Corresponding Changes of Autophagy-Related Genes and Proteins in Different Stages of Knee Osteoarthritis: An Animal Model Study.

OBJECTIVE: To investigate the effect of autophagy expression levels of different weight-bearing states and different stages of osteoarthritis in animal models, as well as the corresponding mechanisms. METHODS: We used the male Sprague-Dawley (SD) rats (12-week-old, SPF) to establish the OA animal models by modified Hulth method, and grouped animal models according to the length of time after surgery and different weight-bearing areas. RT-qPCR was carried out for detection of autophagy-related genes such as Atg7, Atg12, P62, etc. Western blot analysis was used to detect the expression levels of corresponding autophagy-related proteins such as LC3B, P62, etc. T test was performed for statistical analysis to compare different groups, while the differences were deemed statistically significant with P < 0.05. Transmission electron microscopy was used to observe the autophagosome to demonstrate the level of autophagy expression and the status of the chondrocytes. RESULTS: The results of the RT-qPCR testing showed that when the weight-bearing cartilage of the 4-week group (relatively mild) was compared with that of the 10-week group (relatively severe), there were statistically significant differences in all the genes tested, in detail: Atg3 (P < 0.01), Atg7 (P < 0.01), Atg12 (P < 0.01), P62 (P < 0.0001). The expression of autophagy-related mRNA in the 4-week group is increased compared with that of the 10-week group. As for the expression of proteins, Western blotting showed that in the comparison between the 4- and the 10-week groups, statistically significant results include Atg12 (P < 0.01) in the non-weight-bearing area, with decreased autophagy in the 10-week group compared with that of the 4-week group, while expression of LC3B (P < 0.05) protein was significantly higher in the 4-week group than in the control in the non-weight-bearing area. The expression of LC3B (P < 0.0001) and P62 (P < 0.05) in the 10-week group were higher than that of the control. Transmission electron microscope showed that autophagy in the weight-bearing area is stronger than that in the non-weight-bearing area, and autophagy in the 4-week group is stronger than in the 10-week group for the weight-bearing area. CONCLUSIONS: The expression of autophagy varies during different stages of osteoarthritis, in which the autophagy is stronger in the early stage of osteoarthritis, and gradually decreases with the progression of the disease. Autophagy in different weight-bearing areas may also be different.

Destination Joint Spacers: A Similar Infection-Relief Rate But Higher Complication Rate Compared with Two-Stage Revision.

OBJECTIVE: To evaluated the clinical outcomes of periprosthetic joint infection (PJI) patients with destination joint spacer compared with that of two-stage revision. METHODS: From January 2006 to December 2017, data of PJI patients who underwent implantation with antibiotic-impregnated cement spacers in our center due to chronic PJI were collected retrospectively. The diagnosis of PJI was based on the American Society for Musculoskeletal Infection (MSIS) criteria for PJI. One of the following must be met for diagnosis of PJI: a sinus tract communicating with the prosthesis; a pathogenis isolated by culture from two separate tissue or fluid samples obtained from the affected prosthetic joint; four of the following six criteria exist: (i) elevated ESR and CRP; (ii) elevate dsynovial fluid white blood cell (WBC) count; (iii) elevated synovial fluid neutrophil percentage (PMN%); (iv) presence of purulence in the affected joint; (v) isolation of a microorganism in one periprosthetic tissue or fluid culture; (vi) more than five neutrophilsper high-power fields in five high-power fields observed from histological analysis of periprosthetic tissue at ×400 magnification. Age, sex, body mass index (BMI), and laboratory test results were recorded. All patients were followed up regularly after surgery, the infection-relief rates were recorded, Harris hip score (HHS) and knee society score (KSS) were used for functional evaluation, a Doppler ultrasonography of the lower limb veins was performed for complication evaluation. The infection-relief rates and complications were compared between destination joint spacer group and two-stage revision group. RESULTS: A total of 62 patients who were diagnosed with chronic PJI were enrolled, with an age of 65.13 ± 9.94 (39-88) years. There were 21 cases in the destination joint spacer group and 41 cases in the temporary spacer group, namely, two-stage revision group (reimplantation of prosthesis after infection relief). The Charlson comorbidity index (CCI) in the destination joint spacer group was higher than that in the temporary spacer group, and this might be the primary reason for joint spacer retainment. As for infection-relief rate, there were three cases of recurrent infection (14.29%) in the destination joint spacer group and four cases of recurrent infection (9.76%) in the two-stage revision group, there were no significant differences with regard to infection-relief rate. Moreover, there two patients who suffered from spacer fractures, three cases of dislocation, one case of a periarticular fracture, and three cases of deep venous thrombosis in destination joint spacer group, while there was only one case of periprosthetic hip joint fracture, one case of dislocation, and one patient suffered from deep venous thrombosis of the lower extremity in two-stage revision. The incidence of complications in the destination joint spacer group was higher than that of two-stage revision. CONCLUSIONS: In summary, the present work showed that a destination joint spacer might be provided as a last resort for certain PJI patients due to similar infection-relief rate compared with two-stage revision.

