High failure rate after Beta-tricalcium phosphate grafting for the treatment of femoral head osteonecrosis: a retrospective analysis.

BACKGROUND: Non-vascularized bone grafting is a promising head-preserving technique for younger patients diagnosed as non-traumatic osteonecrosis of the femoral head (NONFH). Among the various types of bone grafting techniques, "light-bulb" procedure grafting with synthetic bone substitute is an attractive option. We aimed to assess the effectiveness of using beta-tricalcium phosphate (ß-TCP) for the treatment of pre-collapse and early post-collapse lesions NONFH. METHODS: From April 2010 to June 2014, 33 patients (47 hips) with NONFH were treated using the afore-mentioned technique. The clinical and radiological outcomes were recorded and compared statistically between pre- and post-operation. Harris hip score (HHS) was used to evaluate the clinical results, and Association Research Circulation Osseous (ARCO) stage was applied to assess the radiological outcomes. RESULTS: The 5-years survival rate of using ß-TCP grafting was accounting for 25.5%. HHS was decreased from 78.47 to 52.87 points, and a very significant worsening of radiological results were revealed (P <  0.05). Two hips collapsed more than 2 mm were awaiting for THA, and 33 of the 47 hips had converted to THAs in an average time to failure of 24.24 months postoperatively. Meanwhile, only 4 hips survived without collapse, and 8 hips collapsed less than 2 mm. After surgery, the time onset of head collapse was 3.65 months on average, and the first conversion to THA was performed at 5 months postoperative. CONCLUSIONS: Our results suggest that "light-bulb" procedure grafting with ß-TCP sticks presented with a high failure rate in the early postoperative period. It is not proposed for the treatment of pre-collapse and early post-collapse lesions NONFH.

Quality of sexual life after total hip arthroplasty in male patients with osteonecrosis of femoral head.

BACKGROUND: Patients with osteonecrosis of the femoral head (ONFH) have a severe impact on their health status, functionality and quality of life. Sexual life is an important component of the quality of life and is still a frequently neglected domain in patients with ONFH. The aims of the study were to evaluate the influence of the disease and the total hip arthroplasty (THA) surgery on quality of sexual life (QSL) in these patients. METHODS: A prospective, self-controlled study was done. 247 patients of ONFH who underwent unilateral or bilateral THA were asked to complete a standardized QSL questionnaire, and the score of QSL was evaluated preoperatively and at first year follow-up of post-THA operation. RESULTS: The mean age of the patient was 46.8 (range 25-60) years. 194 cases (78.5%, 276 hips) were alcohol-induced ONFH. There is significant decrease (p = 0.026) in sexual relationship impairment on the 0-8 scale from pre-THA (5.3 ± 0.7) to post-THA (2.3 ± 0.4). There is no significant difference for effect on sexual function (p = 0.14) between pre-THA (2.3 ± 0.4) and post-THA (1.8 ± 0.3). There is significant improvement (p = 0.018) in overall sexual satisfaction degree of patients on the 1-5 scale from pre-THA (2.7 ± 0.2) to post-THA (4.7 ± 0.6), but no significant increase for sexual partner. CONCLUSION: ONFH has impaired relationships with partner and overall sexual satisfaction degree of the male patients; THA has improved significantly relationships with partner and overall sexual satisfaction degree of the male patients, but no effect on sexual function of the patients and overall sexual satisfaction degree of sexual partner.

[Effects of posterior tibial slope on non-contact anterior cruciate ligament rupture and stability of anterior cruciate ligament rupture knee].

OBJECTIVE: To retrospectively explore the correlation between anterior cruciate ligament (ACL)-ruptured knees, stability of ACL-rupture knee and posterior tibial slope (PTS). METHODS: From January 2008 to October 2012, 150 knees with ACL rupture underwent arthroscopic surgery for ACL reconstruction. A control group was established for subjects undergoing arthroscopic surgery without ACL rupture during the same period. PTS was measured on a digitalized lateral radiograph. Lachman and mechanized pivot shift tests were performed for assessing the stability of knee. RESULTS: There was significant difference (P = 0.007) in PTS angle between the patients with ACL rupture (9.5 ± 2.2 degrees) and the control group (6.6 ± 1.8 degrees). Only among females, increased slope of tibial plateau had effect on the Lachman test. There was a higher positive rate of pivot shift test in patients of increased posterior slope in the ACL rupture group. CONCLUSION: Increased posterior tibial slope (>6.6) appears to contribute to non-contact ACL injuries in females. And the changes of tibial slope have no effect upon the Lachman test. However, large changes in tibial slope affect pivot shift.

