Crosslinking chitosan with glucose via the modified Maillard reaction promotes the osteoinduction of mouse MC3T3-E1 pre-osteoblasts

Bone defects are a common clinical issue, but therapeutic efficiency can be challenging in cases of more considerable traumas or elderly patients with degenerated physiological metabolism. To address this issue, a more suitable cell-biomaterial construct promoting bone regeneration has been extensively investigated, with the chitosan scaffold being considered a potential candidate. In this study, chitosan was crosslinked with different doses of glucose (CTS-10~50%Glc) using a modified Maillard reaction condition to develop a more appropriate cell-biomaterial construct. Mouse MC3T3-E1 pre-osteoblasts were seeded onto the scaffolds to examine their osteoinductive capability. The results showed that CTS-Glc scaffolds with higher glucose contents effectively improved the adhesion and survival of mouse MC3T3-E1 pre-osteoblasts and promoted their differentiation and mineralization. It was further demonstrated that the membrane integrin α5 subunit of pre-osteoblasts is the primary adhesion molecule that communicates with CTS-Glc scaffolds. After that, Akt signaling was activated, and then bone morphogenetic protein 4 was secreted to initiate the osteoinduction of pre-osteoblasts. The prepared CTS-Glc scaffold, with enhanced osteoinduction capability and detailed mechanism elucidations, offers a promising candidate material for advancing bone tissue engineering and clinical regenerative medicine. As a result, this study presents a potential tool for future clinical treatment of bone defects.

The role of postoperative piriformis fossa and greater trochanter tubercle distance to predict cutout failure after cephalomedullary nail fixation

BACKGROUND

This study investigated the association between postoperative piriformis fossa and greater trochanter tubercle distance (distance from the deepest point of piriformis fossa to the most lateral greater trochanter tubercle [PG]) and cutout failure after cephalomedullary nail (CMN) osteosynthesis for intertrochanter fracture (ITF). A rotating femur model was designed to analyze PG variation during femur rotation.

METHODS

From 2005 to 2010, 311 patients diagnosed of ITF (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association [AO/OTA] 31-A2 and A3) underwent CMN fixation at our institute were reviewed. Of these, 281 (90.3%) patients achieved union without complication, 21 (6.8%) had cutout failure, six (1.9%) had femoral head osteonecrosis, and three (1%) had nonunion during postoperative 2-year follow-up. The side difference of postoperative PG compared to contralateral uninjured hip (dPG) was analyzed between patients who had cutout failure and those who did not. In the rotating femur model, the PG was measured for every 2.5° increments of internal and external rotation from 0° to 50°.

RESULTS

The dPG was significantly higher in the failure group (10.2 ± 4.2 vs 6.6 ± 3.5 mm, p <0.001). The odds ratio for lag screw cutout was 6.35 (95% CI, 1.10-11.6, p =0.003) for every 1 mm dPG increment. dPG exhibited high diagnostic performance in predicting cutout failure according to receiver operating characteristic curve analysis. The area under the curve was 0.774 (95% CI, 0.711-0.837). dPG yielded the greatest sensitivity (78.4%) and specificity (78.4%) to predict lag screw cutout when cutoff value being 8.65 mm. In rotating femur model, PG change from baseline demonstrated significant ( p <0.001) positive and negative correlation with increased external and internal rotation, respectively.

CONCLUSION

Increased dPG is a risk factor of cutout failure for ITF osteosynthesis with CMN. In conjunction with tip-apex distance, fracture displacement, and reduction quality; dPG can help surgeons interpret postoperative radiograph and predict failure. However, it should be noticed that a proper and standard patient positioning is critical for accurate dPG measurement.

Natural progression of the pubofemoral distance with age and its correlation with future acetabular index

OBJECTIVES

This study investigated the progression of pubofemoral distance (PFD) with age and assessed the correlation between PFD and late acetabular index (AI) measurements.

METHODS

This prospective observational study was conducted between January 2017 and December 2021. We enrolled 223 newborns who underwent the first, second, and third hip ultrasounds, and pelvis radiograph at a mean age of 18.6 days, 3.1 months, 5.2 months, and 6.8 months, respectively. The difference between PFD measured at serial ultrasounds and the correlation with AI were analyzed.

RESULTS

The PFD increased significantly (p < 0.001) at serial measurements. The mean PFD at the first, second, and third ultrasounds were 3.3 (2.0-5.7), 4.3 (2.9-7.2), and 5.1 (3.3-8.0) mm, respectively. The PFD at three ultrasounds were all significantly (p < 0.001) and positively correlated with AI, with the Pearson correlation coefficients being 0.658, 0.696, and 0.753 for the first, second, and third ultrasounds, respectively. Using AI as reference, the diagnostic ability of PFD was calculated by the areas under the receiver operating characteristic curve, which was 0.845, 0.902, and 0.938 for the first, second, and third PFD, respectively. For the first, second, and third ultrasounds, PFD cutoff values of ≥ 3.9, ≥ 5.0, and ≥ 5.7 mm, respectively, yielded the greatest sensitivity and specificity in predicting late abnormal AI.

CONCLUSION

The PFD naturally progresses with age and is positively correlated with AI. The PFD has potential for predicting residual dysplasia. However, the cutoff for abnormal PFD values may require adjustment according to the patient's age.

KEY POINTS

• The pubofemoral distance measured in hip ultrasonography naturally increases as the infant's hips mature. • The early pubofemoral distance demonstrates a positive correlation with late acetabular index measurements. • The pubofemoral distance may help physicians predict abnormal acetabular index. However, the cutoff for abnormal pubofemoral distance values may require adjustment according to patient's age.

Implementing the AAOS Guidelines for Screening of Developmental Dysplasia of the Hip Before the Age of 6 Months in Taiwan

BACKGROUND

The prevalence of developmental dysplasia of the hip (DDH) has been considered to be low in East Asia, but this may be incorrect because of inconsistent diagnostic definitions and testing criteria. In 2015, the AAOS released guidelines for systematic screening for DDH in newborns. We implemented these guidelines and compared DDH incidence and outcomes before and after their implementation.

METHODS

We used a historic comparison cohort of newborns with DDH between July 2015 and May 2017 before guideline implementation (the preguideline group); their data were retrieved using electronic medical records. In this group, the newborns received general hip screening without systemic follow-up. The postguideline group included newborns who were screened for hip dysplasia and followed up per the AAOS guidelines between July 2017 and May 2019. Their data were prospectively collected. The primary outcome in the postguideline group was DDH incidence. Other outcomes included rates of referral, surgery, and complications, and DDH prognosis.

RESULTS

The preguideline and postguideline groups included 3534 and 2663 newborns, respectively, of whom 49 (1.1%) and 225 (8.4%), respectively, were referred to the pediatric orthopaedic clinic enrolled. In the postguideline group, 35 patients were diagnosed as having DDH (incidence: 1.3%, 95% CI: 0.8%-1.9%). Both the incidence and referral rates were significantly higher in the postguideline group than in the preguideline group. Furthermore, the mean age at referral was 6.7±10.06 months and 0.9±0.25 months in the preguideline and postguideline groups, respectively, indicating a potential for early treatment in the postguideline group. Finally, the female sex was identified as a risk factor for residual hip dysplasia at 6 months of age.

CONCLUSION

DDH incidence in East Asia seems comparable to that in Western countries. Implementing the AAOS guidelines increased the diagnosis rate and opportunity for early treatment initiation, thus potentially avoiding surgical intervention. Nevertheless, residual DDH may be detected in some patients at 6 months of age, particularly in female infants.

LEVEL OF EVIDENCE

Level IV.

Is double-crossed retrograde elastic stable intramedullary nailing an alternative method for the treatment of diaphyseal fractures in the adult humerus?

BACKGROUND

The aim of this study was to compare two techniques for the surgical treatment of diaphyseal fractures in the adult humerus: double-crossed retrograde elastic stable intramedullary nailing (DCR-ESIN) and limited-contact dynamic compression plate (LC-DCP).

METHODS

This was a retrospective study conducted at a single hospital. We included 122 patients with diaphyseal fractures of the humerus who had received DCR-ESIN or LC-DCP from January 2011 to January 2017. We compared union rates, union times, disabilities of the arm, shoulder, and hand (DASH) scores at the postoperative 1-year follow-up, and complications between the two groups.

RESULTS

Plating management was performed in 63 patients, while DCR-ESIN was performed in 59 patients. The union rate was higher in the DCR-ESIN group than in the LC-DCP group (100% vs. 90.5%; p = 0.052). The union time was shorter in the DCR-ESIN group than in the LC-DCP group (12.0 weeks vs. 14.8 weeks; p < 0.001). The intraoperative blood loss and operative time were less in the DCR-ESIN group than in the LC-DCP group (76.4 min vs. 129.5 min; p < 0.001; 60.9 ml vs. 244.8 ml; p < 0.001, respectively). The DCR-ESIN had superior results for the rate of overall complications (p = 0.006). At the 1-year follow-up, the DCR-ESIN group had better DASH scores than the LC-DCP group (p = 0.014).

