Background: Mobile-bearing knee designs represent an alternative to conventional fixed-bearing TKA designs. We present the results of a prospective, long-term clinical follow-up study of the Rotaglide (Corin UK) rotating – translating platform total knee design.

Methods: Between October 1990 and December 1998, 326 primary consecutive knee replacements were performed in 260 patients (223 women and 37 men). The average age of the patients at the time of the index procedure was 66.84 years (range 20–82 years). Osteoarthritis was the etiologic factor in 297 knees (91.10%) and rheumatoid arthritis in 25 knees (7.66%). Twenty knees (6.13%) had previous operations (including 16 osteotomies). Both femoral and tibial components were cemented in all knees and the patellae were resurfaced in 199 knees (61.04%). The polyethylene (GUR 1050) mobile inlay was at that time sterilized by Gamma irradiation (2.5 Mrad), packed and stored in air permeable ‘paper bag’. Patients were evaluated at three and six months post operatively and yearly thereafter with use of the KSS. In addition, a radiographic analysis of the tibial, femoral, and patellar components was carried out at each interval and at the last assessment. Twenty four knees (7.36%) were excluded from the study out of which ten knees (3.07%) of eight patients who had died and fourteen knees (4.29%) of ten patients who were lost to follow up. Thus 302 knees (92.64%) were assessed clinically and radiologically in 242 patients. Average follow-up 12.13 years (range 9 to 17).

Results: Pre-operative KSS Knee score 30 (range, 22 to 56) and KSS function score 39 (range, 32 to 58) improved to 88 (range, 62 to 96) and 85 (range, 56–95) respectively. Knee alignment was achieved in 279 out of 302 knees (92.38%). Knee stability was achieved in 292 knees (96.68%). Knee flexion was improved from an average of 92 degrees pre-op to an average of 113 degrees post-operatively. Zonal radiographic analysis revealed fourteen (4.63%) instances of radiolucent lines, ten of which measured < 1 mm in width. None of these lines were deemed to be progressive. Four of the remaining knees with a radiolucent line > 2 mm followed-up carefully and three of them eventually were revised. There were twenty four (7.36%) failures that resulted in revision surgery. In seventeen (5.21%) of them the findings were those of worn out or broken polyethylene with no sings of metal wear or component loosening and therefore only polyethylene exchange was carried out. The other seven knees (2.15%) were totally revised. Kaplan-Meier survivorship using revision of polyethylene mechanical failure as the end point was 94.76%. Overall survivorship of the implant at seventeen years was 92.64%.

Conclusions: This mobile-bearing, total knee prosthesis was associated with a good survival rate and demonstrated clinical efficacy during the 9 to 17 years follow-up interval.

Purpose : The purpose of our study is to present, our long term experience of a total knee joint arthroplasty using a mobile bearing polyethylene platform.

Material and Method : From 1990 to 1998 we operated 324 knees in 259 patients. During the last follow-up 301 knees were assessed in 241 patients.

7 patients died (9 knees) and 11 patients did not attend.

The postoperative follow-up time ranged from 4–12 years (average 8,5 yrs).

207 patients were women (265 knees) and 34 were men (36 knees) aged from 20 to 82 years (average 67,2yrs) at the time of operation.

275 patients suffered from osteoarthritis, 23 from rheumatoid arthritis and 3 from avascular necrosis.

Results : The preoperative and postoperative evaluation was done according to the British Orthopaedic Association Knee Assessment Chart. The knee pain was improved in all of our patients. The knee flexion was improved from an average of 87° pre-op to an average of 113° post-op.

The pre-op valgus deformity was corrected in 24 from 26 knees and the varus was corrected in 157 from 172 knees.

Postoperative alignment was achieved in 286 knees (94,65%).

Radioluscent line was observed in 14 knees (in 6 knees < 1mm and in 8 knees 1–2mm of thickness).

There were 7 complications of the prosthesis needing re-operation.

In 6 cases wear and breakage of the polyethylene and in 1 dislocation of the meniscus was confirmed.

Conclusion : The Rotaglide T.K.R is a reliable solution with satisfactory long-term results. The prosthesis design allows correction of a small rotational malalignment of the femoro–tibial axis. In our patients we did not observe any component loosening and there was no need for re-operation and metal component replacement.

We recommend the use of Rotaglide total knee replacement in more active and biologically young patients when needed.