Pneumocystis jiroveci pneumonia after total hip arthroplasty in a dermatomyositis patient: A case report.

BACKGROUND: Pneumocystis jiroveci pneumonia (PJP) is a serious opportunistic infection that occurs mostly in patients with immunodeficiency and long-term immunosuppressive therapy. In non-human immunodeficiency virus-infected patients, the most important risk factor for PJP is the use of glucocorticoids in combination with other immunosuppressive treatments. The management of glucocorticoids during the perioperative period in patients with dermatomyositis requires special care. CASE SUMMARY: We report a case of PJP in the perioperative period. A 61-year-old woman with a history of anti-melanoma differentiation-associated gene 5 (MDA5)-positive dermatomyositis and interstitial pneumonia was administered with long-term oral methylprednisolone and cyclosporine. The patient underwent right total hip arthroplasty in the orthopaedic department for bilateral osteonecrosis of the femoral head. She was given intravenous drip hydrocortisone before anesthesia and on the first day after surgery and resumed oral methylprednisolone on the second postoperative day. On the fifth day after surgery, the patient suddenly developed dyspnea. The computed tomography scan showed diffuse grid shadows and ground glass shadows in both lungs. Polymerase chain reaction testing of bronchoalveolar lavage fluid was positive for Pneumocystis jiroveci. The patient was eventually diagnosed with PJP and was administered with oral trimethoprim-sulfamethoxazole. At the 6-mo review, there was no recurrence or progression. CONCLUSION: Continued perioperative glucocorticoid use in patients with anti-MDA5-positive dermatomyositis may increase the risk of PJP.

Comparison between closed suction drainage and nondrainage in total knee arthroplasty: a meta-analysis.

From individual randomized studies, it is not clear whether a closed suction drainage should be used after total knee arthroplasty. Our meta-analysis compares the clinical outcomes of closed suction drainage with nondrainage after total knee arthroplasty in randomized controlled trials reported between January 1966 and May 2010. Fifteen eligible trials involving 1361 knee incisions (686 knees with closed suction drainage and 675 knees without drainage) satisfied the inclusion criteria for our meta-analysis. The result of the meta-analysis indicates that closed suction drainage reduces the incidence of soft tissue ecchymosis and requirement for dressing reinforcement, but increases the rate of homologous blood transfusion. No significant difference between drainage and nondrainage was observed in the incidence of infection, deep venous thrombosis, or postoperative range of motion.

[Cartilage changes of femoral head osteonecrosis in stage II and III as detected by dGEMRIC].

OBJECTIVE: To detect the cartilage changes of hip joint with osteonecrosis of femoral head (ONFH) in stages II and III and provide evidence for understanding cartilage changes of femoral head of osteonecrosis before collapse. METHODS: The cartilage changes of ONFH were determined by delayed gadolinium enhanced magnetic resonance imaging of cartilage (dGEMRIC). According to ARCO classification of ONFH, the samples were divided into three groups: Group A, 11 hips, stageII; Group B, 13 hips, stage III; Group C, 10 hips, normal. All participates underwent the tests by dGEMRIC. And the data of T1Gd were collected and analyzed. RESULTS: The values of T1Gd were 420 ± 60 (Group A), 361 ± 54(Group B) and 538 ± 26 (Group C) respectively. There was a significant difference among three groups. The values of T1Gd in the ONFH patients were lower than their healthy counterparts. The values of TIGd of Group B was 14% lower than those of Group A. And the difference was significant statistically. CONCLUSION: Cartilage of the femoral head undergoes abnormal metabolic changes before collapse. There is a loss of GAG in the cartilage and it aggravates with the worsening of ONFH.

Robotic-assisted unicompartmental knee arthroplasty: a review.

PURPOSE: Presented here is an up-to-date review concerning robotic-assisted unicompartmental knee arthroplasty (rUKA), including its rationale, operative system, pros and cons. METHODS: We did a systematic research in electronic databases, including PubMed, Cochrane Library, Web of Science, and Embase up to March 30, 2020 to retrieve literature pertaining to rUKA. The search strategies "(robotic* AND knee arthroplasty OR knee replacement)" and "(knee arthroplasty OR knee replacement NOT total)" were used. Studies describing rUKA and clinical trials, dry bone or cadaveric researches regarding technologies, positioning, alignment, function, or survivorship of implants were included in this review. All retrieved studies were first browsed for eligibility on the basis of title and abstract, and the selected studies were further evaluated by reading full text for final inclusion. RESULTS: Robotic-assisted technology has been found to increase the accuracy of bone preparation and implant placement, reduce technical variability and outliers, and enhance reproduction of limb alignment. Additionally, early clinical outcomes were excellent, but mid-term follow-up showed no superiority in component survivorship. The potential drawbacks of the robotic-assisted technology include relatively-low time- and cost-effectiveness, development of some rUKA-related complications, and lack of support by high-quality literature. CONCLUSION: This review shows that rUKA can decrease the number of outliers concerning the optimal implant positioning and limb alignment. However, due to absence of extensive studies on clinical outcomes and long-term results, it remains unclear whether the improved component positioning translates to better clinical outcomes or long-term survivorship of the implant. Nevertheless, since an accurate implant position is presumably beneficial, robotic-assisted technology is worth recommendation in UKA.

Treatment of nontraumatic osteonecrosis of the femoral head using bone impaction grafting through a femoral neck window.

Nontraumatic osteonecrosis of the femoral head (non-ONFH) is a disorder that can lead to femoral head collapse and the need for total hip replacement. Various head-preserving procedures have been used for this disease to avert the need for total hip replacement. These include various vascularised and nonvascularised bone grafting procedures. We examined the effect of bone-grafting through a window at the femoral head-neck junction known as the "light bulb" approach for the treatment of osteonecrosis of the femoral head with a combination of demineralised bone matrix (DBM) and auto-iliac bone. The study included 110 patients (138 hips; 41 females, 69 males; mean age 32.36 years, range 17-54 years) with stage IIA-IIIA nontraumatic avascular necrosis of the femoral head according to the system of the ARCO (Association Research Circulation Osseous). The bone grafting procedure is called "light bulb" procedure in which the diseased bone was replaced by a bone graft substitute (combination of DBM and auto-iliac bone).The outcome was determined by the changes in the Harris hip score, by progression in radiographic stages, and by the need for hip replacement. The mean follow-up was 25.37 months (range 7-42 months). All data were processed by a statistics analysis including Cox risk model analysis and Kaplan-Meier survival analysis. Pre- and postoperative evaluations showed that the mean Harris hip score increased from 62 to 79. Clinically, 94 of 138 hips (68%) were successful at the latest follow-up, and radiological improvement was noted in 100% of patients in stage IIA, 76.67% of patients in stage IIB and 50.96% of patients in stage IIC and IIIA cases. Excellent and good results according to the Harris score were obtained in 100% of cases in stage IIA, 93.33% in stage IIB and 59.62% in stages IIIA and IIC stage, with a survivorship of 85% in stages IIA and IIB and 60% in stage IIIA and IIC cases. Cox risk model analysis showed that the clinical success rate correlated with both pre-operation stage and the necrotic area of the femoral head. The complications included ectopic ossification, lateral femoral cutaneous nerve lesion and joint infection. This procedure may be effective at avoiding or forestalling the need for total hip replacement in young patients with early to intermediate stages of osteonecrosis of the femoral head. Therefore, it may be the treatment of choice particularly in nontraumatic osteonecrosis of the femoral head of pre-collapse stage with small and middle area (<30%, or the depth of collapse <2 mm).