CONCLUSIONS

The DCR-ESIN technique, used to treat diaphyseal fractures of the humerus, has shorter operative times, less intra-operative blood loss, shorter union times, and better functional outcomes at 1-year follow-up than the LC-DCP technique. DCR-ESIN may be an alternative method for the surgical treatment of diaphyseal humeral fractures in adults.

Association between early sonographic findings and acetabular index at the age of 6 months: a prospective observational study

Background

This study investigated the association between early Graf classification and femoral head coverage (FHC) with the acetabular index (AI) at the age of 6 months.

Methods

A prospective observational study was conducted between 2017–2018. Patients requiring Pavlik harness treatment and patients with syndromic dislocation or neurogenic dislocation were excluded. In total, 169 newborns with the first ultrasound performed at the mean age of 12.3 (0–15) days, the second ultrasound performed at the mean age of 3.2 (2.5–4.1) months, and the AI measured at the age of 6.6 (4.3–7.1) months were enrolled. The correlation between the AI and first and second alpha angles and FHC measurements, and the correlation of dysplasia in early ultrasound with dysplasia in the AI were analyzed.

Results

At the first ultrasound, only the FHC (P = .02) demonstrated a significant negative correlation with the AI. At the second ultrasound, both the alpha angle (P < .01) and FHC (P < .01) demonstrated a significant negative correlation with the AI. With the AI as a reference, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were found to be 77%, 7%, 5%, and 81%, respectively, for the first Graf; 91%, 37%, 9%, and 98%, respectively, for the first FHC measurement; 82%, 90%, 35%, and 99%, respectively, for the second Graf; and 95%, 97%, 68% and 99%, respectively, for the second FHC measurement.

Conclusions

FHC and alpha angle exhibited significant negative correlations with the AI at six months, both ultrasound parameters may have the potential to predict AI in DDH screening. Compared to the ultrasound measurements taken at 2 weeks, Graf and FHC at 3 months demonstrated superior sensitivity, specificity, PPV, and NPV to detect abnormal AI. The best timing to perform ultrasound examination may need further research.

[Mechanism of Potentilla discolor in treating UC by regulating mitochondrial autophagy]

To evaluate the therapeutic effect of Potentilla discolor on 2,4,6-trinitrobenzensulfonic acid(TNBS)-induced experimental ulcerative colitis(UC) in rats and to determine its therapeutic mechanism through mitochondrial autophagy, immune cells, and cytokines. A rat model of UC was established by TNBS-ethanol enema. Rats were divided into six groups: control, UC model, sulfasalazine(positive drug), and high-dose, moderate-dose, and low-dose ethanol extract groups. After 14-day continuous administration of the corresponding drugs, the disease activity index(DAI) and hematoxylin and eosin(HE) were evaluated. The morphological structure of mitochondria was observed by using transmission electron microscope(TEM), mitophagy-related mRNA expression was detected by using Real-time quantitative polymerase chain reaction(qRT-PCR), immune cell differentiation in rat serum was detected by using flow cytometry(FCM), and cytokine expression in colon tissues of rats was detected by protein microarray. The results showed that compared with the model group, each dose group of P. discolor could significantly reduce the DAI of UC model rats, and decrease the degree of inflammatory cells infiltration in the colon tissue of UC model rats. Meanwhile the expressions of T cells and Th cells in the serum increased significantly, the expression of Tc cells in the serum decreased significantly. Transmission electron microscope found that there was fusion of mitochondria and lysosomes in the colon tissue of the administration group. The expressions of mitochondrial autophagy related genes NF-κB, p62 and parkin were significantly increased in colon tissues. The results of protein chip showed that compared with the model group, the high dose group of P. discolor could significantly regulate the expression of cytokines. In conclusion, these results suggested that P. discolor improved TNBS-induced acute ulcerative colitis in rats by regulating the mitochondrial autophagy and the inflammatory factor expression.

Interobserver agreement and clinical disparity between the Graf method and femoral head coverage measurement in developmental dysplasia of the hip screening: A prospective observational study of 198 newborns

Ultrasonography is the ideal tool for assessing hip morphology in infants younger than 6-month-old. This study assessed the interobserver agreement and clinical disparities of the 2 most widely used ultrasound (US) methods, the Graf method, and femoral head coverage (FHC) measurement.A prospective observational study (STROBE compliant) of 2024 newborns was conducted between January 2017 and December 2018. Hip US was conducted on all newborns with abnormal Barlow and Ortolani maneuvers as well as on 50 randomly selected normal newborns. The physical examination and US were performed by a senior pediatric orthopedic surgeon with musculoskeletal sonography certification. Three observers with different levels of experience interpreted the images by using the Graf method and FHC. We analyzed the intraclass correlation coefficient, Cohen kappa, and the disparity between the clinical findings of the 2 methods.A total of 198 newborns (9.8%) presented with clinical instability, including 193 subluxatable hips in 168 patients (84.8%) and 45 dislocatable/dislocated hips in 30 patients (15.2%). The mean age at US examination was 11.69 days (range: 0-18 days). The intraclass correlation coefficient was .71 (95% CI: 0.55-0.83) for FHC, 0.63 (95% CI: 0.38-0.78) for the alpha angle, and 0.47 (95% CI: 0.16-0.69) for beta angle. The Cohen kappa coefficients of Graf type were 0.19 (95% CI: 0.03-0.35), 0.39 (95% CI: 0.20-0.58), and 0.17 (95% CI: 0.02-0.32) between observers 1 and 2, observers 1 and 3, and observers 2 and 3, respectively. Based on the Graf method, 14% of the stable hips had abnormal USs; by contrast, 19.2% of the subluxatable hips and 17.8% of the dislocatable/dislocated hips had normal Graf morphologies. In USs interpreted using FHC, 16% of stable hips demonstrated abnormal coverage, whereas 13.5% of subluxatable hips and 4.4% of dislocatable/dislocated hips had normal FHC.Incidence of clinically detectable hip instability was 9.8% among newborns in our series. Both alpha angle and FHC ratio revealed substantial interobserver agreement while beta angle achieved moderate agreement. FHC ratio possesses higher sensitivity and similar specificity compared with the Graf method when screening unstable hips.Level II, development of diagnostic criteria on basis of consecutive patients.

[Diversity and community characteristics of organic phosphate-mineralizing bacteria in the sea area between Minjiang Estuary to Pingtan.]

Microbial mineralization of organic phosphorus is an important component of marine phosphorus cycle. The research on organic phosphate-mineralizing bacteria (OPB) is helpful to reveal microbial driving mechanism of organic phosphorus mineralization in eutrophic sea area. The diversity and community characteristics of OPB were examined by Illumina high-throughput sequencing using the primer sets phoX in the sea area between Minjiang Estuary to Pingtan in April (spring) and July (summer) 2019. The results showed that the Shannon index of OPB in the surface seawater samples ranged from 3.21 to 7.91, and that the diversity at each station was greater in spring than that in summer. Shannon index of OPB in the sediment samples ranged from 2.04 to 8.70, which was greater in summer than that in spring. Shannon index of OPB in surface seawater of each station was higher than that of sediment in spring, while it was in adverse in summer. Nine phyla of OPB were detected in surface seawater, with Proteobacteria and Cyanobacteria being the most abundant. Tweleve phyla of OPB were detected in the sediments, with Proteobacteria and Bacteroidetes being the most dominant. OPB community composition at the genus level showed obvious spatio-temporal variation. Leisingera, Phaeobacter, Thalassococcus, and Pseudomonas were the major genera in the seawater in spring, while Synechococcus, Halioglobus, Roseovarius, Phaeo-bacter, Sulfitobacter, and Hyphomonas were the major genera detected in summer. Leisingera, Phaeobacter, Vibrio, and Sulfitobacter were major genera in the sediment in spring, while Azospirillum, Aminobacter, Sulfurifustis, Burkholderia, and Thiohalobacter were the major genera in summer. A large number of unclassified OPB were detected in both surface seawater and sediment. The redundancy analysis results showed that dissolved oxygen, water temperature, pH, dissolved inorganic nitrogen, NO₂^--N, and NO₃^--N had great influences on community distribution of OPB in the surface seawater. The abundant OPB in the surface seawater and sediment might play an important role in phosphorus cycle in this sea area.

