Effect of posterior tibial slope on the short-term outcome in mobile-bearing unicompartmental knee arthroplasty / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the relationship between postoperative knee function and the sagittal position of tibial component in unicompartmental knee arthroplasty (UKA).@*METHODS@#We retrospectively enrolled the patients who underwent UKA from January 2016 to May 2020. They were assigned into 2 groups according to postoperative posterior tibial slope (PTS): the normal PTS group (PTS≥3° and PTS < 8°) and the abnormal PTS group (PTS < 3° or ≥8°). The patients were followed up for at least 12 months. The postoperative Knee Society Clinical Score (KSS-C), Knee Society Functional Score (KSS-F) and knee range of motion (ROM) were compared between the two groups.@*RESULTS@#A total of 72 patients (82 knees) were included with 51 patients (58 knees) in PTS normal group and 21 patients (24 knees) in PTS abnormal group. All the patients were followed up with median of 23.6 months. There was no significant difference in the general data [gender, age, body mass index (BMI)], pre-operative knee range of motion, preoperative KSS-C score and KSS-F score (P > 0.01). The KSS-C score, KSS-F score, and knee range of motion significantly improved after surgery (P < 0.01) for all the patients. The postoperative KSS-C score in normal PTS group (88.76±2.79) was significantly higher than the KSS-C score in abnormal PTS group (84.42±3.35, P < 0.01), but no significant difference between the 2 groups was observed in postoperative KSS-F score and knee range of motion (P > 0.01). In addition, there was no correlation between the change of PTS and postoperative KSS-C score (r=-0.034, 95%CI: -0.247 to 0.186, P = 0.759), KSS-F score (r = -0.014, 95%CI: -0.238 to 0.198, P = 0.901) and knee range of motion (r= 0.045, 95%CI: -0.214 to 0.302, P = 0.686).@*CONCLUSION@#The posterior tibial slope between 3° and < 8° can be recommended to improve knee joint function in mobile UKA, and excessive or insufficient PTS should be avoided.

Plant homeodomain finger protein 23 inhibits autophagy and promotes apoptosis of chondrocytes in osteoarthritis / 中华医学杂志(英文版)

Background@#Plant homeodomain finger protein 23 (PHF23) is a novel autophagy inhibitor gene that has been few studied with respect to orthopedics. This study was to investigate the expression of PHF23 in articular cartilage and synovial tissue, and analyze the relationship between PHF23 and chondrocyte autophagy in osteoarthritis (OA).@*Methods@#Immunohistochemical staining and western blot were applied to show the expression of PHF23 in cartilage of different outbridge grades and synovial tissue of patient with OA and healthy control. The normal human chondrocyte pre-treated with rapamycin or 3-methyladenine, treated with interleukin-1β (IL-1β). IL-1β induced expression level of PHF23 and autophagyrelated proteins light chain 3B-I (LC3B-I), LC3B-II, and P62, were examined by Western blot. A PHF23 gene knock-down model was constructed with small interfering RNA. Western blot was performed to detect the efficiency of PHF23 and the impact of PHF23 knockout on IL-1β-induced expression of autophagy-related and apoptotic-related proteins in chondrocyte.@*Results@#The expression of PHF23 was significantly increased in the high-grade cartilage and synovial tissue of patients with OA. The IL-1β-induced expression of PHF23 was gradually enhanced with time. The level of LC3B-II, P62 changed with time. After knockdown of PHF23, the level of autophagy-related proteins increased and apoptotic-related proteins decreased in IL-1β-induced OA-like chondrocytes.@*Conclusions@#The expression of PHF23 increased in human OA cartilage and synovium, and was induced by IL-1β through inflammatory stress. PHF23 can suppress autophagy of chondrocytes, and accelerate apoptosis.

