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Chia-Hsien Chen,1–3 Wei-Chuan Chen,4 Chun-Yi Lin,5 Chih-Hwa Chen,1–3 Yang-Hwei Tsuang,1,2 Yi-Jie Kuo2,6 1Department of Orthopedics, Shuang Ho Hospital, Taipei Medical University, New Taipei, Taiwan; 2Department of Orthopedic Surgery, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; 3School of Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei, Taiwan; 4Graduate School of Biotechnology and Bioengineering, Yuan Ze University, Taoyuan City, Taiwan; 5Department of Orthopedic Surgery, Taipei Medical University Hospital, Taipei, Taiwan; 6Department of Orthopedic Surgery, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan Background: Estrogen deficiency is associated with musculoskeletal disorders. Sintered dicalcium pyrophosphate (SDCP) is a novel antiosteoporotic agent. In this study, we examined its use for restoration of bone quality and attenuation of disc degeneration in ovariectomy rats.Methods: Sixty female Sprague Dawley rats were randomly divided into 3 groups, namely sham group undergoing sham surgery, ovariectomy (OVX) group receiving an equivalent volume of isotonic sodium chloride solution, and OVX/SDCP group orally administered with 0.25 mg/mL SDCP. Animals were sacrificed at 3 and 6 months post ovariectomy and lumbar vertebrae and intervertebral discs were harvested. Bone mineral density, micro-computed tomography analysis, and biomechanical testing were performed to assess bone quality. Histological analysis with hematoxylin and eosin, Alcian blue, and Masson’s trichrome stain were conducted to determine disc degeneration. Immunohistochemistry and real-time PCR were carried out to measure the expressions of aggrecan, type I collagen, type II collagen, and MMP-1, MMP-3, and MMP-13.Results: SDCP improved bone quality as observed by the results of increased bone mineral density and stiffness in OVX rats. The improvement in disc degeneration induced by estrogen withdrawal was associated with reduced gene expressions of MMPs and increased production of collagen type II.Conclusion: SDCP prevents osteoporosis and ameliorates disc degeneration in OVX rats. It represents a favorable therapeutic agent for osteoporotic and osteoarthritic conditions in clinical practice. Keywords: sintered dicalcium pyrophosphate, ovariectomy, disc degeneration, matrix metalloprotease, inflammation

Vitamin D-binding protein (DBP) has an anabolic effect on the skeleton and reportedly enhances bone ingrowth. We used an in vivo critical bone defect model to determine whether local administration of DBP promotes bone defect healing. We created a 5-mm segmental bone defect in the radial shaft in a rat model. Forty-eight rats were assigned to eight groups: local application of 1 microg, 5 microg, 10 microg, or 50 microg DBP (DBP-1, DBP-5, DBP-10, DBP-50), autogenous bone marrow mononuclear cells with or without 10 microg DBP (BM-DBP-10, BM), 80 microg BMP-2 delivered in gelatin sponge (BMP-2), and the sham operated group. Radiographic evaluation, histological stains, and epifluorescence microscopy were performed. Grossly, all bone gaps of the BMP-2 group were solidly bridged by callus, while all those in the sham operated group remained unhealed by 9 weeks. Only one specimen of the BM-DBP-10 and DBP-50 groups and three specimens of the BM group were solidly healed; pseudarthroses occurred in all of the other specimens. Histological study and radiographs of the specimens showed similar results. We did not observe the enhanced bone healing reported in a previous study. [ABSTRACT FROM AUTHOR]

Background: Ankle syndesmosis injury is a common condition, and the injury mechanism can be sorted into pure syndesmosis injury, Weber-B, and Weber-C type fractures. This study aims to evaluate the treatment outcomes and stability of suture-button fixation for syndesmosis injury with different injury mechanisms. We hypothesized that injury mechanisms would alter the stability of suture-button fixation., Methods: We retrospectively reviewed 63 patients with ankle syndesmosis injury who underwent surgery with TightRope (Arthrex, Naples, FL, USA) from April 2014 to February 2019. The stability of suture-button fixation with TightRope was evaluated by comparing the preoperative, postoperative, and final follow-up measurements of tibiofibular clear space (TFCS), tibiofibular overlap (TFO), and medial clear space (MCS). A subgroup analysis for each demographic group and injury type including pure syndesmosis injury, Weber-B, and Weber-C type fractures were performed., Results: Syndesmosis was effectively reduced using TightRope. After the index surgery, the tibiofibular clear space was reduced from 7.73 to 4.04 mm, the tibiofibular overlap was increased from 3.05 to 6.44 mm, and the medial clear space was reduced from 8.12 to 3.54 mm. However, syndesmosis widening was noted at the final follow-up, especially in Weber-C type fractures (TFCS 3.82 to 4.45 mm, p < 0.01 and TFO 6.86 to 6.29 mm, p = 0.04). Though widened, the final follow-up values of tibiofibular clear space and tibiofibular overlap were in the acceptable range. Postoperatively and at the final follow-up, medial clear space was found to be significantly larger in the Weber-C group than in the pure syndesmosis and Weber-B groups (p < 0.05)., Conclusions: Suture-button fixation can offer anatomic reduction and dynamic fixation in syndesmosis injuries. However, when using this modality for Weber-C type fractures, more attention should be focused on the accuracy of reduction, especially of medial clear space, and rediastasis should be carefully monitored., Trial Registration: This trial was retrospectively approved by TMU-JIRB. Registration number N202004122, and the date of approval was May 06, 2020., Level of Evidence: III.

Background: The TomoFix plate has been extensively used in high tibial osteotomy surgery to stabilize the distracted tibial bones. However, distal pain related to plate irritation was considered one of the most relevant complications for this fixation device. This study aimed to correlate reports of distal pain with the profiles of the distracted tibia and initial plate and plate contour., Methods: This study used the finite-element method to investigate the profile-, distraction-, and contour-induced effects on stress distribution of the distal tibia-plate contact. The associations of two tibia profiles (normal and concave), distraction angles, and two plate profiles (contoured and non-contoured) were discussed in this study. The areas and stresses of the distal tibia-plate contact were chosen as comparison indices., Findings: Before weight-bearing, the non-contoured plates of the normal and concave tibia profiles consistently showed less contact area at the distal tibia-plate region. Consequently, the physiological loads make the non-contoured plate subject to more concentrated bone stresses and thus may induce more pain at the distal tibia-plate region than a contoured plate. When the distraction angle decreases, the tibia-plate gap increases. Prior to fixation, the tibia-plate gap can be evaluated by the profiles of the distracted tibia and non-contoured plate by use of anteroposterior radiograph and computer-aided simulation., Interpretation: In the situations of a lower distraction angle or a large tibia-plate gap, the use of a plate bender or a lag screw is recommended in order to contour the plate for reducing the concentrated stress at the distal tibia-plate region., Competing Interests: Declaration of Competing Interest Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: Adenine is a purine with a role in cellular respiration and protein synthesis. It is considered for its pharmacological potential. We investigated whether anti-inflammatory effect of adenine benefits on the proliferation and maturation of osteoblastic cells., Methods: Human osteoblast-like cells (MG-63) were cultured with adenine under control conditions or pre-treated with 10ng/mL of tumor necrosis factor-α (TNF-α) followed by adenine treatment. Cell viability was examined using dimethylthiazol diphenyltetrazolium bromide (MTT) assay. Expression of cytokines and osteogenic markers were analyzed using quantitative PCR (qPCR) and ELISA. Enzyme activity of alkaline phosphatase (ALP) and collagen content were measured., Results: TNF-α exposure led to a decreased viability of osteoblastic cells. Treatment with adenine suppressed TNF-α-induced elevation in IL-6 expression and nitrite oxide production in MG-63 cells. Adenine induced the osteoblast differentiation with increased transcript levels of collage and increased ALP enzyme activity., Conclusions: Adenine exerts anti-inflammatory activity in an inflammatory cell model. Adenine benefits osteoblast differentiation in normal and inflammatory experimental settings. Adenine has a potential for the use to treat inflammatory bone condition such as osteoporosis.