Increased vasculogenesis of endothelial cells in hyaluronic acid augmented fibrin-based natural hydrogels - from in vitro to in vivo models

Vascularisation efficiency plays an essential role in the success of bulk transplantation, while biocompatibility and safety are major concerns in clinical applications. Fibrin-based hydrogels have been exploited as scaffolds for their advantages in biocompatibility, degradability and mass transportation in various forms. However, the mechanical strength and degree of vascularisation remain unsatisfactory for clinical usage. An interpenetrating hydrogel was developed by adding hyaluronic acid (HA) to a fibrin-based natural hydrogel. The vasculogenesis of endothelial cells (human umbilical vein endothelial cells, HUVECs) was characterised within the gel using both in vitro and in vivo animal studies. The in vitro vascular morphology analysis showed 17.9 % longer mean tube length and 14.3 % higher average thickness in 7 d cultivation within the HA-supplemented hydrogel. The in vivo results showed 51.6 % larger total tube area, 1.8 × longer average tube length and 81.6 % higher cell number in the HA-supplemented hydrogel compared to the hydrogel without HA. The experimental results demonstrated better vascularisation and cell recruitment in the HA- supplemented hydrogel. The material properties of the hydrogels were also analysed using atomic force microscopy (AFM). The results revealed 3.7 × higher elasticity of the HA-supplemented hydrogel, which provided better mechanical strength and support for easy handling during procedures. With the demonstrated advantages, the developed hydrogels showed promise for exploitation in various practical clinical applications.

[Imaging characteristics of patients with large vestibular aqueduct syndrome and its relationship with the acoustically evoked short latency negative response]

Objective: To explore the imaging characteristics of large vestibular aqueduct syndrome (LVAS) patients and their relationship with the acoustically evoked short latency negative response (ANSR), so as to provide reference for the diagnosis of LVAS. Methods: Clinical data of 174 patients(334 ears) with LVAS diagnosed and treated by the Department of Otorhinolaryngology Head and Neck Surgery of the First Affiliated Hospital of Guangxi Medical University, from October 2009 to December 2017 were retrospectively analyzed, including 117 males and 57 females, aged from 5 months to 47 years old, with the median age of 4 years and 4 months. ABR and imaging data of patients were collected. Midpoint diameter and the outlet diameter of the vestibular aqueduct were measured on CT images, the midpoint diameter of the intraosseous parts and the extraosseous parts of enlarged endolymphatic sac(EES) were measured on MRI images. The correlation between the above measurements was analyzed by Pearson test using SPSS 17.0. According to whether ASNR was detected in ABR, the above data were divided into two groups, and the differences of the above imaging measurements were compared by the Independent-Sample Test. Results: The average midpoint diameter of the vestibular aqueduct was (1.87±0.58) mm (x±s, the following was the same), and the outlet diameter was (3.07±0.99) mm on CT; the average midpoint diameter of the intraosseous parts in enlarged endolymphatic sac(EES) was (2.39±1.37) mm, and the extraosseous parts was (2.50±2.18) mm on MRI. There was a correlation between the four measurements (P<0.05), among which the midpoint diameter of vestibular aqueduct was strongly positively correlated with the outlet diameter (r=0.760), and the remaining pairs were weakly correlated. ASNR was detected in 241 ears (72.16%,241/334) and undetected in 93 ears (27.84%, 93/334) of the 334 ears with LVAS. Midpoint diameter and the outlet diameter of the vestibular aqueduct in no ASNR group were smaller than the ASNR group, and the difference was statistically significant (t value was 2.814 and 2.754, P<0.05). There was no significant difference in the midpoint diameter of the intraosseous parts and the extraosseous parts of enlarged endolymphatic sac between the two groups, and the difference was no statistically significant(t value was 0.101 and 0.683, P>0.05). Conclusions: There is a strong positive correlation between the midpoint diameter of vestibular aqueduct and the outlet diameter in LVAS patients. There is a certain correlation between the size of vestibular aqueduct and the size of endolymphatic sac. The smaller the diameter of vestibular aqueduct, the lower the occurrence rate of ASNR.

Radiographic risk factors for predicting failure of geriatric intertrochanteric fracture treatment with a cephalomedullary nail

BACKGROUND

The cephalomedullary nail is the most common device used to treat unstable intertrochanteric fractures (ITFs) (AO/OTA 31-A2 and A3) in the geriatric population. However, there is lack of radiological parameter to evaluate the entry point; hence, this study reports a new radiological parameter to evaluate the entry point of the nail. Besides, other risk factors were also examined.

METHODS

A retrospective study on the geriatric population with unstable ITFs was conducted from July 2011 to December 2014. A total of 136 patients were enrolled in this study; they received treatment with Gamma-3 nails (Stryker, Mahwah, NJ, USA) and were followed for at least 1 year. Demographic data, radiological parameters, and side-difference of the distance from the piriformis fossa to the greater trochanteric tubercle in the anteroposterior view (dPG) were compared between the union and failure groups. Student's t test, χ test, and multiple logistic regression were used in the statistical analyses.

RESULTS

The overall failure rate was 13.23% (18 patients). Sex, tip-apex distance (TAD), and dPG were significantly different between the failure and union groups in multivariate analyses. Using a dPG > 6 mm as a reference, patients with a dPG > 6 mm had an odds ratio of 7.64 for failure relative to a dPG < 6 mm.

CONCLUSION

This study provides additional evidence demonstrating that sex and TAD have significant effects on the outcomes of unstable ITFs after nailing. Moreover, the newly reported radiological parameter, dPG, can be used to predict the failure of ITFs treated using cephalomedullary nails.

The efficacy of a drug holiday test on two-stage revision for infected total knee arthroplasty

BACKGROUND

We compared the clinical efficacy of normal C-reactive protein (CRP) expression (<1.0 mg/dL), with a 2-week drug holiday test (DHT) and no drug holiday test (DHT) as a reimplantation criterion, based on subsequent infections after a two-stage revision of a total knee arthroplasty of a periprosthetic joint infection (PJI).

METHODS

In a 10-year review of 58 patients (mean age: 73.3-years-old; mean follow-up: 46.2 months), there were 31 patients in the DHT group and 27 patients in the DHT group. Primary outcome was recurrent infection rate. Secondary outcomes included length of hospital stay in the revision stage and CRP resurge one day before revision.

RESULTS

We reported that the CRP resurge rate in the DHT group (0%) was significantly (p = 0.029) lower than that in the DHT group (16.1%) one day before the revision. The DHT group also had a significantly shorter mean length of stay (LOS) in the hospital (9.6 vs 12.7 days, p = 0.015) and a nonsignificantly lower subsequent infection rate (14.8% vs 29%, p = 0.195).

CONCLUSION

We found that disciplined use of DHT as a reimplantation criterion reduced CRP resurges before reimplantation and yielded a shorter LOS afterward. DHT positively affected the subsequent mid-term infection rate after PJI treatment.

Kinect-based virtual rehabilitation and evaluation system for upper limb disorders: A case study

OBJECTIVE

To help patients with disabilities of the arm and shoulder recover the accuracy and stability of movements, a novel and simple virtual rehabilitation and evaluation system called the Kine-VRES system was developed using Microsoft Kinect.

METHODS

First, several movements and virtual tasks were designed to increase the coordination, control and speed of the arm movements. The movements of the patients were then captured using the Kinect sensor, and kinematics-based interaction and real-time feedback were integrated into the system to enhance the motivation and self-confidence of the patient. Finally, a quantitative evaluation method of upper limb movements was provided using the recorded kinematics during hand-to-hand movement.

RESULTS

A preliminary study of this rehabilitation system indicates that the shoulder movements of two participants with ataxia became smoother after three weeks of training (one hour per day).

CONCLUSION

This case study demonstrated the effectiveness of the designed system, which could be promising for the rehabilitation of patients with upper limb disorders.

Autoantibody against integrin αv β3 contributes to thrombocytopenia by blocking the migration and adhesion of megakaryocytes

Essentials The pathogenesis of immune thrombocytopenia (ITP) has not been fully clarified. We analyzed the role of anti-αvβ3 autoantibody in the pathogenesis of ITP in patients. Anti-αvβ3 autoantibody impeded megakaryocyte migration and adhesion to the vascular niche. Anti-αv β3 autoantibody potentially contributes to the pathogenesis of refractory ITP.

