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Sample records for osteochondral implant coupled

  1. Mechanical and morphological evaluation of osteochondral implants in dogs.

    PubMed

    Bavaresco, Vanessa P; Garrido, Luiz; Batista, Nilza A; Malmonge, Sônia M; Belangero, William D

    2008-04-01

    The mechanical behavior of osteochondral defects was evaluated in this study with the intention of developing alternative procedures. Cylindrical pins (5.00 mm in diameter and in height) made of pHEMA hydrogel covered ultra-high molecular weight polyethylene (UHMWPE) or beta-tricalcium phosphate (beta-TCP) matrix were used. Ostoechondral defects were caused in the knees of adult dogs and the evaluation was carried out after a 9-month follow-up period. The mechanical behavior of the implants was evaluated by means of an indentation creep test that showed that the UHMWPE matrix maintained its viscoelastic behavior even after follow-up time, while the beta-TCP matrix osteochondral implants presented significant alterations. It is believed that the beta-TCP osteochondral implants were unable to withstand the load applied, causing an increase of complacency when compared to the UHMWPE osteochondral implants. Based on micro and macroscopic analysis, no significant wear was observed in either of the osteochondral implants when compared to the controls. However, morphological alterations, with fragmentation indices in the patella, were observed either due to friction with the hydrogel in the first postoperative months or due to forming of a dense conjunctive tissue. This wear mechanism caused on the counterface of the implant (patella) was observed, notwithstanding the osteochondral implant studied.

  2. Tissue engineering osteochondral implants for temporomandibular joint repair.

    PubMed

    Schek, R M; Taboas, J M; Hollister, S J; Krebsbach, P H

    2005-11-01

    Tissue engineering has provided an alternative to traditional strategies to repair and regenerate temporomandibular joints (TMJ). A successful strategy to engineer osteochondral tissue, such as that found in the TMJ, will produce tissue that is both biologically and mechanically functional. Image-based design (IBD) and solid free-form (SFF) fabrication can be used to generate scaffolds that are load bearing and match patient and defect site geometry. The objective of this study was to demonstrate how scaffold design, materials, and biological factors can be used in an integrated approach to regenerate a multi-tissue interface. IBD and SFF were first used to create biomimetic scaffolds with appropriate bulk geometry and microarchitecture. Biphasic composite scaffolds were then manufactured with the same techniques and used to simultaneously generate bone and cartilage in discrete regions and provide for the development of a stable interface between cartilage and subchondral bone. Poly-l-lactic acid/hydroxyapatite composite scaffolds were differentially seeded with fibroblasts transduced with an adenovirus expressing bone morphogenetic protein-7 in the ceramic phase and fully differentiated chondrocytes in the polymeric phase, and were subcutaneously implanted into mice. Following implantation in the ectopic site, the biphasic scaffolds promoted the simultaneous growth of bone, cartilage, and a mineralized interface tissue. Within the ceramic phase, the pockets of tissue generated included blood vessels, marrow stroma, and adipose tissue. This combination of IBD and SFF-fabricated biphasic scaffolds with gene and cell therapy is a promising approach to regenerate osteochondral defects and, ultimately, the TMJ.

  3. Clinical feasibility of a novel biphasic osteochondral composite for matrix-associated autologous chondrocyte implantation.

