Abstract
Purpose
The purpose of this study was to investigate the rate of return to work after total knee arthroplasty (TKA).
Materials and Methods
105 knees of 80 cases were tested after TKA surgery. 18 knees of 14 cases were men and 87 knees of 66 cases were women. The average age at the time of surgery was 71.5 years, and the average postoperative observation period was 25.5 months. All patients were with osteoarthritis of the knee. The use models were Hi-tech Knee II (Nakashima Medical, Okayama, Japan) CR type 99 knees and PS type 6 knees. The rate of return to work after surgery and employment rate of before and after surgery were examined for all cases. In addition,[1]age at surgery [2]ROM [3]JKOM score(Akai 2006) [4]Knee Society score (KSS Insall 1989) were examined in each case, and found the factors influenced on employment rate after TKA. The occupation was classified using major group of the International Standard Classification of Occupations (ISCO-08) defined by International Labour Organization (ILO) on 2007. Mann-Whitney U test was used for the statistical work.
Results
Preoperative and postoperative employment state was shown in the Fig.1. 29 knees of 23 cases were in employment before surgery. In these cases, 22 knees of 18 cases had return to work after surgery (Group I) and 7 knees of 5cases had retired after surgery(Group II). 76 knees of 57cases were unemployed before and after surgery(Group III). Return to work rate was 78.3 percent after TKA. In the Group I, all cases returned to the same occupation before surgery. The average age of the Group III at the time of surgery was significantly higher than Group I and II(Fig.2). Compared KSS, postoperative functional score of the group I was significantly higher than Group II and III(Fig.3).
Discussion
The cases employed before TKA were younger than the unemployed cases. In the cases returned to work after TKA, stairs rise-and-fall capability and walking ability were higher than the other cases.
Conclusion
(1)The rate of return to work was 78.3 percent after TKA.(2)Age at surgery influenced the preoperative employment.(3)Stairs rise-and-fall capability and walking ability after surgery involved the return to work.