Background: Platelet-rich fibrin (PRF) is a bioactive biomaterial wherein cytokines are enmeshed within the interconnecting fibrin network. PRF can be fabricated into a patch to augment healing of the interface between a tendon graft and bone tunnel., Hypothesis: The bioactivity of a PRF scaffold is preserved after PRF is mechanically compressed into a patch. A bioactive PRF patch could promote the incorporation of a tendon graft within the bone tunnel through the formation of a tendon-bone healing zone composed of both fibrocartilaginous tissue and new bone., Study Design: Controlled laboratory study., Methods: Bioactivity of PRF was evaluated through treatment of rabbit tenocytes with PRF-conditioned medium and cultivation of cells on a PRF patch. Cellular morphologic features, viability, and differentiation were analyzed accordingly. In an animal study, a rabbit tendon-bone healing model was established through use of New Zealand White rabbits. The implanted tendon graft was enveloped circumferentially with a bioactive PRF patch before being pulled through a bone tunnel in the proximal tibia. Micro-computed tomography (micro-CT) imaging and histological and biomechanical analyses of the tendon-bone interface were performed at 12 weeks postoperatively., Results: PRF improved the viability of the cultured tenocytes. The effects of PRF on in vitro mineralization of tenocytes were comparable with the effects of standard culture medium. The gene expressions of type I collagen and osteopontin were upregulated upon PRF treatment. For the in vivo study, micro-CT images revealed significant new bone synthesis at the tendon-bone interface in the PRF-enveloped group. The tendon-bone healing zone was characterized by abundant fibrocartilage tissue and new bone formation as demonstrated by histological analysis. Biomechanical testing showed significantly higher ultimate loads in the PRF-enveloped group., Conclusion: Bioactive PRF could effectively augment healing of tendon graft to bone by inducing the formation of a transitional tendon-bone healing zone composed of fibrocartilage and bone., Clinical Relevance: Complete healing of the tendon graft in the bone tunnel is a prerequisite for successful ligament reconstruction, which would allow early and aggressive rehabilitation and rapid return to preinjury activity level. From a translational standpoint, the PRF-augmented healing in this rabbit animal model showed a promising biological approach to enhance tendon graft to bone healing via promotion of the functional anchorage between the 2 different materials.

Healing of an anterior cruciate ligament graft in bone tunnel yields weaker fibrous scar tissue, which may prolong an already prolonged healing process within the tendon-bone interface. In this study, gelatin molecules were added to thermosensitive chitosan/β-glycerol phosphate disodium salt hydrogels to form chitosan/gelatin/β-glycerol phosphate (C/G/GP) hydrogels, which were applied to 0.1 mg/mL collagenase carrier in the tendon-bone junction. New Zealand white rabbit's long digital extensor tendon was detached and translated into a 2.5-mm diameter tibial plateau tunnel. Thirty-six rabbits underwent bilateral surgery and hydrogel injection treatment with and without collagenase. Histological analyses revealed early healing and more bone formation at the tendon-bone interface after collagenase partial digestion. The area of metachromasia significantly increased in both 4-week and 8-week groups after collagenase treatment ( p < 0.01). Micro computed tomography showed a significant increase in total bone volume and bone volume/tissue volume in the 8 weeks after collagenase treatment, compared with the control group. Load-to-failure was significantly higher in the treated group at 8 weeks (23.8 ± 8.13 N vs 14.3 ± 3.9 N; p = 0.008). Treatment with collagenase digestion resulted in a 66% increase in pull-out strength. In conclusion, injection of C/G/GP hydrogel with collagenase improves tendon-to-bone healing in a rabbit model., Competing Interests: The authors declare no conflict of interest.

Schisandra chinensis (Turcz.) Baill. ( S. chinensis ) is a well-known botanical medicine and nutritional supplement that has been shown to have potential effects on neurodegeneration. To investigate the potential neuroprotective effect of S. chinensis fruit extract, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was used to induce behavioral disorders and dopaminergic neuronal damage in mice, and biochemical indicators were examined. Male C57BL/6 mice were used to establish the MPTP-induced parkinsonian syndrome model. Open field and rotarod tests were performed to evaluate the overall manifestation of motor deficits and rodent motor coordination. The mice were divided into 8 groups as follows: normal control; MPTP alone (25 mg/kg, i.p.); S. chinensis extract pretreatment (0.5, 1.5, 5 g/kg, p.o.); and S. chinensis extract treatment (0.5, 1.5, 5 g/kg, p.o.). Liquid chromatography coupled to electrochemical detection was used to monitor neurochemicals in the striatum. Tyrosine hydroxylase content was measured by immunohistochemistry, and biochemical antioxidative indicators were used to evaluate the potential neuroprotective effects of S. chinensis fruit extract. The results demonstrated that treatment with S. chinensis fruit extract ameliorated MPTP-induced deficits in behavior, exercise balance, dopamine level, dopaminergic neurons, and tyrosine hydroxylase-positive cells in the striatum of mice. Among the pretreated and treatment groups, a high dose of S. chinensis fruit extract was the most effective treatment. In conclusion, S. chinensis fruit extract is a potential herbal drug candidate for the amelioration and prevention of Parkinson's disease.

Background: Various surgical techniques are available to reduce chronic instability of the lateral ankle ligament complex. The most effective method for these procedures remains controversial. This report presents a surgical technique that is similar to the Broström procedure and uses a modified, nonaugmented repair technique., Materials and Methods: 38 soldiers with a history of chronic lateral ankle instability and poor ankle function underwent plication of the anterior talofibular ligament-lateral capsule complex with transosseous fixation of the calcaneofibular ligament through a fibular bone tunnel between 2004 and 2007. This study included 33 men and 5 women with a mean age of 25.6 years (range 18-36 years) at the time of surgery. Each patient was confirmed to have a history of chronic lateral ankle instability after an inversion injury, and symptoms had been noted for at least 1 year. The patients were followed up with stress radiographs, American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot functional score, and the Sefton assessment system. The mean followup period was 77.6 months (range 66-89 months)., Results: At the last evaluation, the talar tilt reduced from an average of 13.9° ± 2.4° before surgery to 3.8° ± 1.8° after surgery, and anterior drawer displacement reduced from 9.6 ± 2.9 mm to 2.3 ± 1.6 mm. The mean AOFAS ankle-hindfoot scale score for functional stability increased from 71.6 ± 4.0 points preoperatively to 95.6 ± 4.0 points postoperatively. As evaluated by the Sefton assessment system, 36 patients (95%) reported an excellent or good functional outcome. All patients resumed normal daily activities and active military duty after the surgery., Conclusion: The procedure described here could be considered a viable alternative option to anatomic reconstruction such as the modified Broström procedure and might be appropriate for the general population., Competing Interests: There are no conflicts of interest.

Background and Objectives: This study is a meta-analysis of randomized controlled trials comparing the efficacy of transcutaneous electrical nerve stimulation (TENS) to a control and to other nerve stimulation therapies (NSTs) for the treatment of chronic back pain., Methods: Citations were identified in MEDLINE, the Cochrane Library, Google Scholar, and ClinicalTrials.gov through June 2014 using the following keywords: nerve stimulation therapy, transcutaneous electrical nerve stimulation, back pain, chronic pain. Control treatments included sham, placebo, or medication only. Other NSTs included electroacupuncture, percutaneous electrical nerve stimulation, and percutaneous neuromodulation therapy., Results: Twelve randomized controlled trials including 700 patients were included in the analysis. The efficacy of TENS was similar to that of control treatment for providing pain relief (standardized difference in means [SDM] = -0.20; 95% confidence interval [CI], -0.58 to 0.18; P = 0.293). Other types of NSTs were more effective than TENS in providing pain relief (SDM = 0.86; 95% CI, 0.15-1.57; P = 0.017). Transcutaneous electrical nerve stimulation was more effective than control treatment in improving functional disability only in patients with follow-up of less than 6 weeks (SDM = -1.24; 95% CI, -1.83 to -0.65; P < 0.001). There was no difference in functional disability outcomes between TENS and other NSTs., Conclusions: These results suggest that TENS does not improve symptoms of lower back pain, but may offer short-term improvement of functional disability.

Background: Insufficient cell numbers still present a challenge for articular cartilage repair. Converting heterotopic auricular chondrocytes by extracellular matrix may be the solution., Hypothesis: Specific extracellular matrix may convert the phenotype of auricular chondrocytes toward articular cartilage for repair., Study Design: Controlled laboratory study., Methods: For in vitro study, rabbit auricular chondrocytes were cultured in monolayer for several passages until reaching status of dedifferentiation. Later, they were transferred to chondrogenic type II collagen (Col II)-coated plates for further cell conversion. Articular chondrogenic profiles, such as glycosaminoglycan deposition, articular chondrogenic gene, and protein expression, were evaluated after 14-day cultivation. Furthermore, 3-dimensional constructs were fabricated using Col II hydrogel-associated auricular chondrocytes, and their histological and biomechanical properties were analyzed. For in vivo study, focal osteochondral defects were created in the rabbit knee joints, and auricular Col II constructs were implanted for repair., Results: The auricular chondrocytes converted by a 2-step protocol expressed specific profiles of chondrogenic molecules associated with articular chondrocytes. The histological and biomechanical features of converted auricular chondrocytes became similar to those of articular chondrocytes when cultivated with Col II 3-dimensional scaffolds. In an in vivo animal model of osteochondral defects, the treated group (auricular Col II) showed better cartilage repair than did the control groups (sham, auricular cells, and Col II). Histological analyses revealed that cartilage repair was achieved in the treated groups with abundant type II collagen and glycosaminoglycans syntheses rather than elastin expression., Conclusion: The study confirmed the feasibility of applying heterotopic chondrocytes for cartilage repair via extracellular matrix-induced cell conversion., Clinical Relevance: This study proposes a feasible methodology to convert heterotopic auricular chondrocytes for articular cartilage repair, which may serve as potential alternative sources for cartilage repair.

Recent advances in tissue engineering have led to potential new strategies, especially decellularization protocols from natural tissues, for the repair, replacement, and regeneration of intervertebral discs. This study aimed to validate our previously reported method for the decellularization of annulus fibrosus (AF) tissue and to quantify potentially antigenic α-Gal epitopes in the decellularized tissue. Porcine AF tissue was decellularized using different freeze-thaw temperatures, chemical detergents, and incubation times in order to determine the optimal method for cell removal. The integrity of the decellularized material was determined using biochemical and mechanical tests. The α-Gal epitope was quantified before and after decellularization. Decellularization with freeze-thaw in liquid nitrogen, an ionic detergent (0.1% SDS), and a 24 h incubation period yielded the greatest retention of GAG and collagen relative to DNA reduction when tested as single variables. Combined, these optimal decellularization conditions preserved more GAG while removing the same amount of DNA as the conditions used in our previous study. Components and biomechanical properties of the AF matrix were retained. The decellularized AF scaffold exhibited suitable immune-compatibility, as evidenced by successful in vivo remodeling and a decrease in the α-Gal epitope. Our study defined the optimal conditions for decellularization of porcine AF tissues while preserving the biological composition and mechanical properties of the scaffold. Under these conditions, immunocompatibility was evidenced by successful in vivo remodeling and reduction of the α-Gal epitope in the decellularized material. Decellularized AF scaffolds are potential candidates for clinical applications in spinal surgery.

Although platelet-rich fibrin (PRF) has been used in clinical practice for some time, to date, few studies reveal its role as a bioactive scaffold in facilitating meniscal repair. Here, the positive anabolic effects of PRF on meniscocytes harvested from the primary culture of a rabbit meniscus were revealed. The rabbit meniscocytes were cultured with different concentrations of PRF-conditioned medium, and were evaluated for their ability to stimulate cell migration, proliferation, and extracellular matrix formation. In vivo , meniscal defects were created via an established rabbit animal model and were evaluated by a histology-based four-stage scoring system to validate the treatment outcome three months postoperatively. The in vitro results showed that PRF could induce cellular migration and promote proliferation and meniscocyte extracellular matrix (ECM) synthesis of cultured meniscocytes. In addition, PRF increased the formation and deposition of cartilaginous matrix produced by cultured meniscocytes. Morphological and histological evaluations demonstrated that PRF could facilitate rabbit meniscal repair. The data highlight the potential utility of using PRF in augmenting the healing of meniscal injuries. These advantages would benefit clinical translation, and are a potential new treatment strategy for meniscal repair., Competing Interests: The authors declare no conflict of interest.

The dynamic hip screw (DHS) is commonly used in the treatment of femoral intertrochanteric fracture with high satisfactory results. However, post-operative failure does occur and result in poor prognosis. The most common failure is femoral head varus collapse, followed by lag screw cut-out through the femoral head. In this study, a novel-designed DHS with two supplemental horizontal blades was used to improve the fixation stability. In this study, nine convention DHS and 9 Orthopaedic Device Research Center (ODRC) DHSs were tested in this study. Each implant was fixed into cellular polyurethane rigid foam as a surrogate of osteoporotic femoral head. Under biaxial rocking motion, all constructs were loaded to failure point (12mm axial displacement) or up to 20,000 cycles of 1.45kN peak magnitude were achieved, whichever occurred first. The migration kinematics was continuously monitored and recorded. The final tip-to-apex distance, rotational angle and varus deformation were also recorded. The results showed that the ODRC DHS sustained significantly more loading cycles and exhibited less axial migration in comparison to the conventional DHS. The ODRC DHS showed a significantly smaller bending strain and larger torsional strain compared to the conventional DHS. The changes in tip-to-apex distance (TAD), post-study varus angle, post-study rotational angle of the ODRC DHS were all significantly less than that of the conventional DHS (p < 0.05). We concluded that the ODRC DHS augmented with two horizontal wings would increase the bone-implant interface contact surface, dissipate the load to the screw itself, which improves the migration resistance and increases the anti-rotational implant effect. In conclusion, the proposed ODRC DHS demonstrated significantly better migration resistance and anti-rotational effect in comparison to the conventional DHS construct., (Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.)

Objective: To present a rare case of serous degeneration of bone marrow which resembles primary spinal tumor or bony metastasis to spine. Serous degeneration of bone marrow or gelatinous marrow transformation is a rare disease characterized by focal marrow hypoplasia, fat atrophy, and accumulation of extracellular mucopolysaccharides abundant in hyaluronic acid. Few literature was reviewed and few clinical case was presented., Methods: Two cases of serous marrow transformation were reported., Results: In the first case, a 29-year-old man suffered from severe left buttock pain. Bone metastasis was impressed in radiology examinations. Percutaneous endoscopic lumbar discectomy was performed along with bone biopsy. In the second case, a 49-year-old man presented lower back pain with radiation to bilateral lower legs. Magnetic resonance imaging revealed a water-like signal lesion in sacrum. Serous marrow transformation was confirmed pathologically in both cases., Conclusion: To the best of our knowledge, a case of serous degeneration of bone marrow resembling malignancy has not been reported in the literature. In this report, two cases demonstrate serous transformation of bone marrow mimics spinal tumor.

Several plate systems for high tibial osteotomy (HTO) have been developed to stabilize the opening wedge of an osteotomized tibia. Among them, the TomoFix system, having a quasi-straight and T-shaped design, has been widely adopted in the literature. However, this system is implemented by inserting a lag (i.e., cortical) screw through the proximal combi-hole, to deform the plate and pull the distal tibia toward the plate. This process potentially induces plate springback and creates an elastic preload on the osteotomized tibia, especially at the lateral hinge of the distracted wedge. Using the finite-element method, this study aims to investigate the contoured effect of lag-screw application on the biomechanical behavior of the tibia-plate construct. Two tibial profiles (normal and more concave), three distraction angles (6°, 9°, and 12°), and three knee loads (intraoperative: contouring plate; postoperative: weight and nonweight bearing) are systematically varied in this study. The wedge instability and fracture risk at the lateral hinge are chosen as the comparison indices. The results show the necessity of preoperative planning for a precontoured procedure, rather than elastic deformation using a lag screw. Within the intraoperative period, a more concave tibial profile and/or reduced distraction angle (i.e., 6° or 9°) necessitate a higher compressive load to elastically deform the plate, thereby deteriorating the lateral-hinge fracture risk. A precontoured plate is recommended in the case that the proximal tibia is highly concave and the distraction angle is insufficient to stretch the tibial profile., (Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.)

