A modified technique for tibial bone sparing in unicompartmental knee arthroplasty / 中华医学杂志(英文版)

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 ± 6.3 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 ± 1.1 mm vs. 6.7 ± 1.3 mm, t = 6.45, P < 0.001). Joint line was elevated by 2.1 ± 1.0 mm in the modified group compared with -0.5 ± 1.7 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.

A modified technique for tibial bone sparing in unicompartmental knee arthroplasty / 中华医学杂志(英文版)

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 ± 6.3 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 ± 1.1 mm vs. 6.7 ± 1.3 mm, t = 6.45, P < 0.001). Joint line was elevated by 2.1 ± 1.0 mm in the modified group compared with -0.5 ± 1.7 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 (χ2 = 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.

An innovative three-dimensional method for identifying a proper femoral intramedullary entry point in total knee arthroplasty / 中华医学杂志(英文版)

<p><b>Background:</b>Identification of the proper femoral intramedullary (IM) access point is an important determinant of final implant position in IM-guided total knee arthroplasty (TKA). The aim of this study was to identify the optimal entry point in Chinese participants using a new three-dimensional method.</p><p><b>Methods:</b>A series of computed tomography scans of 44 femurs in Chinese participants from October 2014 to October 2015 were imported into Mimics 17.0 software to identify the optimal entry point. The apex of the intercondylar notch (AIN) was used as the reference bony anatomical landmark to identify the proper entry point to insert the IM rod. The statistical significance was calculated on the basis of a 5% level (P < 0.05) using the Student's t-test.</p><p><b>Results:</b>For the males, the average ideal entry point was 1.49 mm medial and 13.39 mm anterior to the AIN. The values were 1.77 mm medial and 15.29 mm anterior to the AIN in females. A significant difference was present between males and females (13.39 ± 2.46 mm vs. 15.29 ± 3.44 mm, t = 2.124, P = 0.040). When using the recommended location as the entry point for the IM rod, the mean potential error differed significantly from the femoral trochlear groove (the potential error of IM in males in coronal plane: 0.93° ± 0.24° vs. 1.27° ± 0.32°, t = -4.166, P <0.001; the potential error of IM in males in sagittal plane: 1.40° ± 0.42° vs. 2.79° ± 0.70°, t = 7.155, P < 0.001; the potential error of IM in females in coronal plane: 0.73° ± 0.28° vs. 1.15° ± 0.35°, t = 3.940, P < 0.001; and the potential error of IM in females in sagittal plane: 1.48° ± 0.47° vs. 2.76° ± 0.83°, t =5.574, P < 0.001). A significant difference was present between the recommended point and the point 10 mm anterior to the origin of the posterior cruciate ligament (the potential error of IM in males in coronal plane: 0.93° ± 0.24° vs. 1.53° ± 0.43°, t = 5.948, P < 0.001; the potential error of IM in males in sagittal plane: 1.40° ± 0.42° vs. 2.15° ± 0.75°, t = 3.152, P = 0.003; the potential error of IM in females in coronal plane: 0.73° ± 0.28° vs. 1.28° ± 0.42°, t = -4.632, P < 0.001; and the potential error of IM in females in sagittal plane: 1.48° ± 0.47° vs. 2.40° ± 0.93°, t = 3.763, P = 0.001).</p><p><b>Conclusions</b>The technique described here is an innovative method for swift, easy, and accurate access to the medullary canal during TKA, and it can optimize the position and orientation of the prosthetic components in knee arthroplasty.</p>

Application of lower edge of teardrop on restoring anatomical hip center height in total hip arthroplasty / 中国组织工程研究

BACKGROUND: The position of acetabular prosthesis is very important in total hip arthroplasty; its ideal position is to restore its anatomical hip center of rotation. As the inferior edge of the teardrop is an important stable imaging marker, it is of great significance to evaluate the position of acetabular cup and guide the correct intraoperative placement of prosthesis. OBJECTIVE: To investigate the effect of the lower edge of the teardrop on restoring anatomical hip center height in total hip arthroplasty. METHODS: Medical records and anteroposterior images of 107 unilateral total hip arthroplasty with normal contralateral acetabulum and lower edge of cup at the same level as lower edge of the teardrop were reviewed. Center height and horizontal distance as well as cup inclination and anteversion were measured radiographically. The paired t test was used to compare data between left and right sides of hip center height. Scatterplots and Pearson's correlation coefficients were used to evaluate the association between the difference of the height of two hip centers, cup anteversion and inclination angle. RESULTS AND CONCLUSION: (1) The height of cup center was significantly higher than that of contralateral hip joint center (P < 0.001). Whereas 93.4% (100 cases) of absolute differences between them were in the range from 0 mm to 5 mm, only 6.6% (7 cases) were more than 5 mm. (2) However, when the lower edge of cup was 1.5-2.0 mm inferior to the lower edge of the teardrop, there was no statistical differences between them (P=0.345 and 0.331). (3) There was a weak correlation between the difference of the height of two hip centers with inclination and anteversion (r=0.376, 0.310, P < 0.001). (4) The position of cup with its inferior edge 1.5-2.0 mm below the inferior edge of the teardrop can exactly replicate the anatomic hip center.

Glycosaminoglycan Content of the Lateral Compartment Cartilage in Knees Conforming to the Indications for Oxford Medial Unicompartmental Knee Arthroplasty / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The quality of the lateral compartment cartilage is important to preoperative evaluation and prognostic prediction of unicompartmental knee arthroplasty (UKA). Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) enables noninvasive assessment of glycosaminoglycan (GAG) content in cartilage. This study aimed to determine the GAG content of the lateral compartment cartilage in knees scheduled to undergo Oxford medial UKA.</p><p><b>METHODS</b>From December 2016 to May 2017, twenty patients (20 osteoarthritic knees) conforming to the indications for Oxford medial UKA were included as the osteoarthritis (OA) group, and 20 healthy volunteers (20 knees) paired by sex, knee side, age (±3 years), and body mass index (BMI) (±3 kg/m2) were included as the control group. The GAG contents of the weight-bearing femoral cartilage (wbFC), the posterior non-weight-bearing femoral cartilage (pFC), the lateral femoral cartilage (FC), and tibial cartilage (TC) were detected using dGEMRIC. The dGEMRIC indices (T1Gd) were calculated in the middle three consecutive slices of the lateral compartment. Paired t-tests were used to compare the T1Gd in each region of interest between the OA group and control group.</p><p><b>RESULTS</b>The average age and BMI in the two groups were similar. In the OA group, T1Gd of FC and TC was 386.7 ± 50.7 ms and 429.6 ± 59.9 ms, respectively. In the control group, T1Gd of FC and TC was 397.5 ± 52.3 ms and 448.6 ± 62.5 ms, respectively. The respective T1Gd of wbFC and pFC was 380.0 ± 47.8 ms and 391.0 ± 66.3 ms in the OA group and 400.3 ± 51.5 ms and 393.6 ± 57.9 ms in the control group. Although the T1Gd of wbFC and TC tended to be lower in the OA group than the control group, there was no significant difference between groups in the T1Gd in any of the analyzed cartilage regions (P value of wbFC, pFC, FC, and TC was 0.236, 0.857, 0.465, and 0.324, respectively).</p><p><b>CONCLUSIONS</b>The GAG content of the lateral compartment cartilage in knees conforming to indications for Oxford medial UKA is similar with those of age- and BMI-matched participants without OA.</p>

Effects of Lower Limb Alignment and Tibial Component Inclination on the Biomechanics of Lateral Compartment in Unicompartmental Knee Arthroplasty / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Lateral compartmental osteoarthritis (LCOA), a major complication after medial mobile-bearing unicompartmental knee arthroplasty (UKA), is highly associated with the increased stress of the lateral compartment. This study aimed to analyze the effects on the stress and load distribution of the lateral compartment induced by lower limb alignment and coronal inclination of the tibial component in UKA through a finite element analysis.</p><p><b>METHODS</b>Eight three-dimensional models were constructed based on a validated model for analyzing the biomechanical effects of implantation parameters on the lateral compartment after medial Oxford UKA: postoperative lower limb alignment of 3° valgus, neutral and 3° varus, and the inclination of tibial components placed in 4°, 2° valgus, square, and 2° and 4° varus. The contact stress of femoral and tibial cartilage and load distribution were calculated for all models.</p><p><b>RESULTS</b>In the 3° valgus lower limb alignment model, the contact stress of femoral (3.38 MPa) and tibial (3.50 MPa) cartilage as well as load percentage (45.78%) was highest compared to any other model, and was increased by 36.75%, 47.70%, and 27.63%, respectively when compared to 3° varus. In the condition of a neutral position, the outcome was comparable for the different tibial tray inclination models. The inclination did not greatly affect the lateral compartmental stress and load distribution.</p><p><b>CONCLUSIONS</b>This study suggested that slightly varus (undercorrection) lower limb alignment might be a way to prevent LCOA in medial mobile-bearing UKA. However, the inclination (4° varus to 4° valgus) of the tibial component in the coronal plane would not be a risk factor for LCOA in neutral position.</p>

Significance of Lateral Pillar in Osteonecrosis of Femoral Head: A Finite Element Analysis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The lateral pillar of the femoral head is an important site for disease development such as osteonecrosis of the femoral head. The femoral head consists of medial, central, and lateral pillars. This study aimed to determine the biomechanical effects of early osteonecrosis in pillars of the femoral head via a finite element (FE) analysis.</p><p><b>METHODS</b>A three-dimensional FE model of the intact hip joint was constructed from the image data of a healthy control. Further, a set of six early osteonecrosis models was developed based on the three-pillar classification. The von Mises stress and surface displacements were calculated for all models.</p><p><b>RESULTS</b>The peak values of von Mises stress in the cortical and cancellous bones of normal model were 6.41 MPa and 0.49 MPa, respectively. In models with necrotic lesions in the cortical and cancellous bones, the von Mises stress and displacement of lateral pillar showed significant variability: the stress of cortical bone decreased from 6.41 MPa to 1.51 MPa (76.0% reduction), while cancellous bone showed an increase from 0.49 MPa to 1.28 MPa (159.0% increase); surface displacements of cortical and cancellous bones increased from 52.4 μm and 52.1 μm to 67.9 μm (29.5%) and 61.9 μm (18.8%), respectively. In addition, osteonecrosis affected not only pillars but also adjacent structures in terms of the von Mises stress and surface displacement levels.</p><p><b>CONCLUSIONS</b>This study suggested that the early-stage necrosis in the femoral head could increase the risk of collapse, especially in lateral pillar. On the other hand, the cortical part of lateral pillar was found to be the main biomechanical support of femoral head.</p>

Local Administration of Bisphosphonate-soaked Hydroxyapatite for the Treatment of Osteonecrosis of the Femoral Head in Rabbit / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Systemic administration of bisphosphonates has shown promising results in the treatment of osteonecrosis of the femoral head (ONFH). However, few studies have evaluated the efficacy of local zoledronate (ZOL) administration in the treatment of ONFH. The purpose of this study was to investigate whether local administration of bisphosphonate-soaked hydroxyapatite (HA) could improve bone healing in an experimental rabbit model of ONFH.</p><p><b>METHODS</b>This experimental study was conducted between October 2014 and June 2015. Forty-five rabbits underwent simulated ONFH surgery. Immediately following surgery, they were divided into three groups: model (untreated, n = 15), HA (treated with HA alone, n = 15), and HA + ZOL (treated with HA soaked in a low-dose ZOL solution, n = 15). Histological, immunohistochemical, and quantitative analyses were performed to evaluate bone formation and resorption 2, 4, and 8 weeks after surgery.</p><p><b>RESULTS</b>Gross bone matrix and hematopoietic tissue formation were observed in the HA + ZOL group 4 weeks after surgery. The immunohistochemical staining intensities for 5-bromodeoxyuridine, runt-related transcription factor 2, osteocalcin, osteopontin, and osteoprotegerin were significantly higher in the HA + ZOL group than that in the model (P < 0.001, P< 0.001, P< 0.001, P< 0.001, and P = 0.018, respectively) and HA groups (P = 0.003, P = 0.049, P< 0.001, P = 0.020, and P = 0.019, respectively), whereas receptor activator of the nuclear factor-κB ligand staining intensity was significantly lower in the HA + ZOL group than that in the model and HA groups (P = 0.029 and P = 0.015, respectively) 4 weeks after surgery. No significant differences in bone formation or bone resorption marker expression were found between the three groups 2 or 8 weeks after surgery (P > 0.05).</p><p><b>CONCLUSIONS</b>Local administration of HA soaked in a low-dose ZOL solution increased new bone formation while inhibiting bone resorption in an animal model of ONFH, which might provide new evidence for joint-preserving surgery in the treatment of ONFH.</p>

