Presenting dual-functional peptides on implant surface to direct in vitro osteogenesis and in vivo osteointegration.

The complex biological process of osseointegration and the bio-inertness of bone implants are the major reasons for the high failure rate of long-term implants, and have also promoted the rapid development of multifunctional implant coatings in recent years. Herein, through the special design of peptides, we use layer-by-layer assembly technology to simultaneously display two peptides with different biological functions on the implant surface to address this issue. A variety of surface characterization techniques (ellipsometry, atomic force microscopy, photoelectron spectroscopy, dissipation-quartz crystal microbalance) were used to study in detail the preparation process of the dual peptide functional coating and the physical and chemical properties, such as the composition, mechanical modulus, stability, and roughness of the coating. Compared with single peptide functional coatings, dual-peptide functionalized coatings had much better performances on antioxidant, cellular adhesion in early stage, proliferation and osteogenic differentiation in long term, as well as in vivo osteogenesis and osseointegration capabilities. These findings will promote the development of multifunctional designs in bone implant coatings, as a coping strategy for the complexity of biological process during osteointegration.

PPAR γ activation in chondrocytes alleviates glucocorticoid-induced oxidative stress, mitochondrial impairment, and pyroptosis via autophagic flow enhancement.

Osteoarthritis (OA) is a progressive age-related disease characterised by pathological changes in the synovium, articular cartilage, and subchondral bone, significantly reducing the patients' quality of life. This study investigated the role of glucocorticoids, specifically dexamethasone, in OA progression, with a particular focus on their effects on chondrocytes. Although glucocorticoids are commonly used for OA pain relief, our research demonstrated that high concentrations of dexamethasone may accelerate OA progression by enhancing the ability of reactive oxygen species to inhibit chondrocyte autophagy, resulting in cell death and accelerated cartilage degeneration. Despite reports on the acceleration of pathogenesis and cartilage damage in some patients of OA taking corticosteroids, the mechanism behind the same has not been investigated. This necessitates an investigation of the concentration-dependent changes in the cartilage cells upon dexamethasone administration. In addition, the protective effect of PPAR γ on chondrocytes can prevent the decrease in chondrocyte autophagy and delay cartilage degeneration. Therefore, our study suggests that the therapeutic use of glucocorticoids in OA treatment should be more nuanced considering their potential detrimental effects. Future investigations should focus on the mechanisms underlying the glucocorticoid-mediated modulation of cell death processes, which could provide insights into new therapeutic strategies for OA treatment.

Formononetin inhibits IL-1ß-induced inflammation in human chondrocytes and slows the progression of osteoarthritis in rat model via the regulation of PTEN/AKT/NF-κB pathway.

BACKGROUND/AIM: Osteoarthritis (OA) is a common degenerative disease characterized by cartilage degradation and inflammation. This study aimed to investigate the anti-inflammatory properties of formononetin, an isoflavone extracted from astragalus membranaceus, on OA. METHODS: Human OA chondrocytes were pretreated in vitro with formononetin and subsequently stimulated with IL-1ß. The production of inflammatory mediators, cytokines and the synthesis of catabolic factors were evaluated by ELISA and Western blot analysis. In addition, a rat model of OA was established and treated with formononetin. RESULTS: Formononetin attenuated the overproduction of inflammatory mediators and cytokines, suppressed the expression of cyclooxygenase-2 and inducible nitric oxide synthase, and inhibited the synthesis of catabolic factors such as MMPs and thrombospondin motifs 5. Furthermore, formononetin exerted protective effects in a rat model of OA. Mechanistically, we found that formononetin inhibited IL-1ß induced activation of nuclear factor kappa B and AKT by activating the phosphatase and tensin homolog. CONCLUSIONS: Formononetin could be used as a potential agent for OA treatment.

Piceatannol suppresses inflammation and promotes apoptosis in rheumatoid arthritis­fibroblast­like synoviocytes by inhibiting the NF­κB and MAPK signaling pathways.

