[Early clinical outcome of total knee arthroplasty for flexion-contracture deformity knees of different degrees].
OBJECTIVE
To make a retrospective analysis on an early clinical outcome of total knee arthroplasty (TKA) for the knees with different degrees of flexion-contracture deformities.


METHODS
Ninety-seven knees of 65 patients undergoing total knee arthroplasty with the Scorpion posterior-stabilized knee prosthesis from January 2000 to December 2003 were reviewed, including 51 osteoarthritis patients (74 knees) and 14 rheumatoid arthritis patients (23 knees). Thirty-three patients underwent unilateral TKA, and 32 patients underwent bilateral TKA. The average range of motion (ROM) before operation was 82.8 degrees (range, 5-140 degrees). According to the preoperative flexion-contracture degrees of the knees, these patients were divided into 2 groups, group A and group B. Group A consisted of the patients with flexion-contracture less than 20 degrees (range, 0-15 degrees), and group B consisted of the patients with flexion-contracture not less than 20 degrees (range, 20-60 degrees). In group A, the average flexion-contracture degree, ROM, KSS (knee society score), and function score were 10.7 +/- 8.0 degrees, 104.6 +/- 20.0 degrees, 29.1 +/- 18.0, and 32.6 +/- 20.7, respectively. But the corresponding data were much worse in group B than in group A, which were 28.2 +/- 7.8 degrees, 60.8 +/- 26.6 degrees, 12.1 +/- 13.2, and 26.8 +/- 18.1. All the operations were primary total knee arthroplasty, and they were performed by the same group of surgeons. The time for the prosthesis installed lasted for 25.6 minutes, and the average tourniquet time was 34.7 minutes. Three or four days after operation, the patients began the continuous passive motion (CPM) and active functional exercise of the knee.


RESULTS
The patients were followed up for an average of 2 years and 7 months(range, 8 mon-3.5 yr). During the follow-up period, the average flexion-contracture degree, ROM, KSS, and function score in group A were 0.4 +/- 2.1 degrees, 108.6 +/- 19.0 degrees, 82.1 +/- 13.8, and 72.3 +/- 29.1, respectively; and the corresponding data in group B were 1.3 +/- 3.2 degrees, 98.6 +/- 16.40, 75.9 +/- 8.2, and 81.4 +/- 26.9, respectively. There was no significant difference between the 2 groups. No revision or deep infection was found.


CONCLUSIONS
The curative effect is mainly determined by the surgeon's good operational skills, rich clinical experience, and familiarity with the prosthesis, and it is not influenced by severity of the knee flexion-contracture deformity. The knee ROM after TKA, which has a "toward middle ROM" phenomenon, is influenced by many clinical factors. It is very important for the patient to perform a functional exercise of the knee as early as possible after operation.
Guan
Zhenping
Z
Arthritis Clinic & Research Center, Peking University People's Hospital, Beijing, 100044, PR China.
Lv
Houshan
H
Shi
Mingguo
M
D000328:Adult; D000368:Aged; D001176:Arthrogryposis / Q000601:surgery*; D019645:Arthroplasty, Replacement, Knee; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000002:abnormalities*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome