The Swedish Knee Arthroplasty study with special reference to unicompartmental prostheses.

Research output: ThesisDoctoral Thesis (compilation)


The Swedish Knee Arthroplasty study has prospectively registered and followed knee arthroplasties done in Sweden since 1976. Demography, epidemiology and general knee prosthetic biofunction is given for 30,003 primary knee arthro-plasties and their revisions through 1992. The annual number of knee arthroplasties increased fourth fold while the relative use of Unicompartmental knee arthroplasty (UKA) decreased as Tricompartmental knee arthroplasty (TKA) increased. The 5-year Cumulative revision rate (CRR) decreased for each 5-year period studied for TKA in osteoarthrosis (OA) but for UKA no change was seen. The annual percentage of revisions has diminished from 10% to 5% In OA, modern TKA have a lower CRR than UKA, with a 5-year CRR of 3% and 8%, respectively. A problem was identified with the PCA Uni prosthesis (femoral loosening and excessive HDPE wear) and the Oxford Meniscal knee (dislocating meniscus and femoral loosening) with 5-year CRR of 16% and 10% respectively, compared to 5% for the Marmor. Two relatively unchanged prostheses, Marmor and Total Condylar, were used from 1975-1986 with continuous improvement in CRR over time. This indicates that factors other than prosthetic design affect the CRR. In failed UKA for OA, revision with exchange using new unicompartmental components gave a 5-year Cumulative rerevision rate (CRRR) of 26% while conversion to TKA gave 7%. Also addition of components in the contralateral compartment gave an inferior 5-year CRRR of 17%. Failed UKA should be converted to TKA. In comparison modern primary TKA had a CRR of 3%. A cohort of 14,551 patients followed for 66,622 patient years was matched with the Swedish National Cancer Registry. The cancer incidence was not increased after knee arthroplasty.


  • Stefan Lewold
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Orthopedics


  • Skeleton, rerevision, revision, survival analysis, follow-up, Unicompartmental knee arthroplasty, prognosis, muscle system, rheumatology locomotion, Skelett, muskelsystem, reumatologi
Original languageEnglish
Awarding Institution
Supervisors/Assistant supervisor
  • [unknown], [unknown], Supervisor, External person
Award date1997 Nov 6
  • Department of Orthopaedics, Lund University
Print ISBNs91-628-2723-5
Publication statusPublished - 1997
Publication categoryResearch

Bibliographic note

Defence details Date: 1997-11-06 Time: 09:15 Place: Föreläsningssal 1, Centralblocket, Universitetssjukhuset i Lund External reviewer(s) Name: Havelin, Leif I Title: PhD Affiliation: Department of Orthopeadics and Traumatology, Haukeland University Hosdpital, Norway. ---