Plant homeodomain finger protein 23 inhibits autophagy and promotes apoptosis of chondrocytes in osteoarthritis.

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-1ß (IL-1ß). IL-1ß 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-1ß-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-1ß-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-1ß-induced OA-like chondrocytes. CONCLUSIONS: The expression of PHF23 increased in human OA cartilage and synovium, and was induced by IL-1ß through inflammatory stress. PHF23 can suppress autophagy of chondrocytes, and accelerate apoptosis.

Effects of Tumor Necrosis Factor Alpha on the Expression of Programmed Cell Death Factor 5 in Arthritis.

OBJECTIVE: To investigate the effect of tumor necrosis factor alpha (TNF-α) on the proliferation of fibroblast-like synoviocytes (FLS) and the expression of programmed cell death factor 5 (PDCD5) in an inflammatory microenvironment, for the further understanding of the mechanism of action of TNF-α in promoting the proliferation of synovial cells and the apoptosis of the chondrocytes. METHODS: Articular carriage specimens were obtained from 21 cases with osteoarthritis and 12 cases with femoral neck fractures as healthy controls during arthroplasties. The expression of PDCD5 was evaluated by immunofluorescence analyzed by mean option density (MOD) detected using the software ImagePro Plus. Real-time PCR was performed to evaluate the transcriptions of PDCD5 and TNF-α in synovium. FLS cells derived from rheumatoid arthritis patients were cultured in vitro and incubated with different concentrations of TNF-α. The effects of TNF-α at different concentrations on the proliferation of FLS cells were detected by Cell Counting Kit-8 (CCK-8) assay to evaluate the cell proliferation rate. After incubation with the absence or presence of recombinant human TNF-α at different concentrations, the FLS cells were isolated for detection of PDCD5 protein and PDCD5 gene. The expression of PDCD5 protein was detected by western-blot and the transcription of PDCD5 gene from the cells was detected by real-time quantitative PCR. RESULTS: The MOD of PDCD5 as well as TNF-α of osteoarthritis cartilage sections were significantly increased compared with those of the controls, and in synovium there was a positive correlation between transcriptions of their mRNA. When the concentration of TNF-α was 1 ng/mL, the cell proliferation rate was not significantly different from that of the control group (P = 0.592), while the proliferation of FLS cells was significantly promoted when the concentration of TNF-α was 5, 10, 15, or 20 ng/mL, and the proliferation-promoting rates were 35.64% ± 6.96%, 48.72% ± 7.69%, 45.60% ± 8.85%, and 39.32% ± 6.18%, respectively (P < 0.01). The transcription of PDCD5 gene was significantly downregulated, which was 80.44% ± 4.07% and 84.30% ± 5.48%, respectively (P < 0.05), in the FLS cells incubated with TNF-α at the concentration of 10 and 15 ng/mL for 24 h. When the concentration of TNF-α was 1, 5, or 20 ng/mL, the transcription of PDCD5 mRNA in FLS cells was not significantly different from that in the control group (P > 0.05). The expression of PDCD5 protein was only significantly downregulated when the concentration of TNF-α was 10 ng/mL (P < 0.01), while the expression of PDCD5 protein in FLS cells was not significantly different from that in the control group (P > 0.05). CONCLUSION: The expression of PDCD5 as well as TNF-α in osteoarthritis cartilage and synovium was significantly higher than in healthy tissues, and TNF-α can promote the proliferation of FLS cells in patients with rheumatoid arthritis, and inhibit the expression of PDCD5. PDCD5 may be involved in the abnormal proliferation of synoviocytes and the degeneration of chondrocytes stimulated by TNF-α.

