title: Trabecular metal screw implanted for avascular necrosis of the femoral head may complicate subsequent arthroplasty surgery.
abstract: A trabecular metal screw has been suggested to treat avascular osteonecrosis of the femoral head. Non-surgical management with partial weight bearing can only be selected for early stages and very small lesions. Even in such cases, it has been proven to be ineffective in 80-90 % of patients. Conversely, the results with trabecular metal implants are not always clinically satisfactory, and some patients can show emerging pain and activity limitations that could require conversion to a total hip arthroplasty. Hereby we report the results of 6 patients who underwent this implant and describe the histopathology of the bone at the femoral neck and to speculate on the causes of complications encountered during arthroplasty surgery. The necrosis was stopped in 1 case, and 5 hips showed disease progression. Two protrusions of the screw apex were observed. In one case, rupture of the greater trochanter during prosthesis implant occurred. After trabecular metal implants for avascular osteonecrosis, some patients can require conversion to a total hip arthroplasty. Two patients had an intraoperative fracture with detachment of the greater trochanter that required wiring. Complications related to implant removal can be encountered, and the orthopedic surgeon should be aware of removal techniques.
authors.affiliation: Department of Orthopaedics and Trauma Surgery, Center of Integrated Research (CIR), University Campus Bio-Medico of Rome, Rome, Italy.
authors.forename: N
authors.initials: N
authors.lastname: Papapietro
authors.forename: A
authors.initials: A
authors.lastname: Di Martino
authors.forename: G
authors.initials: G
authors.lastname: Niccoli
authors.forename: A
authors.initials: A
authors.lastname: Palumbo
authors.forename: G
authors.initials: G
authors.lastname: Salvatore
authors.forename: F
authors.initials: F
authors.lastname: Forriol
authors.forename: V
authors.initials: V
authors.lastname: Denaro
mesh_terms: D000328:Adult; D019644:Arthroplasty, Replacement, Hip; D001863:Bone Screws / Q000009:adverse effects*; D020878:Device Removal; D018450:Disease Progression; D005260:Female; D005270:Femur Head / Q000293:injuries*; D005271:Femur Head Necrosis / Q000000981:diagnostic imaging / Q000601:surgery*; D005272:Femur Neck / Q000473:pathology*; D006620:Hip Fractures / Q000209:etiology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D019919:Prosthesis Implantation / Q000009:adverse effects*; D011859:Radiography