    PubMed

    Chiang, H; Liao, C-J; Hsieh, C-H; Shen, C-Y; Huang, Y-Y; Jiang, C-C

    2013-04-01

    Matrix-associated autologous chondrocyte implantation has been used to treat cartilage defects. We developed a biphasic cylindrical osteochondral composite construct for such use, and conducted this study to determine its feasibility for treating osteochondral lesions in human knees. Ten patients with symptomatic osteochondral lesions at femoral condyles were treated by replacing pathological tissue with the construct of dl-poly-lactide-co-glycolide, whose lower body was impregnated with β-tricalcium phosphate and served as osseous phase. The construct had a chamber to load double-minced autologous cartilage, serving as source of chondrocytes. Osteochondral lesion was drill-fashioned a pit of identical dimension as the construct. Chondrocyte-laden construct was press-fit to fill the pit. Postoperative outcome was evaluated using Knee Injury and Osteoarthritis Outcome Score (KOOS) scale up to 24 months. Magnetic resonance image was taken, and sample tissue was collected with second-look arthroscopic needle biopsy at 12 months. Outcome parameters were primarily safety of surgery, and secondarily postoperative change in KOOS and regeneration of hyaline cartilage and cancellous bone. No patient experienced serious adverse events. Postoperative mean KOOS in "symptoms" subscale had not changed significantly from pre-operation until 24 months; whereas those in the other four subscales were significantly higher than pre-operation at 12 and 24 months. Second-look arthroscopy showed completely filled grafted sites, with regenerate cartilaginous surfaces flushed with surrounding native joint surface. Microscopically, regenerated cartilage appeared hyaline. This novel construct for chondrocyte implantation is safe for surgical application in knee. It repairs osteochondral lesions of femoral condyles by successful regeneration of hyaline cartilage. Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  4. Evaluation of oriented electrospun fibers for periosteal flap regeneration in biomimetic triphasic osteochondral implant.

    PubMed

    Liu, Xudong; Liu, Shen; Liu, Shenghe; Cui, Wenguo

    2014-10-01

    Osteochondral defects represent a serious clinical problem. Although the cell-scaffold complexes have been reported to be effective for repairing osteochondral defects, a periosteal flap is frequently needed to arrest leakage of the implanted cells into the defect and to contribute to the secretion of cytokines to stimulate cartilage repair. The electrospun mesh mimicking the function of the flap assists tissue regeneration by preventing cell leakage and merits favorable outcomes in the cartilaginous region. In this study, an oriented poly(ε-caprolactone) (PCL) fibrous membrane (OEM) was fabricated by electrospinning as a periosteal scaffold and then freeze-dried with a collagen type I and hyaluronic acid cartilage scaffold (CH) and finally, freeze-dried with a tricalcium phosphate (TCP) bone substratum. Scanning electron microscopic images show obvious microstructure formation of the trilayered scaffolds, and electrospun fibrous membranes have an oriented fibrous network structure for the periosteal phase. Also shown are opened and interconnected pores with well designed three-dimensional structure, able to be bound in the CH (chondral phase) and TCP (osseous phase) scaffolds. In vitro results showed that the OEM can promote the orientation of bone marrow mesenchymal stem cell (BMSCs) and BMSCs can penetrate into the CH and TCP. After successfully combining the BMSCs, the tissue-engineered cartilage which contained the OEM and TCP complex was successfully used to regenerate the osteochondral defects in the rabbit model with greatly improved repair effects.

  5. Polyvinyl Alcohol Hydrogel Irradiated and Acetalized for Osteochondral Defect Repair: Mechanical, Chemical, and Histological Evaluation after Implantation in Rat Knees

    PubMed Central

    Batista, N. A.; Rodrigues, A. A.; Bavaresco, V. P.; Mariolani, J. R. L.; Belangero, W. D.

    2012-01-01

    Polyvinyl Alcohol (PVA) hydrogel plugs were implanted in artificial osteochondral defects on the trochlear groove of rat knees. After 0, 3, 6, 12, and 24 weeks of followup, samples containing the implants were mechanically evaluated by creep indentation test, chemically, and histologically by optical microscopy. The mechanical test pointed towards an increase of the implant creep modulus and the chemical analysis exhibited an increasing concentration of calcium and phosphorus within the implants over time. Optical microscopy showed no foreign body reaction and revealed formation, differentiation, and maintenance of new tissue at the defect/implant interface. The absence of implant wear indicated that the natural articular lubrication process was not disturbed by the implant. The performance of the irradiated and acetalized PVA was considered satisfactory for the proposed application. PMID:23197982

  6. Treatment of osteochondral defects of the talus with a metal resurfacing inlay implant after failed previous surgery: a prospective study.