Glucocorticoids Significantly Influence the Transcriptome of Bone Microvascular Endothelial Cells of Human Femoral Head / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Appropriate expression and regulation of the transcriptome, which mainly comprise of mRNAs and lncRNAs, are important for all biological and cellular processes including the physiological activities of bone microvascular endothelial cells (BMECs). Through an intricate intracellular signaling systems, the transcriptome regulates the pharmacological response of the cells. Although studies have elucidated the impact of glucocorticoids (GCs) cell-specific gene expression signatures, it remains necessary to comprehensively characterize the impact of lncRNAs to transcriptional changes.</p><p><b>METHODS</b>BMECs were divided into two groups. One was treated with GCs and the other left untreated as a paired control. Differential expression was analyzed with GeneSpring software V12.0 (Agilent, Santa Clara, CA, USA) and hierarchical clustering was conducted using Cluster 3.0 software. The Gene Ontology (GO) analysis was performed with Molecular Annotation System provided by CapitalBio Corporation.</p><p><b>RESULTS</b>Our results highlight the involvement of genes implicated in development, differentiation and apoptosis following GC stimulation. Elucidation of differential gene expression emphasizes the importance of regulatory gene networks induced by GCs. We identified 73 up-regulated and 166 down-regulated long noncoding RNAs, the expression of 107 of which significantly correlated with 172 mRNAs induced by hydrocortisone.</p><p><b>CONCLUSIONS</b>Transcriptome analysis of BMECs from human samples was performed to identify specific gene networks induced by GCs. Our results identified complex RNA crosstalk underlying the pathogenesis of steroid-induced necrosis of femoral head.</p>

Finite Element Analysis of Mobile-bearing Unicompartmental Knee Arthroplasty: The Influence of Tibial Component Coronal Alignment / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Controversies about the rational positioning of the tibial component in unicompartmental knee arthroplasty (UKA) still exist. Previous finite element (FE) studies were rare, and the results varied. This FE study aimed to analyze the influence of the tibial component coronal alignment on knee biomechanics in mobile-bearing UKA and find a ration range of inclination angles.</p><p><b>METHODS</b>A three-dimensional FE model of the intact knee was constructed from image data of one normal subject. A 1000 N compressive load was applied to the intact knee model for validating. Then a set of eleven UKA FE models was developed with the coronal inclination angles of the tibial tray ranging from 10° valgus to 10° varus. Tibial bone stresses and strains, contact pressures and load distribution in all UKA models were calculated and analyzed under the unified loading and boundary conditions.</p><p><b>RESULTS</b>Load distribution, contact pressures, and contact areas in intact knee model were validated. In UKA models, von Mises stress and compressive strain at proximal medial cortical bone increased significantly as the tibial tray was in valgus inclination >4°, which may increase the risk of residual pain. Compressive strains at tibial keel slot were above the high threshold with varus inclination >4°, which may result in greater risk of component migration. Tibial bone resection corner acted as a strain-raiser regardless of the inclination angles. Compressive strains at the resected surface slightly changed with the varying inclinations and were not supposed to induce bone resorption and component loosening. Contact pressures and load percentage in lateral compartment increased with the more varus inclination, which may lead to osteoarthritis progression.</p><p><b>CONCLUSIONS</b>Static knee biomechanics after UKA can be greatly affected by tibial component coronal alignment. A range from 4° valgus to 4° varus inclination of tibial component can be recommended in mobile-bearing UKA.</p>

A method for isolated culture of bone microvascular endothelial cells of human femoral head / 中国骨伤

