Objective To investigate the rotational mismatch of total kneereplacement with medial 1/3 of tibial tuberosity as bony landmark in osteoarthritic patients with varus or valgus deformity. Methods Axial images on computed tomography of 62 knees (including 55 varus deformities and 7 valgus deformities) in 32 Chinese osteoarthritic patients who had total knee arthroplasty were analyzed, compared with that of 10 healthy knees. On images of the distal femur, the angle between the lines of surgical epicondylar axis(SEA) and posterior condylar axis was measured as posterior condylar angle (PCA), and on images of the proximal tibia, a baseline for the anteriorposterior axis of each component was drawn based on the SEA for the femur and the medial 1/3 of the tibial tuberosity for the tibia. The angle between these lines (Angle α) was defined as therotational mismatch between the components when they were aligned to the anatomic landmarks of each bone. Results The sulcus of medial epicondyle of femur could be identified on CT images of over 80% osteoarthritic knees; the median value of PCA was +2.36°, with an individual variation of 0° to +7.5°. Angle α was +6.45±3.68°(range, 0° to +11.8°) in 10 healthy knees, which increased significantly to +10.85±10.47°(range, 0° to +28.1°)in 55 varus knees (P＜0.05), which also increased significantly to +11.6±7.3°(range, -6.5° to +26.8°) in 7 valgus knees (P＜ 0.05). Conclusion With the medial 1/3 of the tibial tuberosity as the rotational landmark for the tibial component, there was a tendency to align the tibial component in external rotational position relative to the femoral component in knees with normal alignment, the rotational mismatch increased in Chinese osteoarthritic knees with varus and valgus deformity.
Objective To investigate the feasibil ity of alendronate (ALN) in treating osteoarthritis (OA) by observing the effects of ALN on interleukin 1β (IL-1β) induced chondrocytes of rat in vitro. Methods The chondrocytes of knee articular surface from 15 SD rats (1-month-old, female or male, weighing 100-150 g) were cultured. The chondrocytes were observed by inverted phase contrast microscope and identified by toluidine blue staining and HE staining. The third passage chondrocytes were divided into 3 groups: the chondrocytes were cultured with DMEM for 5 days in group A, with 10 ng/mL IL-1β for 2 days and with DMEM for 3 days in group B, and with 10 ng/mL IL-1β for 2 days and with 1 × 10-6 mol/L ALN for 3 days in group C. Immunocytochemistry and real-time PCR were performed to determine the expression levels of collagen type II (Col II), matrix metalloproteinase 13 (MMP-13), and β-catenin. Results Toluidine blue staining proved that the cultured cells were chondrocytes. The integrated absorbency (IA) value of Col II in group C (10.290 7 ± 0.499 2) was lower than that in group A (15.377 0 ± 0.571 8) and higher than that in group B (5.463 2 ± 0.450 4), showing significant differences (P lt; 0.05). The IA value of MMP-13 in group C (3.068 6 ± 0.205 6) was significantly lower than that in group B (6.998 1 ± 0.329 7, P lt; 0.05), but there was no significant differenc when compared with group A (2.777 5 ± 0.199 6, P gt; 0.05). The IA value of β-catenin in group C (6.611 7 ± 0.381 8) was lower than that in group B (11.799 9 ± 0.348 7) and higher than that in group A (4.390 3 ± 0.551 9), showing significant differences (P lt; 0.05). The mRNA expression of Col II in group C was significantly higher than those in groups A and B (P lt; 0.05), the mRNA expression of MMP-13 in group C was significantly lower than that in group B (P lt; 0.05) but there was no significant difference when compared with group A (P gt; 0.05). The mRNA expression of β-catenin in group C was significantly lower than that in group B (P lt; 0.05) and higher than that in group A (P lt; 0.05). Conclusion ALN can protect rat chondrocyte from OA induced by IL-1β in vitro possibly by upregulating Col II and inhibiting the expression of MMP-13 and β-catenin in the chondrocytes.
