Diagnostic Approach to Deep Right Pelvic Pain with Hip Flexion Aggravation

Initial Imaging Strategy

• The American College of Radiology recommends beginning with plain radiographs of the pelvis and right hip to screen for osseous abnormalities, followed by MRI if radiographs are negative or nondiagnostic, as this presentation most likely represents iliopsoas pathology or hip joint pathology requiring soft tissue evaluation 1, 2
• Plain radiographs serve as an excellent screening tool and guide selection of additional imaging, even when normal 1
• Pain with hip flexion and difficulty donning pants strongly suggests iliopsoas involvement or anterior hip pathology 2

Imaging Modalities

• MRI is highly sensitive and specific for detecting soft tissue abnormalities around the hip and pelvis, and should be proceeded to directly without contrast if radiographs are negative or nondiagnostic 2
• MRI can identify iliopsoas bursitis or tendinosis, subiliacus bursitis, athletic pubalgia, abductor tendinosis or tears, hamstring injuries, labral tears, occult fractures or stress injuries, and soft tissue masses or tumors 1, 2
• Ultrasound can be considered if MRI is unavailable or for targeted evaluation of suspected iliopsoas pathology, but is operator-dependent and less comprehensive than MRI 2

Critical Differential Diagnoses to Consider

• Iliopsoas bursitis/tendinosis is a classic presentation with hip flexion pain and anterior/medial hip tenderness 2
• Hip joint pathology, such as labral tear, early arthritis, or femoroacetabular impingement, can also cause hip flexion pain 1, 2
• Abductor tendon pathology and pelvic floor myofascial pain with referred symptoms are other potential causes of hip flexion pain 2, 3

Physical Examination Findings to Document

• The exact location of point tenderness, such as anterior groin suggesting iliopsoas pathology, is important to document 1, 2
• Hip range of motion, particularly internal rotation, can reproduce pain in intra-articular pathology 6
• The FABER test (Flexion, ABduction, External Rotation) can suggest hip joint pathology 1
• Resisted hip flexion can reproduce pain in iliopsoas pathology 2

Treatment Considerations After Diagnosis

• Manual physical therapy targeting pelvic floor and hip musculature can be effective for iliopsoas pathology with a myofascial component 3
• NSAIDs and acetaminophen can be used for symptom management in hip joint pathology 6
• Surgical consultation may be necessary if conservative measures fail for hip joint pathology 6