Abstract
A prospective consecutive series of uncemented, hydroxyapatite coated primary hip replacements utilizing two different types of alumina ceramic inserts and alumina ceramic heads is reported. Clinical and radiological results together with complications and reoperations are detailed.
193 hips followed up to 39 months using the Secur fit cup with ABC liner (Stryker). 40 hips using the Trident AD shell with the Trident titanium wrapped liner are reported up to 18 months.
Clinical scores (Harris and Postel Merle D’Aubigne) are similar to metal polyethylene at early review. SF 12 physical scores improved post operation. 100% bony ingrowth was seen radiologically (Engh and ARA scores).
Liner rim surface chips on insertion were seen in 1.4% of the ABC liners and none occurred after the 20th hip. No chips were seen in the Trident liners. One ABC liner sustained extensive surface rim chips in a heavy fall at 24 months. This is the first report of such a liner fracture. One Secur fit ABC cup was revised for recurrent subluxation.
The importance of early revision of ceramic fractures and the re use of shells is discussed. The addition of a titanium sandwich wrap to the ceramic liner is likely to eliminate the early chips.
The abstracts were prepared by Nico Verdonschot. Correspondence should be addressed to him at Orthopaedic Research Laboratory, University Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands.
