What could be causing pain on the outer hip when sitting in an adult with no significant medical history?

Lateral Hip Pain While Sitting: Diagnosis and Management

The most likely diagnosis is greater trochanteric pain syndrome (GTPS), which includes gluteus medius tendinopathy, trochanteric bursitis, and iliotibial band friction—this is the predominant cause of lateral hip pain in adults and is characteristically aggravated by prolonged sitting and direct pressure over the lateral hip. 1, 2

Clinical Presentation and Key Diagnostic Features

Lateral hip pain while sitting is pathognomonic for GTPS because sitting places direct pressure on the greater trochanter and associated soft tissues. 1, 2

Distinguishing GTPS from Other Hip Pathology

• Pain location is critical: Lateral hip pain points to GTPS, while anterior hip/groin pain suggests intra-articular pathology (labral tears, FAI syndrome, or osteoarthritis). 1
• GTPS presents with tenderness to palpation directly over the greater trochanter, which is absent in intra-articular hip disease. 1, 2
• Pain with sitting, lying on the affected side, and climbing stairs strongly supports GTPS over intra-articular causes. 2
• The FADIR test (flexion-adduction-internal rotation) should be negative in GTPS—a negative FADIR helps rule out intra-articular hip disease. 3

Diagnostic Workup Algorithm

Step 1: Targeted Physical Examination

• Palpate the greater trochanter for point tenderness—this is the hallmark finding of GTPS. 1, 2
• Perform the FADIR test: If negative, this effectively rules out intra-articular hip pathology (FAI syndrome, labral tears, osteoarthritis). 3
• Assess for pain with resisted hip abduction and external rotation—weakness or pain suggests gluteus medius tendinopathy. 1
• Examine the lumbar spine and sacroiliac joints, as referred pain can mimic lateral hip pain. 3

Step 2: Initial Imaging

• Start with AP pelvis and lateral hip radiographs to exclude alternative diagnoses such as hip osteoarthritis, fractures, or dysplasia. 3
• Imaging should always be combined with symptoms and clinical signs—never use imaging in isolation. 3
• Radiographs are typically normal in GTPS, which is a clinical diagnosis. 2

Step 3: Advanced Imaging (If Diagnosis Remains Unclear)

• MRI or ultrasound can visualize gluteus medius tendon tears, bursitis, or iliotibial band pathology if conservative treatment fails or surgical intervention is considered. 1
• The American College of Radiology rates MRI hip without contrast as appropriate (rating 7-9) for chronic hip pain when diagnosis is uncertain. 3

Critical Diagnostic Pitfalls to Avoid

• Do not assume all hip pain is intra-articular—lateral hip pain is almost never from inside the joint. 1
• Failing to palpate the greater trochanter leads to missed GTPS diagnoses and unnecessary advanced imaging. 1, 2
• Referred pain from the lumbar spine or sacroiliac joint can present as lateral hip pain—always examine these structures. 3
• Labral and chondral pathology are common incidental findings on imaging in asymptomatic people—do not over-interpret imaging without correlating to clinical findings. 3

Initial Management Approach

• Physical therapy targeting hip abductor strengthening and iliotibial band stretching is first-line treatment for GTPS. 3, 1
• NSAIDs or acetaminophen provide symptomatic relief. 3
• Local corticosteroid injection into the trochanteric bursa offers both diagnostic confirmation and therapeutic benefit if conservative measures fail after 4-6 weeks. 3, 2
• Avoid prolonged sitting and direct pressure on the lateral hip—use cushioning or modify sitting positions. 2

When to Consider Alternative Diagnoses

• If pain is anterior (groin) rather than lateral, consider intra-articular pathology: FAI syndrome in younger active adults, or osteoarthritis in older adults. 3, 1
• If the FADIR test is positive, obtain AP pelvis and lateral femoral head-neck radiographs, and consider MRI/MRA for labral or cartilage evaluation. 3
• If pain is posterior (buttock), consider lumbar radiculopathy, deep gluteal syndrome, or hamstring tendinopathy. 1