Aims: Intervertebral disc (IVD) degeneration was believed to contribute to lower back pain. The aim of the study was to investigate the pathogenesis and regulatory mechanism of puncture-induced IVD degeneration., Main Methods: We established a rat-tail puncture model using Kirschner wire and a homemade stopper. The progress of disc degeneration was evaluated by histological examination and the quantitative measurement of type I, type II collagen and other factors expression at 0.5, 1, 2, 6, and 12weeks after puncture and was compared with control rats of the same age., Key Findings: Histological examination and Safranin-O staining revealed progressive degeneration of the punctured disc. Matrix metalloproteinase 13 (MMP13) was increased at 1week after puncture but did not change in the control group. The interleukin-1 beta (IL-1β) mRNA expression level was elevated at the acute stage after puncture compared with the control group. The hypoxia inducible factor 2 (HIF-2) increased expression in punctured groups. Additionally, compare to adjacent non-punctured segments, HIF-2α expression level transiently increased and then decreased in the nucleus pulposus immediately following puncture, and it then increased 12weeks after puncture., Significance: The degenerative changes observed in this rat-tail puncture model are similar to human disc degeneration and that this model may be valuable for elucidating the molecular mechanisms and pathways underlying disc degeneration., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Over the last few years, new treatments for a damaged intervertebral disc (IVD) have included strategies to repair, replace, or regenerate the degenerative disc. However, these techniques are likely to have limited success, due to insufficiently effective means to address the damaged anulus fibrosus (AF). Here, we try to develop a bioprocess method for decellularization of the xenogeneic AF tissue, with a view to developing a scaffold as a potential candidate for clinical application in spinal surgery., Methods: Porcine AFs were decellularized using freeze-thaw cycles, followed by various combined treatments with 0.1% sodium dodecyl sulfate (SDS) and nucleases., Results: Hematoxylin and eosin (H & E) staining showed that decellularization was achieved through the decellularization protocols. Biochemical analyses revealed 86% reduction in DNA, but only 15.9% reduction in glycosaminoglycan (GAG) content, with no significant difference in the hydroxyproline content. There was no appreciable cytotoxicity of the acellular AF. Biomechanical testing of the acellular AF found no significant decline in stiffness or Young's modulus., Conclusions: Porcine AF tissues were effectively decellularized with the preservation of biologic composition and mechanical properties. These results demonstrate that acellular AF scaffolds would be a potential candidate for clinical application in spinal surgery.

Background: The treatment of adhesive capsulitis is a dilemma for orthopaedic rehabilitation specialists. In this study, we assessed whether extracorporeal shockwave therapy (ESWT) improves the functional outcome of primary shoulder adhesive capsulitis., Methods: In this prospective, randomized, controlled, single-blind clinical trial, we enrolled 40 patients with primary adhesive capsulitis to assess whether ESWT can improve the functional outcome of primary adhesive capsulitis better than oral steroid therapy. Patients were allocated to the oral steroid group or ESWT group with randomization. Functional outcome evaluations were performed using the Constant Shoulder Score (CSS) and Oxford Shoulder Score., Results: Both groups showed significant improvement in the Oxford Shoulder Score evaluation throughout the study period. In the ESWT group, the total CSS and range of motion (ROM) parameter of the CSS in the ESWT group showed significant improvement from the fourth week that was better than that in the steroid group; the activities–of–daily living (ADL) parameter of the CSS achieved significance and was better than that in the steroid group at the sixth week. For the steroid group, pain was significantly reduced from baseline to the fourth week of the study; ADL and ROM improved at the fourth to 12th week. For the ESWT group, ADL and ROM improvements were significant from baseline to the sixth week., Conclusion: Our results showed that ESWT can be an alternative treatment, at least in the short-term, for primary adhesive capsulitis of the shoulder. In addition, all of the side effects of ESWT were transient and tolerable.

The aim of this study was to evaluate the effect of sintered dicalcium pyrophosphate (SDCP) on fracture healing in an osteoporotic rat model. Female Sprague-Dawley rats (8 weeks old) were randomly allocated into five groups: sham-operated group, and bilateral ovariectomized group treated with SDCP, alendronate, calcitonin, or no treatment. Rats were sacrificed at 6 or 16 weeks after fracture. Fracture sites were examined by microcomputed tomography (microCT), histology, and mechanical testing. The results showed that SDCP mildly suppressed callus remodeling at 6 weeks, but not at 16 weeks. The lamellar bone in the callus area and new cortical shell formation in SDCP-treated group were similar to that of the sham group at 16 weeks after fracture, indicating there was no delayed callus remodeling into lamellar bone. At both 6 and 16 weeks after fracture, ultimate stress and elastic modulus were similar between the SDCP and sham groups, and the mechanical strength in these groups was better than that in other groups. Finally, analysis of the serum bone markers CTX-1 and P1NP suggested that SDCP decreased the bone turnover rate and promoted proper fracture healing. The effect of SDCP is superior to that of alendronate and calcitonin in the healing of osteoporotic fractures., (© The Author(s) 2014.)

Background: Un-physiological loads play an important role in the degenerative process of inter-vertebral discs (IVD). In this study, we used an in vitro and in vivo rat model to investigate the mechanism of nucleus pulposus (NP) cells apoptosis induced by mechanical stress., Methods: Static compressive load to IVDs of rat tails was used as the in vivo model. For the in vitro model, NP cells were tested under the physiological and un-physiological loading. For histological examination, apoptotic index study, and apoptotic gene expression, we also selected cytokines [bone morphogenetic protein (BMP)-2/7, insulin-like growth factor (IGF)-1, platelet-derived growth factor (PDGF)] to be analyzed., Results: Under mechanical loading, cellular density was significantly decreased, but there was an increase of TUNEL positive cells and apoptosis index. In a dose-dependent manner; the necrosis became apparent in the un-physiologic strain. The selected cytokines (BMP-2/7, IGF-1, PDGF) can significantly reduce the percentage of apoptotic and necrotic cells., Conclusions: We conclude that the intrinsic (mitochondrial) apoptotic pathway plays an important role in the compressive load-induced apoptosis of NP cells. Combination therapy reducing the mechanical load and selected cytokines (BMP-2/7, IGF-1 and PDGF) may have considerable promise in the treatment of spine disc degeneration.

Di-isononyl phthalate (DINP) is a general-purpose plasticizer for polyvinyl chloride. However, this industrial chemical plasticizer used as a clouding agent has recently contaminated food and beverages that had been inspected by Taiwan Food and Drug Administration. This study develops a sensitive and specific method combining ultra-performance liquid chromatography with electrospray ionization tandem mass spectrometry (UPLC-MS/MS) to investigate the pharmacokinetics of DINP in freely moving rats. Multiple reaction monitoring (MRM) was used to monitor the transition of the protonated molecule m/z of 419 [M+H](+) to the product ion 149 for DINP. The analyte was analyzed by UPLC-MS/MS with C18 column (100×2.1mm, 1.7 μm) which was equilibrated and eluted with an isocratic mixture of acetonitrile-ammonium acetate water solution (90:10, v/v) at a flow rate of 0.3 mL/min. Linear calibration curves were obtained for DINP concentration ranges of 0.05-2.5 μg/mL in plasma and feces. The feces were homogenized mechanically using 50% acetonitrile as the medium. The pharmacokinetic curve demonstrates that the disposition of DINP in rat plasma was fitted well by the two-compartment model after DINP administration (10 mg/kg, i.v.). The elimination half-life of DINP was 364±146 min and 150±58 min for intravenous (10 mg/kg) and oral (100 mg/kg) administration, respectively. The pharmacokinetic data indicate that the oral bioavailability of DINP in freely moving rats was about 1.19%. The total DINP excretion up to 48 h was 13.64±3.99% in feces., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Purpose: Deeper insights into the mechanical behavior of lumbar disc prostheses are required. Prior studies on the biomechanical performance of artificial discs were mostly performed with finite element analyses, but this has never been analyzed with altering articulate curvature. This study aimed to ascertain the influence of the geometry of a ball-and-socket disc prosthesis for the lumbar spine., Materials and Methods: Three-dimensional finite element model of human L4-L5 was reconstructed. Convex, concave, and elliptic artificial disc models were also established with Computer-Aided-Design software. Simulations included: (1) three articulate types of polyethylene (PE) insert were implanted inferiorly and (2) concave and convex PE inserts were implanted on the superior or inferior sides in flexion/extension, lateral bending, and axial rotation in the lumbar spine. Shear stresses and von Mises stresses on PE insert were assessed for their loading distributions., Results: High shear stresses of all articulate types occurred in flexion, and convex PE insert performed the maximum stress of 23.81 MPa. Under all conditions, stresses on concave PE inserts were distributed more evenly and lower than those on the convex type. Elliptic geometry enabled confining the rotation of the motion unit. The shear force on the convex PE insert on the inferior side could induce transverse crack because the shear stress exceeded yielding shear stress., Conclusions: The concave PE insert on the inferior side not only decreased loading concentration but had relatively low stress. Such a design may be applicable for artificial discs.