<p><b>OBJCETIVE</b>To investigate the method of separation of culture of bone microvascular endothelial cells (BMECs) of human femoral head in vitro.</p><p><b>METHODS</b>From October 2013 to January 2014,15 femoral heads without pathologic change from patients resected during hip replacement were selected involving 2 males and 13 females with a mean age of 71.2 years old ranging from 38 to 92. Cancellous bone in femoral head was bited into broken bone grain and transfered into medium in aseptic contidion. Cells were isolated by the methods of enzymic digestion and density gradient centrifugation,purified by differiential attachment. The characteristics of cells was observed by inverted microscope. vWF and CD31 immunofluorescence analysis was applied for identification of cells.</p><p><b>RESULTS</b>The number of cells was positively correlated with patients' age after 24 hours in primary culture. The older patients had the less cells numbered. After 4 to 5 days' culture, primary cells appeared short spindle,polygon shaped and cobblestone-like morphology. After 7 to 10 days' culture, primary cells proliferated densely, became fusion, arranged in swirl, and contact inhibition appeared significantly. Immunofluorescence staining revealed the cells were 100% positive for vWF and CD31, and it showed that the cultured cells were BMECs.</p><p><b>CONCLUSION</b>It was a simple, steady, effective method with good reproducibility, by which highly purified human BMECs can be obtained.</p>

Efficacy of multimodal cocktail periarticular injection with or without steroid in total knee arthroplasty / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Multimodal cocktail periarticular injection (MCPI) with a large volume of low concentration local anesthetics, adrenaline, and anti-inflammatory agents such as non-steroidal anti-inflammatory drug or steroids have shown good pain control and improvement in range of motion after surgery. This study compares the efficacy of pain control after total knee arthroplasty, using multimodal cocktail periarticular injection with steroid or without steroid.</p><p><b>METHODS</b>This is a prospective, double-blinded, randomized and control study. Seventy-two patients with osteoarthritis that met clinical criteria for total knee arthroplasty were recruited into the study, and were randomized to receive either multimodal cocktail periarticular injection with steroid or without steroid. Pain was assessed by visual analogue scale (VAS) at preoperative and postoperative at rest, and during activity. The range of motion was recorded preoperatively and postoperatively. The amount of daily and cumulative morphine consumption were measured by patient-controlled analgesia in the first 72 hours postoperatively. The duration of celecoxib usage was also recorded at the last follow-up.</p><p><b>RESULTS</b>There were no differences between the non-steroid and steroid groups with regard to VAS at rest and during activity, or range of motion, at any postoperative observation time. The postoperative Knee Society Knee Score in the steroid group improved significantly as compared with that in non-steroid group at the one-month (84.1±13.1 and 65.9±12.1; P < 0.0045), three-month follow-up (90.2±16.3 and 72.5±16.6; P < 0.0027), but after postoperative six-month the Knee Society Knee Score showed no significant difference between the groups. There was no significant difference in consumption of the morphine about daily or total consumption within 72 hours between the two groups. The duration of celecoxib usage in patients in the steroid group was significantly shorter than that in the non-steroid group ((7.2±0.7) compared with (10.5±1.9) weeks; P = 0.012).</p><p><b>CONCLUSION</b>The patients who received the steroid injection had faster rehabilitation and less non-steroidal antiinflammatory drugs consumption.</p>

Effect of continuous femoral nerve block in analgesia and the early rehabilitation after total knee replacement / 中国骨伤

<p><b>OBJECTIVE</b>To evaluate the benefit and safety of continuous femoral nerve block in patients undergoing total knee arthroplasty.</p><p><b>METHODS</b>From December 2008 to August 2009, 80 patients with total knee arthroplasty were randomly divided into two groups, 40 patients in each group. In group A the pain-control was dominanted by continuous femoral nerve block, there were 5 males adn 35 females with an average age of (65.0 +/- 4.2) years old; In group B the pump of vein odynolysis was used, there were 5 males and 35 females with an average age of (64.7 +/- 8.5) years old. The treatment of relieve pain continued for 3 days. The pain of visual analog scale (VAS), sleep condition, early-stage rehabilitation and adverse effects were recorded.</p><p><b>RESULTS</b>The VAS scores of group A was lower than that of group B at 2, 6, 24, 36, 48, 56, 72 h after operation (P < 0.05 or P < 0.01); The sleep condition and early-stage rehabilitation of group A were better than that of group B. The complications of group B occurrenced more than group A; The analgetica of group B were used more than that of group A.</p><p><b>CONCLUSION</b>The continuous femoral nerve block is an effective pain relieve method and is benefical to rehabilitation from total knee arthroplasty early.</p>