    PubMed

    van Bergen, C J A; van Eekeren, I C M; Reilingh, M L; Sierevelt, I N; van Dijk, C N

    2013-12-01

    We have evaluated the clinical effectiveness of a metal resurfacing inlay implant for osteochondral defects of the medial talar dome after failed previous surgical treatment. We prospectively studied 20 consecutive patients with a mean age of 38 years (20 to 60), for a mean of three years (2 to 5) post-surgery. There was statistically significant reduction of pain in each of four situations (i.e., rest, walking, stair climbing and running; p ≤ 0.01). The median American Orthopaedic Foot and Ankle Society ankle-hindfoot score improved from 62 (interquartile range (IQR) 46 to 72) pre-operatively to 87 (IQR 75 to 95) at final follow-up (p < 0.001). The Foot and Ankle Outcome Score improved on all subscales (p ≤ 0.03). The mean Short-Form 36 physical component scale improved from 36 (23 to 50) pre-operatively to 45 (29 to 55) at final follow-up (p = 0.001); the mental component scale did not change significantly. On radiographs, progressive degenerative changes of the opposing tibial plafond were observed in two patients. One patient required additional surgery for the osteochondral defect. This study shows that a metal implant is a promising treatment for osteochondral defects of the medial talar dome after failed previous surgery.

  7. Microsphere-based gradient implants for osteochondral regeneration: a long-term study in sheep

    PubMed Central

    Mohan, Neethu; Gupta, Vineet; Sridharan, Banu Priya; Mellott, Adam J; Easley, Jeremiah T; Palmer, Ross H; Galbraith, Richard A; Key, Vincent H; Berkland, Cory J; Detamore, Michael S

    2015-01-01

    Background: The microfracture technique for cartilage repair has limited ability to regenerate hyaline cartilage. Aim: The current study made a direct comparison between microfracture and an osteochondral approach with microsphere-based gradient plugs. Materials & methods: The PLGA-based scaffolds had opposing gradients of chondroitin sulfate and β-tricalcium phosphate. A 1-year repair study in sheep was conducted. Results: The repair tissues in the microfracture were mostly fibrous and had scattered fissures with degenerative changes. Cartilage regenerated with the gradient plugs had equal or superior mechanical properties; had lacunated cells and stable matrix as in hyaline cartilage. Conclusion: This first report of gradient scaffolds in a long-term, large animal, osteochondral defect demonstrated potential for equal or better cartilage repair than microfracture. PMID:26418471

  8. Repair of superficial osteochondral defects with an autologous scaffold-free cartilage construct in a caprine model: implantation method and short-term results.

    PubMed

    Brehm, W; Aklin, B; Yamashita, T; Rieser, F; Trüb, T; Jakob, R P; Mainil-Varlet, P

    2006-12-01

    To compare four different implantation modalities for the repair of superficial osteochondral defects in a caprine model using autologous, scaffold-free, engineered cartilage constructs, and to describe the short-term outcome of successfully implanted constructs. Scaffold-free, autologous cartilage constructs were implanted within superficial osteochondral defects created in the stifle joints of nine adult goats. The implants were distributed between four 6-mm-diameter superficial osteochondral defects created in the trochlea femoris and secured in the defect using a covering periosteal flap (PF) alone or in combination with adhesives (platelet-rich plasma (PRP) or fibrin), or using PRP alone. Eight weeks after implantation surgery, the animals were killed. The defect sites were excised and subjected to macroscopic and histopathologic analyses. At 8 weeks, implants that had been held in place exclusively with a PF were well integrated both laterally and basally. The repair tissue manifested an architecture similar to that of hyaline articular cartilage. However, most of the implants that had been glued in place in the absence of a PF were lost during the initial 4-week phase of restricted joint movement. The use of human fibrin glue (FG) led to massive cell infiltration of the subchondral bone. The implantation of autologous, scaffold-free, engineered cartilage constructs might best be performed beneath a PF without the use of tissue adhesives. Successfully implanted constructs showed hyaline-like characteristics in adult goats within 2 months. Long-term animal studies and pilot clinical trials are now needed to evaluate the efficacy of this treatment strategy.