Rheumatoid arthritis (RA) is a chronic inflammatory disease that mainly targets the synovial membrane, thus causing stiffness, deformity and dysfunction of joints. To date, no effective anti­inflammatory treatments are available for RA. Piceatannol (PIC) is a natural derivative of resveratrol, which has been reported to attenuate the inflammatory response. To evaluate the effect of PIC on RA and to determine the underlying molecular target of PIC, both in vitro and in vivo experiments were performed in the present study. A CIA rat model was established to evaluate the therapeutic effects of PIC. TNF­α, IL­1ß and IL­6 levels in blood were measured by ELISA. Western blotting, immunofluorescence analysis and reverse transcription­quantitative PCR (RT­qPCR) were used to analyze the expression levels of protein and mRNA. In vitro, RA­fibroblast­like synoviocytes (FLSs) were pretreated with PIC and subsequently stimulated with TNF­α. The results revealed that PIC significantly upregulated the expression levels of proapoptotic proteins such as Bax and cleaved caspase­3. PIC also significantly reduced the production of proinflammatory cytokines, including PGE2, IL­6 and IL­1ß, and significantly downregulated the expression of cyclooxygenase­2 at both the mRNA and protein expression levels. Furthermore, PIC downregulated the expression of MMP­3 and MMP­13, which have been found to be highly expressed in the synovium of patients with RA. Mechanistically, PIC was capable of significantly downregulating the expression levels of proteins involved in the NF­κB and MAPK signaling pathways. The results of the in vivo experiments using a rat collagen­induced arthritis model demonstrated that PIC decreased the arthritis score and exerted beneficial effects in cartilage and significantly reduced the expression of MMP­13. In conclusion, the findings of the present study revealed that PIC could suppress the inflammatory response, promote apoptosis, and exert a significant regulatory effect on the NF­κB and MAPK signaling pathways in RA­FLSs. Therefore, PIC may represent a potential drug for the future treatment of RA.

Sparstolonin B suppresses free fatty acid palmitate-induced chondrocyte inflammation and mitigates post-traumatic arthritis in obese mice.

Abnormal lipid metabolism, such as systemic increased free fatty acid, results in overproduction of pro-inflammatory enzymes and cytokines, which is crucial in the development of obesity-related osteoarthritis (OA). However, there are only a few drugs that target the lipotoxicity of OA. Recent researches have documented that the traditional Chinese medicine, Sparstolonin B (Ssn B), exerted anti-inflammatory effects in various diseases, but not yet in OA. On the basis of this evidence, our works purposed to evaluate the effect of Ssn B on free fatty acid (FFA) palmitate (PA)-stimulated human osteoarthritic chondrocytes and obesity-associated mouse OA model. We found that Ssn B suppressed PA-triggered inflammatory response and extracellular matrix catabolism in a concentration-dependent approach. In vivo, Ssn B treatment inhibited cartilage degeneration and subchondral bone calcification caused by joint mechanical imbalance and alleviated metabolic inflammation in obesity. Mechanistically, co-immunoprecipitine and molecular docking analysis showed that the formation of toll-like receptor 4 (TLR4)/myeloid differentiation protein-2 (MD-2) complex caused by PA was blocked by Ssn B. Subsequently, it leads to inactivation of PA-caused myeloid differentiation factor 88 (MyD88)-dependent nuclear factor-kappaB (NF-κB) cascade. Together, these findings demonstrated that Ssn B is a potential treatment agent for joint degenerative diseases in obese individuals.

The use of 2-octyl cyanoacrylate as an adjuvant to wound closure in total knee arthroplasty.

