What is the diagnostic approach for trochanteric pain syndrome?

Diagnosis of Trochanteric Pain Syndrome

Trochanteric pain syndrome is primarily a clinical diagnosis based on history and physical examination, with radiographs obtained first to exclude other pathology, followed by ultrasound or MRI when imaging is needed to confirm the diagnosis or guide treatment. 1

Clinical Diagnosis

Key History Features

• Lateral hip pain that is chronic and intermittent, peaking in the fourth to sixth decades of life 2
• Pain exacerbated by stair climbing, prolonged sitting, and repetitive loading of the affected area 3
• Pain reproduced with palpation of the greater trochanter 4
• Soft tissue clicking over the greater trochanter suggests associated abductor tendon abnormalities 3

Physical Examination Findings

• Lateral hip pain with FABER test (flexion, abduction, external rotation) has a sensitivity of 0.81 and specificity of 0.82 for diagnosis 4
• Tenderness on palpation of the greater trochanter is a key diagnostic feature 4
• Patients typically have no difficulty manipulating shoes and socks, which helps differentiate from hip osteoarthritis (OR 0.06) 4
• Maximum walking distance preserved compared to hip osteoarthritis 4

Imaging Algorithm

First-Line: Radiographs

Radiographs of the pelvis and hip should be obtained first in all cases to exclude alternative diagnoses such as arthritis, fractures, or bone tumors 1, 5, 6

• Radiographs showing >2 mm surface irregularities of the greater trochanter are associated with abductor tendon abnormalities, though this finding has only 64% sensitivity and 26% specificity 1, 3
• Normal radiographs do not exclude trochanteric pain syndrome 7

Second-Line: Ultrasound or MRI

When radiographs are negative, equivocal, or nondiagnostic and extra-articular soft tissue pathology is suspected, ultrasound or MRI without IV contrast are the appropriate next imaging modalities. 1

Ultrasound

• Effectively detects trochanteric bursitis and can differentiate it from other conditions 5, 6, 3
• Useful for guiding diagnostic and therapeutic injections 1, 5
• Limitation: May be difficult to distinguish trochanteric bursitis from gluteus medius tendinosis, as these conditions frequently coexist 5, 3

MRI

• Assesses peritrochanteric structures including gluteus minimus and medius muscles, abductor tendons, and the trochanteric bursa 5, 3
• Both highly sensitive and specific for detecting soft tissue abnormalities and should generally be the first imaging technique after radiographs when cross-sectional imaging is needed 1
• Useful for examining trochanteric bursitis, abductor tendinosis or tears, and calcific tendonitis 1
• IV contrast is rarely needed 1

Diagnostic Injection

Diagnostic injection with lidocaine alone or combined with corticosteroids can confirm trochanteric pain syndrome as the source of pain and provides both diagnostic information and therapeutic benefit 1, 5, 3

• Ultrasound guidance improves injection accuracy and should be used to ensure proper placement 5, 6, 3
• Trochanteric bursal or peritendinous injections are useful in determining the cause of hip pain 1

Critical Diagnostic Pitfalls

Differentiation Challenges

• Trochanteric bursitis and gluteus medius/minimus tendinosis are difficult to distinguish and frequently coexist 5, 6, 3
• Both conditions may present with similar clinical features and require imaging for definitive differentiation 5

Special Populations

• In patients with hip prostheses, extracapsular disease associated with adverse reactions to metal debris (ARMD) can be misinterpreted as trochanteric bursitis 5, 6
• Careful evaluation is needed in this population to avoid missing prosthesis-related complications 5

Excluding Alternative Diagnoses

Physical examination and imaging help differentiate trochanteric pain syndrome from:

• Hip osteoarthritis: Difficulty with shoes/socks manipulation, reduced walking distance 4
• Femoroacetabular impingement: Different pain pattern and physical exam findings 7
• Lumbar stenosis: Referred pain pattern 7