What is the likely diagnosis for a young to middle-aged adult with no previous hip conditions or surgeries, presenting with right lateral hip pain and a positive Trendelenburg gait after starting jogging, with possible differential diagnoses including greater trochanteric pain syndrome (GTPS), labral tear, hamstring strain, sacroiliac joint dysfunction, or femoral acetabular impingement (FAI)?

Diagnostic Assessment for Right Lateral Hip Pain with Trendelenburg Gait

Greater trochanteric pain syndrome (GTPS) is the most likely diagnosis in this patient presenting with lateral hip pain and Trendelenburg gait after starting jogging. The combination of lateral hip pain location and Trendelenburg gait strongly suggests gluteus medius/minimus tendinopathy or tear, which is the primary pathology underlying GTPS 1, 2, 3.

Clinical Reasoning

Why GTPS is Most Likely

• Lateral hip pain is the hallmark of GTPS, distinguishing it from intra-articular hip pathology (FAI, labral tears) which typically presents with anterior groin pain 4, 3
• Trendelenburg gait specifically indicates abductor tendon dysfunction (gluteus medius/minimus), which is the core pathology in GTPS 1, 2
• New-onset jogging is a classic precipitant for GTPS, as repetitive loading can trigger tendinopathy in previously sedentary individuals 2, 5
• Point tenderness over the posterolateral greater trochanter on examination would confirm this diagnosis 5, 6

Why Other Diagnoses Are Less Likely

• FAI syndrome and labral tears present with anterior groin pain as the primary symptom, not lateral hip pain 4. The absence of groin pain helps exclude these diagnoses 4
• Hamstring strain would cause posterior thigh/buttock pain with pain on resisted knee flexion, not lateral hip pain with Trendelenburg gait 3
• Sacroiliac joint dysfunction presents with posterior hip/buttock pain and would not cause Trendelenburg gait 3

Diagnostic Workup Algorithm

Initial Imaging

• Obtain AP pelvis and lateral hip radiographs first to exclude alternative diagnoses including osteoarthritis, fractures, or dysplasia 1, 7
• Radiographs showing greater trochanter irregularities have poor diagnostic accuracy (only 24.7% positive predictive value), so negative radiographs do not rule out GTPS 1

Advanced Imaging Indications

• Order MRI of the hip without contrast if Trendelenburg gait persists or symptoms are refractory to initial conservative treatment to evaluate for abductor tendon tears (gluteus medius and minimus) 1
• MRI is particularly useful when surgical intervention is being considered 1, 6
• Ultrasound is an excellent first-line alternative due to availability, low cost, dynamic assessment capability, and ability to guide injections 6

Clinical Examination Priorities

• Assess for point tenderness over the posterolateral greater trochanter, which is the key physical finding 5, 6
• Perform FADIR test (flexion-adduction-internal rotation) - a negative test helps rule out intra-articular hip pathology, though its clinical utility is limited 4
• Screen the lumbar spine and pelvis to exclude referred pain, as lumbar radicular pain can mimic lateral hip pain 4, 6

Critical Diagnostic Pitfalls

• Never diagnose hip-related pain based on imaging alone - imaging has only small to moderate shifts in post-test probability and must be combined with symptoms and clinical signs 4, 7
• Do not assume lateral hip pain is always GTPS - perform comprehensive examination including lumbar spine screening, as radicular pain and hip osteoarthritis can present identically 6
• Incidental imaging findings are common in asymptomatic individuals and should be managed with appropriate clinical sensitivity 4
• Beware that multiple hip conditions can coexist - labral and chondral conditions often coexist with FAI syndrome 4