Background: The adverse effects of annulotomy during lumbar discectomy have been increasingly recognized, and methods are developing to repair the annular defect. Biomechanically, the repair should retain the intra-nuclear pressure, which is doubtful using the current suture techniques. Therefore, a new suture technique was designed and tested to close a simpler type of annular incision., Methods: A new suture technique, the modified purse-string suture, was introduced into a re-validated nonlinear finite element human disk model after creating a standard transverse slit incision, as well as two other suture techniques: either two simple sutures, or a horizontal crossed suture, and compared their contact pressure on the cleft contact surface. Then, porcine lumbar endplate-disk-endplate complexes with transverse slit incisions were repaired using the three techniques. Quantitative discomanometry was then applied to compare their leakage pressure, as a parameter of disk integrity., Findings: In finite element model, the new technique created the greatest contact pressure along the suture range (the outer annulus), and generated a minimum contact pressure at the critical point, which was 68% and 55% higher than the other two suture techniques. In quantitative discomanometry, the new suture technique also had an average leakage pressure of 85% and 49% higher than the other two suture techniques., Interpretation: The modified purse-string suture can generate higher contact pressure than the other two techniques at finite element analysis and in realistic animal models, which aids in retaining intra-discal pressure, and should be encouraged in clinical practice., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Inflammation has been proposed to be an important causative factor in ligamentum flavum hypertrophy. However, the mechanisms of mechanical load on inflammation of ligamentum flavum remain unclear. In this study, we used an in vitro model of human ligamentum flavum fibroblasts subjected to centrifugal force to elucidate the effects of mechanical load on cultured human ligamentum flavum fibroblasts; we further studied its molecular and biochemical mechanisms. Human ligamentum flavum fibroblasts were obtained from six patients undergoing lumbar spine surgery. Monolayer cultures of human ligamentum flavum fibroblasts were subjected to different magnitudes of centrifugal forces. Cell viability, cell death, biochemical response, and molecular response to centrifugal forces were analyzed. It was found that centrifugal stress significantly suppressed cell viability without inducing cell death. Centrifugal force at 67.1 g/cm(2) for 60 min significantly increases the production of prostaglandin E2 and nitric oxide as well as gene expression of proinflammatory cytokines, including interleukin (IL)-1α, IL-1β and IL-6, showed that centrifugal force-dependent induction of cyclooxygense-2 and inducible NO synthase required JNK and p38 mitogen-activated protein kinase, but not ERK 1/2 activities. This study suggested that centrifugal force does induce inflammatory responses in human ligamentum flavum fibroblasts. The activation of both JNK and p38 mitogen-activated protein kinase mechanotransduction cascades is a crucial intracellular mechanism that mediates cyclooxygense-2/prostaglandin E2 and inducible NO synthase/nitric oxide production.

The effects of low intensity pulsed ultrasound to tenocytes and osteocytes are well understood and applied clinically. However, its effects on cultured Schwann cells are still not well elucidated. This study was designed to elucidate the effects of low intensity pulsed ultrasound on cultured Schwann cells and their possible molecular mechanism. Schwann cells were harvested from sciatic nerves of 3-day-old Sprague-Dawley rats. Low intensity pulsed ultrasound stimulator (frequency: 1 MHz, duration: 2 min, duty cycle: 20%, total treatment time: 3 min) was applied to three different culture conditions: regular culture medium containing 0, 5, or 10% fetal bovine serum. The viability, damage, and differentiation of Schwann cells were examined; gene expression was also analyzed. In the presence of 0.3 W/cm(2) pulsed ultrasound stimulation, increases in cell viability and decreases in cell apoptosis were observed in the serum deprivation group; in this culture condition, interleukin-1, tumor necrosis factor-alpha, and protein zero genes expression were downregulated and Desert Hedgehog transcripts gene expression was upregulated. We concluded that intervention with low intensity pulsed ultrasound could promote Schwann cell proliferation, prevent cell death, and keep adequate phenotype presentation for peripheral nerve recovery. The low intensity pulsed ultrasound stimulation to an injured nerve site could be applied as early as possible especially when the microenvironment is almost serum-free to obtain the most benefit., (© 2010, Copyright the Authors. Artificial Organs © 2010, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.)

Ultrasound is an effective noninvasive treatment for various tendinopathies. However, how tenocytes convert ultrasound stimulation into cascades of cellular and molecular events is not well understood. The purpose of this study is to elucidate the signaling pathways of tenocytes during ultrasound stimulation. Primary cultures of tenocytes were harvested from Achilles tendons of Sprague-Dawley rats. The viability and proliferation of tenocytes, their genes expression, and the signaling pathways after ultrasound treatment with or without specific inhibitors were evaluated and analyzed. The results showed that ultrasound treatment (100 mW/cm(2) for 20 min) significantly enhanced matrix metalloproteinase 13 (MMP-13), c-Fos, and c-Jun gene expression, increased JNK and p38, but not extracellular signal-regulated kinase-1/2 (ERK1/2), phosphorylation at 5 min, and sustained up to 60 min. JNK inhibitor and p38 inhibitor, but not ERK1/2 inhibitor, attenuated ultrasound-dependent induction of MMP-13 expression, indicating that the JNK and p38 pathways are required for ultrasound-induced MMP-13 expression in tenocytes. We also found that SB431542 (transforming growth factor-beta (TGF-β) receptor kinases inhibitor) suppressed ultrasound-induced MMP?13 and c-Fos gene expression, and p38 phosphorylation. This study revealed that ultrasound treatment stimulates tenocytes proliferation and regulates their matrix metabolism through the cross-talk between TGF-β and ultrasound-induced mitogen-activated protein kinases (MAPKs) signaling pathways.

Mesenchymal stem cells (MSCs) found in bone marrow (BM)-MSCs are an attractive source for the regeneration of damaged tissues. Alternative postnatal, perinatal, and fetal sources of MSCs are also under intensive investigation. MSCs from the Wharton's jelly matrix of umbilical cord (WJ)-MSCs have higher pancreatic and endothelial differentiation potentials than BM-MSCs, but the underlying mechanisms are poorly understood. We compared the gene expression profiles, enriched canonical pathways, and genetic networks of BM-MSCs and WJ-MSCs. WJ-MSCs express more angiogenesis- and growth-related genes including epidermal growth factor and FLT1, whereas BM-MSCs express more osteogenic genes such as RUNX2, DLX5, and NPR3. The gene expression pattern of BM-MSCs is more similar to osteoblasts than WJ-MSCs, suggesting a better osteogenic potential. In contrast, WJ-MSCs are more primitive because they share more common genes with embryonic stem cells. BM-MSCs are more sensitive to environmental stimulations because their molecular signatures altered more significantly in different culture conditions. WJ-MSCs express genes enriched in vascular endothelial growth factor and PI3K-NFκB canonical pathways, whereas BM-MSCs express genes involved in antigen presentation and chemokine/cytokine pathways. Drylab results could be verified by wetlab experiments, in which BM-MSCs were more efficient in osteogenic and adipogenic differentiation, whereas WJ-MSCs proliferated better. WJ-MSCs thus constitute a promising option for angiogenesis, whereas BM-MSCs in bone remodeling. Our results reveal systematically the underlying genes and regulatory networks of 2 MSCs from unique ontological and anatomical origins, as well as the resulted phenotypes, thereby providing a better basis for cell-based therapy and the following mechanistic studies on MSC biology.

Statins inhibit 3-hydroxy-3-methylglutaryl-coenzyme A reductase, which catalyzes the conversion of 3-hydroxy-3-methylglutaryl-coenzyme A to mevalonate, a rate-limiting step in cholesterol synthesis. Statins are able to reduce cardiovascular risk in hypercholesterolemic patients. In recent years, the possible effect of statins on bone tissue has received particular attention. The present study was undertaken to understand the events of osteoblast differentiation induced by statins. Our hypothesis is that simvastatin promotes osteoblast viability and differentiation via Ras/Smad/Erk/bone morphogenic protein (BMP)-2 signaling pathway. The viability and differentiation of osteoblasts were examined by mitochondrial activity assay, alkaline phosphatase (ALP) activity, and gene expression. The associated signaling pathways were analyzed by cytoplasmic and membrane proteins manifestation. After administration of 10(-6) M simvastatin, the ALP activity was significantly enhanced, and the expression of BMP-2, ALP, sialoprotein, and type I collagen genes were up-regulated. After simvastatin treatment, both the RasGRF1 and phospho-RasGRF1 in the cytoplasm decreased significantly, whereas those on the plasma membrane increased. A marked increase in membranous GAP-associated protein (P190) and the activated form of both phospho-extracellular signal-regulated kinase1/2 and phospho-Smad1 were also noted. In conclusion, this study shows that statins pose a positive effect on the metabolism of osteoblasts. Simvastatin can promote osteoblast viability and differentiation via membrane-bound Ras/Smad/Erk/BMP-2 pathway. Statins stimulate osteoblast differentiation in vitro and may be a promising drug for the treatment of osteoporosis in the future., (2010 Elsevier Inc. All rights reserved.)

