Stemmed Prosthesis in Revision TKA

Bae, Dae Kyung; Kim, Kang Il; Jun, Myoung Ho; Cha, Jae Ryong

Abstract

PURPOSE
To analyze functional and radiological results after revision TKA using stemmed prosthesis in patients with severe bone defects. MATERIAL AND METHODS: From January 1990 to April 1997, 77 revision TKAs were performed in 67 patients by one surgeon. Fluted diaphyseal intramedullary stems were used in 31 cases with severe bone defects. Metal wedges, augments and bone grafts were used to fill osseous defects when necessary. The average interval between the index arthroplasties and the revision was 6 years and 2 months. The average duration of follow-up was 3 years and 1 month. The causes of revision TKAs included wear in 20 joints, infection in 5, aseptic loosening in 3, ankylosis in 2 and breakage of tibial component in one.
RESULTS
The average preoperative knee score, according to the rating scale of The Hospital for Special Surgery, was 63 points and improved to 90 points postoperatively. The average preoperative range of motion was 95 degrees and improved to 125 degrees postoperatively. Radiologically, two cases showed radiolucencies without progression at the interface between bone and cement. At the uncemented stem-to-bone interface, thin radiopaque line developed near the metal in 14 cases. All cases showed no subsidence of components or changes in alignment.
CONCLUSION
This technique using a stemmed prosthesis was effective for revision total knee arthroplasty in patients with severe bone defect and instability.