SUMMARY

Background The pathogenesis of immune thrombocytopenia (ITP) has not been fully clarified. Anti-αvβ3 integrin autoantibody is detected in chronic ITP patients, but its contribution to ITP is still unclear. Objectives To clarify the potential role of anti-αvβ3 integrin autoantibody in chronic ITP and the related mechanism. Methods Relationship between levels of anti-αvβ3 autoantibody and platelets in chronic ITP patients was evaluated. The influence of anti-αvβ3 antibody on megakaryocyte (MK) survival, differentiation, migration and adhesion was assessed, and the associated signal pathways were investigated. Platelet recovery and MKs' distribution were observed in an ITP mouse model pretreated with different antibodies. Result In this study, we showed that the anti-αvβ3 autoantibody usually coexists with anti-αIIbβ3 autoantibody in chronic ITP patients, and patients with both autoantibodies have lower platelets. In in vitro studies, we showed that the anti-αvβ3 antibody had no significant effect on the survival and proliferation of MKs, whereas it decreased formations of proplatelet significantly. Anti-αvβ3 antibody impeded stromal cell derived facor-1 alpha (SDF-1α)- mediated migration and inhibited the phosphorylation of protein kinase B. Anti-αvβ3 antibody significantly inhibited MKs' adhesion to endothelial cells and Fibrogen. The phosphorylation of focal adhesion kinase and proto-oncogene tyrosine-protein kinase Src induced by adhesion was inhibited when MKs were pretreated with anti-αvβ3 antibody. In in vivo studies, we showed that injection with anti-αv antibody delayed platelet recovery in a mouse model of ITP. Conclusions These findings demonstrate that the autoantibody against integrin αv β3 may aggravate thrombocytopenia in ITP patients by impeding MK migration and adhesion to the vascular niche, which provides new insights into the pathogenesis of ITP.

2 dyn/cm2 shear force upregulates kruppel-like factor 4 expression in human chondrocytes to inhibit the interleukin-1β-activated nuclear factor-κB

The shear force effect on human chondrocytes is time and magnitude dependent. Recently, kruppel-like factor (KLF) 4 has been identified as a pleiotropic protein and its activity in cells is dependent on different stimuli and/or cell types. The role of KLF4 in chondrocytes is still unclear and there has been no report determining whether shear force regulates KLF4 levels in chondrocytes. Hence, this study was carried out to investigate the role of KLF4 in human chondrocytes under shear force stimulation and the underlying mechanism. Human primary and SW1353 chondrocytes were used in this study. The shear forces at 2, 5, or 15 dyn/cm² intensity were applied to both types of human chondrocytes. The specific small interfering RNAs, activators, and inhibitors were used to study the detailed mechanism of shear force. The presented results showed that 2, but not 5 and 15, dyn/cm² shear force increases KLF4 expression in human primary and SW1353 chondrocytes. Extracellular signal-regulated kinase 5 induced peroxisome proliferator-activated receptor γ transcription activity to increase KLF4 transcription. Moreover, the KLF4 induction in human chondrocytes in response to 2 dyn/cm² shear force could attenuate interleukin (IL)-1β-stimulated nuclear factor-κB activation. These results elucidate the role of KLF4 in antagonizing the effect of IL-1β in human chondrocytes under 2 dyn/cm² shear force stimulation and provide a possible mechanism to demonstrate the protection of moderate forces or exercises in cartilage.

HLA-B*07, HLA-DRB1*07, HLA-DRB1*12, and HLA-C*03:02 Strongly Associate With BMI: Data From 1.3 Million Healthy Chinese Adults

Strong associations between HLA alleles and infectious and autoimmune diseases are well established. Although obesity is also associated with these diseases, the relationship between HLA and obesity has not been systematically investigated in a large cohort. In the current study, we analyzed the association of HLA alleles with BMI using data from 1.3 million healthy adult donors from the Chinese Marrow Donor Program (CMDP). We found 23 HLA alleles, including 12 low-resolution and 11 high-resolution alleles, were significantly associated with BMI after correction for multiple testing. Alleles associated with high BMI were enriched in haplotypes that were common in both Chinese and European populations, whereas the alleles associated with low BMI were enriched in haplotypes common only in Asians. Alleles B*07, DRB1*07, DRB1*12, and C*03:02 provided the strongest associations with BMI (P = 6.89 × 10^-10, 1.32 × 10^-9, 1.52 × 10^-9, and 4.45 × 10^-8, respectively), where B*07 and DRB1*07 also had evidence for sex-specific effects (P_{heterogeneity} = 0.0067 and 0.00058, respectively). These results, which identify associations between alleles of HLA-B, DRB1, and C with BMI in Chinese young adults, implicate a novel biological connection between HLA alleles and obesity.

Leptin induces MMP1/13 and ADAMTS 4 expressions through bone morphogenetic protein-2 autocrine effect in human chondrocytes

The induction of bone morphogenetic protein (BMP)2 in injured and arthritis articular cartilage has been proposed, but the precise mechanism has not been clearly clarified. Our previous study has found that leptin could stimulate the BMP2 autocrine effect to increase the anabolic collagen II expression when it initiates the catabolic response in human chondrocytes. It has been suggested that this BMP2 autocrine effect contributes to a reparative role in leptin-stimulated human chondrocytes. In this study, we further determined whether this BMP2 autocrine effect also affect the expressions of catabolic matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase with thrombospondin motif (ADAMTS). Human primary and SW1353 chondrocytes were used in this study. It was shown that leptin could induce the expressions of MMP1, 3, and 13 and ADAMTS4 and 5 in both human primary and SW1353 chondrocytes. Leptin-increased MMP1/13 (not MMP3) and ADAMTS4 (not ADAMTS5) expressions were affected by the leptin-upregulated BMP2 and its specific downstream Smad1/5 signaling. Moreover, both HDAC3 and 4 are involved in regulating leptin-induced BMP2 upregulation and then affect MMP1 and 13 and ADAMTS4 expression. Both HDAC3 and 4 also affect leptin-increased MMP3 mRNA expression but not through BMP2 autocrine effect of leptin induction. Our results further elucidated the role of BMP2 autocrine effect in matrix-degrading enzymes expressions under leptin stimulation. The findings in this study provide new insights into the possible mechanism of BMP2 induction in leptin-stimulated chondrocytes and in leptin-induced OA development.

[The effect and factors associated with outcome of extracorporeal membrane oxygenation in refractory cardiogenic shock patients]

Objective: To observe the clinical efficacy and factors associated with outcome of extracorporeal membrane oxygenation (ECMO) in refractory cardiogenic shock patients. Methods: Patients with refractory cardiogenic shock received ECMO treatment in our hospital from May 2013 to November 2015 were retrospectively analyzed. The clinical status before ECMO support, ECMO timing, complications and outcome were observed and analyzed.The hemodynamic data and the amount of vasoactive drugs at 2 hours before ECMO support and at 2, 6, 24 and 48 hours after ECMO support were collected and compared. Results: Ten refractory cardiogenic shock patients were included in this study (5 acute fulminant myocarditis patients, 4 acute myocardial infarction patients, 1 myocardial rupture patient (6 males, 4 females, age ranged 12 to 56 years). Before ECMO, the mean left ventricular ejection fraction (LVEF) was (31.4±10.2)%, the mean score of APACHE Ⅱ was 26.6±10.8. Eight patients developed cardiac arrests and the duration of CPR ranged from 10 to 300 minutes and three patients received IABP. CVP decreased, BP increased, HR decreased, ScVO₂ increased, dose of dobutamine decreased at 2 hours after ECMO support. After ECMO support for 6 hours, lactate decreased, dose of norepinephrine decreased. After ECMO support for 24 and 48 hours, hemodynamics became stable and shock was significantly improved. Complication including infection of limb and catheterization site occurred in 3 patients, femoral arterial thrombosis occurred in 2 patients, critical limb ischemia occurred in 2 patients, hemorrhage at the catheterization site occurred in 2 patients. The duration of ECMO ranged from 2 to 220 hours. Nine patients could be weaned off ECMO support and 6 patients survived to hospital discharge. Two patients died due to too late ECMO support, the other two patients died due to severe complication of limb. Conclusions: ECMO can rapidly improve hemodynamic stability of patients with cardiogenic shock. Accurate assessing the timing of ECMO support and decreasing complication of limb play a critical role on improving outcome in refractory cardiogenic shock patients.

Clinical and biophysical characterization of 19 GJB1 mutations

Objective

Charcot–Marie–Tooth disease type X1 (CMTX1), which is caused by mutations in the gap junction (GJ) protein beta‐1 gene (GJB1), is the second most common form of Charcot–Marie–Tooth disease (CMT). GJB1 encodes the GJ beta‐1 protein (GJB1), which forms GJs within the myelin sheaths of peripheral nerves. The process by which GJB1 mutants cause neuropathy has not been fully elucidated. This study evaluated the biophysical characteristics of GJB1 mutants and their correlations with the clinical features of CMTX1 patients.

Methods

All patients with a validated GJB1 mutation were assessed using the Charcot–Marie–Tooth disease neuropathy score version 2 (CMTNS). The impacts of the mutations on the biophysical functions of GJB1 were characterized by assessing intracellular localization, expression patterns, and GJ Ca²⁺ permeability.