  9. Acid ceramidase treatment enhances the outcome of autologous chondrocyte implantation in a rat osteochondral defect model.

    PubMed

    Frohbergh, M E; Guevara, J M; Grelsamer, R P; Barbe, M F; He, X; Simonaro, C M; Schuchman, E H

    2016-04-01

    The overall aim of this study was to evaluate how supplementation of chondrocyte media with recombinant acid ceramidase (rhAC) influenced cartilage repair in a rat osteochondral defect model. Primary chondrocytes were grown as monolayers in polystyrene culture dishes with and without rhAC (added once at the time of cell plating) for 7 days, and then seeded onto Bio-Gide® collagen scaffolds and grown for an additional 3 days. The scaffolds were then introduced into osteochondral defects created in Sprague-Dawley rat trochlea by a microdrilling procedure. Analysis was performed 6 weeks post-surgery macroscopically, by micro-CT, histologically, and by immunohistochemistry. Treatment with rhAC led to increased cell numbers and glycosaminoglycan (GAG) production (∼2 and 3-fold, respectively) following 7 days of expansion in vitro. Gene expression of collagen 2, aggrecan and Sox-9 also was significantly elevated. After seeding onto Bio-Gide®, more rhAC treated cells were evident within 4 h. At 6 weeks post-surgery, defects containing rhAC-treated cells exhibited more soft tissue formation at the articular surface, as evidenced by microCT, as well as histological evidence of enhanced cartilage repair. Notably, collagen 2 immunostaining revealed greater surface expression in animals receiving rhAC treated cells as well. Collagen 10 staining was not enhanced. The results further demonstrate the positive effects of rhAC treatment on chondrocyte growth and phenotype in vitro, and reveal for the first time the in vivo effects of the treated cells on cartilage repair. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  10. Osteochondritis Dissecans

    MedlinePlus

    ... symptom of osteochondritis dissecans might be triggered by physical activity — walking up stairs, climbing a hill or playing sports. Swelling and tenderness. The skin around your joint might be swollen and tender. ...

  11. Osteochondral Allograft of the Talus

    PubMed Central

    Bisicchia, Salvatore; Rosso, Federica; Amendola, Annunziato

    2014-01-01

    Osteochondral lesions of the talus are being recognized as an increasingly common injury. They are most commonly located postero-medially or antero-laterally, while centrally located lesions are uncommon. Large osteochondral lesions have significant biomechanical consequences and often require resurfacing with osteochondral autograft transfer, mosaicplasty, autologous chondrocyte implantation (or similar methods) or osteochondral allograft transplantation. Allograft procedures have become popular due to inherent advantages over other resurfacing techniques. Cartilage viability is one of the most important factors for successful clinical outcomes after transplantation of osteochondral allografts and is related to storage length and intra-operative factors. While there is abundant literature about osteochondral allograft transplantation in the knee, there are few papers about this procedure in the talus. Failure of non-operative management, initial debridement, curettage or microfractures are an indication for resurfacing. Patients should have a functional ankle motion, closed growth plates, absence of cartilage lesions on the tibial side. This paper reviews the published literature about osteochondral allograft transplantation of the talus focusing on indications, pre-operative planning, surgical approaches, postoperative management, results and complications of this procedure. PMID:25328456

  12. Acid Ceramidase Treatment Enhances the Outcome of Autologous Chondrocyte Implantation in a Rat Osteochondral Defect Model

    PubMed Central

    Frohbergh, Michael E.; Guevara, Johana M.; Grelsamer, Ronald P.; Barbe, Mary F.; He, Xingxuan; Simonaro, Calogera M.; Schuchman, Edward H.