Programmed cell death 5 correlates with disease activity and interleukin-17 in serum and synovial fluid of rheumatoid arthritis patients.

BACKGROUND: Programmed cell death 5 (PDCD5) is a novel apoptotic regulatory gene that promotes apoptosis in various tumor cells. Studies have shown that PDCD5 accelerates the apoptosis of synoviocytes in vitro, implying a potential role in rheumatoid arthritis (RA) pathogenesis. This study examined the expression of PDCD5 in serum and synovial fluid of RA patients, its effect on the expression of inflammatory cytokine, interleukin-17 (IL-17), and the assessment of disease activity in RA. METHODS: PDCD5 and IL-17 levels in serum and synovial fluid from 18 patients with RA and 22 patients with osteoarthritis (OA) were detected using enzyme-linked immunosorbent assay (ELISA). Concentrations of serum PDCD5 in 40 healthy people were also detected as controls. As disease activity indices, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), rheumatoid factor (RF), and X-ray grading scale were also evaluated. RESULTS: Serum and synovial fluid PDCD5 levels in RA patients were significantly higher than those in OA and healthy controls. Serum PDCD5 level was inversely correlated to CRP and ESR, and was significantly higher in the RF negative group than in the positive group. PDCD5 level was also negatively correlated with IL-17 levels both in serum and synovial fluid of RA patients. However, differences in synovial fluid PDCD5 level from RA patients at different Larsen stages were not detectable. CONCLUSIONS: PDCD5 affects RA pathogenesis. Insufficient apoptosis of fibroblast-like synoviocytes and inflammatory cells in RA could increase the expression of PDCD5 protein. As PDCD5 levels correlated negatively with disease activity indices and IL-17 level, PDCD5 could become a target in the diagnosis and treatment of RA.

[Autogeneous bone graft in the treatment of total knee arthroplasty for severe genu varus with tibial plateau bone defect].

OBJECTIVE: To introduce the method and experience of autogeneous bone graft for tibial plateau reconstruction during the procedure of total knee arthroplasty for severe varus knees with bone defect in the medial tibial plateau. METHODS: From April 2007 to March 2011, 19 knees of 16 osteoarthritic patients who had serious genu varus with bone defect in medial tibial plateau underwent primary total knee arthroplasty, their mean varus degree being 32° (25°to 45°), and average age 66±8 years (52 to 77 years). Their preoperative knee functions are as follows: the average range of motion (ROM) was 62°(37° to 90°); average knee society scure(KSS) knee score was 18 points (-24 to 41 points); average function score was 13 points (-21 to 43 points). During operation, the slope bone defect of the medial tibial plateau was dressed into step-shape horizontal bone defect by osteotomy, and then the defect was restored with the resected tibial plateau autograft whose thickness and shape were matched in advance; and the high-intensity cortical part of the autograft was placed on the rim, to sustain the tibial prosthesis; and a lateral pressure from the rim had to be maintained to the autograft until the cement under tibial prosthesis solidified. The long-stem tibial prostheses were used in 3 patients ( 3 knees ). All knee prostheses were fixed using antibiotic bone cements. RESULTS: The average follow-up after TKR was 25 months (3 to 50 months), the average ROM was 112° (95° to 125°); average KSS score 86 points (71 to 93 points), and knee function score 88 points ( 74 to 96 points). The nonunion, shift, fracture of the autologous graft bone were not found; no tibial prosthesis became loose, either; no knee was revised for delayed infection or recurrent varus due to autologous graft bone absorption. CONCLUSION: In TKA for severe varus osteoarthritic patients with bone defect in the tibial plateau, there are various ways to regain its stability, and reconstruction is adopted by using step-shape allograft in this paper. This method can not only restore the integrity of the tibial plateau, providing good initial stability of the prostheses, and exempting from internal fixations, but also offer more reliable compatibility than other methods, reducing postoperative infection rates, and obtaining satisfied initial curative effect.