PURPOSE: The efficacy of the use of 2-octyl cyanoacrylate (OCA) as an adjuvant to wound closure in preventing wound complications after total knee arthroplasty (TKA) is rarely reported. This study was aimed to determine whether the use of OCA as a supplement to conventional wound closure reduces the incidence of wound complications following TKA. PATIENTS AND METHODS: This retrospective study reviewed 1106 consecutive patients who underwent TKA for symptomatic end-stage osteoarthritis (OA) between 2012 and 2017. The first 562 patients who did not receive OCA were grouped into the Control group, and the subsequent 544 patients who received OCA as an adjuvant to wound closure were grouped into the OCA group. All patients were followed up for at least 2 years. The main outcome was the development of operative site complications, including aseptic and infectious complications. Aseptic wound complications were wound leakage, hematoma, wound dehiscence and delayed wound healing, and infectious complication was mainly referred to the superficial infection. RESULTS: No significant difference with regard to hematoma was observed between groups (3.0% vs. 3.7%, P = 0.617, φ = - 0.02). The incidences were significantly higher in the Control group versus the OCA group in regard to wound leakage (9.4% vs. 2.0%, P = 0.000, φ = 0.16), wound dehiscence (5.7% vs. 1.3%, P = 0.000, φ = 0.12), delayed wound healing (4.4% vs. 1.5%, P = 0.004, φ = 0.09) and superficial infection (2.0% vs. 0.4%, P = 0.022, φ = 0.07). No serious adverse events (AEs) occurred. CONCLUSIONS: The present study showed that the addition of OCA reduced the incidence of wound leakage, wound dehiscence, delayed wound healing and superficial infection after TKA compared to conventional wound closure. Based on the outcomes above, we decide to use OCA routinely for wound closure after TKA. LEVEL OF EVIDENCE: III, retrospective, cohort study.

Role of intra-wound powdered vancomycin in primary total knee arthroplasty.

BACKGROUND: No study has evaluated the effect of topical powdered vancomycin in patients undergoing primary total knee arthroplasty (TKA). The goal of this study is to determine if this method reduces postoperative infection rates following primary TKA. PATIENTS AND METHODS: This retrospective study reviewed 855 consecutive patients undergoing TKA. The first 418 patients, who did not receive topical vancomycin, were grouped into the control group and the subsequent 437 patients, who received powdered vancomycin applied to the target joint prior to wound closure, were grouped into the treatment group. RESULTS: The control group was found to have 18 infectious complications (4.3%) compared with 6 (1.4%) in the treatment group, which differed significantly (p<0.05). When comparing the rates of infectious complications independently, there was no significant difference in the rate of superficial infection (3.1% vs. 1.4%; p>0.05), while the difference in prevalence of periprosthetic joint infection (PJI) was statistically significant (1.2% vs. 0; p<0.05). No serious adverse events (AEs) occurred. DISCUSSION: Topical application of powdered vancomycin may present a reasonable means of decreasing the risk of infectious complications following TKA. There were no serious AEs associated with topical vancomycin. Further research is needed to focus on its long-term efficacy and safety. LEVEL OF EVIDENCE: III, retrospective, cohort study.

Pharmacological blockade of PCAF ameliorates osteoarthritis development via dual inhibition of TNF-α-driven inflammation and ER stress.

BACKGROUND: Epigenetic mechanisms have been reported to play key roles in osteoarthritis (OA) development. P300/CBP-associated factor (PCAF) is a member of the histone acetyltransferases, which exhibits a strong relationship with endoplasmic reticulum (ER) stress and transcription factor nuclear factor kappa B (NF-κB) signals. Salidroside, a natural histone acetylation inhibitor, showed its anti-inflammatory and anti-apoptotic effects in lipopolysaccharide (LPS)-stimulated microglia cells in our previous study. However, whether Sal has a protective effect against OA remains unknown, and its relationships to PCAF, NF-κB, and the ER stress pathway should be explored further. METHODS: We identified the role of PCAF in the pathogenesis of OA and determined the chondroprotective effect of Sal on both tumor necrosis factor alpha (TNF-α)-treated human chondrocytes and a destabilized medial meniscus (DMM) mouse OA model. FINDINGS: We found increased PCAF expression in human OA cartilage and TNF-α-driven chondrocytes. Meanwhile, silencing of PCAF attenuated nuclear p65 and C/EBP homologous protein levels in chondrocytes upon TNF-α stimulation. Furthermore, Sal was found to specifically bind to the inhibitory site of the PCAF protein structure, which subsequently reversed the TNF-α-induced activation of NF-κB signal and ER stress-related apoptosis in chondrocytes. In addition, the protective effect of Sal and its inhibitory effects on PCAF as well as inflammatory- and ER stress-related markers were also observed in the mouse DMM model. INTERPRETATION: Pharmacological blockade of PCAF by Sal ameliorates OA development via inhibition of inflammation and ER stress, which makes Sal a promising therapeutic agents for the treatment of OA.