Plant homeodomain finger protein 23 inhibits autophagy and promotes apoptosis of chondrocytes in osteoarthritis / 中华医学杂志(英文版)

BACKGROUND@#Plant homeodomain finger protein 23 (PHF23) is a novel autophagy inhibitor gene that has been few studied with respect to orthopedics. This study was to investigate the expression of PHF23 in articular cartilage and synovial tissue, and analyze the relationship between PHF23 and chondrocyte autophagy in osteoarthritis (OA).@*METHODS@#Immunohistochemical staining and western blot were applied to show the expression of PHF23 in cartilage of different outbridge grades and synovial tissue of patient with OA and healthy control. The normal human chondrocyte pre-treated with rapamycin or 3-methyladenine, treated with interleukin-1β (IL-1β). IL-1β induced expression level of PHF23 and autophagy-related proteins light chain 3B-I (LC3B-I), LC3B-II, and P62, were examined by Western blot. A PHF23 gene knock-down model was constructed with small interfering RNA. Western blot was performed to detect the efficiency of PHF23 and the impact of PHF23 knockout on IL-1β-induced expression of autophagy-related and apoptotic-related proteins in chondrocyte.@*RESULTS@#The expression of PHF23 was significantly increased in the high-grade cartilage and synovial tissue of patients with OA. The IL-1β-induced expression of PHF23 was gradually enhanced with time. The level of LC3B-II, P62 changed with time. After knockdown of PHF23, the level of autophagy-related proteins increased and apoptotic-related proteins decreased in IL-1β-induced OA-like chondrocytes.@*CONCLUSIONS@#The expression of PHF23 increased in human OA cartilage and synovium, and was induced by IL-1β through inflammatory stress. PHF23 can suppress autophagy of chondrocytes, and accelerate apoptosis.

Measurement of the tibial alignment after total knee replacement without the extramedullary cutting guide / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the accuracy and analysis of the influencing factors of the tibia prosthetic coronal alignment after total knee arthroplasty without tibia extramedullary cutting guide.@*METHODS@#In the study, 76 patients (96 knees) who had primary total knee arthroplasty in Peking University First Hospital from February 2012 to April 2016 were selected retrospectively. All of the cases were performed by the same experienced orthopedic surgeon team. The patients were divided into 2 groups randomly: tibia cutting without guide group and tibia cutting with extramedullary guide group. Lower extremity standard anterior and posterior X-ray films of the knees were taken before and after surgery, and the anatomical tibial angle (AT), the posterior slope angle (PSA) before and after surgery, the tibia component angle (TCA) were measured in the X-ray films. We also recorded the beginning and finishing time of the operation, the operation sequence of the day respectively at the same time. The data were analyzed by correlation analysis, t test and chi square test between the two groups.@*RESULTS@#The age, gender, body mass index, AT/PSA before the surgery and TCA/PSA after the surgery of the two groups were no significant differences (P>0.05). The rate of 90-TCA≥ 3° was 31.5% (17 knees) and 31% (12 knees) respectively, there were no significant differences (P=0.956) between the two groups. The postoperative TCA of two groups was not correlated with age, gender, body mass index (BMI), operation side (P>0.05), there was also no correlation between the postoperative TCA and the start time of the operation, the whole operation time, and the operation sequence of the day (P>0.05). The two groups were divided into subgroups according to 90-AT before the operation (0°≤90-AT<3°, 3°≤90-AT<5°, 5°≤90-AT<8°, 90-AT≥8°), and there was no difference among them. But we found there was a much higher rate of 90-TCA<3° in the group without cutting guide than the group with extramedullary guide when 90-AT≥8° before the surgery (the rates were 71.4 % and 42.9%, P<0.05).@*CONCLUSION@#There is no significant difference of the tibia prosthetic coronal alignment accuracy between the tibia cutting without guide and the traditional extramedullary guided bone cutting by experienced surgeons. Only if when patients already have suffered severe malformation of knee joint (90-AT≥8°) before the operation, tibia cutting without cutting guide is more effective to rectify the tibia prosthetic coronal alignment.

Intraarticular Injection of Allogenic Mesenchymal Stem Cells has a Protective Role for the Osteoarthritis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Researchers initially proposed the substitution of apoptotic chondrocytes in the superficial cartilage by injecting mesenchymal stem cells (MSCs) intraarticularly. This effect was termed as bio-resurfacing. Little evidence supporting the treatment of osteoarthritis (OA) by the delivery of a MSC suspension exists. The aim of this study was to investigate the effects of injecting allogenic MSCs intraarticularly in a rat OA model and to evaluate the influence of immobility on the effects of this treatment.</p><p><b>METHODS</b>We established a rat knee OA model after 4 and 6 weeks and cultured primary bone marrow MSCs. A MSC suspension was injected into the articular space once per week for 3 weeks. A subgroup of knee joints was immobilized for 3 days after each injection, while the remaining joints were nonimmobilized. We used toluidine blue staining, Mankin scores, and TdT-mediated dUTP-biotin nick end labeling staining to evaluate the therapeutic effect of the injections. Comparisons between the therapy side and the control side of the knee joint were made using paired t-test, and comparisons between the immobilized and nonimmobilized subgroups were made using the unpaired t-test. A P value < 0.05 was considered significant.</p><p><b>RESULTS</b>The three investigative approaches revealed less degeneration on the therapy sides of the knee joints than the control sides in both the 4- and 6-week groups (P < 0.05), regardless of immobilization. No significant differences were observed between the immobilized and nonimmobilized subgroups (P > 0.05).</p><p><b>CONCLUSIONS</b>Therapy involving the intraarticular injection of allogenic MSCs promoted cartilage repair in a rat arthritis model, and 3-day immobility after injection had little effect on this therapy.</p>