[Study about outcomes of non-pharmacological conservative treatment for lumbar spinal stenosis].

OBJECTIVE: To describe the short-term outcomes of a non-pharmacological conservative approach to patients with LSS. METHODS: This is a prospective consecutive case series with short-term follow-up of 21 consecutive patients who were diagnosed with LSS. Patients recruited from the outpatients of orthopaedic department and rehabilitation department in the Peking University People's Hospital from March 2010 to March 2011. Patients had baseline interviews with follow-up questionnaires in the end of the first and the third month. MAIN OUTCOME MEASURES: pain intensity was measured using the Numerical Rating Scale (NRS) and disability was measured using the Roland Morris Disability Questionnaire (RMDQ), as well as the 36-item Short Form Health Surrey (SF-36) and efficacy assessment for evaluation. RESULTS: All of 21 eligible consenting patients initially enrolling completed the follow-up. Pain at worst, functional status, quality of life improved significantly in the end of the first month. These were considered to be clinically meaningful in the end of the third month. No patients went on to require surgery. No major complications of treatment were noted. CONCLUSIONS: A non-pharmacological conservative treatment may be useful and safe in bringing about clinically meaningful improvement in pain and disability in patients with LSS. Before surgical management, a non-surgical approach should be taken into account at first.

[Aggrecanases and osteoarthritis].

Osteoarthritis is mainly caused by the degenerative changes of cartilage and cartilage extracellular matrix, while Aggrecanases degradate Proteoglycans which are the major components of cartilage. This review includes three aspects: (1) We have concluded the major enzymes(ADAMTS-4 and ADAMTS-5) which regulate the metabolism of cartilage extracellular matrix. Meanwhile, we have summarized the structure of aggrecanases(ADAMTS-4 and ADAMTS-5) and introduced the function of each regional structure; (2) We have concluded the way cytokines and glycosaminoglycans regulate the metabolism of aggrecanases, and discussed the regulation and control principle of cytokines and glycosaminoglycan; (3) We have summarized the majority of inhibitors to the aggrecanases, introduced the endogenic inhibitors, and put our emphasis on the extrinsic inhibitors (chelating agents, polypeptides and so on). Through deeper research on the enzymes, it will help us further understand the pathogenesis of osteoarthritis, and open up new avenues to clinical treatment.

[Correlation between single nucleotide polymorphism of prothrombin gene G20210 and deep vein thrombosis after total joint replacement].

OBJECTIVE: To evaluate the correlation between prothrombin gene G20210A mutation and deep vein thrombosis after total joint replacement through detecting distribution frequency of single nucleotide polymorphism of the gene in patients undergoing total joint replacement. METHOD: PCR and direct sequencing of DNA are used to analyze the frequency of prothrombin gene G20210A mutation in 55 patients undergoing total joint replacement, and the relationship between the mutation and deep vein thrombosis after total joint replacement is evaluated. RESULT: Morbidity of prothrombin gene G20210A mutation in 55 patients is 0, both in either DVT group (27 patients) or non-DVT group (28 patients). There is no significant difference between the two groups (P>0.05). CONCLUSION: Mutation of prothrombin gene G20210A in Chinese patients is rare, and there is no correlation between the genetic mutation and deep vein thrombosis after total joint replacement.

Research on coagulation of unwashed shed blood after total knee replacement in Chinese patients.

To evaluate quality of unwashed but filtered wound shed blood through ConstaVac blood conservation system (Stryker Company) after total knee replacement, we selected 30 patients who underwent total knee replacement consecutively from July 2003 to July 2004 and received retransfusion of wound shed blood. Pre- and postoperative coagulative factors of peripheral vein blood and wound shed blood were measured, such as fibrinogen, AT-III, D-dimer, plasminogen, and PT, APTT were also measured. No clinical evidence of coagulation and DIC appeared in these patients. There is significant change of coagulative factors in unwashed but filtered wound shed blood and it may cause a potential risk of coagulopathy to retransfuse wound shed blood, but retransfusion of unwashed but filtered shed blood appeared to be relative safe clinically.

[Total knee arthroplasty and perioperative management of hemophilic arthritis].