Peiminine inhibits the IL-1ß induced inflammatory response in mouse articular chondrocytes and ameliorates murine osteoarthritis.

Osteoarthritis (OA) is a common arthrosis characterized by degeneration and inflammation of articular cartilage. In recent decades, peiminine (Pm) has been identified as one of the active ingredients of Fritillaria plants. According to reports, Pm has a potent anti-inflammatory effect in various diseases. However, the effectiveness of Pm as an anti-inflammatory in OA has not previously been reported. This research aims to evaluate the anti-inflammatory effect of Pm on interleukin (IL)-1ß-induced mice chondrocytes and its chondroprotective effect in a mouse OA model with surgical destabilization of the medial meniscus. IL-1ß-induced expression of nitric oxide (NO), prostaglandin E2 (PGE2), cyclooxygenase-2 (COX-2), tumor necrosis factor alpha (TNF-α), inducible nitric oxide synthase (iNOS) and interleukin-6 (IL-6) were all inhibited significantly by Pm pretreatment in vitro. In addition, Pm also inhibited the expression of thrombospondin motifs 5 (ADAMTS-5) and matrix metalloproteinase-13 (MMP-13), which are responsible for the degradation of the extracellular matrix (ECM). Additionally, the degradation of aggrecan and collagen II was reversed by Pm. Furthermore, Pm inhibited Akt phosphorylation and the nuclear transfer of nuclear factor-κB (NF-κB) and activated Nrf2/HO-1 signaling pathways both in vitro and in vivo. These findings suggested that Pm alleviated inflammatory effects in the IL-1ß-induced chondrocytes. Therefore, Pm might be a potential therapeutic agent for OA.

A new technique for medial-end comminuted clavicle fractures.

Fractures of the medial comminuted clavicle are rare injuries but are associated with significant morbidity and mortality. Although rare, such injuries deserve rapid diagnosis and effective treatment to avoid future complications. An optimal, standardized operative treatment has not yet been established. We presented a medial-end comminuted clavicle fracture and demonstrated successful results using a bridging plate technique across the sternum maintaining reduction and achieving union. We aim to provide an alternative technique to fix a displaced periarticular medial clavicle fracture, which we believe is simple, safer and promising.

Hypoxia preconditioning promotes bone marrow mesenchymal stem cells survival by inducing HIF-1α in injured neuronal cells derived exosomes culture system.

Bone marrow derived stem cells (BMSCs) transplantation are viewed as a promising therapeutic candidate for spinal cord injury (SCI). However, the inflammatory microenvironment in the spinal cord following SCI limits the survival and efficacy of transplanted BMSCs. In this study, we investigate whether injured neuronal cells derived exosomes would influence the survival of transplanted BMSCs after SCI. In order to mimic the microenvironment in SCI that the neuronal cells or transplanted BMSCs suffer in vivo, PC12 cells conditioned medium and PC12 cell's exosomes collected from H2O2-treated PC12 cell's culture medium were cultured with BMSCs under oxidative stress in vitro. PC12 cells conditioned medium and PC12 cell's exosomes significantly accelerated the apoptosis of BMSCs induced by H2O2. Moreover, the cleaved caspase-3, cytochrome (Cyt) C, lactate dehydrogenase (LDH) releases, and apoptotic percentage were increased, and the ratio of Bcl-2/Bax and cell viability were decreased. Inhibition of exosome secretion via Rab27a small interfering RNA prevented BMSCs apoptosis in vitro. In addition, hypoxia-preconditioned promoted the survival of BMSCs under oxidative stress both in vivo after SCI and in vitro. Our results also indicate that HIF-1α plays a central role in the survival of BMSCs in hypoxia pretreatment under oxidative stress conditions. siRNA-HIF-1α increased apoptosis of BMSCs; in contrast, HIF-1α inducer FG-4592 attenuated apoptosis of BMSCs. Taken together, we found that the injured PC12 cells derived exosomes accelerate BMSCs apoptosis after SCI and in vitro, hypoxia pretreatment or activating expression of HIF-1α to be important in the survival of BMSCs after transplantation, which provides a foundation for application of BMSCs in therapeutic potential for SCI.

