Patient History
Left hip/groin pain X 4 months; pain down left leg to knee.
Findings
SKELETAL: No fracture or dislocations. No intramedullary lesions. Patchy heterogeneous marrow signal intensity in keeping with bone demineralization, osteopenia or osteoporosis.
PELVIS: Expansile heterogeneous intramedullary lesion with internal necrotic “cheesy-like” debris involving the left acetabular column, left iliopectineal and ilioischial lines and left ischial tuberosity which measures 8.2cm x 10cm x 11cm (AP, transverse and CC diameters, respectively).
The right hemipelvis is intact.
JOINTS: Left total hip arthroplasty. Mild osteoarthrosis of the right hip with osteophyte spurring of the acetabular rim. Widening of the right femoral head-neck junction in keeping with cam-type deformity or femoroacetabular impingement.
Moderate osteoarthrosis of the left sacroiliac joint.
ACETABULUM/LABRUM: Frayed right superior labrum without displaced labral tears or paralabral cysts.
MUSCLES/TENDONS/LIGAMENTS: Moderate reactive edema throughout the left adductor compartment.
Heterogeneous fluid and fibrotic expansion with internal septations of the left iliopsoas bursa measuring up to 7.7cm in craniocaudal length.
OTHER/SOFT TISSUE: None.
Impressions
1. Status post left total hip arthroplasty with secondary formation of an 8.2cm x 10cm x 11cm heterogeneous expansile intramedullary pseudotumor with "cheesy-like" necrotic contents in the left acetabulum, left iliopectineal and ilioischial lines representing metallosis or particulate disease or both. Histopathologically, these lesions usually demonstrate necrosis and inflammatory responses with macrophages and cytotoxic T-lymphocytes in keeping with aseptic lymphocyte dominant vasculitis associated lesion (ALVAL). No pathologic fractures.
2. Reactive stenosing tenosynovitis of the left iliopsoas bursa.
3. Moderate reactive edema of the left adductor compartment.