OBJECTIVE: To evaluate the clinical results and perioperative management of primary total knee arthroplasty (TKA) in hemophilic patients. METHODS: From February 1997 to February 2006, the data of 6 total knee arthroplasty performed in 4 hemophilic patients was reviewed retrospectively. The values of coagulation factor were maintained at suitable level by monitoring the activity of the factors and their inhibitors during perioperative period. The mean follow-up time was 4.4 years, knee society score and the last postoperative radiographs were recorded. RESULTS: After TKA, the hemophilic patients felt pain of knee relieved, the knee function was improved, but the range of motion increased limitedly. At the early post-operative stage, 3 knees in 2 patients with hemarthrosis or muscle bleeding, 1 of the 2 patients complicated with formation of inhibitor of factor VIII and healing problem in 1 knee after TKA, 1 patient with transient paralysis of the common peroneal nerve, 1 patient with venous circulation insufficiency crisis, but no compartment syndrome. In the late stage after TKA, 1 patient with hemarthrosis of both elbows, but no late infection, loosening, displacement and fracture of the prosthesis in the 6 knees. CONCLUSIONS: Total knee arthroplasty could alleviate knee pain and improve joint function in advanced severe hemophilic arthritic patients. It is important to monitor the activity and inhibitors of coagulation factor VIII or IX, which could decrease the early and late postoperative complications.

[Total knee arthroplasty for extension ankylosing deformity].

OBJECTIVE: To discuss the outcomes and complications of total knee arthroplasty (TKA) for extension ankylosing deformity of the knee. METHODS: From January 1996 to June 2006, total knee arthroplasty was performed on 8 patients (9 knees) with extension ankylosing deformity. The preoperative ROM of all patients was 0 degrees . Preoperative knee and function score of KSS were 44 points (from 10 to 68) and 17 points (from -10 to 55) respectively. RESULTS: The complications of all TKAs included patellar tendon avulsion in 1 knee, partial fracture of inferior patella in 1 knee, hematoma in 1, superficial infection in 1. All patients were followed up for an average of 40.4 months (from 7.0 to 120.0). The average postoperative ROM was 89 degrees (from 50 degrees to 120 degrees ). Postoperative knee and function score of KSS were 81 points (from 55 to 93) and 79 points (from 50 to 90) respectively. Extension lag occurred in 2 knees, one was 10 degrees and the other was 25 degrees . One knee had undergone re-revision of changing the thicker tibial spacer for the reason of instability of joint 1 year after revision. CONCLUSIONS: TKA performed in extension ankylosing deformity can get less satisfactory clinical results comparing with fixed flexion deformity. Exposure of the knee joint and separation of the fused bones, providing a mobile joint space plays crucial procedure for the next step of surgery. Preservation of sufficient bone stock of patella, protection of patellar tendon and blood supply of the knee and proper soft tissue balance are the key to TKA for extension ankylosing deformity.

Involvement of PDCD5 in the regulation of apoptosis in fibroblast-like synoviocytes of rheumatoid arthritis.

Apoptosis is reduced in the synovial tissue of patients with rheumatoid arthritis (RA), possibly due to decreased expression of pro-apoptotic genes. Programmed Cell Death 5 (PDCD5) has been recently identified as a protein that mediates apoptosis. Although PDCD5 is down-regulated in many human tumors, the role of PDCD5 in RA has not been investigated. Here we report that reduced levels of PDCD5 mRNA and protein are detected in RA synovial tissue (ST) and fibroblast-like synoviocytes (FLS) than in tissue and cells from patients with osteoarthritis (OA). We also report differences in the PDCD5 expression pattern in tissues from patients with these two types of arthritis. PDCD5 showed a scattered pattern in rheumatoid synovium compared with OA, in which the protein labeling was stronger in the synovial lining layer than in the sublining. We also observed increased expression and nuclear translocation of PDCD5 in RA patient-derived FLS undergoing apoptosis. Finally, overexpression of PDCD5 led to enhanced apoptosis and activation of caspase-3 in triptolide-treated FLS. We propose that PDCD5 may be involved in the pathogenesis of RA. These data also suggest that PDCD5 may serve as a therapeutic target to enhance sensitivity to antirheumatic drug-induced apoptosis in RA.

