[Technique of implantation of a cementless press-fit cup in revisions with severe bone defects].
OBJECTIVE
Revision of loose cups of total hip arthroplasties. Implantation and solid fixation of a cementless press-fit cup to restore painless joint function.


METHODS
Loose cups of total hip arthroplasties. Reimplantation of a prosthetic cup after removal of an infected total hip arthroplasty.


METHODS
Bone defects of the acetabulum precluding a press-fit fixation (at least three-surface fixation) of the cup. Persistent infection.


METHODS
Exposure of the acetabulum using a standard approach. Removal of the loose cup. Cleaning of the ground with a spoon. Reaming of a new, deeper center of rotation in the acetabulum using a small reamer. Stepwise reaming of the acetabulum using increasing reamer sizes without pressure until sufficient bone contact at the rim is reached (at least three-surface fixation). Hammering in of a thin-walled cementless press-fit cup (e.g., AllofitStrade mark) of the next size as compared to the reamer chosen last to reach a 4-mm press-fit fixation. Additional screwing in of two to three cancellous screws into the os ilium.


METHODS
Thrombosis prophylaxis, physiotherapy, gait training with partial loading of the limb at 10 kg for a period of 6 weeks. Then increased loading by 10 kg per week.


RESULTS
52 cup exchanges using an AllofitStrade mark cup were clinically and radiologically analyzed over an average period of 35.8 +/- 8.8 months (26-53 months). The Harris Hip Score increased from a preoperative value of 46.4 to 87.3 points 2 years postoperatively. Two cups showed migration and one hip dislocated. Loosening has not been observed so far.
Klinik für Endoprothetik, Allgemeine und Rheumorthopädie, Orthopädische Klinik Markgröningen, Kurt-Lindemann-Weg 10, 71706 Markgröningen. b.fink@okm.de
Bernd
B
Fink
Alexandra
A
Grossmann
D000077:Acetabulum / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D001863:Bone Screws; D005260:Female; D005500:Follow-Up Studies; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000601:surgery*; D011474:Prosthesis Design; D011475:Prosthesis Failure; D016459:Prosthesis-Related Infections / Q000601:surgery; D011859:Radiography; D012086:Reoperation