Outcomes of posterior cruciate substituting total knee arthroplasty.

Abstract

Background: Knee replacements should correct deformity, and give stability, a useful range of movement and, above all, freedom from pain for an acceptable time, preferably the remaining lifetime of the patient.

Objective : To review author's experience with Posterior Cruciate Substituting Total Knee Arthroplasty performed between 1998 and 2008.

Method : One hundred and fourteen consecutive patients, 139 knees, were retrospectively reviewed to determine outcomes, complication and survivorship by comparing preoperative and latest follow - up Knee Society Score,Oxford Knee Function Score with paired t-test statistical analysis (95 %confidence interval).

Result : The average patient age at the time of surgery was 67.29 years (52.0 - 81.8 years). One hundred and four patients (91.2 percent) were diagnosed osteoarthritis. The mean Body Mass Index was 26.42 kg/m2 (16.65 - 36.98).At a mean follow up of 3.27 years (0.5 - 6 years), the mean Knee Society knee scores increased from an average of 36 to 92 points and the function scores increased from 28 to 83 points, the total scores increased from 64 to 176 points with good to excellent outcome rating reported in 135 knees (98.1 percent). The mean Oxford Knee Function Score was better from 45 to 14 points. Singificant improvements in Knee Society knee scores,function scores, total scores and Oxford Knee Scores were seen from preoperative to latest followup assessment (p<0.001). Six knees of total 10 complicated knees were infected. Three revisions were performed for two deep infected cases and 1 aseptic loosening ; one additional patient had radiographic evidence of septic tibial loosening. Three of six cases were superficial wound infections. The mean postoperative flexion arc was 111.7 degree. The cumulative success rate was 94.42 percent at 10 years. The mean annual failure rate was 0.57 percent.

Conclusion : Total knee arthroplasty with cementing of posterior cruciate substituting design total knee prosthesis is considered to be an effective operative treatment with durable results for osteoarthritis when other, less invasive measures have failed.

Keywords : Arthroplasty, Outcomes, Survivorship.