To characterize the pathway of ceftriaxone penetration into intervertebral discs, rat-tail discs were collected and immersed in a ceftriaxone solution for an in vitro study. For this in vivo experiment, plasma and tail discs were collected 30 min after ceftriaxone administration (463.2 mg/kg, equal to 500 mg/kg disodium salt, iv). The ceftriaxone levels in the plasma and discs were determined with HPLC by a reversed-phase C18 column and a mobile phase of methanol and a 10 mM K(2)HPO(4) solution (pH 6.7) (21:79, v/v). The results indicate that ceftriaxone was undetectable by the in vitro model. The concentrations of ceftriaxone in plasma and in intervertebral discs were 147.4 ± 21.2 and 4.0 ± 1.7 µg/mL (as disodium salt), respectively. Our results suggest that a sufficient blood supply is required for the passive diffusion of ceftriaxone into intervertebral discs. The concentration ratio of ceftriaxone in intervertebral disc-to-plasma was about 2.7% at 30 min after ceftriaxone disodium administration (500 mg/kg, iv).

Background: Posterior lumbar interbody fusion (PLIF) cages have achieved satisfactory fusion results, but cases of cage migration or mechanical failure were repeatedly reported. Therefore, we conducted a finite element study to determine the impact of cage applications including number, positioning, and adding posterior instrumentation (PI)., Methods: A finite element model of the lumbar spine was generated from Computer Tomography scans and was validated. Partial laminectomy, diskectomy with partial facetectomy, and single or double-cage insertion were simulated onto the model, with or without posterior pedicle screws instrumentation. The maximal von Mises stresses between different loading conditions were compared between modalities to evaluate the risks of migration or mechanical failure., Results: Posterior instrumentation decreases at least half the distortion stress of cage-endplate interface and facet joints, and diminishes the differences between the stresses of inserting one or two cages. Based on one cage insertion, adding posterior instrumentation provides more efficient stability than an additional cage. Furthermore, an obliquely inserted cage with posterior instrumentation produced lower stress than a cage inserted on one side due to better structural symmetry. Conclusively, one oblique anterior cage and bilateral posterior pedicle screws reconstructed the tripod system as the intact disc and facet joints, and provided similar stability as two cages did.

Paget's disease in the Far East is quite rare. Age at diagnosis is usually greater than 50 years, and the disease typically affects the spine. Most patients are usually diagnosed with Paget's disease following radiographic examination for other purposes. It usually occurs at multiple vertebral levels, with only 10-25% of vertebral Paget's disease being monostotic. The disease rarely causes neurologic complications resulting from compression of intraspinal nerve tissue. Here, we present 2 cases of monostotic vertebral Paget's disease of the third lumbar vertebra. The first patient, who may be the first documented case of Paget's disease in the lumbar spine with progressive neurologic deficiency in an Asian population, received decompressive laminectomy due to marked spinal stenosis with neurologic deficits. The symptoms were greatly relieved following surgery, and ambulatory ability was restored. The second patient was diagnosed with Paget's disease following surgical biopsy. He remained asymptomatic at the most recent follow-up.

Study Design: Retrospective review of an anterior polyetheretherketone (PEEK) cage incorporated with a bovine xenograft to treat disorders of the cervical disc., Objective: To assess the achievement of fusion by PEEK cage with xenograft radiographically and clinically when used to perform ACDF., Summary of Background Data: Anterior cervical discectomy and fusion is the therapy of choice for degenerative disc disorders of the cervical spine. Although cage device increases initial stability of the levels treated, fusion is the key factor for satisfactory results. Filling the cage devices with autologous iliac bone grafts enable achievement of the best fusion result. Although the volume of harvested bone graft is minimal, donor-site morbidity is still a complication of concern. To avoid this adverse issue, we used a new bovine xenograft in place of autologous bone graft., Methods: Fifty-six patients (33 men and 23 women aged 31-78 years) underwent anterior cervical discectomy and fusion using PEEK cage with a bovine xenograft bone substitute to treat symptomatic cervical disorders. Radiographic and clinical results were assessed over 3 to 5 years of follow up., Results: Almost all patients had symptomatic improvement, and 84% reported good-to-excellent satisfaction. All cases achieved solid fusion, confirmed by radiographs and computed tomography, but cage subsidence occurred at 8 levels., Conclusion: As applied in anterior cervical fusion, the cage incorporated with the xenograft prevented donor-site morbidity and provided successful fusion.

Background: Chondrocytes can detect and respond to the mechanical environment by altering their metabolism. This study was designed to explore the effects of dynamic compression on chondrocyte metabolism., Methods: Chondrocytes were harvested from newborn Wistar rats. After 7 days of expansion, chondrocytes embedded in agarose discs underwent uniaxial unconfined dynamic compression loads at different amplitudes (5%, 10%, and 15%) and frequencies (0.5 Hz, 1.0 Hz, 2.0 Hz, and 3.0 Hz) with a duration of 24 hours. The delayed effects on the chondrocytes were studied at 1, 3, and 7 days after the experiment., Results: The results showed that at 10% strain, higher-frequency compression pressure can enhance the proliferation of chondrocytes. The synthesis of glycosaminoglycan (GAG) increased at 10%-15% strain and a 1-Hz load. The synthesis of nitric oxide (NO) increased at the 0.5-Hz load; while decreasing at the 15% strain. With 10% strain, 1 Hz dynamic compression, the proliferation of chondrocytes and GAG synthesis increased and persisted for 7 days, and NO synthesis decreased at the third and seventh days of culture., Conclusions: This study showed that chondrocytes respond metabolically to compressive loading, which is expected to modulate the growth and the resultant biomechanical properties of these tissue-engineered constructs during culture.

Somatic stem cell transplantation holds great promise in regenerative medicine. The best-characterized adult stem cells are mesenchymal stem cells (MSCs), neural stem cells (NSCs), and CD133(+) hematopoietic stem cells (HSCs). The applications of HSCs are hampered since these cells are difficult to maintain in an undifferentiated state in vitro. Understanding genes responsible for stem cell properties and their interactions will help on this issue. The construction of stem cell genetic networks will also help to develop rational strategies to revert somatic cells back to a stem-like state. We performed a systemic study on human CD133(+) HSCs, NSCs, MSCs, and embryonic stem cells and two different progenies of CD133(+) HSCs, microvascular endothelial cells (MVECs) and peripheral blood mononuclear cells. Genes abundant in each or in all three somatic stem cells were identified. We also observed complex genetic networks functioning in postnatal stem cells, in which several genes, such as PTPN11 and DHFR, acted as hubs to maintain the stability and connectivity of the whole genetic network. Eighty-seven HSC genes, including ANGPT1 and GATA2, were independently identified by comparing CD34(+)CD33(-)CD38(-) hematopoietic stem cells with CD34(+) precursors and various matured progenies. Introducing GATA2 into MVECs resulted in dedifferentiation-like transcriptome reprogramming, with HSC genes (such as ANGPT1) being up and endothelial genes (such as EPHB2) being down. This study provides a foundation for a more detailed understanding of human somatic stem cells. Expressing the newly discovered stem cell genes in matured cells might lead to a global reversion of somatic transcriptome to a stem-like status.