Vitexin alleviates ER-stress-activated apoptosis and the related inflammation in chondrocytes and inhibits the degeneration of cartilage in rats.

Excessive extracellular matrix degradation and chondrocyte apoptosis are the pathological features of osteoarthritis (OA). The ability of flavonoid compounds isolated from Chinese hawthorn leaves to exert protective effects on several diseases, via inhibition of oxidative stress and inflammation, has been demonstrated in several studies. This study explored the effects of vitexin on chondrocytes, and the underlying mechanisms thereof. Vitexin, an active ingredient in hawthorn leaf extracts, was shown to exert protective effects on chondrocytes, by inhibiting the expression of GRP78 and PDI, and an apoptotic protein (CHOP) induced by interleukin-1ß. It also modulated thapsigargin-induced upregulation of GRP78 and PDI and subsequently an apoptotic protein (CHOP). Among rat chondrocytes, both the ER stress-activated nuclear factor kappa B (NF-κB) pathway and the induced expression of inflammatory cytokines (IL-6 and TNF-α) were significantly inhibited by vitexin. Finally, vitexin attenuated the progression of OA in vivo in rats. Taken together, all data demonstrate the relationship of ER stress and inflammation in the progression of OA, the ability of vitexin to protect chondrocytes and thus its therapeutic potential in patients with OA.

An ultrastructural study of chondroptosis: programmed cell death in degenerative intervertebral discs in vivo.

Apoptosis has been regarded to mediate intervertebral disc degeneration (IDD); however, the basic question of how the apoptotic bodies are cleared in the avascular intervertebral disc without phagocytes, which are essential to apoptosis, remains to be elucidated. Our goals were to investigate the ultrastructure of nucleus pulposus (NP) cells undergoing chondroptosis, a variant of apoptotic cell death, in a rabbit annular needle-puncture model of IDD. Experimental IDD was induced by puncturing discs with a 16-G needle in New Zealand rabbits. At 4 and 12 weeks after puncture, progressive degeneration was demonstrated by X-ray, magnetic resonance imaging and histological staining. TUNEL staining suggested a significant increase in the apoptosis index in the degenerated NP. However, the percentage of apoptotic cells with the classic ultrastructure morphology was much less than that with chondroptotic ultrastructure morphology under transmission electron microscopy (TEM). The chondroptotic cells from the early to late stage were visualized under TEM. In addition, the percentage of chondroptotic cells was significantly enhanced in the degenerated NP. Furthermore, 'paralyzed' cells were found in the herniated tissue. Western blotting revealed an increase in caspase3 expression in the degenerated NP. The expression of the Golgi protein (58K) was increased by the fourth week after puncture but decreased later. These findings indicate that chondroptosis is a major type of programmed cell death in the degenerated rabbit NP that may be related to the progressive development of IDD.

Pterostilbene inhibits inflammation and ROS production in chondrocytes by activating Nrf2 pathway.

Pterostilbene has been reported as a potential drug to inhibit oxidative stress and inflammation. However, the effect of pterostilbene on chondrocytes and osteoarthritis remains to be elucidated. We sought to investigate whether pterostilbene could protect chondrocytes from inflammation and ROS production through factor erythroid 2-related factor 2 (Nrf2) activation. The pterostilbene toxicity on chondrocytes collected from cartilages of Sprague-Dawley rats was assessed by CCK-8 test. Immunofluorescence and Western blotting explored the nuclear translocation of Nrf2. Nrf2 expression was silenced by siRNA to evaluate the involvement of Nrf2 in the effect of pterostilbene on chondrocytes. Finally, osteoarthritis model was established by the transection of anterior cruciate ligament and partial medial meniscectomy in rats, and then these rats received pterostilbene 30 mg/kg, daily, p.o. for 8 weeks. Histology and immunohistochemistry were used to assess histopathological change and Nrf2 expression in cartilage. Nuclear translocation of Nrf2 was stimulated by pterostilbene without cellular toxicity. Pterostilbene inhibited the level of COX-2, iNOS, PGE2, and NO, as well as the mitochondrial and total intracellular ROS production induced by IL-1ß in chondrocytes, partially reversed by the Nrf2 silencing. Pterostilbene prevented cartilage degeneration and promoted the nuclear translocation of Nrf2 in cartilage. These results suggest that pterostilbene could inhibit the IL-1ß-induced inflammation and ROS production in chondrocytes by stimulating the nuclear translocation of Nrf2.