Result

Nineteen GJB1 mutations were identified in 24 patients with a clinical diagnosis of CMT. Six are novel mutations: p.L6S, p.I20F, p.I101Rfs*8, p.F153L, p.R215P, and p.D278V. Diverse pathological effects of the mutations were demonstrated, including reduced GJB1 expression, intracellular mislocalization, and altered GJ functions. GJB1 mutations that caused a complete loss of GJ Ca²⁺ permeability appeared to be associated with an earlier disease onset, whereas those resulting in preservation of GJ permeability and with predominant cell membrane expression tended to have a later onset and a milder phenotype.

Interpretation

This study demonstrated that the degree of loss of GJ function caused by the GJB1 mutations might contribute to the onset and severity of neuropathic symptoms in CMTX1.

Fulvic Acid Attenuates Resistin-Induced Adhesion of HCT-116 Colorectal Cancer Cells to Endothelial Cells

A high level of serum resistin has recently been found in patients with a number of cancers, including colorectal cancer (CRC). Hence, resistin may play a role in CRC development. Fulvic acid (FA), a class of humic substances, possesses pharmacological properties. However, the effect of FA on cancer pathophysiology remains unclear. The aim of this study was to investigate the effect of resistin on the endothelial adhesion of CRC and to determine whether FA elicits an antagonistic mechanism to neutralize this resistin effect. Human HCT-116 (p53-negative) and SW-48 (p53-positive) CRC cells and human umbilical vein endothelial cells (HUVECs) were used in the experiments. Treatment of both HCT-116 and SW-48 cells with resistin increases the adhesion of both cells to HUVECs. This result indicated that p53 may not regulate this resistin effect. A mechanistic study in HCT-116 cells further showed that this resistin effect occurs via the activation of NF-κB and the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). Co-treating cells with both FA and resistin revealed that FA significantly attenuated the resistin-increased NF-κB activation and ICAM-1/VCAM-1 expression and the consequent adhesion of HCT-116 cells to HUVECs. These results demonstrate the role of resistin in promoting HCT-116 cell adhesion to HUVECs and indicate that FA might be a potential candidate for the inhibition of the endothelial adhesion of CRC in response to resistin.

Upregulation of Bone Morphogenetic Protein-2 Synthesis and Consequent Collagen II Expression in Leptin-stimulated Human Chondrocytes

Bone morphogenetic proteins (BMPs) play positive roles in cartilage development, but they can barely be detected in healthy articular cartilage. However, recent evidence has indicated that BMPs could be detected in osteoarthritic and damaged cartilage and their precise roles have not been well defined. Extremely high amounts of leptin have been reported in obese individuals, which can be associated with osteoarthritis (OA) development. The aim of this study was to investigate whether BMPs could be induced in human primary chondrocytes during leptin-stimulated OA development and the underlying mechanism. We found that expression of BMP-2 mRNA, but not BMP-4, BMP-6, or BMP-7 mRNA, could be increased in human primary chondrocytes under leptin stimulation. Moreover, this BMP-2 induction was mediated through transcription factor-signal transducer and activator of transcription (STAT) 3 activation via JAK2-ERK1/2-induced Ser727-phosphorylation. Of note, histone deacetylases (HDACs) 3 and 4 were both involved in modulating leptin-induced BMP-2 mRNA expression through different pathways: HDAC3, but not HDAC4, associated with STAT3 to form a complex. Our results further demonstrated that the role of BMP-2 induction under leptin stimulation is to increase collagen II expression. The findings in this study provide new insights into the regulatory mechanism of BMP-2 induction in leptin-stimulated chondrocytes and suggest that BMP-2 may play a reparative role in regulating leptin-induced OA development.

Cementless Acetabular Reconstruction for Arthropathy in Old Acetabular Fractures

This study was conducted to identify the factors influencing mechanical failure of cementless acetabular reconstruction for arthropathy after operative treatment of acetabular fractures. Fifty-six patients (56 hips) undergoing cementless total hip arthroplasty were enrolled and followed for a mean of 120 months (range, 60-180 months). The 10-year survival rate, with mechanical failure (radiographic loosening or revision due to aseptic loosening) as the endpoint, was analyzed with respect to sex, age, body mass index (BMI), acetabular bone deficiency, sclerotic changes to the acetabulum, and use of the Trabecular Metal (TM) cup (Zimmer, Inc, Warsaw, Indiana). Mean 10-year survival rates of the acetabular component were as follows: 80% (range, 65%-96%) in males and 100% in females (P=.032); 77% (range, 60%-95%) in patients younger than 50 years and 91% (range, 82%-100%) in older patients (P=.027); 88% (range, 78%-98%) in patients with a BMI less than 30 kg/m(2) and 81% (range, 74%-89%) in patients with a BMI of 30 kg/m(2) or higher (P=.068); 54% (range, 32%-76%) in patients manifesting large acetabular deficiency and 90% (range, 78%-100%) in the remaining patients (P<.001); 78% (range, 65%-91%) in patients with the presence of sclerotic acetabulum and 92% (range, 86%-100%) in patients with the absence of sclerotic acetabulum (P=.022); and 82% (range, 73%-100%) in patients who received a conventional shell and 100% in patients who received the TM cup (P=.039). Male sex, age younger than 50 years, large acetabular deficiency, and sclerotic changes of the acetabulum were significant factors contributing to the mechanical failure of cementless acetabular reconstruction performed for old acetabular fractures treated with open reduction and internal fixation. Use of the TM cup seemed able to prolong the endurance of the acetabular component in the subsequent reconstruction.

High-Resolution Analyses of Human Leukocyte Antigens Allele and Haplotype Frequencies Based on 169,995 Volunteers from the China Bone Marrow Donor Registry Program

Allogeneic hematopoietic stem cell transplantation is a widely used and effective therapy for hematopoietic malignant diseases and numerous other disorders. High-resolution human leukocyte antigen (HLA) haplotype frequency distributions not only facilitate individual donor searches but also determine the probability with which a particular patient can find HLA-matched donors in a registry. The frequencies of the HLA-A, -B, -C, -DRB1, and -DQB1 alleles and haplotypes were estimated among 169,995 Chinese volunteers using the sequencing-based typing (SBT) method. Totals of 191 HLA-A, 244 HLA-B, 146 HLA-C, 143 HLA-DRB1 and 47 HLA-DQB1 alleles were observed, which accounted for 6.98%, 7.06%, 6.46%, 9.11% and 7.91%, respectively, of the alleles in each locus in the world (IMGT 3.16 Release, Apr. 2014). Among the 100 most common haplotypes from the 169,995 individuals, nine distinct haplotypes displayed significant regionally specific distributions. Among these, three were predominant in the South China region (i.e., the 20^th, 31^st, and 81^sthaplotypes), another three were predominant in the Southwest China region (i.e., the 68^th, 79^th, and 95^th haplotypes), one was predominant in the South and Southwest China regions (the 18^th haplotype), one was relatively common in the Northeast and North China regions (the 94^th haplotype), and one was common in the Northeast, North and Northwest China (the 40^th haplotype). In conclusion, this is the first to analyze high-resolution HLA diversities across the entire country of China, based on a detailed and complete data set that covered 31 provinces, autonomous regions, and municipalities. Specifically, we also evaluated the HLA matching probabilities within and between geographic regions and analyzed the regional differences in the HLA diversities in China. We believe that the data presented in this study might be useful for unrelated HLA-matched donor searches, donor registry planning, population genetic studies, and anthropogenesis studies.

Progress of Diabetic Severity and Risk of Dementia

CONTEXT

Diabetes is a risk factor for dementia, but the effects of diabetic severity on dementia are unclear.

OBJECTIVE

The purpose of this study was to investigate the association between the severity and progress of diabetes and the risk of dementia.

DESIGN AND SETTING

We conducted a 12-year population-based cohort study of new-onset diabetic patients from the Taiwan National Health Insurance Research Database. The diabetic severity was evaluated by the adapted Diabetes Complications Severity Index (aDCSI) from the prediabetic period to the end of follow-up. Cox proportional hazard regressions were used to calculate the hazard ratios (HRs) of the scores and change in the aDCSI.

PARTICIPANTS

Participants were 431,178 new-onset diabetic patients who were older than 50 years and had to receive antidiabetic medications.

MAIN OUTCOME

Dementia cases were identified by International Classification of Diseases, ninth revision, code (International Classification of Diseases, ninth revision, codes 290.0, 290.1, 290.2, 290.3, 290.4, 294.1, 331.0), and the date of the initial dementia diagnosis was used as the index date.

RESULTS

The scores and change in the aDCSI were associated with the risk of dementia when adjusting for patient factors, comorbidity, antidiabetic drugs, and drug adherence. At the end of the follow-up, the risks for dementia were 1.04, 1.40, 1.54, and 1.70 (P < .001 for trend) in patients with an aDCSI score of 1, 2, 3, and greater than 3, respectively. Compared with the mildly progressive patients, the adjusted HRs increased as the aDCSI increased (2 y HRs: 1.30, 1.53, and 1.97; final HRs: 2.38, 6.95, and 24.0 with the change in the aDCSI score per year: 0.51-1.00, 1.01-2.00, and > 2.00 vs < 0.50 with P < .001 for trend).