Intervention of Poloxamer 188 to chondrocyte damaged by blunt mechanical trauma in vitro / 中华外科杂志

<p><b>OBJECTIVE</b>To explore Poloxamer 188, a non-ionic surfactant as a potential tool for early intervention into the chondrocyte damaged by blunt mechanical trauma in vitro.</p><p><b>METHODS</b>Three groups were control group (n = 6), no treatment group (n = 12) and Poloxamer 188 treatment group (n = 12). Two groups are then loaded to 20 MPa in unconfined compression. At 1 and 24 h the percentages of live and dead cells of superficial zone in compressed and control groups were determined with a cell viability stain.</p><p><b>RESULTS</b>At 1 h post-trauma, specimens of Poloxamer 188 treatment group (76%) had a significantly increased percentage of live cells in the superficial zone versus the no treatment group (55%). In 24 h the percentages of live cells in the superficial zone of the Poloxamer 188 treatment group (57%) were significantly greater than in the no treatment group (38%).</p><p><b>CONCLUSIONS</b>Poloxamer 188 surfactant could help restore the integrity of cell membranes in cartilage damaged by blunt mechanical trauma. Models of mechanical cartilage injury in vitro may explain aspect of the interactions between mechanical forces and degradative pathways which lead to osteoarthritis progression.</p>

Clinical research of correlation between osteonecrosis and steroid / 中华外科杂志

<p><b>OBJECTIVE</b>To explore the correlation between the dosage of corticosteroid, time of onset and incidence of osteonecrosis (ON) in patients with SARS.</p><p><b>METHODS</b>From July 2003 to January 2004, general survey carried out for ON in 551 patients with SARS. Five hundred and fifty-one patients except 12 were administrated by corticosteroid from 80 mg to 30 000 mg. The age of patients was (33 +/- 9) years old ranging from 19 to 59 years old. One hundred and thirty-one were male, and four hundred and twenty were female. MRI and X-ray film were taken in all patients including both hips, knees, shoulders, ankles and wrists. CT scan was taken in partial patients. Common classification system were used for staging of hip (ARCO), knee (Lotka) and shoulder (Cruess). Independent test, rank-sum test and multiple factor logistic regression analysis were used for statistical analysis.</p><p><b>RESULTS</b>No osteonecrosis was detected in 12 patients without corticosteroid. Osteonecrosis was detected in 176 patients (32.7 percent) among 539 patients. There were ON of femoral head in 130 cases (210 hips), ON of knee in 98 cases (130 knees), ON of humeral head in 21 cases (36 shoulders), ON of talus and calcaneus in 16 cases (26 ankles), ON of scaphoid and lunate in 11 cases (17 wrists), ON of patella in 3 cases (4 patella), ON of ilium in 1 case and bone infarction (femur, tibia) in 18 cases. One hundred and nineteen cases (195 hips) with ONFH were in stage I (IA 45 hips, IB 77 hips, IC 73 hips). Eleven cases (15 hips) were in stage II. All osteonecrosis of the knee and humoral head was stage I. Thirty-four patients with ON had one joint affected, 45 patients had 2 joints, 93 patients had more than 3 joints. The dosage of corticosteroid was (5842 +/- 4988) mg in ON group and (2719 +/- 2571) mg in non-ON group (P < 0.0001). The duration of steroid was (38 +/- 17) d in ON group and (27 +/- 15) d in non-ON group (P < 0.01). The dosage of pulse treatment was (340 +/- 207) mg/d in ON group and (211 +/- 160) mg/d in non-ON group (P < 0.01). The duration of pulse treatment was (28 +/- 13) d in ON group and (18 +/- 11) d in non-ON group (P < 0.01). All patients with ON were detected within 6 months from administration.</p><p><b>CONCLUSION</b>About one-third patients with SARS who were treated with a high dose of corticosteroid occurred osteonecrosis. ON is frequently multiple focuses. The actual time of onset of ON is early of steroid used. MRI is golden standard for early diagnosis of ON. The patients who were treated with a high dose of corticosteroid should be inspected initially by MRI.</p>