Characterization of human primary chondrocytes of osteoarthritic cartilage at varying severity / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>There is a difficulty in evaluating the in vivo functionality of individual chondrocytes, and there is much heterogeneity among cartilage affected by osteoarthritis (OA). In this study, in vitro cultured chondrocytes harvested from varying stages of degeneration were studied as a projective model to further understand the pathogenesis of osteoarthritis.</p><p><b>METHODS</b>Cartilage of varying degeneration of end-stage OA was harvested, while cell yield and matrix glycosaminoglycan (GAG) content were measured. Cell morphology, proliferation, and gene expression of collagen type I, II, and X, aggrecan, matrix metalloproteinase 13 (MMP-13), and ADAMTS5 of the acquired chondrocytes were measured during subsequent in vitro culture.</p><p><b>RESULTS</b>Both the number of cells and the GAG content increased with increasing severity of OA. Cell spreading area increased and gradually showed spindle-like morphology during in vitro culture. Gene expression of collagen type II, collagen type X as well as GAG decreased with severity of cartilage degeneration, while expression of collagen type I increased. Expression of MMP-13 increased with severity of cartilage degeneration, while expression of ADAMTS-5 remained stable. Expression of collagen type II, X, GAG, and MMP-13 substantially decreased with in vitro culture. Expression of collagen type I increased with in vitro cultures, while expression of ADAMTS 5 remained stable.</p><p><b>CONCLUSIONS</b>Expression of functional genes such as collagen type II and GAG decreased during severe degeneration of OA cartilage and in vitro dedifferentiation. Gene expression of collagen I and MMP-13 increased with severity of cartilage degeneration.</p>

Acetabular revision using acetabular reinforcement cages with a hook / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the effects of cementless revising cup or acetabular reinforcement cages for reconstructing the massive acetabular deficiency.</p><p><b>METHODS</b>From September 2001 to September 2008, 22 loosening acetabular cases (24 hips) were revised using cementless revising cup or acetabular reinforcement cases for reconstructing massive bone defect after particulate bone grafting. There were 2 cases (2 hips) using Lima cementless revising cup, 2 cases (2 hips) using Kerboull ring, and 18 cases (20 hips) using restoration GAP cages. Six cases (6 hips) were male, and 16 cases (18 hips) were female. The mean age was 62 years old (34 - 79 years old). Septic loosening was in 2 cases (2 hips), and aseptic loosening in 20 cases (22 hips). The mean follow-up was 48 months (18 - 84 months).</p><p><b>RESULTS</b>There was no clinical or radiological evidence of loosening for the revising acetabular components at the last follow-up point. The mean Harris hip score was improved significantly from 56 points (44 - 75) before revision to 89 points (78 - 94) at the last follow-up after revision. Excellent and good rate was 95.5% (21/22 cases). The average abduction angle of the three types of acetabular reconstructive cages were 50.1 degrees (39.0 degrees - 66.0 degrees), and almost all cases of the hip rotation center were restored after revision surgery. At the last follow-up, the reinforcement cages were no immigration and breakup, and there was no radiolucent line around the acetabular components. The bone graft integrated well into surrounding acetabular bone.</p><p><b>CONCLUSION</b>The method of revising the massive acetabular bone defect by cementless revising cup and acetabular reinforcement cages restores the normal hip rotation center, supplies the primary stability of the revising component, and protects the bone graft from mechanical overload during its revascularization phase, which is a reliable method for revising the massive acetabular deficiency after total hip arthroplasty.</p>