CONCLUSIONS

The diabetic severity and progression reflected the risk of dementia, and the early change in the aDCSI could predict the risk of dementia in new-onset diabetic patients.

Concomitant hip and distal radius fractures

BACKGROUND

Concomitant ipsilateral hip and distal radius fractures are uncommon, and little research has been published about these injuries. Our aim was to evaluate the characteristics and results of treatment for these injuries.

METHODS

Between 2006 and 2012, 35 concomitant hip and distal radius fractures were identified, comprising the study group. The characteristics and results of treatment for these injuries were evaluated and analyzed. Another matched control group with isolated hip fractures was collected for comparison of patient characteristics, fall mechanism, fracture pattern, bone density, and functional recovery.

RESULTS

For the patients with concomitant fractures, the average age was 77.6 years, and the female-to-male ratio was 6:1 (30:5). The majority (91.4%) of patients sustained ipsilateral injuries. Among the controlled pairs, 20 (57.1%) patients in the study group sustained a backward fall, and 25 (71.4%) patients in the control group had a sideways fall. With respect to the pattern of hip fracture, 22 (62.9%) patients in the study group had femoral neck fractures and 20 (57.1%) patients in the control group had pertrochanteric fractures. The average hospital stay was 15.3 days in the study group versus 10.2 days in the control group. Twenty-five (71.4%) patients in the study group and 27 (77.1%) patients in the control group had osteoporosis. The average Barthel index score was 75.1 in the study group and 75.7 in the control group.

CONCLUSION

Concomitant hip and distal radius fractures were generally ipsilateral and involved the femoral neck after a backward fall. These patients were younger than and not more osteoporotic than the population with isolated hip fractures; however, the hospital stay was significantly increased. The functional outcome was not influenced by concomitant wrist fracture.

Impaired hematopoiesis and delayed thrombopoietic recovery following sublethal irradiation in SRC‑3 knockout mice

The objective of the present study was to investigate the role of the steroid receptor coactivator-3 (SRC-3) in hematopoiesis of mouse bone marrow (BM) following total body irradiation (TBI). SRC-3^−/− mice and wild-type (WT) mice were exposed to 4.5 Gy γ rays. Immunoblotting analysis revealed that the SRC-3 protein (p160) levels in normal BM-nucleated cells in WT were higher than in SRC-3^−/− mice. Furthermore, peripheral blood cell counts, BM cellularity and colony-forming unit (CFU) assays were performed following irradiation. The results showed that peripheral blood cells were significantly lower in number and recovered less rapidly in irradiated SRC-3^−/− mice as compared with control animals. BM-nucleated cell and CFU counts were significantly decreased in SRC-3^−/− mice on the 7th and 14th day. Of note, the recovery of platelet (PLT) and megakaryocytic lineage were more depressed than the granulocytic and erythroid lineage in SRC-3^−/− mice. In conclusion, the present study demonstrated that the hematopoietic ability in SRC-3 knockout mice is severely impaired following a sublethal dose of irradiation.

Concomitant tibial shaft and posterior malleolar fractures can be readily diagnosed from plain radiographs: A retrospective study

BACKGROUND

Concomitant tibial shaft and posterior malleolar fractures (PMFs) are often encountered in clinical settings. Plain films were reviewed for concomitant PMF, and fracture patterns were analyzed by focusing on the integrity of the fibula and the location of the fibular fracture.

METHODS

A retrospective review of patients who presented with tibial shaft fractures between January 2005 and January 2010 was performed. Patients were included if they were at least 18 years of age and had a tibial diaphyseal fracture. Exclusion criteria were age less than 18 years, previous surgery on the same leg, and pathological fractures. Medical records were reviewed for information on injury mechanisms. Pre- and post-operative radiographs were analyzed for PMFs, tibial fracture pattern, fibular integrity, fibular fracture pattern, treatment type, and time to fracture union. Descriptive statistical tests were used.

RESULTS

Among 240 patients, there were 20 cases (15 male and 5 female) of concomitant PMF, all detected in lateral radiograph views. The incidence of PMF was 8.3%. Most patients had a motorcycle injury (n = 15, 75%). Distal tibia spiral fracture was the most common fracture pattern (85%) and there was no proximal tibia fracture (0%). Combined fibular fractures were found in 17 patients (85%). There were nine proximal fibular fractures (45%). Intact fibulas were found in three patients (15%). Only one PMF was treated with screw fixation. All PMFs showed radiographic evidence of healing within 5 months post-operatively.

CONCLUSION

We recommend careful radiographic examination to evaluate PMF, especially in patients with distal tibial spiral fractures combined with proximal fibular fractures or intact fibulas.

Noncemented total hip arthroplasty for osteonecrosis of the femoral head in elderly patients

The results of total hip arthroplasty (THA) for osteonecrosis of the femoral head (ONFH) in elderly patients (80 years or older) has not been well defined. The purpose of this retrospective study was to evaluate the clinical course of and the results in noncemented THA for ONFH in elderly patients.Between 1998 and 2007, one hundred seven consecutive hips with ONFH in 103 patients were evaluated. The causes of ONFH were traumatic in 46 (43%) hips and nontraumatic in 61 (57%) hips. All hips were treated with noncemented THA. Average follow-up was 72 months (range, 60-144 months). The functional results improved to statistical significance after THA. However, no significant differences existed between 6 months, 1 year, and 5 years postoperatively. Nine (8.4%) postoperative complications occurred in these 107 hips, including 1 stem loosening, 1 liner wearing, 4 postoperative infections, 2 postoperative dislocations, and 1 pulmonary embolism. Fifteen (14.6%) deaths occurred during follow-up. The progression of ONFH in elderly patients was so rapid and the result of core decompression was so poor that a salvage procedure seemed to have no role in the treatment. Harris Hip Score, Short Form 36 physical function score, and Western Ontario and McMaster Universities Osteoarthritis Index scores significantly improved after noncemented THA. Ninety-two hips had a complete follow-up, and the survivorship of prosthesis was 95% (88/92) with minimal 5-year follow-up. Noncemented THA was effective in the treatment of ONFH in this group of patients.

Cerclage wiring in displaced associated anterior column and posterior hemi-transverse acetabular fractures

PURPOSE

The effects of cerclage wiring in the open reduction and internal fixation of displaced associated anterior column and posterior hemi-transverse acetabular fractures were evaluated.

METHODS

This is a retrospectively clinical study of such cases where the main surgical strategy was open reduction and internal fixation with cerclage wire and reconstruction plates. Data on 12 cases treated between 1992 and 2011 were collected. The mean follow-up period was 32 (12-132) months.

RESULTS

Reduction with a fracture gap of less than 2 mm without articular stepping and solid union was achieved in all 12 cases. Postoperative complication developed in one case of symptomatic arthritis. Excluding the case with symptomatic arthritis, the other cases had good to excellent final D'Aubigne and Postel functional results.

CONCLUSIONS

Cerclage wiring is very useful and effective in the reduction and fixation of displaced associated anterior column and posterior hemi-transverse acetabular fractures, and supplemental fixation with reconstruction plates and screws is necessary.

The role of autologous bone graft in surgical treatment of hypertrophic nonunion of midshaft clavicle fractures

BACKGROUND

This study was conducted to evaluate the results of treating hypertrophic nonunion of mid-shaft clavicle fracture with a limited contact dynamic compression plate (LC-DCP) without autologous cancellous bone graft.

METHODS

From 1995 to 2008, 51 cases of hypertrophic nonunion of mid-shaft clavicle fracture were managed with open reduction and internal fixation by LC-DCP without bone graft involvement. Of these 51 cases, 30 had nonunion after failure of initial surgical treatment (Group 1), and 21 had nonunion after failure of conservative treatment (Group 2). Preoperative and postoperative case management were the same for both groups, with the average follow-up period being 20.4 months (range 18-36). Our study evaluated the radiographic results and functional outcomes of these cases according to the quick disability of arm, shoulder, and hand score.

RESULTS

All 51 cases resulted in uneventful unions. There was no statistically significant difference between the two groups regarding patient demography, cause of injury, preoperative and postoperative functional scores, length of operation, union time, and duration of hospitalization (p>0.05).

CONCLUSION

LC-DCP fixation is an effective method for treating hypertrophic nonunion of mid-shaft clavicle fracture. Local bone graft is sufficient to achieve necessary union, and autologous bone graft from other sites of the body appears unnecessary.