    2015-01-01

    Objective The overall aim of this study was to evaluate how supplementation of chondrocyte media with recombinant acid ceramidase (rhAC) influenced cartilage repair in a rat osteochondral defect model. Methods Primary chondrocytes were grown as monolayers in polystyrene culture dishes with and without rhAC (added once at the time of cell plating) for 7 days, and then seeded onto Bio-Gide® collagen scaffolds and grown for an additional 3 days. The scaffolds were then introduced into osteochondroal defects created in Sprague-Dawley rat trochlea by a micordrilling procedure. Analysis was performed 6 weeks post-surgery macroscopically, by micro-CT, histologically, and by immunohistochemistry. Results Treatment with rhAC led to increased cell numbers and glycosaminoglycan production (~2 and 3-fold, respectively) following 7 days of expansion in vitro. Gene expression of collagen 2, aggrecan and Sox-9 also was significantly elevated. After seeding onto Bio-Gide®, more rhAC treated cells were evident within 4 hours. At 6 weeks post-surgery, defects containing rhAC-treated cells exhibited more soft tissue formation at the articular surface, as evidenced by microCT, as well as histological evidence of enhanced cartilage repair. Notably, collagen 2 immunostaining revealed greater surface expression in animals receiving rhAC treated cells as well. Collagen 10 staining was not enhanced. Conclusion The results further demonstrate the positive effects of rhAC treatment on chondrocyte growth and phenotype in vitro, and reveal for the first time the in vivo effects of the treated cells on cartilage repair. PMID:26524412

  13. Biological and functional evaluation of a novel pyrolytic carbon implant for the treatment of focal osteochondral defects in the medial femoral condyle: assessment in a canine model.

    PubMed

    Salkeld, Samantha L; Patron, Laura P; Lien, Joan C; Cook, Stephen D; Jones, Deryk G

    2016-12-01

    Osteochondral defects continue to be a clinical treatment challenge, and when left untreated, may cause pain and functional impairment. Pyrolytic carbon is a unique isotropic biomaterial used in heart valve and small joint replacements due to its excellent wear properties and biocompatibility with bone and articular cartilage. Therefore, a proposed solution is to utilize a focal pyrolytic carbon hemiarthroplasty implant as an alternative resurfacing treatment strategy for isolated cartilage lesions. A canine model (n = 9) was used to evaluate the in vivo histologic response and function of a pyrolytic carbon implant replacing a full-thickness osteochondral defect in the medial femoral condyle (MFC) of the knee. The gross appearance and histologic results were compared to an identical cobalt-chromium (Co-Cr) alloy implant placed in a defect in the contralateral MFC and evaluated up to 52 weeks. Extensive bone incorporation to the stem portion was observed for both implant types. The total mean histologic score for the cartilage of the MFC surrounding the pyrolytic carbon implants was significantly improved compared to that of the Co-Cr alloy implants at all evaluation periods (p < 0.05). Histologic grading and gross observations at 52 weeks for pyrolytic carbon implants were similar to those of Co-Cr alloy implants at 24 weeks. At 24 weeks, the mean total histologic score for Co-Cr alloy implants was 11.6 ± 0.7 (0-16 range point; 16 = normal appearance), while at 52 weeks, the mean total score for the pyrolytic carbon implants was 11.7 ± 1.3. Mean total histologic score of opposing medial tibia cartilage for the pyrolytic carbon implants was superior to that of the Co-Cr alloy group at all evaluation periods and significantly improved over the Co-Cr alloy implant group at 24 weeks (p = 0.001) and 52 weeks (p < 0.001). Use of a pyrolytic carbon implant for reconstruction of a focal cartilage defect demonstrated effective implant

