Regaining the walking ability is one of the main purposes of total knee arthroplasty (TKA). Improving the activities of daily living is a key of patient satisfaction after TKA. However, some patients do not gain enough improvement of ADL as they preoperatively expected, and thus are not satisfied with the surgery. The purpose of this study is to clarify the relationship between preoperative and postoperative physical functional status and whether preoperative scoring can predict the postoperative walking ability. Consecutive 136 patients who underwent total knee arthroplasty for osteoarthritis were prospectively assessed. The average age (±SD) was 74±7.7 and 74% of the patients was female. Berg Balance Scale (BBS) was assessed preoperatively and one year after the surgery. The time needed for 10m walking, muscle power for knee extension and flexion, visual analog scale (VAS) for pain in walking, and necessity of canes in walking were also assessed at one year after the surgery. Multivariate correlation analysis was performed for each parameter. Speaman rank correlation coefficient revealed that preoperative BBS was significantly correlated with the time needed for 10m walking (ρ=0.66, p<0.001). Logistic regression analysis also revealed that preoperative BBS is also correlated with the necessity for canes in walking one year after the surgery. The cut-off value of preoperative BBS for the necessity of canes in walking by ROC curve analysis was 48 points with 79% in sensitivity and 80% in specificity. The muscle powers were also weakly correlated with the walking ability at one year after the surgery, but VAS for pain was not. The study indicated that preoperative physical balance could predict the ability of walking one year after TKA regardless of the reduction of pain. It is suggested that surgery should be recommended before the physical balance function deteriorates to achieve the better walking ability after the TKA

Objectives

Osteophytes are products of active endochondral and intramembranous ossification, and therefore could theoretically provide significant efficacy as bone grafts. In this study, we compared the bone mineralisation effectiveness of osteophytes and cancellous bone, including their effects on secretion of growth factors and anabolic effects on osteoblasts.

We compared the alignment of 39 total knee replacements implanted using the conventional alignment guide system with 37 implanted using a CT-based navigation system, performed by a single surgeon. The knees were evaluated using full-length weight-bearing anteroposterior radiographs, lateral radiographs and CT scans.

The mean hip-knee-ankle angle, coronal femoral component angle and coronal tibial component angle were 181.8° (174.2° to 188.3°), 88.5° (84.0° to 91.8°) and 89.7° (86.3° to 95.1°), respectively for the conventional group and 180.8° (178.2° to 185.1°), 89.3° (85.8° to 92.0°) and 89.9° (88.0° to 93.0°), respectively for the navigated group.

The mean sagittal femoral component angle was 85.5° (80.6° to 92.8°) for the conventional group and 89.6° (85.5° to 94.0°) for the navigated group.

The mean rotational femoral and tibial component angles were −0.7° (−8.8° to 9.8°) and −3.3° (−16.8° to 5.8°) for the conventional group and −0.6° (−3.5° to 3.0°) and 0.3° (−5.3° to 7.7°) for the navigated group.

The ideal angles of all alignments in the navigated group were obtained at significantly higher rates than in the conventional group. Our results demonstrated significant improvements in component positioning with a CT-based navigation system, especially with respect to rotational alignment.