Association of MICA gene polymorphisms with liver fibrosis in schistosomiasis patients in the Dongting Lake region

Major histocompatibility complex class I chain-related A (MICA) is a highly polymorphic gene located within the MHC class I region of the human genome. Expressed as a cell surface glycoprotein, MICA modulates immune surveillance by binding to its cognate receptor on natural killer cells, NKG2D, and its genetic polymorphisms have been recently associated with susceptibility to some infectious diseases. We determined whether MICA polymorphisms were associated with the high rate of Schistosoma parasitic worm infection or severity of disease outcome in the Dongting Lake region of Hunan Province, China. Polymerase chain reaction-sequence specific priming (PCR-SSP) and sequencing-based typing (SBT) were applied for high-resolution allele typing of schistosomiasis cases (N = 103, age range = 36.2-80.5 years, 64 males and 39 females) and healthy controls (N = 141, age range = 28.6-73.3 years, 73 males and 68 females). Fourteen MICA alleles and five short-tandem repeat (STR) alleles were identified among the two populations. Three (MICA*012:01/02, MICA*017 and MICA*027) showed a higher frequency in healthy controls than in schistosomiasis patients, but the difference was not significantly correlated with susceptibility to S. japonicum infection (Pc > 0.05). In contrast, higher MICA*A5 allele frequency was significantly correlated with advanced liver fibrosis (Pc < 0.05). Furthermore, the distribution profile of MICA alleles in this Hunan Han population was significantly different from those published for Korean, Thai, American-Caucasian, and Afro-American populations (P < 0.01), but similar to other Han populations within China (P > 0.05). This study provides the initial evidence that MICA genetic polymorphisms may underlie the severity of liver fibrosis occurring in schistosomiasis patients from the Dongting Lake region.

Patient controlled epidural analgesia for bilateral versus unilateral total knee arthroplasty: a retrospective study of pain control

BACKGROUND

Patient controlled epidural analgesia (PCEA) has been used commonly for postoperative pain management following total knee arthroplasty (TKA). The purpose of this study was to compare a single standardized PCEA protocol in patients who received unilateral TKA with patients who received simultaneous bilateral TKA.

METHODS

From October 2003 to October 2008, 912 patients were enrolled. Patient-machine interaction data were retrieved from PCA machines and stratified into 12 hour intervals. The data were analyzed according to the side of surgery, gender and methods of anesthesia. Patient demographic data, pain scores and side effect scores were compared to evaluate clinical efficacy.

RESULTS

There was no significant difference between the unilateral and bilateral TKA groups for pain scores, severity of side effects, and total drug use. However, there was a paradoxical increase in demand, delivery, and demand/delivery ratio of analgesics for unilateral rather than bilateral TKA. This was only noted in the first 12 hours. Both genders demanded more bolus doses than set by the standard protocol. Women with unilateral TKA received more delivery doses. All of the patients who received general anesthesia had a higher demand/delivery ratio while spinal anesthesia patients had no significant ratio difference.

CONCLUSION

PCEA provided equal analgesia for patients with unilateral or bilateral TKA. However, the paradoxical increase in demand suggested that psychological factors may play a role in pain perception. A comprehensive pain management program that addresses gender and anesthesia methods in the first 12 hours will improve clinical efficacy and patient satisfaction of PCEA.

Role of autologous bone graft in the surgical treatment of atrophic nonunion of midshaft clavicular fractures

A retrospective study was conducted to evaluate the role of autologous bone graft in treating atrophic nonunion of midshaft clavicle fracture with a limited-contact dynamic compression plate (LC-DCP). Between 1995 and 2008, sixty cases of atrophic nonunion of midshaft clavicle fractures were managed with open reduction and internal fixation with an LC-DCP. The cases were separated into 2 groups to evaluate the effect of autologous bone graft in the enhancement of bone union. In group 1 (n=24), autologous bone graft was not used; in group 2 (n=36), autologous bone graft was used. Pre- and postoperative management were the same in both groups. Radiographic results and functional outcomes according to the Quick Disability of Arm, Shoulder, and Hand score were evaluated. Average follow-up was 25.2 months (range, 24-48 months).No statistically significant difference was found between the 2 groups regarding demography and preoperative functional scores (P>.05). Operative time and hospital stay were statistically significant longer in group 2 (P<.001), and donor site pain was apparent in group 2. All 60 patients had uneventful union. No statistically significant differences were found between the 2 groups regarding union time (average, 9.8 weeks in group 1 and 9.2 weeks in group 2) and postoperative functional scores (P>.05). Limited-contact dynamic compression plate fixation is an effective method for treating atrophic nonunion of midshaft clavicle fractures. Autologous bone graft was not needed.

Comparison of articulating and static spacers regarding infection with resistant organisms in total knee arthroplasty

INTRODUCTION

The result of treatment of infections involving antibiotic-resistant organisms in total knee arthroplasty (TKA) is often poor. We evaluated the efficacy of 2-stage revision in TKAs infected with resistant organisms and compared the clinical outcomes with articulating and conventional static spacers, in terms of both infection control and function.

METHODS

In a prospective manner, from June 2003 to January 2007 selected patients with a TKA infected with resistant organisms were enrolled and treated with 2-stage re-implantation. The 45 patients were divided into 2 groups: group A (23 patients) implanted with the articulating spacers and group S (22 patients) implanted with static spacers. All patients followed the same antibiotic protocols and had the same re-implantation criteria. The efficacy of infection control was evaluated using re-implantation rate, recurrence rate, and overall success rate. The functional and radiographic results were interpreted with the Hospital of Special Surgery (HSS) knee score and the Insall-Salvati ratio.

RESULTS

With mean 40 (24-61) months of follow-up, 22 of 23 knees were re-implanted in group A and 21 of 22 were re-implanted in group S. Of these re-implanted prostheses, 1 re-infection occurred in group A and 2 occurred in group S. Range of motion after re-implantation, the final functional scores, and the satisfaction rate were better in group A. One third of the patients in group S, and none in group A, had a patella baja.

INTERPRETATION

After 2-stage re-implantation of TKAs originally infected with resistant organisms, the clinical outcome was satisfactory-and similar to that reported after treatment of TKAs infected with low-virulence strains. Treatment with an articulating spacer resulted in better functional outcome and lower incidence of patella baja.

An alternative solution to achieve primary stability in cementless revision hip arthroplasty for femur ectasia

BACKGROUND/PURPOSE

Revision total hip arthroplasty is technically demanding, especially when treating a large defective femur. The aim of this study was to evaluate the clinical results of cementless total hip arthroplasty revision in patients with advanced femoral bony defects.

METHODS

By using the canaloplasty technique, which osteotomized the proximal femur to reduce the width of canal, 12 patients were enrolled and underwent revision operation. Patients were evaluated by radiographic examination and Harris hip score before and after the index procedures.

RESULTS

The average length of follow-up was 38.7 months. All the osteotomies united at a mean of 5.3 months. Structural allografts were used on six patients to augment the thinned cortices. A total of 11 femoral components (91%) achieved and maintained stability at the last follow-up. One patient was complicated with early stem subsidence and another with deep infection. Both patients were treated successfully without late sequelae. The mean Harris hip score improved from 37.2 to 75.0 after the operation (p < 0.05).

CONCLUSION

The canaloplasty technique could be an alternative solution to help revision surgery in some younger patients with advanced femoral defects.

Displaced femoral neck fractures in young adults treated with closed reduction and internal fixation

This article describes the effect of closed reduction and internal fixation with 3 different screw configurations for acute completely displaced femoral neck fractures in young adults. From 2001 to 2006, 136 patients (age range, 20-50 years) who had acute unilaterally completely displaced femoral neck fractures were evaluated retrospectively. All fractures were managed with closed reduction and internal fixation with 3 cannulated screws. The follow-up period was 55 months on average (range, 36-90 months). One hundred twenty-two patients were available for final evaluation of union condition and late complication. Twenty-three patients (18.9%) had nonunion, 15 (12.3%) had fixation failure, and 21 (17.2%) had avascular necrosis of the femoral head. The average duration from injury to surgery was 18.4 hours in the union group and 23.3 hours in the nonunion group, with no statistical significance (P=.196). The average duration from injury to surgery was 17.3 hours in the avascular necrosis of the femoral head group and 22.3 hours in the non-avascular necrosis of the femoral head group, with no statistical significance (P=.155). Vertical- and separated-type screw configurations resulted in a significantly higher nonunion rate (P=.001 and P=.0017, respectively) than parallel configuration. The complication rate in treating completely displaced femoral neck fractures with internal fixation in young adults is high, and screw configuration may further affect results.

