Evaluation and Management of Groin Pain After Hip Arthroplasty

Clinical Assessment

The American College of Radiology recommends that radiographic signs of acetabular component loosening include progressive lucencies >2mm at the bone-prosthesis interface and superior migration of the bipolar component 3, 4
Acetabular-side failure is a significant mechanical problem, with polyethylene wear leading to osteolysis, which appears as expansile well-defined lucent lesions on imaging 4, 5

The American College of Radiology suggests that night pain or rest pain strongly suggests infection, while mechanical pain is predominantly weight-bearing related 6
Image-guided hip aspiration for synovial fluid analysis is the most useful test for confirming or excluding infection 6
Combined WBC scan and sulfur colloid scan has 88-100% specificity for periprosthetic hip infection 3, 7

Abductor tendon tears, tendonopathies, and trochanteric bursitis cause lateral hip pain, with MRI detecting 21 soft tissue abnormalities including 12 tendonopathies and 2 tendon tears 3, 6
Trochanteric surface irregularities >2mm on radiographs indicate abductor tendon abnormalities 8

The American College of Radiology recommends obtaining AP pelvis and lateral hip radiographs comparing to prior postoperative films to assess for component migration, progressive lucencies, osteolysis, or periprosthetic fracture 6, 8
CT with metal artifact reduction is superior for quantifying osteolysis, assessing bone-implant interface, and detecting component loosening (sensitivity 84.85% vs 33.3-51.5% for radiographs) 4, 6
MRI with metal artifact reduction sequences is superior for soft tissue evaluation, including tendon tears, bursitis, and detecting osteolysis (95.4% sensitivity) 4, 5, 6