title: Cotton-induced pseudotumor of the femur.
abstract: Twenty-five years prior to presentation a 41-year-old man had a femoral fracture stabilized with a 4.5 mm AO/ASIF steel plate. The femur healed uneventfully and the patient was asymptomatic for the following 20 years. He then noticed a slow-growing swelling of the left thigh associated with a degree of weakness. Radiographs of the femur 25 years after fracture stabilization showed a massive expansive osteolytic process surrounded by a rim of bone. Magnetic resonance imaging (MRI) confirmed the presence of a large tumor. Since malignancy could not be excluded the patient underwent incisional biopsy. The histologic findings were nonspecific. Because of persistent symptoms the lesion was marginally excised. Intraoperatively a folded cotton sponge was found adjacent to the femur. Histopathologic investigation confirmed a foreign body reaction probably related to the retained cotton sponge. Reactive, foreign-body-induced change may mimic bone and or soft tissue malignancies.
authors.affiliation: Department of Orthopedic Surgery, Inselspital, University of Berne, Switzerland.
authors.forename: D F
authors.initials: DF
authors.lastname: Kalbermatten
authors.forename: N T
authors.initials: NT
authors.lastname: Kalbermatten
authors.forename: R
authors.initials: R
authors.lastname: Hertel
mesh_terms: D000328:Adult; D001706:Biopsy; D003937:Diagnosis, Differential; D005264:Femoral Fractures / Q000601:surgery; D005266:Femoral Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging; D005592:Fracture Fixation; D003368:Gossypium; D015745:Granuloma, Foreign-Body / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D006801:Humans; D008297:Male; D011859:Radiography; D015503:Surgical Sponges; D013848:Thigh; D013997:Time Factors