Introduction The aim of this study was to describe the migration pattern of the Exeter stem after revision with morsellised allograft bone and cement, to evaluate if restricted weight bearing had any influence on migration, and to measure, before and after revision, the quality of life comparing it to primary cemented hip arthroplasties.

Methods Forty-one consecutive stem revisions were followed by radiostereometry (RSA, 1. Selvik 1989). The accuracy of the RSA set-up was between 0.3 mm and 0.7 mm. The surgical procedure described by the Exeter group (2. Gie 1993) was used. All were first time revisions for aseptic loosening and all patients had had their primary arthroplasty for osteoarthritis. Bone stock deficiency was classified according to Gustilo and Pasternak. Sixteen were type I, 20 type II, five type III but none was classified as type IV. The Nottingham Health Profile was used to measure quality of life before and after revision.

Results All stems migrated distally and most of them also migrated medially or laterally and posteriorly. Migration was still observed in one third of stems between 1.5 and two year follow-ups. At two years stem subsidence averaged 2.5 mm, medial or lateral migration averaged 1.2 mm and posterior migration averaged 2.9 mm. No correlation to the pre-operative bone stock deficiency was observed. Between two and five years only marginal migration occurred in 12 of the 15 stems followed for five years. No differences in the migration pattern were detected when free weight bearing was allowed immediately after revision in hips without intra-operative skeletal complications compared to when restricted weight bearing was practiced. Most migration occurs within the first two weeks after surgery. NHP scales for pain, physical mobility, sleep and energy scales improved significantly. NHP scores were in all six scales comparable to those of primary arthroplasties. No rerevision was performed and no stem had radiographic sings of loosening.

Conclusions Most migration occurred early after revision and decreased gradually. Marginal migration after two years does not deteriorate the results during the first five years after surgery. Quality of life (patient outcome) after revision with impacted morsellised allograft bone and cement was comparable to that of primary arthroplasties.

In relation to the conduct of this study, one or more of the authors is in receipt of a research grant from a non-commercial source.

Aim: To investigate the migration and rotation patterns of the socket in hip revisions with impacted morselized allograft bone and cement. Methods: 17 Exeter socket revisions were followed by radiostereometry (RSA) and radiography for 5 years. The surgical procedure described by the Nijmegen group in Netherlands was used. The allograft bone chips were prepared in a bone mill and had an approximate size of 3 mm. Results: All but 1 socket migrated proximally (accuracy 0.2 mm).

Five socket revisions with a radiolucent line > 2 mm in at least 1 zone had a migration and a rotation rate 2–5 times larger (broken lines) than 12 socket revisions (unbroken lines) without a radiolucent line > 2 mm. Allograft resorption in at least 2 zones was observed in all these 5 revisions but in 4 of them no progression of the radiolucent line was seen after the 2 years and there was no clinical deterioration or threat to bone stock.

In 8 of the revisions radiographic signs of trabecular incorporation or remodeling of the graft were observed. No rerevision was performed. Conclusions: Further follow-up is needed for evaluation of the clinical relevance of radiolucent lines in impaction grafting. As a consequence of these findings a RSA study using larger bone chips has been started.

Aim: To find out when, at which interface, and to what extent migration of the Exeter stem after revision with morselized allograft bone and cement takes place and to evaluate if restricted weight bearing had any influence on the migration pattern. Methods: 40 stem revisions were followed by radiostereometry (RSA). The surgical procedure described by the Exeter group in England (Gie et al 1993) was used. Results: Most migration occurs within the first weeks after surgery. The Exeter stem migrates “within” the cement mantle and the stem-cement beam also migrates relative to femur.

All stems migrated distally and most of them also migrated medially or laterally and posteriorly. Migration was still observed in one third of stems between 1.5 and 2-year follow-ups. At 2 years stem subsidence averaged 2.5 mm, medial or lateral migration averaged 1.2 mm and posterior migration averaged 2.9 mm. No correlation to the preoperative bone stock deficiency was observed. Between 2 and 5 years only marginal migration occurred in 11 of the 15 stems followed for 5 years.

No differences in the migration pattern were detected when free weight bearing was allowed immediately after revision in hips without intraoperative skeletal complications as compared to when restricted weight bearing was practiced. No rerevision was performed. Conclusions: Most migration occurs early. Subsidence occurs of the stem within the cement mantle and of the stem-cement beam. Many stems migrate marginally even after 2 years but this does not deteriorate the results during the first five years. Restricted weight bearing postoperatively in uncomplicated cases might not be needed.