Abstract
Purpose: We have been using the ABG cementless femoral stem since 1992 for the majority of our primary hip arthroplasty cases. This paper presents a review of our experience and results with the first 1000 ABG stems.
Method: A consecutive series of primary hip arthroplasty cases was followed prospectively beginning in 1992, with a total of 1000 cases performed before October 1996. A variety of degenerative conditions were included, and all cases were assessed using standard clinical and radiographic scoring systems, and recorded on an arthroplasty database.
Results: There were 1000 arthroplasties performed in 905 patients. Mean age at surgery was 64 years (22 to 94 years). There was a predominance of females (53%), and of right hips (58%). Mean height was 170 cms, and mean weight was 75 kgs. Diagnoses included primary or secondary osteoarthritis (93%), inflammatory arthropathy (5%), and fracture neck of femur (2%). Posterior approach was used in all but one case. A femoral fracture or stress riser was incurred in 3 cases (0.3%). A variety of acetabular components were mated with the stem, including ABG (58%), Implex one piece (20%), and ABG II no hole (20%). There were 1 deep infection, occurring acutely. There were 16 (1.6%) femoral periprosthetic fractures occurring between 2 days and 86 months after surgery, most requiring internal fixation or revision. There were 17 dislocations (1.7%) occurring between 2 weeks and 97 months after surgery. Only 1 stem has been revised for aseptic loosening, 3 for dislocation and 8 for periprosthetic fracture. At mean follow up of 60 months (24 to 108 months), average Harris Hip Score was 90/100, with 86% of patients having a good or excellent result. No additional stems were found to be loose on radiographic evaluation.
Conclusion: The design features of this anatomic, hydroxyapatite coated femoral stem provide for excellent initial stability, reliable bone ingrowth, and low intraoperative fracture rate. A small number of periprosthetic fractures occurred, most related to trauma. The proximal geometry of the implant results in low dislocation rates, despite use of the posterior approach.
The abstracts were prepared by Professor Jegan Krishnan. Correspondence should be addressed to him at the Flinders Medical Centre, Bedford Park 5047, Australia.