Treatment of nontraumatic osteonecrosis of the femoral head with the implantation of core decompression and concentrated autologous bone marrow containing mononuclear cells.

BACKGROUND: Since self-limited repair ability of the necrotic lesion may be a cause for failure of the technique, the possibility has been raised that bone marrow mononuclear cells (BMMCs) containing BMSCs implanted into a necrotic lesion of the femoral head with core decompression (CD) may be of benefit in the treatment of this condition. For this reason, we studied the implantation of the concentrated autologous bone marrow containing mononuclear cells in necrotic lesion of the femoral head to determine the effect of the method. METHODS: The study included 45 patients (59 hips, 9 females, 36 males; mean age 37.5 years, range 16-56 years) with stages I-IIIA nontraumatic avascular necrosis of the femoral head according to the system of the Association Research Circulation Osseous. Concentrated bone marrow (30-50 ml) containing mononuclear cells has been gained from autologous bone marrow (100-180 ml) obtained from the iliac crest of patient with the cell processor system. Concentrated bone marrow was injected through a CD channel into the femoral head. The outcome was determined by the changes in the Harris hip score, by progression in radiographic stages, and by the need for hip replacement. The mean follow-up was 27.6 months (range 12-40 months). RESULTS: Pre- and post-operative evaluations showed that the mean Harris hip score increased from 71 to 83. Clinically, the overall success is 79.7%, and hip replacement was done in 7 of the 59 hips (11.9%). Radiologically, 14 of the 59 hips exhibited femoral head collapse or narrowing of the coxofemoral joint space, and the overall failure rate is 23.7%. The number of BMMCs increased from 12.2 +/- 3.2 x 10(6)/ml to 35.2 +/- 12 x 10(6)/ml between pre-concentration and post-concentration. CONCLUSION: The concentrated autologous bone marrow containing mononuclear cells implantation relieves hip pain, prevents the progression of osteonecrosis. Therefore, it may be the treatment of choice particularly in stages I-II nontraumatic osteonecrosis of the femoral head.

Osteonecrosis in patients after severe acute respiratory syndrome (SARS): possible role of anticardiolipin antibodies.

OBJECTIVES: This study examined the anticardiolipin antibodies in post-SARS (severe acute respiratory syndrome) osteonecrosis patients to investigate the etiology of post-SARS osteonecrosis, and to eventually provide valuable information for the early diagnosis of nontraumatic osteonecrosis and for the susceptible population screening. METHODS: This study recruited 62 post-SARS osteonecrosis patients and 52 age- and gender-matched healthy controls. Fasting blood samples were collected from all the subjects through cubital veins. Immunoglobulins A, G and M (IgA, G and M) types of anticardiolipin antibodies were examined by enzyme-linked immunosorbent assay. The routine examinations of prothrombin time, thrombin time, prothrombin activity, and international normalized ratio were also performed. RESULTS: There were 21 of 62 post-SARS osteonecrosis patients (33.9%) who showed at least one type of anticardiolipin antibodies. The titers of specific IgA, IgG, and IgM were 11.33 +/- 11.209 APL, 5.127 +/- 5.927 GPL, and 17.821 +/- 10.606 MPL, respectively. There were only 4 of 52 subjects in the control group (7.7%) who showed positive anticardiolipin antibody with titers of IgA at 10.702 +/- 3.126 APL, IgG at 5.184 +/- 4.780 GPL, and IgM at 14.684 +/- 5.516 MPL. There were significant differences between the 2 groups confirmed by t-Test and chi(2) test (P < 0.05), while no significant differences were observed in prothrombin time, thrombin time, prothrombin activity, and international normalized ratio results between the 2 groups. CONCLUSIONS: The incidences of anticardiolipin antibodies were increased in the post-SARS osteonecrosis patients and anticardiolipin antibodies may play a role in the pathogenesis of post-SARS osteonecrosis.

[Comparison of short-median term outcome between total knee arthroplasty and unicondylar arthroplasty in patients with osteoarthritis affected with medial compartment mainly of the knee].

