What is the best approach to manage chronic back and hip pain, a complex ovarian cyst, and a history of mesenteric adenitis in a 15-year-old female?

Management of Chronic Back and Hip Pain with Complex Ovarian Cyst in a 15-Year-Old Female

Begin with plain radiographs (AP pelvis and lateral hip views) as the mandatory first imaging test for the chronic hip pain, followed by pelvic ultrasound to characterize the ovarian cyst, while recognizing that the history of mesenteric adenitis is likely unrelated to current symptoms. 1, 2

Immediate Diagnostic Workup for Hip and Back Pain

Initial Imaging Protocol

• Obtain AP pelvis and frog-leg lateral hip radiographs first to screen for structural hip pathology, femoroacetabular impingement, acetabular dysplasia, or early arthritis that commonly presents as chronic hip and thigh pain in adolescents 1, 2, 3
• Plain radiographs serve as the essential screening tool before any advanced imaging and may identify fractures, bone tumors, or joint abnormalities 2
• If radiographs are negative or equivocal, proceed immediately to MRI hip without IV contrast (rated 9/9 appropriateness by the American College of Radiology), which detects soft tissue pathology, labral tears, early inflammatory changes, occult fractures, and nerve compression 1, 2, 3

Critical Red Flag Assessment

• Perform joint examination specifically looking for effusion, warmth, or erythema that would suggest hemarthrosis or septic arthritis—both life-threatening if missed 1
• Obtain complete blood count with coagulation studies (PT, PTT, bleeding time, von Willebrand panel) before any invasive procedures, as the combination of joint pain in an adolescent female warrants evaluation for bleeding disorders 1
• Check inflammatory markers (ESR, CRP) and consider autoimmune serology (ANA, anti-dsDNA, rheumatoid factor) if systemic symptoms present, as SLE commonly affects reproductive-age females with both polyarthritis and gynecologic symptoms 1

Hip-Specific Clinical Examination

• Test hip range of motion with the FADIR test (flexion-adduction-internal rotation)—a positive test suggests femoroacetabular impingement syndrome with possible labral pathology 3
• Assess for mechanical symptoms such as catching, locking, or giving way, which strongly indicate intra-articular hip pathology 3
• Remember that chronic hip pathology frequently presents as thigh or back pain rather than isolated groin pain in adolescents 3

Management of Complex Ovarian Cyst

Ovarian Cyst Evaluation

• Obtain pelvic ultrasound to characterize the cyst size, complexity, and features to determine malignancy risk and guide management 1, 4
• In premenopausal adolescents, the risk of malignancy is approximately 1:1,000, with most cysts being benign functional cysts 4
• Simple cysts <5 cm typically resolve spontaneously without intervention, while cysts ≥5 cm are less likely to resolve and require closer monitoring 4

Symptoms Requiring Urgent Evaluation

• Assess for ovarian torsion if sudden onset severe colicky unilateral pain radiating from groin to loin with nausea/vomiting—this is most common with dermoid cysts 4
• Functional cysts can cause irregular vaginal bleeding or menorrhagia, which may explain any menstrual disturbances 4
• Laparoscopic management is safe and effective for large benign ovarian cysts in adolescents when properly selected 5

Addressing Mesenteric Adenitis History

Clinical Relevance

• The history of mesenteric adenitis is likely unrelated to current chronic symptoms, as mesenteric adenitis is typically an acute, self-limited condition associated with viral or bacterial infections 6, 7
• Mesenteric cysts are extremely rare (1 per 100,000-250,000 admissions) and usually present with acute abdomen, non-specific abdominal features, or as incidental findings—not chronic pain 6
• However, if pelvic ultrasound identifies a cystic mass that appears separate from the ovaries, consider mesenteric cyst in the differential diagnosis, as these can be misinterpreted as ovarian cysts in female adolescents 8, 7

Diagnostic Algorithm Summary

Step 1: Obtain AP pelvis and lateral hip radiographs immediately 1, 2, 3

Step 2: Perform pelvic ultrasound to characterize ovarian cyst 1, 4

Step 3: Check CBC with coagulation studies and inflammatory markers 1

Step 4: If hip radiographs negative/equivocal, proceed to MRI hip without IV contrast 1, 2, 3

Step 5: Consider image-guided intra-articular hip injection (rated 8/9 appropriateness) if diagnosis remains unclear after imaging to confirm hip joint as pain source 2, 3

Step 6: Refer to gynecology for cyst management if ≥5 cm or symptomatic 4

Step 7: Refer to rheumatology if inflammatory arthropathy suspected based on initial workup 1

Critical Pitfalls to Avoid

• Never proceed directly to advanced imaging without obtaining plain radiographs first—this violates established imaging algorithms and may miss obvious pathology 1, 2
• Do not assume the ovarian cyst explains all symptoms—hip pathology commonly refers pain to the back and thigh in adolescents 3
• Avoid delaying MRI if pain persists or worsens, as occult femoral neck fractures can present with normal initial radiographs and require urgent surgical intervention 2
• Do not order CT, PET, or bone scan for this clinical scenario (rated 1/9 appropriateness)—these expose patients to unnecessary radiation and provide inferior diagnostic information compared to MRI 2
• Never perform invasive procedures before obtaining coagulation studies in an adolescent with joint pain 1