Objective To investigate the effect ofestrogen on osteoarthritis in female rats.Methods Forty female rats were divided into four groups. In group Ⅰ, the rats were not given any treatment as a control. Ingroups Ⅱ, Ⅲ and Ⅳ, the rats received fixing left knee joint on extension position. Meanwhile, therats received ovariectomy in group Ⅲ; ovariectomy and diethylstilbestrol treatment in group Ⅳ, respectively. After 4 weeks, histological observation and serum BGP examination were done.Results In groups Ⅱ, Ⅲ andⅣ, the levels of serum BGP were 3.50±0.39, 5.72±0.64 and 3.95±0.44, respectively. The pathologic grades of cartilage and synovium were 10.83±4.35 and 4.21±2.03; 15.32±3.42 and 7.62±3.42; and 12.65±2.73 and 5.46±1.23, respectively. Conclusion Estrogen may play an important role in delaying the development of osteoarthritis.
Objective To review the progress of mechanism of parathyroid hormone (PTH) and parathyroid hormone-related protein (PTHrP) on normal and osteoarthritis (OA) cartilage and subchondral bones. Methods Recent 1iterature about the effects of PTH and PTHrP on normal and OA cartilage was reviewed. Results PTH and PTHrP can repress the hypertrophic differentiation and apoptosis of chondrocytes and promote their prol iferation, which has a protection effect on chondrocytes of OA; osteoblasts from subchondral bone of OA show a decreased reaction to PTH. Conclusion PTHand PTHrP may delay and protect the progression of OA, which involves in regulating cartilage degeneration and subchondral bone remodl ing through many kinds of signal pathway.
Objective To review the recent research progress on relationshi p between subchondral bone and cartilage degeneration in osteoarthritis (OA), and to predict future research directions. Methods Recent l iteratures about the pathological changes of subchondral bone in OA were reviewed and analyzed in terms of biomechanics, bone remodel ingand biological factors. Results Subchondral bone sclerosis or softening was the result of osteoarthritis and also closely related to the occurrence and development of OA. Inhibiting the bone metabol ism of subchondral bone could slow the degeneration of articular cartilage. Conclusion For the treatment of OA, it is necessary to pay close attention to cartilage changes and the prevention of subchondral bone degeneration.
ObjectiveTo investigate the causal association between metabolic syndrome (MetS) components and osteoarthritis of the knee (KOA) by using Mendelian randomization analysis. MethodsThe genome-wide association study database (GWAS) was mined, in which the exposure factors were MetS components, namely waist circumference (WC) level, triglyceride (TG) level, high-density lipoprotein cholesterol (HDL-C) level, hypertension (HBP), and type 2 diabetes (T2DM), and the outcome factor was KOA. Mendelian randomization analysis was performed using regression models of inverse-variance weighted (IVW), MR-Egger, Simple Mode, Weighted Median, and Weighted Mode methods. ResultsIVW showed a causal relationship between WC level and KOA with a positive correlation (OR=3.088, 95%CI 2.574 to 3.704, P<0.01), and HDL-C level had a causal relationship with KOA with a negative correlation (OR=0.877, 95%CI 0.779 to 0.989, P<0.05). IVW did not show a causal relationship between TG levels, HBP, and T2DM with KOA (P>0.05). The results of the ME-Egger intercept test were not multiplicative (P>0.05), indicating that Mendelian randomization was a valid method for causal inference in this study. ConclusionCentral obesity and low HDL-C disorder are independent risk factors for KOA. The causal relationship between TG level, HBP, and T2DM with KOA is still uncertain.
Objective To review the effect of calcitonin on cartilage and subchondral bone of osteoarthritis. Methods Recent l iteratures about the effect of calcitonin on osteoarthritis was reviewed. Results Calcitonin could promotethe synthesis of important cartilage matrix such as proteoglycans and collagen II, propell ing the regeneration of cartilage and subchondral bone. Conclusion Calcitonin can protect articular cartilage through promoting the synthesis of cartilage and inhibiting its degradation.