OBJECTIVE: To explore the short and mid-term outcome and surgical technique of minimally invasive unicondylar knee arthroplasty (UKA) for osteoarthritis affected with medial compartment predominantly of the knee. METHODS: From January 2003 to April 2009, all operations were performed by a senior surgeon. All patients followed the following criteria: (1) More than 50 years old and symptoms concentrated on the medial side of knee; (2) Osteoarthritis characterized mainly by medial compartment on X-rays and staged I-III by Ahlback staging system. There was no symptom of patellofemoral joint. Varus deformity was less than 15 degrees and flexuous deformity less than 10 degrees; (3) Knee joint was stable with intact main ligaments. METHODS: Forty-eight patients (48 knees) with osteoarthritis of the knee undergone UKA by minimally invasive surgery. The patients included 9 males and 39 females with an age range of 52 - 71 years old and a body mass index of 21.1 - 32.7. And 52 matched patients included 9 males and 39 females aged from 53 to 76 years old and with a body mass index of 21 - 32.4 undergone TKA. The pain and range of motion (ROM) of knees were evaluated by HSS score system before and after UKA and TKA. RESULTS: All patients were followed up for an average of 52.4 months (range: 12 - 82). In UKA group, all patients received pain relief and there was no continuous anterior knee pain. The range of motion of knee reached a median of 126 degrees and obtained a postoperative HSS score of 96 versus a preoperative score of 62. The rate of excellent and good outcome approached 97%. The results were similar in TKA group. However, in UKA group, the patients had a lesser blood loss, a faster recovery and a lower cost than those in TKA group. CONCLUSION: The short and mid-term outcome of UKA for osteoarthritis of knee affected with medial compartment is satisfactory. UKA is minimally invasive and has a faster recovery. Mild asymptomatic degeneration of patellofemoral joint and over-weight (BMI < 32) do not affect the short and mid-term outcome.

Role of Junction-Mediating and Regulatory Protein in the Pathogenesis of Glucocorticoid-Induced Endothelial Cell Lesions.

OBJECTIVE: Nontraumatic osteonecrosis of the femoral head (ONFH) is one of the most common diseases in orthopaedics. The damage to vascular endothelial (VE) cells caused by glucocorticoids (GC) has been reported as a possible mechanism of pathogenesis for ONFH. Junction-mediating and regulatory protein (JMY), originally identified as a p53 coactivator, plays prominent roles in the DNA damage response and in cell motility. This study aimed to discover the role of JMY in the pathogenesis of GC-induced endothelial cell lesions. METHODS: High-throughput RNA sequencing was performed to identify the differentially expressed genes between GC-treated human umbilical vein endothelial cells (HUVEC) and control cells. JMY knockdown and overexpressing HUVEC lines were treated with GC. Cell proliferation was examined with a survival cell count assay (Cell Counting Kit-8, CCK-8); cell apoptosis was measured by flow cytometry; a scarification assay was used to detect the capability of cell migration; a Transwell chamber assay was done to detect the cell motility . Differential expression of cell protein was detected by western blot. RESULTS: A total of 1561 differential genes were obtained through transcription sequencing, of which 789 mRNA were upregulated and 772 mRNA were downregulated in the GC-treated HUVEC compared with the control cells. CCK-8 assay results showed that: without GC treatment, overexpression or knockdown of JMY did not affect the proliferation activity of HUVEC. In the presence of GC treatment, the proliferation activity of HUVEC in the JMY knockdown group was significantly higher than that in the control group (P < 0.01). The proliferation activity of HUVEC in the overexpression JMY group was significantly lower than that in the control group (P < 0.01). The results of flow cytometry showed that without GC treatment, overexpression or knockdown of JMY did not affect the apoptosis proportion of HUVEC. With GC treatment, the apoptosis proportion of HUVEC in the JMY knockdown group was significantly lower than that in the control group (P < 0.01), and the apoptosis proportion of HUVEC in the overexpression JMY group was significantly higher than that in the control group (P < 0.01). Western blot results showed that with GC treatment, the JMY expression level of HUVEC increased with the reaction time. Moreover, the distribution of JMY was mainly concentrated in the nucleus. The expression level of Bax also increased with the reaction time. With GC treatment, overexpression of JMY could significantly increase the expression of Bax in HUVEC. JMY knockdown could reduce the expression of Bax in HUVEC. In the absence of GC treatment, HUVEC overexpression or knockdown of JMY did not affect the expression of Bax. The results of scarification and Transwell chamber assays showed that: without GC treatment, JMY knockdown could significantly decrease the cell motility and increase the expression level of VE-cadherin in HUVEC; with GC treatment, JMY knockdown in HUVEC had lower cell motility compared with the control group (P < 0.01). CONCLUSION: Glucocorticoids can induce the HUVEC apoptosis, and reduce its proliferation, cell motility. Our results mainly confirmed the role of JMY in the pathogenesis of GC-inducing lesions in HUVEC. GC act on HUVEC, inducing cell damage. Following the event of cell damage, JMY levels upregulate in the nucleus to induce transcription of Bax, triggering apoptosis. JMY can also regulate HUVEC motility via its regulation of VE-cadherin levels.