  14. Results of HemiCAP(®) Implantation as a Salvage Procedure for Osteochondral Lesions of the Talus.

    PubMed

    Ettinger, Sarah; Stukenborg-Colsman, Christina; Waizy, Hazibullah; Becher, Christoph; Yao, Daiwei; Claassen, Leif; Noll, Yvonne; Plaass, Christian

    Osteochondral defects (OCDs) of the talus remain a surgical challenge, especially after failed primary treatment. The aim of the present study was to examine the clinical outcomes after HemiCAP(®) implantation for OCDs of the medial talar dome after failed previous surgery. Our retrospective study included 11 patients, who had undergone surgery from June 2009 to September 2012 for an OCD of the medial talar dome and received a HemiCAP(®) on the talus after failed previous surgery for OCD. The data were acquired using patients' medical records and standardized questionnaires, including the Foot and Ankle Outcome Score (FAOS), University of California at Los Angeles (UCLA) activity score, EQ-5D, numerical rating scale (NRS), and Short-Form 36-item Health Survey (SF-36). Using these scores, the possibility of returning to work and sports was determined. Any complications and the need for revision surgery were recorded. One patient refused to participate in the study, leaving 10 patients for evaluation. The mean age was 47.64 ± 10.97 years. The mean follow-up period was 43.5 ± 35.51 months. The FAOS and SF-36 subscale scores and the EQ-5D and UCLA activity scores did not improve significantly (p < .05). The mean postoperative pain score on the NRS improved significantly from 6.6 ± 1.77 preoperatively to 5.1 ± 2.02 postoperatively (p < .05). A greater body mass index led to worse postoperative outcomes with higher scores on the pain-NRS and less satisfaction (p < .05). Ten revisions for ongoing pain were performed in 7 patients (70.0%) within a mean of 28.4 ± 13.35 months of the initial procedure, and 6 patients (60%) indicated they would undergo surgery again. The results of the present study have shown that implantation of the HemiCAP(®) as a salvage procedure for OCDs of the talus is challenging and does not consistently lead to good clinical results. Also, overweight patients appear to have an increased risk of postoperative

  15. Osteochondral repair using a scaffold-free tissue-engineered construct derived from synovial mesenchymal stem cells and a hydroxyapatite-based artificial bone.

    PubMed

    Shimomura, Kazunori; Moriguchi, Yu; Ando, Wataru; Nansai, Ryosuke; Fujie, Hiromichi; Hart, David A; Gobbi, Alberto; Kita, Keisuke; Horibe, Shuji; Shino, Konsei; Yoshikawa, Hideki; Nakamura, Norimasa

    2014-09-01

    For an ideal osteochondral repair, it is important to facilitate zonal restoration of the subchondral bone and the cartilage, layer by layer. Specifically, restoration of the osteochondral junction and secure integration with adjacent cartilage could be considered key factors. The purpose of the present study was to investigate the feasibility of a combined material comprising a scaffold-free tissue-engineered construct (TEC) derived from synovial mesenchymal stem cells (MSCs) and a hydroxyapatite (HA) artificial bone using a rabbit osteochondral defect model. Osteochondral defects were created on the femoral groove of skeletally mature rabbits. The TEC and HA artificial bone were hybridized to develop a combined implant just before use, which was then implanted into defects (N=23). In the control group, HA alone was implanted (N=18). Histological evaluation and micro-indentation testing was performed for the evaluation of repair tissue. Normal knees were used as an additional control group for biomechanical testing (N=5). At hybridization, the TEC rapidly attached onto the surface of HA artificial bone block, which was implantable to osteochondral defects. Osteochondral defects treated with the combined implants exhibited more rapid subchondral bone repair coupled with the development of cartilaginous tissue with good tissue integration to the adjacent host cartilage when assessed at 6 months post implantation. Conversely, the control group exhibited delayed subchondral bone repair. In addition, the repair cartilaginous tissue in this group had poor integration to adjacent cartilage and contained clustered chondrocytes, suggesting an early osteoarthritis (OA)-like degenerative change at 6 months post implantation. Biomechanically, the osteochondral repair tissue treated with the combined implants at 6 months restored tissue stiffness, similar to normal osteochondral tissue. The combined implants significantly accelerated and improved osteochondral repair