Objective To analyze the outcomes and complications after total knee replacement(TKR) with posterior stabilized prosthesis(PS) and to investigate the influencing factors relating to outcomes. Methods From January 1998 to August2004, 60 cases (74 knees) of osteoarthritis underwent TKR with PS. The outcomeswere evaluated according to the HSS(hospital for special surgery) scoring. The difference in outcomes between patients with post-operative complications and without complications were compared. Pearson correlation was used to analyze post-operative outcomes and the pre-operative factors relating to patients. Results All 74 knees werefollowed up 42.5months(24 to 94 months). The scores for HSS, pain, function, ROM muscle strength, flexion deformity and stability of knees after operation were 84.2±14.2, 25.7±6.9, 17.9±4.3,13.1±2.0，9.2±0.8，8.1±0.4 and 9.3±0.1 respectively. They were improved to some extents, especially pain alleviation was remarkable. The excellent and good rate for outcome assessment was 90.5%. Among 74 knees, 10 cases suffered from postoperative complications, including 1 case of common peroneal nerve paralysis, two cases of wound faulty union, one case of wound infection, one case of joint infection, one case of stiff knee, two cases of deep vein thrombosis and 2 cases of patellofemoral joint complications. The excellent and good rate of outcome in patients with complications(60%) was much lower than that in patients without complication(95.3％),and there was significant difference betweenthem (P＜0.05). Analysis for correlation showed that postoperative HSS score was positively correlative with the postoperative HSS score, pain and function score of knees. The correlation value was 0.523，0.431 and 0.418 respectively(Plt;0.01). Whereas, postoperative HSS score was not correlative with ROM, muscle strength, flexion deformity, stability of knee, age, weight andbody mass index(P＞0.05). Conclusion TKR with PS is an effective method for severe osteoarthritis. The outcomes after TKR have a positive correlation with the HSS score, pain and function score of knees before surgery. Complicationsassociating with surgery have a negative influence on outcomes.
ObjectiveTo systematically evaluate the efficacy and safety of intra-articular injection of hyaluronic acid for knee osteoarthritis. MethodsDatabases including PubMed, EMbase, The Cochrane Library (Issue 1, 2016), WanFang Data, CBM, and CNKI were searched to collect randomized controlled trials (RCTs) about intra-articular injection of hyaluronic acid for knee osteoarthritis from inception to February 2016. The meta-analysis was conducted using RevMan 5.3 software. ResultsA total of 17 RCTs involving 4 070 patients were included. The results of metaanalysis showed that: there were no significant differences in WOMAC pain scores (7 weeks: MD=-0.01, 95%CI -0.46 to 0.44, P=0.98; 13 weeks: MD=-0.01, 95%CI -0.46to 0.43, P=0.95; 26 weeks: MD=0.32, 95%CI -0.04 to 0.67, P=0.08), stiffness scores (7 weeks: MD=0.10, 95%CI -0.26 to 0.45, P=0.59; 13 weeks: MD=0.24, 95%CI -0.11 to 0.60, P=0.17; 26 weeks: MD=0.06, 95%CI -0.09 to 0.22, P=0.42), and life function scores (7 weeks: MD=-0.20, 95%CI -0.75to 0.36, P=0.49; 13 weeks: MD=-0.02, 95%CI -0.57 to 0.52, P=0.93; 26 weeks: MD=0.30, 95%CI -0.07 to 0.67, P=0.11) between the hyaluronic acid group and the control group in 7-, 13- and 26 weeks. However, the hyaluronic acid group was superior to the control group in 50-step test (MD=-0.49，95%CI -7.36 to -3.61，P<0.000 01). ConclusionCurrent evidence suggests that intra-articular injection of hyaluronic acid has better effect than control treatment for pain at movement. However, due to the limited quantity of the included studies, the above conclusion still need to be verified by more high quality studies．
A micro silicone oil liquid spring was designed and manufactured in this article. The performance of the liquid spring was studied by simulation analysis and mechanical test. A self-force source power-assisted knee orthosis was designed based on the liquid spring. This power-assisted knee orthosis can convert the kinetic energy of knee flexion into the elastic potential energy of liquid spring for storage, and release elastic potential energy to generate assisted torque which drives the knee joint for extension. The results showed that the average maximum reset force of the liquid spring was 1 240 N, and the average maximum assisted torque for the knee joint was 29.8 N·m. A musculoskeletal multibody dynamic model was used to analyze the biomechanical effect of the knee orthosis on the joint during knee bending (90°knee flexion). The results showed that the power-assisted knee orthosis could effectively reduce the biomechanical load of the knee joint for the user with a body weight of 80 kg. The maximum forces of the femoral-tibial joint force, patellar-femoral joint force, and quadriceps-ligament force were reduced by 24.5%, 23.8%, and 21.2%, respectively. The power-assisted knee orthosis designed in this article provides sufficient assisted torque for the knee joint. It lays a foundation for the subsequent commercial application due to its small size and lightweight.