Comparison of Total Hip Arthroplasty after Two Types of Failed Hip Preserving Procedures with Primary Total Hip Arthroplasty.

OBJECTIVE: Porous tantalum implantation (PTI) and bone impaction grafting (BIG) through a window at the femoral head neck junction are known as two types of joint-preserving procedures. They provide an alternative option in the treatment of osteonecrosis of the femoral head by providing strong structural support to the subchondral plate. However, when earlier joint-preserving treatments fail, conversion to a total hip arthroplasty seems to be the final treatment of choice. This emphasizes the importance of joint-preserving procedures that do not hinder the clinical results of a subsequent total hip arthroplasty. The results of conversion total hip arthroplasty after failed PTI and BIG are still controversial. The purpose of this study was to compare the clinical and radiological outcomes of total hip arthroplasty after failed PTI or BIG surgery with primary total hip arthroplasty. METHODS: Patients at our institution between 2010 and 2014 who underwent total hip arthroplasty after failed PTI or BIG surgery compared to primary total hip arthroplasty were retrospectively reviewed. A total of 27 patients (30 hips) who underwent total hip arthroplasty after failed PTI surgery (group I) were matched according to age, gender and BMI index with 28 patients (30 hips) who underwent total hip arthroplasty after failed BIG surgery (group II) and 30 patients (30 hips) who underwent primary total hip arthroplasty (group III). The clinical results included preoperative and postoperative Harris Hip score, surgery duration, blood loss volume and clinical complications. Radiological follow-up results included abduction angle and anteversion angle of the acetabular cup, periprosthetic osteolysis, and prosthesis subsidence. RESULTS: There was no significant difference in the preoperative and postoperative Harris Hip score among the three groups at the latest follow-up (P = 0.247). The surgery duration was longer and intra-operative blood loss volume was higher in group I than in group II and group III (P < 0.05, respectively). There was no difference in surgery duration and blood loss volume between group II and group III (P > 0.05). There was no significant difference in radiological follow-up results among the three groups (P > 0.05). Varying degrees of residual tantalum debris were seen on postoperative radiographs of all group I patients. There was no difference in the incidence of complications among the three groups (P > 0.05). CONCLUSIONS: PTI group had higher blood loss volume and surgery duration than BIG group and primary total hip arthroplasty group. BIG group had no significant differences with primary total hip arthroplasty group in clinical and radiological follow-up results. There were no significant differences between the three groups in the Harris Hip score and radiological follow-up results.

Does new instrument for Oxford unicompartmental knee arthroplasty improve short-term clinical outcome and component alignment? A meta-analysis.

