A Meta-Analysis of Patellar Replacement in Total Knee Arthroplasty for Patients With Knee Osteoarthritis.

BACKGROUND: This meta-analysis (MA) aims at comparing the clinical outcomes of resurfacing and nonresurfacing the patella in patients undergoing total knee arthroplasty in the treatment of knee osteoarthritis. METHODS: Randomized controlled trials were included by retrieving data from electronic English databases. Both fixed and random-effects models were employed, and standardized mean difference and 95% confidence intervals were calculated. Stata13.1 software was used for statistical analysis for all the studies included to compare the differences in improving Knee Society Clinical Score and Knee Society Function Score as well as the reduction in rates of infection, reoperation, and anterior knee pain. RESULTS: A total of 394 studies were initially included in this MA. About 20 randomized controlled trials which met the inclusion criteria were finally enrolled in this MA. The results of our MA showed that the reoperation rate of the patellar resurfacing group was lower than that of the nonresurfacing group. The subgroup analysis was performed according to the follow-up time and revealed that the increase in the Knee Society Clinical Score was higher in the patellar resurfacing group than that in the nonresurfacing group in the follow-up period of 1 to 2 years. The risk of reoperation rate was lower in the patellar resurfacing group than that in the nonresurfacing group, while there were no statistical differences in the follow-up time over 2 years. CONCLUSION: Our study suggests that during the follow-up of 1 to 2 years, patellar resurfacing can significantly increase the Knee Society Clinical Score and reduce the reoperative rates in patients with knee osteoarthritis.

Effect of autologous platelet-rich plasma on the chondrogenic differentiation of rabbit adipose-derived stem cells in vitro.

This study aimed to isolate rabbit adipose-derived stem cells (ADSCs) and explore the potential of platelet-rich plasma (PRP) in the chondrogenic differentiation of ADSCs, thereby potentially providing a new approach for the repair and regeneration of cartilage injury. Rabbit ADSCs were isolated and characterized by induction towards adipogenic, osteogenic and chondrogenic lineages in vitro. The isolated ADSCs were also cultured with or without 10% PRP. Immunofluorescence staining, toluidine blue staining and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were used to detect type II collagen (Col II) and aggrecan (AGC) expression. Col II immunofluorescence staining and toluidine blue staining indicated that following induction by autologous PRP, ADSCs manifested Col II and AGC expression. The expression of Col II and AGC mRNA was significantly upregulated in the PRP-treated cells when compared with that in control cells. Autologous PRP produced by laboratory centrifugation was able to promote the chondrogenic differentiation of rabbit ADSCs in vitro.

[Comparison of therapeutic effects between patella replacement and patella osteotomy in total knee arthroplasty: a case-control study].

OBJECTIVE: To compare therapeutic effects between patella replacement and patella osteotomy in total knee arthroplasty. METHODS: From April 2004 to April 2011, 52 patients (54 knees) were enrolled in the clinical trail of total knee arthroplasty, who received patella replacement (24 knees, including 13 males and 11 females,ranging in age from 53 to 78 years old or patella osteotomy (30 knees,including 16 males and 12 females,ranging in age from 55 to 79 years old. The average follow-up period was 56 months,ranging from 20 to 80 months. The American HSS Score for knee, the Feller score for patella, range of motion (ROM) for knee, patient satisfaction and complications related to the patella were used to evaluate therapeutic effects. RESULTS: In the patella replacement group,the preoperative and final follow-up HSS scores of patients were 38.4 +/- 8.2 and 91.2 +/- 8.6 respectively; Feller scores were 13.6 +/- 6.2 and 25.2 +/- 4.2; scores of anterior knee pain were 3.9 +/- 3.2 and 11.2 +/- 3.7; ROM were (78 +/- 26) degrees and(108 +/- 18) degrees. In the patella osteotomy group,the preoperative and final follow-up HSS scores of patients were 39.5 +/- 8.4 and 91.0 +/- 8.5 respectively;Feller scores were 13.4 +/- 6.5 and 25.6 +/- 4.0; scores of anterior knee pain were 3.7 +/- 3.1 and 11.3 +/- 3.6; ROM were (76 +/- 27) degrees and (110 +/- 19) degrees. In the patella replacement group,patient's satisfaction was 91%, and complication related to the patella was 16.7%; in the patella osteotomy group, patient's satisfaction was 89%, and complications related to the patella was 10.0%. There were no statistically significant differeneces in final follow-up HSS scores, Feller scores, scores of anterior knee pain and ROM between the two groups. However,there was no significant difference of patient's satisfaction between them. There was statistically significant differenece of patella-related complications between the two groups, and the complication rate in the patella replacement group was higher than that in the patella osteotomy group. CONCLUSION: Total knee arthroplasty with patella replacement or patella osteotomy dramatically relieves pain and improves the knee function. Patella-related complications are associated with its treatment methods, but post-operative anterior knee pain and patient's satisfaction are not related to treatment methods of the patella.