Case Presentation: Patient is a 20-year-old female with no significant past medical history who presented with groin pain and fever. She is a college athlete who runs ten miles daily. Two weeks prior to presentation, the patient had traveled to Canada for vacation. Recent activity included zip-lining during which she wore groin harness. The groin pain worsened until she was unable to ambulate. She described the pain as a pulling sensation in her groin, exacerbated by walking. Patient denied trauma, lesions, abrasions to the area or other injuries. Imaging of the abdomen and pelvis revealed free fluid in the pelvis and bilateral ovarian anechoic follicles. Pelvic MRI revealed a 42mm complex abscess, septic joint with acute osteomyelitis and extensive adjacent myositis/cellulitis. Fluid and blood cultures resulted positive for Methicillin Sensitive Staphylococcus Aureus (MSSA). Orthopedic Surgery and Obstetrics and Gynecology services were both consulted; no intervention was indicated. Endocarditis was ruled out with Transesophageal Echocardiogram (TEE). Ultimately, no additional infectious source was identified. Patient was prescribed a six week course of intravenous nafcillin and was discharged home with scheduled outpatient follow-up.

Discussion: Septic arthritis of the pubic symphysis, so called osteomyelitis pubis is a rare infection involving the pubic symphysis and its joint. It accounts for less than 1% of cases of osteomyelitis. Literature review suggests osteomyelitis pubis as a progression of osteitis pubis. The pathogenesis is attributed to microtrauma with repetitive movement during sports that makes it susceptible to seeding of S. aureus. MRI is the most reliable method of detection. A large case series determined that patients diagnosed early in their course of osteitis pubis experienced return to play faster with early conservative management. Initial treatment of the condition is based on conservative measures including rest, non-steroidal anti-inflammatory drugs, physical therapy and compression shorts. Reports show active rehabilitation programs improves the coordination and strength of muscles that act on the pelvis. Therefore, conservative therapy is typically the first step in the treatment of osteitis pubis, as aggressive early treatment can minimize risk of progression to osteomyelitis pubis.

Conclusions: Osteomyelitis pubis should be suspected in a patient with acute onset of pubic symphysis pain, fever and symptoms of systemic involvement. The standard treatment is a prolonged course of intravenous and oral antibiotics and abscess drainage if possible. Awareness and early recognition of osteitis pubis can prevent disease progression and unnecessary invasive treatment.

IMAGE 1: Image 1: 42 mm rim enhancing loculated collection in the anterior pelvis abutting the pubic symphysis