[Influence of preoperative range of motion on the early clinical outcome of total knee arthroplasty].

OBJECTIVE: To retrospectively analyze the influence of preoperative range of motion (ROM) and maximal flexion degree on the early clinical outcome of total knee arthroplasty (TKA). METHODS: From January 2000 to December 2003, 97 knees of 65 patients that were underwent total knee arthroplasty with Scorpio posterior-stabilized knee prosthesis were reviewed. There were 55 osteoarthritis patients (81 knees), and 10 rheumatoid arthritis (16 knees). Thirty-three patients were underwent unilateral TKA, 32 patients were underwent bilateral TKA. According to the preoperative ROM of knee, these patients were divided into two groups, one 90 degrees (range, 95 degrees - 140 degrees ). Finally the clinical outcomes of two groups (include ROM, maximal flexion degree, KSS score and function score) were evaluated. Three days later after operation, continuous passive motion (CPM) and active functional exercise of the knee were begun, and the wound healed well in all patients. All these operations were primary total knee arthroplasty. RESULTS: The patients were followed up for average 2 years 5 months (range, 10 months to 3 years 8 months). The average ROM of knee was improved to 101.6 degrees (range, 40 degrees - 140 degrees ) after operation from 84.2 degrees (range, 5 degrees - 140 degrees ) before operation (P = 0.000); the average maximal flexion degree was decreased from 103.5 degrees (range, 25 degrees - 140 degrees ) before operation to 101.6 degrees (range, 40 degrees - 140 degrees ) after operation (P = 0.439); KSS of knee joint was improved to 78.8 points after operation (range, 50 - 95 points) from 19.5 points (-24 - 62 points) before operation (P = 0.000). There was statistically difference between the clinical outcomes (ROM, maximal flexion degree, KSS score and function score) in the two groups before and after operation. Those knees with good preoperative ROM tend to lose flexion, while those with poor preoperative ROM gain flexion after TKA. No revision and deep infection happened. CONCLUSIONS: TKA is a complex operation, the clinical outcome of TKA is mainly determined by the good operation skill, abundant clinical experience and the familiarity with the prosthesis of the surgeon. At the same conditions such as same surgeon, same prosthesis and same physical therapy, preoperative range of motion of knee influence on the early clinical outcome of total knee arthroplasty, knees that have good preoperative ROM have better clinical outcomes postoperatively than those with poor preoperative ROM.

[Total knee replacement in valgus knee].

OBJECTIVE: To investigate the methods and clinical results of total knee replacement (TKA) in patients with valgus knee deformity. METHODS: Between January 1996 and August 2004, 87 TKAs were performed by means of medial parapatellar approach, standard osteotomy and only lateral soft tissue release with posterior stabilized implants on 74 patients (11 men and 63 women) with valgus deformity. The average age at the time of operation was 62.93 years (range, 26-80 years). Clinical and radiographic evaluations including range of motion (ROM), Knee Society Score System (KSS) and the tibial and femur angle (T-F angle) were performed at follow-up. RESULTS: After a mean follow-up of 33.8 months (range, 5 months-9 years), the average ROM improved from 91 degrees (range, 70 degrees-120 degrees) preoperatively to 112.4 degrees (range, 80 degrees-130 degrees) postoperatively, the average KSS improved from 22.7 points (0-48 points) preoperatively to 81.7 points (range, 71-93 points) postoperatively. The average function score improved from 26.5 points preoperatively to 86.3 points postoperatively, the average T-F angle was corrected from 21.59 degrees (range, 12 degrees-40 degrees) of valgus preoperatively to 8.7 degrees (0 degrees-11 degrees) of valgus postoperatively. One knee had lightly instability at follow-up, one knee with patellar dislocation preoperatively had subdislocation postoperatively, no other complication occurred. CONCLUSIONS: The techniques of medial parapatellar approach, standard osteotomy and only lateral soft tissue release with posterior stabilized implants can correct a fixed valgus deformity very successfully in patients undergoing primary total knee replacement, and provides excellent results.

[Clinical risk factors for deep vein thrombosis after total hip and knee arthroplasty].