Cortical bone trajectory screws for the middle-upper thorax: An anatomico-radiological study.

To quantify the reference data concerning the morphometrics of the middle-upper thorax to guide the placement of cortical bone trajectory (CBT) screws.Eighty patients were studied on computed tomography (CT) scans. The reference anatomical parameters were measured. Next, 20 cadaveric specimens were implanted with CBT screws based on CT measurements. These specimens were then judged directly from the cadaveric vertebrae and X-ray.The maximum length of the trajectory, the maximum diameter, and the cephaled angle exhibited a slight increase trend while the transverse and sagittal angles of the pedicle tended to decrease from T3 to T8. We recommend that the width of CBT screw for middle-upper thoracic spine is 5.0 mm, the length is 25 to 35 mm. The cadaveric anatomical study revealed that 5/240 screws penetrated in the medial or lateral areas, 5/240 screws penetrated in the superior or inferior pedicle wall, and 2/240 screws did not fit into the superior endplate of the pedicle.The CBT screws are safe for the middle-upper thorax. This study provides a theoretical basis for clinical surgery.

Effect of autophagy induced by dexamethasone on senescence in chondrocytes.

The aim of the current study was to explore the effects of dexamethasone (DXM) on autophagy and senescence in chondrocytes. Collagen II and aggrecan were examined in normal chondrocytes isolated from Sprague­Dawley rats. Following stimulation with DXM, LysoTracker Red staining, monodansylcadaverine (MDC) staining, green fluorescent protein­red fluorescent protein­light chain 3 (LC3) and western blotting were used to detect autophagy levels in the chondrocytes. Mechanistic target of rapamycin (mTOR) pathway­associated molecules were investigated by western blotting. Cell senescence was analyzed by senescence­associated (SA)­ß­galactosidase (ß­gal) staining. A dose­dependent increase in the number of autophagic vacuoles was observed in the DXM­treated chondrocytes, as demonstrated by LysoTracker Red and MDC staining. A dose­dependent increase in autophagosome formation was observed in the DXM­treated chondrocytes. Expression of LC3­II and beclin­1 was increased by DXM, in particular in the cells treated with DXM for 4 days. However, P62 expression was reduced as a result of treatment. SA­ß­gal staining indicated that DXM increased cell senescence. Notably, DXM­induced cell senescence was exacerbated by the autophagic inhibitor 3­MA. Autophagy induced by DXM protected chondrocytes from senescence, and it is suggested that the mTOR pathway may be involved in the activation of DXM­induced autophagy.

A mini-invasive technique for severe arthrofibrosis of the knee: A technical note.

PURPOSE: In this article, a mini-invasive technique is described, which consists of arthroscopic adhesiolysis and quadriceps pie-crusting lengthening basing on pre-operative sonographic examination. Sonographic diagnostic value of quadriceps tendon fibrosis is also evaluated. METHODS: Pre-operative sonographic examination was performed to make an accurate location diagnosis of quadriceps fibrosis. After arthroscopic adhesiolysis, percutaneous pie-crusting release was performed basing on preoperative sonographic examination. An 18-gauge needle was used to puncture the stiff fibrous band of the distal and lateral quadriceps tendon under maximum knee flexion. The contractural quadriceps tendon is gradually released after 60-100 needle punctures. RESULTS: This technique was performed in five post-traumatic stiff knees and three stiff knees after previous infection. The contractural rectus femoris tendon is average 22% thinner than contralateral parts according to sonographic measurement. Mean maximum flexion increased from 35° preoperatively to 80° after arthroscopic adhesiolysis and 120° after pie-crusting. CONCLUSIONS: This technique is a simple, effective and mini-invasive method, allowing an immediate, aggressive rehabilitation postoperatively. Pre-operative sonographic location of quadriceps tendon fibrosis could potentially improve the efficacy and accuracy of percutaneous pie-crusting procedures.

[Arthroscopic treatment of symptomatic anterior cruciate ligament cysts of the knee].

