Objective To evaluate the influence of patellar replacement on total knee arthroplasty by comparing with non pattelar replacement. Methods Between September 2010 and November 2010, 63 patients (63 knees) with osteoarthritis who met the selection criteria and underwent total knee arthroplasty, were randomly divided into 2 groups: patellar replacement in 32 cases (replacement group), non patellar replacement in 31 cases (non pattelar replacement group). There was no significant difference in gender, age, disease duration, osteoarthritis grading, the clinical and functional scores of American Knee Society Score (KSS), the patellar tilt angle, tibiofemoral angle, and patellar ligament ratio between 2 groups (P gt; 0.05), they were comparable. After 6 weeks, 3, 6, and 12 months of operation, clinical and imaging evaluation methods were used to assessment the effectiveness. Results Primary healing of incision was obtained in all patients of 2 groups. Deep venous thrombosis occurred in 6 cases of replacement group and in 8 cases of non pattelar replacement group. All patients were followed up 12 months. The postoperative incidence of anterior knee pain in replacement group was significantly lower than that in non pattelar replacement group (P lt; 0.05) at 3, 6, and 12 months after operation. No significant difference was found in the postoperative KSS clinical score between 2 groups at each time point (P gt; 0.05). The joint function score of the replacement group was significantly higher than that of the non pattelar replacement group at the other time point (P lt; 0.05) except the score at 6 weeks and 3 months. Significant difference was found in the patella score between 2 groups at 12 months (P lt; 0.05), but no significant difference at the other time points (P gt; 0.05). X-ray film showed no patellar fracture and dislocation, or loosening and breakage of internal fixation. At 12 months after operation, the tibiofemoral angle, the patellar ligament ratio, and the patellar tilt angle showed no significant difference between 2 groups (P gt; 0.05). Conclusion Patella replacement can improve knee function score and the patella score, and reduce the incidence of postoperative anterior knee pain.
Objective To investigate the impact of difference between the medial and lateral posterior condyle cartilage thickness on osteotomy in total knee arthroplasty (TKA) by measuring the thickness of the medial and lateral femur posterior condylar cartilage and the posterior condylar angle (PCA) in osteoarthritis (OA) patients. Methods Between May and December 2011, 53 OA patients (60 knees) scheduled for TKA met the inclusion criteria (OA group). There were 12 males (14 knees) and 41 females (46 knees), aged 57-82 years (mean, 71.9 years). The tibiofemoral angle was (183.2 ± 2.6) ° . Fifteen healthy volunteers (30 knees) were taken as controls (control group); there were 6 males and 9 females, aged 59-68 years (mean, 66.3 years). MRI scan data were imported into Mimics10.01 medical image control system to measure the thickness of femur posterior condylar cartilage and the PCA with and without femur posterior condylar cartilage. Results In the control group, the thickness of the medial and lateral femur posterior condylar cartilage was (1.85 ± 0.33) mm and (1.92 ± 0.27) mm respectively, the PCA with and without femur posterior condylar cartilage was (5.0 ± 0.9)° and (5.1 ± 0.8)° respectively, all showing no significant differences (P gt; 0.05). In OA group, the thickness of the medial and lateral femur posterior condylar medial cartilage was (0.45 ± 0.40) mm and (1.78 ± 0.51) mm respectively, the PCA with and without femur posterior condylar cartilage was (3.3 ± 1.7)° and (4.8 ± 1.8)° respectively, all showing significant differences (P lt; 0.05). In OA group, the difference between lateral and medial cartilage thickness was (1.33 ± 0.45) mm, and the difference between PCA with and without femur posterior condylar cartilage was (1.5 ± 1.3)°. There was a positive correlation between the difference of cartilage thickness and the difference of PCA (r=0.75, P=0.01). Conclusion There is significant difference between medial and lateral femur posterior condylar cartilage wear, which leads to difference of PCA. The difference will impact knee function and longevity of the prosthesis, so the difference should be considered during osteotomy.
Objective To investigate the role of β-catenin in pathogenesis and progression of knee primaryosteoarthritis (OA) by detecting the expression of β-catenin. Methods Between October 2010 and May 2011, 40 cartilagespecimens were collected from adult knee primary OA patients undergoing total knee arthroplasty and 10 cartilage specimensfrom adult patients suffering from amputation and femoral condylar fracture. All cartilage samples were taken out from femoralcondylar. The decalcified paraffin-embedded sections were prepared and stained with fast green-safranin O to observe thedegeneration of cartilage, then the modified Mankin scale was used to classify the degeneration. The expression of β-cateninwas detected by the immunohistochemistry staining and Western blot. Results According to the Mankin scale, 10 caseshad normal cartilage, 12 had mild degenerative cartilage, and 28 had moderate to severe degenerative cartilage. The histologicalobservation showed the mild degenerative cartilage characterized by fissures in the superficial zone of the articular cartilage,decreased chondrocytes, arrangement disorder, and duplicated tidemark; and the moderate to severe degenerative cartilagecharacterized by fissures in the deep zone of the articular cartilage, obviously decreased chondrocytes and cluster, and even fullthicknesscartilage defect. The β-catenin did not expressed in normal articular cartilage; but it expressed in the degenerativecartilage, and the expression was significantly higher in the moderate to severe degenerative cartilage than in mild degenerativecartilage (P lt; 0.05). Conclusion β-catenin plays a significant role in the pathogenesis and progression of knee primary OA,and the mechanism may be the activation of Wnt/β-catenin signaling pathway, which promotes transcri ption of inflammatorygenes and leads to the destruction of articular cartilage.