Abstract
Aim and design: The Olympia prosthesis was designed to minimise the risk of cement mantle deficiency, seen with some straight stem designs. Initially six stem sizes were produced. The highly polished surface (Ra 10 nm) reduces tensile stresses and cement abrasion. The oval cross-section allows a metaphyseal rotation lock. The natural anteversion is cement mantle friendly. The absence of corners reduces the stress risers and the anatomic shape accommodates the abductor approach and MIS. A size 0 has been added to the range as have lateralised options.
Methods: The first 120 stems in 111 consecutive patients were studied prospectively and reviewed clinically and radiographically by an independent observer. All operations were carried out by the senior author (LJT) with the same team. Rigorous attention to detail was given to femoral preparation and cement technique.
Clinical Results: At a mean follow up 10 years 8 months, 92% of the patients had a Harris Hip score over 80. 97% of outcomes were classified as excellent or good on the Oxford Hip Score. At review the survival was 99.2% (one patient has been revised for non-union of a Vancouver type C peri-prosthetic fracture).
Radiographic Results: Radiographically no stems showed more than 5° varus/valgus angulation (no centraliser was used). In the lateral projection 76% were neutral and 21% posterior. All Gruen zones had an intact cement mantle and 100% of stems had Barrack A or B cement/bone interfaces. No sinkage has been identified on plain AP and lateral radiographs.
The Olympia has only been used at 3 centres until the 10 year clinical and radiographic results were available. The results at 10 years justify further evaluation. It is crucial that meticulous detail to cement technique is adhered to in the operative technique. The ease of insertion and natural anteversion has given confidence to surgeons in training.
The abstracts were prepared by Mr Matt Costa and Mr Ben Ollivere. Correspondence should be addressed to Mr Costa at Clinical Sciences Research Institute, University of Warwick, Clifford Bridge Road, Coventry CV2 2DX, UK.