ABSTRACT
Objective To investigate clinical outcomes and complications of isolated polyethylene liner exchange for revision total hip arthroplasty.Methods From April 1995 to December 2007,80 patients (93 hips) underwent revision total hip arthroplasty during which only polyethylene liner was exchanged with reservation of acetabular cup.There were 41 males and 39 females,aged from 27 to 82 years (average,53.3 years).The duration from the primary THA to the revision surgery ranged from 0.3 to 18.4 years (average,10.9 years).The reasons for liner exchange included:polyethylene wear with osteolysis (78 hips),polyethylene wear without osteolysis (5 hips),polyethylene wear with stem loosening (4 hips),recurrent dislocation (3hips),infection (1 hip),periprosthetic fracture (1 hip) and liner dislodgement (1 hip).Forty-seven liners were fixed into the old cup using cement,and 46 were fixed with the original locking mechanism.Sixty cross-linked polyethylene liners and 33 conventional polyethylene liners were used.Results All patients were followed up for 5 to 15 years (average,7 years).The average Harris hip score improved from preoperative 86.0±16.9 to 89.4±11.6 at final follow-up.Complications included dislocation (10 hips),infection (2 hips),periprosthetic fracture (1 hip) and liner dislodgement (1 hip).Ten hips underwent rerevision due to different reasons:cup exchange (5 hips),conventional polyethylene wear (2 hips),infection (2 hips) and liner dislodgement (1 hip).Using component loosening as the end point,the 10-year survival rate was 100％ in the cement fixation group and 84.8％ in the original locking group.Using rerevision as the end point,the 10-year survival rate was 90.4％ in the cement fixation group and 65.0％ in the original locking group.Conclusion Liner exchange either with cement or original locking mechanism is a safe and successful method.Highly cross-linked polyethylene has a higher wear resistance,which can reduce incidence of osteolysis and improve survival rate of prosthesis.