Osteitis pubis is a clinical syndrome characterized by localized tenderness over the symphysis pubis, pain radiating into the inner thigh, and a waddling gait. First described as a complication to suprapubic surgery, contemporary thinking ascribes the symptoms associated with osteitis pubis to a noninfectious inflammation of the pubic symphysis (Fig. 119.1). Patients suffering from osteitis pubis exhibit pathognomonic radiographic and sonographic changes consisting of erosion, sclerosis, and widening of the symphysis pubis (Fig. 119.2). Osteitis pubis has a peak incidence of occurrence between the second and fourth decades affecting females much more commonly than males.

Inciting factors associated with osteitis pubis are listed in Table 119.1. Most common among these are suprapubic surgeries, athletic injuries (especially associated with the cutting and kicking maneuvers seen in Australian football), pregnancy, repetitive stress injuries, and blunt trauma to the symphysis pubis. A pain syndrome that presents with identical symptoms to osteitis pubis is occasionally seen in patients who suffer from rheumatoid arthritis and ankylosing spondylitis but without the characteristic radiographic changes of osteitis pubis.

On physical examination, the patient suffering from osteitis pubis will exhibit exquisite point tenderness over the symphysis pubis. Tenderness to palpation of the anterior pelvis is often present with the elicited pain sometimes radiating into the internal thigh (Fig 119.3). On ambulation, a waddling gait is often identified as the patient attempts to avoid any movement of the inflamed pubic symphysis. This dysfunctional gait may cause a secondary bursitis and tendinitis around the hip and groin, which may serve to confuse the clinical picture and further increase the patient’s pain and disability.

Plain radiographs are indicated in all patients who present with pain thought to be emanating from the symphysis pubis to rule out occult bony pathology and tumor (Fig. 119.4). Based on the patient’s clinical presentation, additional testing may be indicated, including complete blood cell count, prostate-specific antigen, sedimentation rate, and antinuclear antibody testing. Magnetic resonance imaging of the pelvis is indicated if occult mass or tumor is suggested as well as to confirm the diagnosis. Radionuclide bone scanning may be useful in ruling out stress fractures not seen on plain radiographs as well as to confirm the diagnosis (Fig. 119.5). Ultrasound-guided injection of the pubis symphysis serves as both a diagnostic and a therapeutic maneuver.

The symphysis pubis is a nonsynovial amphiarthrodial joint that provides articulation between the two pubic bones. The avascular interpubic fibroelastic cartilage connects the two opposing articular surfaces of the pubic bones (Fig. 119.6). The interpubic fibroelastic cartilage is wider anteriorly, narrowing toward the back of the joint space. This asymmetrical shape gives the joint space and its adjacent pubic bodies their characteristic heart-shaped appearance on transverse ultrasound scan (see below). These articular surfaces have thin layers of hyaline articular cartilage that are subject to damage or inflammation. In health, the joint can be moved forward and backward ˜2 mm with a minimal amount of rotation. The range of motion of the joint increases dramatically in women during childbirth. The joint is relatively avascular, which accounts for the difficulty in treating joint space infections of the symphysis pubis. The joint is strengthened by a variety of
ligaments, including the superior pubic ligament, which connects the top of the joint, and the arcuate ligament, which strengthens the joint from below. These ligaments are subject to disruption from blunt trauma to the pelvis, including seatbelt injuries.