OBJECTIVE: To explore the clinical symptom and effect of arthroscopic treatment of symptomatic anterior cruciate ligament (ACL) cysts of the knee. METHODS: Clinical data from 12 symptomatic ACL cysts patients from January 2005 to December 2010 were retrospectively analyzed,including 8 males and 4 females,with an average age of (33.7±9.5) years old (ranged, 19 to 53 years old). The locations were the left knee in 5 cases and the right knee in 7 cases. The disease duration ranged from 3 to 48 months,with a mean of (15.8±13.2) months. All cysts were arthroscopically resected. Range of motion was measured preoperatively and postoperatively, and Lysholm scoring system was used to evaluate the knee function. RESULTS: All the incisions healed by first intention, and no complications occurred. Twelve patients were followed up for an average of (32.3±6.6) months(ranged, 24 to 48 months). The symptoms of arthralgia,swelling and interlocking of the affected knees disappeared. There was no recurrence during the follow-up. There were significant differences in the range of motion and Lysholm score between pre-operation and post-operation. CONCLUSION: Arthroscopic surgery, showing its advantages of minimal invasion and rapid recovery,is an effective measure in the treatment of ACL cysts.

An intraoperative device to restore femoral offset in total hip arthroplasty.

BACKGROUND: Leg length discrepancy (LLD) after total hip arthroplasty (THA) can lead to unsatisfactory outcome. Our objective was to design and evaluate a simple and reliable intraoperative device (Length-offset Lever) to minimize leg length discrepancy. METHODS: This device was used in 51 patients undergoing primary total hip replacements. The leg length discrepancy was measured pre- and postoperatively based on plain radiographs. RESULTS: Preoperative radiographic leg length discrepancy averaged 13.5 ± 6.2 mm. Leg length discrepancy showed significant improvement, with a postoperative average of 4.1 ± 2.3 mm (p < 0.0001). There were no complications associated with this device. CONCLUSIONS: The 'Length-offset Lever' is a useful intraoperative tool to restore anatomic femoral offset and height of femoral head.

Differentiation of menstrual blood-derived stem cells toward nucleus pulposus-like cells in a coculture system with nucleus pulposus cells.

STUDY DESIGN: Human stromal stem cells derived from menstrual blood (MenSCs) and nucleus pulposus (NP) cells were cocultured under normal or low oxygen (O2) condition. OBJECTIVE: To assess the differentiation capability of MenSCs toward nucleus pulposus cells under normal or low oxygen condition. SUMMARY OF BACKGROUND DATA: Given the proliferative capacity and pluripotentiality of mesenchymal stem cells, mesenchymal stem cells transplantation is thought to be a promising approach to managing intervertebral disc degeneration. METHODS: Using coculture plates with 0.4-µm pore size polyethylene terephthalate track-etched inserts, MenSCs and NP cells (1:1 ratio) were cocultured with cell-to-cell contact for 2 weeks in normal (20% O2) or low oxygen tension (2% O2), respectively. Extracellular matrix accumulation was quantified by dimethylmethylene blue assay, histological staining, and quantitative reverse-transcription polymerase chain reaction. Novel characteristic human NP markers cytokeratin-19 (KRT19), carbonic anhydrase XII (CA12), and forkhead box F1 (FoxF1) were also detected by quantitative reverse-transcription polymerase chain reaction. RESULTS: The result of quantitative reverse-transcription polymerase chain reaction showed that aggrecan and COL2A1 genes expression was significantly increased in differentiated MenSCs (P < 0.05). There was significantly more COL2A1 gene expression in normoxic group than that in low O2 group (P < 0.05). But no significant difference was observed in aggrecan gene expression between normoxic group and low O2 group. These aforementioned results were also confirmed by histological analysis. We also found that the characteristic NP markers (KRT19, CA12, FoxF1) were significantly upregulated in differentiated MenSCs. Moreover, low O2 tension (2%) further enhanced these genes expression (P < 0.05). CONCLUSION: In our study, MenSCs were successfully differentiated into NP-like cells and may become a new source of seed cells for the treatment of intervertebral disc degeneration in the future. LEVEL OF EVIDENCE: N/A.