The effects of axial displacement on fracture callus morphology and MSC homing depend on the timing of application

The local mechanical environment and the availability of mesenchymal stem cells (MSC) have both been shown to be important factors in bone fracture healing. This study was designed to investigate how the timing of an applied axial displacement across a healing fracture affects callus properties as well as the migration of systemically introduced MSC. Bilateral osteotomies were created in male, Sprague-Dawley rats. Exogenous MSC were injected via the tail vein, and a controlled micro-motion was applied to one defect starting 0, 3, 10, or 24 days after surgery. The results showed that fractures stimulated 10 days after surgery had more mineral, less cartilage, and greater mechanical properties at 48 days than other groups. Populations of MSC were found in osteotomies 48 days after surgery, with the exception of the group that was stimulated 10 days after surgery. These results demonstrate that the timing of mechanical stimulation affects the physical properties of the callus and the migration of MSC to the fracture site.

A facile technique to make articulating spacers for infected total knee arthroplasty

BACKGROUND

To treat total knee arthroplasty, 2-stage revision, including removal and reimplantation, remains the standard treatment for the infected arthroplasty. Articulating cement spacer has been shown to provide better functional results after reimplantation. However, its cost as a manufactured product is not always easily affordable and the choice of antibiotics is not flexible either. The authors have developed a method for surgeons to make cement-on-cement articulating spacers themselves by using an impression-taking technique with polydimethyl siloxane. The current study was conducted to test their clinical efficacy.

METHODS

Fifteen patients with infected total knee arthroplasties were prospectively treated with 2-stage revision using articulating spacers made by this technique. The clinical assessment included intraoperative finding, surgical records, radiographic and laboratory examination and final functional scores. All the patients were regularly followed-up.

RESULTS

Fourteen of the 15 patients (93.3%) had infection eradicated, of which 13 patients received revision arthroplasty successfully. The average interval between the resection arthroplasty and the final procedure was 3.5 months. During this period, most of the patients could sit comfortably with bent knees and walk with partial weight-bearing. No patients had secondary bone loss. The range of motion after revision surgery achieved an average of 110 degrees. The average Hospital for Special Surgery score was 90.5 points, and none had recurrent infection after an average of 47.5 months of follow-up.

CONCLUSION

Treating infected total knee arthroplasty with these self-made articulating spacers eradicates infection effectively, improves the life quality before reimplantation and provides good final results without significant complications.

Slotted acetabular augmentation in the treatment of painful residual dysplastic hips in adolescents and young adults

BACKGROUND/PURPOSE

This study retrospectively evaluated the benefits and prognostic factors of slotted acetabular augmentation (SAA) used for treating painful residual or neglected dysplastic hips in adolescents and young adults.

METHODS

Sixteen hips in 15 patients underwent SAA at an average age of 14.4 years. The radiologic and functional outcomes were reviewed after an average follow-up of 6.6 years.

RESULTS

All the patients obtained marked alleviation of pain (p<0.05). Harris hip score (HHS) was improved from 74.7 to 92.7 on average (p<0.05). Postoperative center-edge angle, Sharp's angle, c/b ratio and femoral head coverage showed significant improvement (p<0.01). Among the radiographic parameters, only the postoperative measurement of the femoral head coverage was significantly correlated with improvement of HHS (p<0.05). Detectable progression of osteoarthritis, from grade III to IV, was found in one patient 12 years after surgery. None of the hips required conversion to joint replacement. There were no surgical complications. Three-dimensional computed tomography showed that the grafts remained intact and provided congruent coverage at the latest follow-up, and none of them required arthroplasty.

CONCLUSION

The major benefit of SAA was to alleviate hip pain by increasing load-bearing area. This benefit was not sensitive to preoperative radiographic parameters. There were no postoperative complications. Compared with other complex reconstructive acetabuloplasty procedures, SAA is a simple, safe and effective pain-reducing procedure for symptomatic dysplastic hips in adolescents and young adults.

Periprosthetic femoral supracondylar fracture after total knee arthroplasty with navigation system

We report 1 patient with a supracondylar periprosthetic fracture 1 month after computer-assisted total knee arthroplasty. The fracture line extended from previous anchoring pinholes into the supracondyle area. Intramedullary nailing of the left femur was performed under close reduction. The possible complication of pinhole fracture to total knee arthroplasty with navigation system should be kept in mind.

28-Day oral toxicity study of the aqueous extract from spider brake (Pteris multifida Poiret) in rats

Spider brake (Pteris multifida Poiret) is a very important folk herb and a constituent in most of the traditional herbal beverage formulas in Taiwan; however, little toxicological information is available regarding the safety following repeated exposure. The present study was conducted to evaluate the toxicity of aqueous extract from spider brake (SB) in Sprague-Dawley rats on dietary oral gavage at concentrations of 100, 500, and 1000 mg/kg b.w. day for 28 days. There were no adverse effects on general condition, growth, feed and water consumption, feed conversion efficiency, red blood cell and clotting potential parameters, clinical chemistry values, and organ weights except for neutrophils and lymphocytes being slightly diminished in male and female rats at the highest dose, respectively. Necropsy and histopathology findings revealed no treatment-related changes in any of the organs. The results obtained in this study allowed us to conclude that the SB properly utilized in the traditional oral administration could be devoid of any toxic risk.

Successful Treatment of Congenital Pseudarthrosis of the Tibia with Long Segment Fibular Allografting in a Young Child

Congenital pseudarthrosis of the tibia (CPT) in young children with large bone defect after surgical resection can be difficult to reconstruct. Structural allograft may be a useful alternative in such cases but data are limited. We report a girl 1 year and 10 months of age with CPT successfully treated with en bloc resection of there current extensive pseudarthrosis, intramedullary rod placement, and long-segment intercalary allografting with supplemental autograft of the bony defect. At 6 years of follow-up, radiographs showed equal leg lengths, with good incorporation into the host bone. This method is technically simple and less time-consuming. It may be considered as an alternative method to the other more complicated procedures, such as microvascular fibula graft or the Ilizarov technique, in such a young child.

Giant cell tumors of the knee: subchondral bone integrity affects the outcome

From January 1992 to July 2001, we treated 38 patients with giant cell tumour in the knee region. Seventeen tumours were located in the distal femur and 21 in the proximal tibia . Twenty patients were classified as Campanacci grade II, 15 as grade III, and three as grade I. Patients' mean age was 34.5 (19-65) years, and the mean follow-up was 52 (24-134) months. Operative procedures were chosen according to the extent of bone and soft-tissue involvement. In 28 patients, intralesional curettage and bone grafting was performed and in ten patients a wide resection. We defined subchondral bone of the knee to be affected when the distance to the tumour was less than 3 mm. We then measured the area of affected subchondral bone radiographically using plain radiographs, CT, and MRI. In patients initially treated with curettage and bone grafting, the mean area of initially affected subchondral bone was 18.6 (0-81)%. The mean Enneking functional score at follow-up was 88 (66.6-100). There was a linear trend showing that the larger the area of affected subchondral bone, the worse the functional score. Among patients initially treated with wide resection, the mean area of affected subchondral bone was 68.2 (41-100)%. There was, however, no significant association between affected subchondral bone area and functional score.

Periacetabular giant cell tumor treated with intralesional excision and allograft reconstruction

Giant cell tumors of the acetabulum are uncommon lesions. Their diagnosis is often delayed due to their slow progression, late onset symptoms and easily been obscured by bowel gas in plain pelvic radiographs. The tumor size is always very large at the time of diagnosis, with major nerve and joint involvement. Management of such tumor remains challenging to orthopedic surgeons. Between 1992 and 1999, 3 acetabular giant cell tumors were diagnosed and managed at our institution. The treatment modality was intralesional tumor excision with structural allograft reconstruction. The margin of tumor was routinely managed with high-speed burring and phenol application. All 3 patients were free of local recurrence at a mean follow-up of 89 months. Postoperative palsy of sciatic nerve occurred in 1 patient, but no complications such as wound infection or fracture were seen. The nerve palsy recovered completely 1 year later. The final functional outcome of the 3 patients was excellent. The result appears that intralesional excision with adjuvant therapy is feasible in the management of giant cell tumor of the acetabulum and is able to obtain a satisfactory outcome.

Giant-cell tumors of bone: an analysis of 87 cases

We reviewed 87 patients with giant-cell tumor treated between 1992 and 2001. The mean follow-up was 62 (28-138) months. Fifty-six lesions were treated with intralesional curettage with adjunctive phenol treatment and reconstructed with autograft and allograft. Thirty-one lesions were treated with wide resection and reconstructed with prosthesis, osteochondral allograft, or alloprosthetic composite. Overall recurrence was 12%. Recurrence rate after curettage was 18% and 3% after wide excision. Complication rate after wide excision was higher than that after curettage. Functional outcome was evaluated using the Enneking scoring system. Average rating was 86% for the lower extremity and 83% for the upper extremity. The overall satisfactory rate was 88%.