The shock wave is an effective noninvasive modality for resolving various tendon pathologies. However, scientific rationale and mechanism of shock wave therapy remains limited. This study aims to investigate the effects of shock waves and their biochemical mechanisms on tenocyte proliferation and collagen synthesis. Tenocytes harvested from Achilles tendons of Sprague-Dawley rats were used in this study. Cell viability was assayed by trypan blue exclusion methods. The colorimetric assay was determined to evaluate the mitochondria activity of the tenocytes after shock wave exposure. Synthesis of collagen, nitric oxide (NO) and transforming growth factor-beta1 (TGF-beta1) were determined and their gene expression was also studied. The results showed that there was a dose-dependent impairment of cell viability observed in 0.36 mJ/mm2 and 0.68 mJ/mm2 stimulation. In the proliferation assay, low energy level with low impulses (0.36 mJ/mm2 with 50 and 100 impulses) showed positive stimulatory effects, whereas the high energy level with high impulses (0.68 mJ/mm2 with 250 and 500 impulses) had significant inhibitory effects. At 0.36 mJ/mm2, 100 impulse shock waves treatment, up-regulation of proliferating cell nuclear antigen (PCNA) (at 6 and 24 h) and collagen type I, collagen type III and TGF-beta1 gene expression (at 24 h) were observed; these were followed by the increases in NO production (at 24 h), TGF-beta1 release (at 48 and 96 h) and collagen synthesis (at the 7th day). This study revealed that shock waves can stimulate tenocyte proliferation and collagen synthesis. The associated tenocyte proliferation is mediated by early up-regulation of PCNA and TGF-beta1 gene expression, endogenous NO release and synthesis and TGF-beta1 protein and then collagen synthesis.

Soy protein, a rich source of phytoestrogens, exhibit estrogen-type bioactivity. The purpose of this study was to determine if ingestion of isoflavones before ovariectomy can prevent bone loss following ovariectomy. Twenty-four nulliparous Wistar rats were randomly divided into four groups. In the normal diet groups, a sham operation was performed on Group A, while ovariectomy was performed on Group B. For Groups C and D, all rats were fed with an isoflavone-rich (25 mg/day) diet for one month, then bilateral ovariectomy were performed. In the rats in Group C, a normal diet was begun following the ovariectomy. The rats in Groups D continued to receive the isoflavone-rich diet for two additional months postoperatively. All rats were sacrificed 60 days after surgery. The weight of bone ash of the long bones and whole lumbar spine were determined. A histological study of cancellous bone was done and biochemical indices of skeletal metabolism were performed and analyzed. The markers of bone metabolism exhibited no significant changes. When compared with the sham-operated rats fed a normal diet, the bone mass of ovariectomized rats decreased significantly; pre-ovariectomy ingestion of an isoflavone-rich diet did not prevent bone loss. The bone mass of rats treated with an isoflavone-rich diet for three months was higher than controls two months after ovariectomy. Dietary isoflavones did not prevent the development of post-ovariectomy bone loss, but long-term ingestion of an isoflavone-rich diet increased the bone mineral contents after ovariectomy in young rats.

Several methods have been described to introduce DNA expression vectors into mammalian cells both in vitro and in vivo. Each system has benefits and limitations, and to date there is still no ideal method for gene transfer. In this study, we introduced a novel method of gene transfer by using Fe3O4 nanoparticles. The magnetic nanoparticles composed of Fe3O4, and the transfected genes used are Lac Z and enhanced green fluorescence protein gene (EGFG). Four different groups of preparations included in this study were homemade liposome-enveloped EGFP-DNA/Fe3O4, homemade liposome EGFP-DNA gene without magnetic Fe3O4 nanoparticles, lipofectamine 2000-enveloped EGFP-DNA, and EGFP-DNA gene only. Mice osteoblast and He99 lung cancer cell line were used as host cells for gene transfection. The time-dependent EGFP gene expression was monitored and analyzed. The results showed that the diameter of the complex was less than 100 nm. There was no cytotoxicity observed at any of the magnetic Fe3O4 nanoparticle concentrations tested. In the presence of magnetic field, the liposome-enveloped EGFP-DNA/Fe3O4 complex exhibited a much higher efficiency for transfecting EGFP-DNA into osteoblast cells under external magnetic fields. The gene can be transfected into cells with an aid of magnetic vectors and magnetic force. Under a gradient magnetic field, the efficiency of magnetofection is enhanced as compared to that without magnetic field.

Metal pins used to apply skeletal traction or external fixation devices protruding through skin are susceptible to the increased incidence of pin site infection. In this work, we tried to establish the photokilling effects of titanium dioxide (TiO2) nanoparticles on an orthopedic implant with an in vitro study. In these photocatalytic experiments, aqueous TiO2 was added to the tested microorganism. The time effect of TiO2 photoactivation was evaluated, and the loss of viability of five different bacteria suspensions (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus hirae, and Bacteroides fragilis) was examined by the viable count procedure. The bactericidal effect of TiO2 nanoparticle-coated metal plates was also tested. The ultraviolet (UV) dosage used in this experiment did not affect the viability of bacteria, and all bacteria survived well in the absence of TiO2 nanoparticles. The survival curve of microorganisms in the presence of TiO2 nanoparticles showed that nearly complete killing was achieved after 50 min of UV illumination. The formation of bacterial colonies above the TiO2 nanoparticle-coated metal plates also decreased significantly. In this study, we clearly demonstrated the bactericidal effects of titanium dioxide nanoparticles. In the presence of UV light, the titanium dioxide nanoparticles can be applicable to medical facilities where the potential for infection should be controlled.

Background: There has been no report related to comparison of fixation methods using minimally invasive dynamic hip screw (MIDHS), conventional dynamic hip screw (CDHS), and multiple cannulated screws (MCS) for treating the undisplaced femoral neck fractures., Methods: The study retrospectively evaluates the comparison of fixation methods. Ninety elderly patients (>60 years) with the undisplaced intracapsular femoral neck fractures were treated with osteosynthesis by either dynamic hip screw (DHS) or MCS. The patient distribution was regarded as randomized. A new minimally invasive technique of DHS (MIDHS) was presented. Pauwels' classification was used to evaluate the fracture verticality. Singh index was used to evaluate the bone quality. All patients were followed up retrospectively for at least 12 months to compare the clinical results among the MIDHS, CDHS, and MCS groups., Results: Pauwels types and Singh index were similar among the three groups (all p values >/=0.78). The CDHS group had significantly larger wound incision, greater hemoglobin level drop, and longer hospital stay than either the MIDHS or MCS groups (all p values /=0.28). The MIDHS group showed a trend of an increased rate of overall success compared with the MCS group, although this was not statistically significant (97% vs. 84.4%, p = 0.11)., Conclusion: CDHS had more disadvantages related to more soft tissue stripping than either MIDHS or MCS. MIDHS showed a trend of an increased rate of overall success in an elderly patient with undisplaced femoral neck fracture when compared with MCS.

Background and Purpose: Intensive eccentric exercise can cause muscle damage. We simulated an animal model of isokinetic eccentric exercise by repetitively stretching stimulated triceps surae muscle-tendon units to determine if such exercise affects the mechanical properties of the unit within its physiologic excursion., Methods: Biomechanical parameters of the muscle-tendon unit were monitored during isokinetic eccentric loading in 12 rabbits. In each animal, one limb (control group) was stretched until failure. The other limb (study group) was first subjected to isokinetic and eccentric cyclic loading at the rate of 10.0 cm/min to 112% (group I) or 120% (group II) of its initial length for 1 hour and then stretched to failure. Load-deformation curves and biomechanical parameters were compared between the study and control groups., Results: When the muscle-tendon unit received eccentric cyclic loading to 112%, changes in all biomechanical parameters - except for the slope of the load-deformation curve - were not significant. In contrast, most parameters, including the slope of the load-deformation curve, peak load, deformation at peak load, total energy absorption, and energy absorption before peak load, significantly decreased after isokinetic eccentric cyclic loading to 120%., Conclusion: We found a threshold for eccentrically induced injury of the rabbit triceps surae muscle at between 12% and 20% strain, which is within the physiologic excursion of the muscle-tendon units. Our study provided evidence that eccentric exercise may induce changes in the biomechanical properties of skeletal muscles, even within the physiologic range of the excursion of the muscle-tendon unit.

We report a young man with gouty discitis of the cervical spine. To our knowledge, our patient is the youngest patient with cervical gouty discitis reported in the literature. The clinical manifestation was similar to that of cervical spondylosis with radiculopathy. Gouty discitis was diagnosed only when tophi in the disc were found during surgery and proved by pathologic study. Surgical decompression followed by optimization of pharmacologic treatment enabled good recovery from neurologic complications.