BACKGROUND: The Microplasty (MP) instrumentation designed for the Phase III Oxford mobile-bearing unicompartmental knee arthroplasty (UKA) system is considered a better option to achieve more accurate component positioning and alignment. In the present study, we focused on short-term clinical and radiological outcomes to determine whether the MP instrumentation can reduce the short-term revision rate and occurrence of outliers of metallic components. METHODS: The literature in PubMed, Embase, the Cochrane Library, and Web of Science was searched up to May 2020. Studies were scrutinized by two independent authors, and the revision rate, complication spectrum, and radiological assessment with outlier rates were specifically analyzed. RevMan 5.3 was used for the statistical analysis. RESULTS: Seven studies were included in the meta-analysis. Four studies reported both clinical and radiological outcomes, two reported only radiological outcomes, and one reported only clinical outcomes. The pooled analysis showed that the revision rate in the MP instrumentation group was 0.866 per 100 component years, while that in the control group was 1.124 (odds ratio, 0.77; p < 0.05). The subgroup analysis of the bearing dislocation rate showed a significantly greater reduction in the Korean population than in the populations of other countries (p < 0.05). The radiological assessment showed that the alignment of the femoral component was significantly improved (p < 0.05), while that of the tibial component was not (p > 0.05). CONCLUSION: The newly developed MP instrumentation for Oxford UKA significantly reduced the revision rate of this treatment. The positioning of the femoral component was also proven to be better by radiological assessments.

[Meta-analysis of unicompartmental knee arthroplasty versus high tibial osteotomy in the treatment of unicompartmental knee osteoarthritis].

OBJECTIVE: To assess the efficacy of UKA versus HTO in the treatment of unicompartmental knee osteoarthritis. METHODS: Comparative studies of UKA and HTO were retrieved from the domestic and foreign literatures and included for a meta-analysis. RESULTS: Seven eligible randomized controlled trials included 196 UKAs and 219 HTOs. The result of Meta-analysis indicated that the ratio for an excellent outcome was higher in UKA than HTO. The combined OR was 2.43, 95%CI (1.46, 4.05) (P = 0.0006). The risks of revision and complications were lower in UKA than HTO. The combined OR was 0.47 and 0.24 and 95%CI (0.23, 0.97), (0.10, 0.56). CONCLUSION: UKA reduces the risk of postoperative revision and complications and provides excellent outcomes.

A modified technique for tibial bone sparing in unicompartmental knee arthroplasty.

BACKGROUND: Previously, the authors modified the surgical technique to preserve tibial bone mass for Oxford unicompartmental knee arthroplasty (UKA). The purpose of this study was to determine the clinical outcomes and values of this modified technique. METHODS: Clinical data of 34 consecutive patients who underwent the unilateral modified UKA technique (modified group, 34 knees) were retrospectively analyzed. To compare the outcome, a match-paired control group (conventional group, 34 knees) of an equal number of patients using the conventional technique system in the same period were selected and matched with respect to diagnosis, age, pre-operative range of motion (ROM), and radiological grade of knee arthrosis. Clinical outcomes including knee Hospital for Special Surgery (HSS) score, ROM, and complications were compared between the two groups. Post-operative radiographic assessments included hip-knee-ankle angle (HKA), joint line change, implant position, and alignment. RESULTS: The mean follow-up time was 38.2 ±â€Š6.3 months. There was no difference in baseline between the two groups. The amount of proximal tibial bone cut in the modified group was significantly less than that of the conventional group (4.7 ±â€Š1.1 mm vs. 6.7 ±â€Š1.3 mm, t = 6.45, P < 0.001). Joint line was elevated by 2.1 ±â€Š1.0 mm in the modified group compared with -0.5 ±â€Š1.7 mm in the conventional group (t = -7.46, P < 0.001). No significant differences were observed between the two groups after UKA with respect to HSS score, VAS score, ROM, and HKA. Additionally, the accuracy of the post-operative implant position and alignment was similar in both groups. As for implant size, the tibial implant size in the modified group was larger than that in the conventional group (χ = 4.95, P = 0.035). CONCLUSIONS: The modified technique for tibial bone sparing was comparable with the conventional technique in terms of clinical outcomes and radiographic assessments. It can preserve tibial bone mass and achieve a larger cement surface on the tibial side.

Rates of periprosthetic infection and surgical revision in Beijing (China) between 2014 and 2016: a retrospective multicenter cross-sectional study.

