilitation from posterior pelvic instability following earlier (12-18 years earlier) resection of the pubic symphysis for treatment of osteitis pubis.²⁸ Mehin and associates,²⁹ after a small case review of 10 of their own patients and a larger review of the literature for patients undergoing surgical treatment for osteitis pubis, recommended curettage of the joint for simple cases, whereas those with osteitis pubis presenting after urologic surgery may benefit from wedge resection, especially if there are concerns for possible residual infection with curettage alone. In general, surgical intervention is withheld until conservative treatments fail, whereas in the postsurgical patient or in patients with severe symptoms, earlier surgical intervention can be suggested after appropriate patient counseling.²⁹

Surgical options include curettage, arthrodesis, and wedge and wide resection of the pubic symphysis.

Conclusions

Osteitis pubis is an incompletely understood, potentially debilitating entity regarded as a noninfectious inflammation of the pubic symphysis. Although multiple theories have been formulated, it remains unclear as to the exact etiology of this condition. Although it is seen most commonly in athletes, approximately 1 in 100 patients undergoing urologic procedures are at risk for developing this condition. The onset is typically insidious in nature, occurring 6 to 8 weeks after the index surgical procedure. The diagnosis is primarily a clinical one, with a thorough history and physical examination that includes resisted adductor testing. Osteomyelitis must be ruled out, and typically presents with a much more acute course and a toxicappearing patient. Treatment modalities include conservative measures with rest, oral nonsteroidal anti-inflammatory drugs, and physical therapy; invasive surgical techniques can be used if conservative measures fail. Osteitis pubis can be a crippling condition, but increased knowledge of its clinical course and treatment strategies can help illuminate this vague entity for patients and start them on a path toward recovery.

Main Points.

• Osteitis pubis is a noninfectious inflammatory condition affecting the pubic symphysis. It is an uncommon cause of lower abdominal and suprapubic pain, but it can cause significant morbidity in patients affected, and often requires a lengthy recovery period.

• Pain is typically localized to the lower abdomen and groin, with radiation to the inner thigh adductor muscles, and often is associated with gait disturbances. Discomfort is usually aggravated by any activity that increases pressure on the pelvic girdle, including walking, coughing, sneezing, lying on one side, and walking up or down stairs.

• For all patients presenting with possible osteitis pubis, a thorough history and physical examination should be performed, with focus on any recent or remote urologic or pelvic surgical procedures, or any local trauma or repetitive injury to the area in question.

• Osteitis pubis is typically a clinical or radiographic diagnosis. Imaging modalities include conventional radiographs, magnetic resonance imaging, scintigraphy, and symphysography.

• Conservative treatment includes rest, oral nonsteroidal anti-inflammatory drugs, and physical therapy; invasive surgical techniques can be used if conservative measures fail.