Differential Diagnosis for Hip Abductor Strain
The differential diagnosis for hip abductor strain includes trochanteric bursitis, gluteus medius/minimus tendinopathy or tears, referred pain from lumbar spine pathology, iliopsoas bursitis, hip osteoarthritis, femoroacetabular impingement, labral tears, and stress fractures.
Primary Considerations
Extra-articular Soft Tissue Pathology
The most common mimics of abductor strain involve the lateral hip soft tissues 1:
- Trochanteric bursitis - Often coexists with abductor tendinopathy and presents with lateral hip pain
- Gluteus medius/minimus tendinopathy or tears - The "rotator cuff tears of the hip" 2, particularly common in older patients and women 3
- Iliopsoas bursitis or tendinitis - Can cause anterior hip pain that may be confused with abductor pathology 1
Referred Pain Sources
Lumbar spine pathology is a critical differential 4. Patients with lower back or buttock pain radiating into the lateral leg are often misdiagnosed with sciatica when they actually have hip abductor pain syndrome. Look specifically for:
- Absence of true neurologic findings on exam
- Hip abductor muscle weakness and pain on testing
- Positive hip lag sign or failed 30-second single leg stance test 3
Intra-articular Hip Pathology
Consider these when pain is more anterior or groin-based 1:
- Hip osteoarthritis - Physical exam and radiography may be more sensitive than MRI 1
- Femoroacetabular impingement (FAI) - Requires specialized radiographic views (false profile, Dunn view) 1
- Labral tears - Often associated with impingement 1
Osseous Abnormalities
- Stress fractures - Particularly in athletes with activity-related pain
- Avascular necrosis - MRI is highly sensitive 1
- Primary bone tumors - Rare but identifiable on initial radiographs 1
Diagnostic Approach Algorithm
Step 1: Obtain plain radiographs first - This should be done in essentially all cases to screen for arthritis, fractures, and bone tumors 1.
Step 2: Perform targeted physical examination looking for:
- Hip abductor weakness (hip lag sign, 30-second single leg stance) 3
- Lateral hip tenderness over greater trochanter
- Lumbar spine examination to exclude referred pain 4
- Hip range of motion testing (reduced rotational ROM suggests intra-articular pathology)
Step 3: If radiographs are negative/equivocal and soft tissue pathology suspected, MRI is the next imaging modality 1. MRI is both highly sensitive and specific for:
- Abductor tendon tears and tendinosis 3
- Muscle fatty infiltration (predictive of repair outcomes) 3
- Trochanteric bursitis
- Labral tears and cartilage damage
Step 4: Consider ultrasound as an alternative for:
- Real-time evaluation of tendon pathology 1
- Guiding diagnostic/therapeutic injections 1
- Evaluating fluid collections 1
Critical Pitfalls to Avoid
Do not assume sciatica without neurologic findings - Hip abductor pain syndrome with muscle imbalances and myofascial trigger points is frequently misdiagnosed as radiculopathy 4.
Do not overlook age and gender patterns - Gluteal tendinopathy is more prevalent in women and increases with age 3. Older patients with lateral hip pain and weakness without arthritis should be evaluated for abductor tendon tears 2.
Do not rely solely on clinical exam - While the hip lag sign and single leg stance tests are useful 3, MRI confirmation is recommended before considering surgical intervention 2.
Recognize the three clinical presentations of abductor tears 2:
- Degenerative/traumatic tears in older patients with intractable lateral hip pain
- Relatively asymptomatic tears found incidentally during hip arthroplasty
- Avulsion or repair failure following total hip arthroplasty via anterolateral approach