In this study, we have evaluated the feasibility of developing a biodegradable collagenous small diameter vascular graft of 2mm diameter and 1cm length. In brief, bi-layer type I collagen membrane was fabricated under vacuum suction and lyophilization methods. The smooth muscle cells were inoculated into the lower side of the porous membrane, while endothelial cells were seeded onto upper smooth side of the membrane. After cultured for 7 days, the vascular substitute was either harvested for in vitro examination or in vivo implanted in the subcutaneous layer for biocompatibility test. The tubular vascular prosthesis was then used as a temporary absorbable guide that served as an in vivo vascular graft to promote the complete regeneration of rat inferior vena cava. After implantation for 12 weeks, a thin continuous layer of endothelial cells and smooth muscle cells were lined with the vascular lumen and tunic media, respectively. Histology results showed that there were no signs of significant thrombogeneity and intima hyperplasia. This tissue engineered vascular substitute not only had enough tensile strength and good biocompatibility, but also advanced vascular regeneration. In the future, we suggest that this biodegradable vascular substitute will provide with the possibility in application on small diameter prosthetic grafts in artificial blood vessels.

Tissue-engineered skin substitutes provided a feasibility to overcome the shortage of skin autograft by culturing keratinocytes and dermal fibroblasts in vitro. In this study, we applied bi-layer gelatin-chondrointin-6-sulfate-hyaluronic acid (gelatin-C6S-HA) biomatrices onto the severe combined immunodeficiency (SCID) mice to evaluate its effect on promoting wound healing. Human foreskin keratinocytes and dermal fibroblasts were cultured with reconstructed skin equivalent (rSE) for 7 days. The rSE was then grafted to the dorsum of SCID mice to evaluate its biocompatibility by histologic and immunohistochemistry analysis. The results showed that human epidermis were well-developed with the expression of differentiated markers and basement membrane-specific proteins at 4 weeks. After implantation, the percentages of skin graft take were satisfactory, while cell-seeded group was better than non-cell-seeded one. The basement membrane proteins including laminin, type IV collagen, type VII collagen, integrin alpha6, and integrin beta4 were all detected at the dermal-epidermal junction, which showed a continuous structure in the 4 weeks after grafting. This bi-layer gelatin-C6S-HA skin substitute not only has positive effect on promoting wound healing, but also has high rate of graft take. This rSE would have the potential to be applied on the extensively and deeply burned patients who suffer from severe skin defect in the near future.

Background: Caffeine consumption has been reported to decrease bone mineral density (BMD), increase the risk of hip fracture, and negatively influence calcium retention. In this study, we investigated the influence of caffeine on the osteoblasts behaviour., Method: Osteoblasts derived from newborn Wistar-rat calvaria was used in this study. The effects of various concentrations of caffeine on bone cell activities were evaluated by using MTT assay. Alkaline phosphatase (ALP) staining, von Kossa staining and biochemical parameters including ALP, lactate dehydrogenase (LDH), prostaglandin E2 (PGE2) and total protein were performed at day 1, 3, and 7. DNA degradation analysis under the caffeine influence was also performed., Results and Discussion: The results showed that the viability of the osteoblasts, the formation of ALP positive staining colonies and mineralization nodules formation in the osteoblasts cultures decreased significantly in the presence of 10 mM caffeine. The intracellular LDH, ALP and PGE2 content decreased significantly, the LDH and PGE2 secreted into the medium increased significantly. The activation of an irreversible commitment to cell death by caffeine was clearly demonstrated by DNA ladder staining., Conclusion: In summary, our results suggest that caffeine has potential deleterious effect on the osteoblasts viability, which may enhance the rate of osteoblasts apoptosis.

Objective: To investigate the in vitro effects of dehydroepiandrosterone (DHEA) on neonatal rat chondrocytes., Design: Chondrocytes isolated from neonatal rat cartilage were cultured in three-dimensionally agarose beads and were treated with DHEA., Methods: Primary culture of chondrocytes was harvested from newborn Wistar rats. The DHEA effects on chondrocyte activities were evaluated by analyzing chondrocyte proliferation, matrix protein synthesis, gene expressions of collagen, matrix metalloproteinase-1, -3 and -13 (MMP-1, -3 and -13), and cyclooxygenase-2 (COX-II), and protein synthesis of interleukin-6 (IL-6), prostaglandin E2 (PGE2) and tissue inhibitor of metalloproteinase-1 (TIMP-1)., Results: The DHEA treatment did affect chondrocyte proliferation and glycosaminoglycan (GAG) synthesis. DHEA suppressed the expression of MMP-1, -3 and -13 genes and PGE2 protein synthesis enhanced by lipopolysaccharide (LPS) while the COX-II and inducible nitric oxide synthase (iNOS) gene expressions were down-regulated by DHEA., Conclusions: Our study demonstrates that DHEA has an ability to modulate the imbalance between MMPs and PGE2 in the neonatal chondrocytes which suggest that it has a potential protective role against articular cartilage damage.

An in vitro bone cell culture model was used to evaluate the potential application of sintered beta-dicalcium pyrophosphate (SDCP) in arthroplasty surgery. Primary osteoclasts and osteoblasts were cocultured with different sizes of SDCP particles. The changes in cell counts and the synthesis and secretion of alkaline phosphatase, acid phosphatase, and prostaglandin E(2) in response to the SDCP particles were monitored. When bone cells were cultured with SDCP particles smaller than 53 microm, both the osteoblast and osteoclast cell counts decreased significantly. When the SDCP particles were larger than 177 microm, although the osteoblast population increased significantly, the osteoclast population decreased significantly. Simultaneously, the titer of prostaglandin E(2) in the medium and the cytoplasmic prostaglandin E(2) increased significantly. We concluded that SDCP is a potentially useful bioceramic for the prevention of osteoclast-mediated periprosthetic osteolysis., (Copyright 2003 Elsevier Inc. All rights reserved.)

Background: Avulsion fractures of the posterior cruciate ligament have long been regarded as rare injuries. In the past, it was common practice to use cast immobilization as an external adjunct after open reduction and internal fixation of fractures., Methods: Sixteen patients with displaced avulsion fractures of the posterior cruciate ligament were treated with open reduction and internal fixation between August 1989 and July 1993. Malleolar screws were chosen as fixation devices in 14 patients. In the other two, pull-through sutures were used because the size of the fractured fragments was too small to obtain purchase of screws. The postoperative management protocol evolved from an initial regimen of 6 weeks' immobilization in a cast with the knee flexed to 40 degrees for the first five patients (group I), to 4 weeks' immobilization in a cast for the next six patients (group II), to the present protocol of immediate postoperative range of motion (40-70 degrees) with muscle-strengthening exercises in a functional brace for the last five patients (group III). The average follow-up period was 36 months (range, 24-58 months). Hughston's criteria were used to assess the clinical results., Results: Overall, there were 12 (75%) good and 4 fair (25%) results. There was no poor result., Conclusion: Avulsion fractures of the posterior cruciate ligament should be treated with open reduction and stable internal fixation if any displacement is seen on initial radiographs at presentation. With the use of functional brace and aggressive postoperative rehabilitation program (i.e., immediate range of motion of 40-70 degrees with muscle-strengthening exercises), satisfactory results can be expected and achieved.

Bisphosphonates are synthetic pyrophosphate analogs that can be used for the treatment of osteoporosis. Sintered dicalcium pyrophosphate, as a pyrophosphate analog, may be useful in the clinical setting for osteoporosis. In this study, an ovariectomized rat model is used to evaluate the effects of orally administered sintered dicalcium pyrophosphate on bone mass. Thirty-six female rats were used in this study. They randomly were divided into six groups: a negative normal control group, a positive osteoporosis control group, and ovariectomized groups treated either with alendronate sodium (one group) or sintered dicalcium pyrophosphate (three groups, each at a different level). The animals were sacrificed at 4 weeks after treatment. For all the rats, whole blood samples were obtained for the biochemical study. Bone ashes of long bones were measured and studied and histologic studies of cancellous bone were carried out. The ingestion of either alendronate or sintered dicalcium pyrophosphate did not have any deleterious effect on the major visceral organs. Ingestion of alendronate or sintered pyrophosphate decreased the bony porosity and increased bone mineral contents in the long bones of ovariectomized rats. Thus sintered dicalcium pyrophosphate can increase bone mass in the ovariectomized rat., (Copyright 2001 John Wiley & Sons, Inc. J Biomed Mater Res 59: 246-253, 2002)