OBJECTIVE: To analyze the clinical risk factors for deep vein thrombosis (DVT) after total hip and knee arthroplasty in Chinese patients who received prophylactic treatment for DVT. METHODS: We evaluated 128 total hip arthroplasty (THA) and total knee arthroplasty (TKA) in 95 patients performed at our center from April 2004 to August 2004, which included 48 THAs in 43 patients and 80 TKAs in 52 patients. There were 27 men and 68 women with a mean age of 59.77 years (range, 23-78 years). All patients had been given low-molecular-weight heparin before operation and for 7-10 days post-operation to prevent DVT. Color Doppler ultrasonography was used to detect DVT of bilateral lower extremities in all patients before operation and at 7-10 days after operation. Nineteen clinical factors were examined preoperation and 7-10 days post-operation in order to analyze their influences on DVT formation after surgery. RESULTS: There were 45 patients who developed DVT after operation. The incidence of DVT in all patients was 47.4% (45/95) and the incidence of proximal DVT was 3.2%. There were more asymptomatic DVT (57.8%, 26/45) than symptomatic ones, and some patients without DVT (14%, 7/50) presented some of the DVT symptoms. Logistic regression analysis demonstrated a definite association of female, obesity (representative by BMI), cement usage and diagnosed RA with DVT with odds ratio of 10.008, 3.094, 8.887, and 0.194 respectively. Other clinical factors had no statistically significant association with DVT. CONCLUSIONS: Female, obesity, and cement usage were the risk factors for DVT after THA and TKA, and diagnosed RA was the protecting factors for DVT after THA and TKA. Other clinical factors such as age, OA, type of implant, monolateral or bilateral operation, duration of anesthesia, surgery and bandage usage for blood control, time for immobilization et al were not the risk factors for DVT.

[Revision hip arthroplasty with the cementless prosthesis: 4 years follow-up study].

OBJECTIVE: To examine the two to eight-year results associated with the use of this hip system. METHODS: Between November 1996 and January 2001, 56 revision total hip arthroplasties with insertion of a Zweymüller BICON-PLUS cup and a cementless SLR-PLUS stem were performed in 55 consecutive patients (average age, fifty-nine years old, range, thirty to eighty years old). RESULTS: At the time of the latest follow-up, 23 patients (24 hips) had lost to follow-up, leaving 32 patients for a minimum of 2 years of clinical and radiographical follow-up. The mean follow-up time was 4 years. Only 3 peri-operative complications occurred, including 1 great trochanter fracture during implant removal, 1 dislocation 2 d after operation with successful closed reduction, and 1 deep wound infection which necessitated reentry and debridement. No femoral stems or cups needed re-revision surgery. The average Harris hip score increased from 40.6 points preoperatively to 80.4 points at final follow-up. Radiographic analysis demonstrated that the position of stems and cups was unchanged and all showed radiographic evidence of bone ingrowth. CONCLUSION: The favourable medium-term clinical results with the cementless Zweymüller hip system show that it is suitable as a revision system for total hip failures of both cemented and cementless primary fixation.

[Early diagnosis and treatment of pulmonary embolism after total joint replacement: report of five cases].

OBJECTIVE: To study the early diagnosis and treatment of pulmonary embolism (PE) after total joint replacement (TJR). METHODS: >From April 1987 to December 2001, we performed 1,336 total knee replacements (TKR(s)) in 926 patients and 1,745 total hip replacements (THR(s)) in 1,566 patients. In this group there were 5 PE patients after operation. Two patients died (all after TKR), and 3 patients salvaged successfully (2 after TKR, 1 after THR). RESULTS: The total incidence of PE after TJR was 0.2% (5/2,492), the incidence of PE after TKR was 0.4% (4/926), and the incidence of PE after THR was 0.06% (1/1,556). In the patients who suffered PE, 2 died. The incidence of PE before 2000 was 0%. CONCLUSIONS: Death after total joint replacement is due to pulmonary embolism (PE), especially massive PE. The incidence of PE after TKR is higher than that after THR. Pulmonary angiography is the gold standard for the diagnosis of PE. With more understanding on PE and more popularity of joint replacement, the diagnosis of PE after TJR is increased. More attention should be paid to PE in the patients with high risk after TJR.