Abstract
Purpose
To compare and analyze the long term follow up clinical & radiological result after utilization of fixed-type & rotating-type implant for high flex both total knee replacement.
Subject & Method
This paper targeted 45 patients, 90 cases that got high flex both total knee replacement with utilization of fixed-type implant(LPS-flex®) & rotating-type implant(P.F.C® Sigma RP-F) for 1 patient by 1 operator(C.C.H) in our hospital from 2005.01 to 2006.11. Preoperative diagnoses were degenerative arthritis (43 patients, 86 cases), rheumatic arthritis (2 patients, 4 cases), mean age at the operation was 66.4 years old(54∼78), 3 men, 42 women, mean follow up period was 110.8months(97∼120). We compared and estimated Hospital for Special Surgery(HSS) score and Knee Society Score(KSS), Western Ontario and MacMaster Universities Osteoarthritis(WOMAC) score and mean range of motion of knee joint at pre-operation and last follow up for functional & clinical evaluation. And we compared and estimated change of femorotibial angle and radiolucency through erect AP & lateral x-ray at pre-, post-operation and last follow up using American Knee Society Roentgen Graphic Evaluation for radiological evaluation.
Result
On the result of clinical and functional evaluation, it showed improving outcome in both group(fixed-type implant, rotating-type implant), and there was no statistically significant difference. Mean HSS score was increased from 43.0, 37.1(pre-operation) to 93.2, 92.1(last follow-up), mean KSS score was increased from 37.1, 37.2(pre-operation) to 88.8, 87.6(last follow-up), WOMAC score was also increased from 104.8, 104.4(pre-operation) to 126.1, 128.4(last follow-up). Mean joint range of motion was increased from 104.8, 104.4(pre-operation) to 126.1, 128.4(last follow-up), but there was no significant difference between 2 groups. The change of femorotibial angle was corrected from average introversion 8.2°(pre-operation) to extroversion 4.8°(post-operation) in fixed-type implant group, and average introversion 8.3°(pre-operation) to extroversion 4.8°(post-operation) in rotating-type implant group, and there was no significant difference between 2 groups. And in all cases, there was no change of radiolucency, loosening of implant, or osteolysis at the last follow-up.
Conclusion
It showed good functional, clinical and radiological result on long term follow-up in both groups that got both total knee replacement with utilization of fixed-type implant and rotating-type implant for 1 patient, and there was no statistically significant difference between 2 groups. As a result, it is considered that the selection of implant will be up to the condition of patient and experience of operator and so on.