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[Clinical analysis of revision after primary hip replacement in the early stage].

OBJECTIVES
To analyze the reason of revisions no more than 5 years after primary hip replacement, and to discuss the methods how to prevent and manage.


METHODS
Retrospectively review 11 cases with revision no more than 5 years after primary total hip replacement from January 2002 to June 2007. The reasons for revision were as follows: 2 cases were recurrent dislocation due to malposition of acetabular prosthesis; 5 cases were loosening of acetabular prosthesis; 1 case was abrasion of the native acetabulum by bipolar femoral head; 2 cases were periprosthetic femoral fractures and 1 case was periprosthetic infection. The average follow-up time was 36 months. Each patient was assessed according to Harris hip score. The revision procedures including liner only, acetabular prosthesis only, or both acetabular prosthesis and femoral prosthesis depending on the reasons for revision, two-stage revision was performed on 1 case with periprosthetic infection.


RESULTS
The average of Harris hip score was increased from 46 (28 to 62) preoperatively to 86 (75 to 96) at follow up. The complication occurred in 2 cases: one was postoperative haematoma formation who was performed further surgery for clearance of haematoma, another was slight instability of the hip joint who was accepted skin traction for 3 weeks.


CONCLUSIONS
The main reason for revision after primary total hip replacement is related to uncorrected insert of acetabular prosthesis. Improving surgical technique of insert of acetabular prosthesis is important in primary total hip replacement.