BACKGROUND: Periprosthetic joint infection (PJI) is a rare but devastating complication after total joint arthroplasty. There is a paucity of data on the incidence and prevalence of periprosthetic infection in mainland China. This study aimed to analyze the rates of surgical revision after arthroplasty due to PJI and the procedures followed in Beijing, China. METHODS: The study involved a retrospective multicenter cross-sectional survey of patients undergoing revisions for periprosthetic infection after hip/knee arthroplasty at nine hospitals in Beijing from 2014 to 2016. Age, gender, body mass index, primary diagnosis, comorbidity, primary surgery, treatment methods, and post-revision complications were analyzed. RESULTS: A total of 38,319 hip/knee arthroplasties and 366 (0.96%) revisions for PJI were identified. Of these, 161 (161/14,110; 1.14%) revisions involved hip arthroplasty, whereas 205 (205/24,209; 0.85%) revisions were due to knee arthroplasty. Procedures for revisions of infected hip included 7 (4.3%) cases of open debridement and prosthesis retention, 32 (19.9%) cases of one-stage exchange, 121 (75.2%) cases of two-stage exchange, and 1 (0.007%) case of hip dissection. As for the infected knee, the procedures included 45 (22.0%) cases of open debridement and prosthesis retention, 13 (6.3%) cases of one-stage exchange, 143 (69.8%) cases of two-stage exchange, and 4 (0.02%) cases of knee fusion. CONCLUSIONS: The study found the rates of revision due to PJI to be low. Nonetheless, the incidence of PJI in mainland China could be higher and calls for more elaborate studies in geographically and socioeconomically diverse health institutions.

Decreased proliferation of mesenchymal stem cells in corticosteroid-induced osteonecrosis of femoral head.

The ability of self-repair in patients with corticosteroid-induced osteonecrosis of the femoral head is limited, and it has been suggested the cause is likely relevant to the poor proliferation activity of mesenchymal stem cells in the femoral head region. This study measured the number and proliferation activity of human mesenchymal stem cells in patients both with and without corticosteroid-induced osteonecrosis of the femoral head. Bone marrow was collected from the proximal femur in patients with steroid-induced osteonecrosis of the femoral head (osteonecrosis group, n=18) and patients with new femoral neck fractures without osteonecrosis (control group, n=11). Mesenchymal stem cells were isolated by density gradient centrifugation, and then selected by the adhesive method. The MTT reduction assay method was used to evaluate the level of proliferation. Cells from osteonecrosis patients showed reduced proliferation ability compared with the control patients. The percentage of cells in the S+G2/M phase was decreased significantly (P<.01) in the osteonecrosis group. The decreased proliferation ability of mesenchymal stem cells may play a role in the low repair capacity of steroid-induced osteonecrosis of femoral head. The altered function of mesenchymal stem cells may be responsible for the pathogenesis and progression of osteonecrosis.

[The effect of subchondral bone defect in femoral head on structure and metabolism of article cartilage].

OBJECTIVE: To investigate the changes of structure and metabolism of the cartilage of femoral head overlying the bone defect in animal model and analyse the possible effect of the necrotic area of the femoral head on the cartilage overlying there. METHODS: 18 adult hybrid dogs was applied for bone defect model of femoral head. Of the femoral heads, the left was applied for bone defect model, the right for shame-operation. 5, 5, and 8 animals were sacrificed respectively 4, 12 and 24 weeks after operation and the femoral heads were received for examinations. The X-rays films were taken just before the animals were sacrificed. After the cartilage specimens were decalcified, dehydrated and embedded, sections 6, u thick were made. They were stained with hematoxylin-eosin, sirius-red and toilude blue. The biochemical assay were performed. RESULTS: 12 and 24 weeks after operation of bone defect, cartilage histology and biochemistry demonstrated the signs of articular cartilage pathological changes. The arrangement of chondrocytes were disorder. The number of chondrocytes decreased. The cartilage surface lost its smoothness, and these kinds of changes were more severe in the area next to the bone defect. Fibrosis and vasi formation were found. Tidemark had the changes of discontinuation and veil. Glycosaminoglycans decreased. CONCLUSION: The bone defect, whose damaged structure strength and decreased blood supply is similar, had effect on the structure and metabolism of the articular cartilage near the bone defect, and suggest osteonecrosis at the stage of pro-collapse may affect the cartilage overlying it.