  16. Matrix generation within a macroporous non-degradable implant for osteochondral defects is not enhanced with partial enzymatic digestion of the surrounding tissue: evaluation in an in vivo rabbit model.

    PubMed

    Krych, Aaron J; Wanivenhaus, Florian; Ng, Kenneth W; Doty, Stephen; Warren, Russell F; Maher, Suzanne A

    2013-10-01

    Articular cartilage defects are a significant source of pain, have limited ability to heal, and can lead to the development of osteoarthritis. However, a surgical solution is not available. To tackle this clinical problem, non-degradable implants capable of carrying mechanical load immediately after implantation and for the duration of implantation, while integrating with the host tissue, may be viable option. But integration between articular cartilage and non-degradable implants is not well studied. Our objective was to assess the in vivo performance of a novel macroporous, nondegradable, polyvinyl alcohol construct. We hypothesized that matrix generation within the implant would be enhanced with partial digestion of the edges of articular cartilage. Our hypothesis was tested by randomizing an osteochondral defect created in the trochlea of 14 New Zealand white rabbits to treatment with: (i) collagenase or (ii) saline, prior to insertion of the implant. At 1 and 3-month post-operatively, the gross morphology and histologic appearance of the implants and the surrounding tissue were assessed. At 3 months, the mechanical properties of the implant were also quantified. Overall, the hydrogel implants performed favorably; at all time-points and in all groups the implants remained well fixed, did not cause inflammation or synovitis, and did not cause extensive damage to the opposing articular cartilage. Regardless of treatment with saline or collagenase, at 1 month post-operatively implants from both groups had a contiguous interface with adjacent cartilage and were populated with chondrocyte-like cells. At 3 months fibrous encapsulation of all implants was evident, there was no difference between area of aggrecan staining in the collagenase versus saline groups, and implant modulus was similar in both groups; leading us to reject our hypothesis. In summary, a porous PVA osteochondral implant remained well fixed in a short term in vivo osteochondral defect model

  17. Intra-articular administration of hyaluronic acid increases the volume of the hyaline cartilage regenerated in a large osteochondral defect by implantation of a double-network gel.

    PubMed

    Fukui, Takaaki; Kitamura, Nobuto; Kurokawa, Takayuki; Yokota, Masashi; Kondo, Eiji; Gong, Jian Ping; Yasuda, Kazunori

    2014-04-01

    Implantation of PAMPS/PDMAAm double-network (DN) gel can induce hyaline cartilage regeneration in the osteochondral defect. However, it is a problem that the volume of the regenerated cartilage tissue is gradually reduced at 12 weeks. This study investigated whether intra-articular administration of hyaluronic acid (HA) increases the volume of the cartilage regenerated with the DN gel at 12 weeks. A total of 48 rabbits were used in this study. A cylindrical osteochondral defect created in the bilateral femoral trochlea was treated with DN gel (Group DN) or left without any implantation (Group C). In both Groups, we injected 1.0 mL of HA in the left knee, and 1.0 mL of saline solution in the right knee. Quantitative histological evaluations were performed at 2, 4, and 12 weeks, and PCR analysis was performed at 2 and 4 weeks after surgery. In Group DN, the proteoglycan-rich area was significantly greater in the HA-injected knees than in the saline-injected knees at 12 weeks (P = 0.0247), and expression of type 2 collagen, aggrecan, and Sox9 mRNAs was significantly greater in the HA-injected knees than in the saline-injected knees at 2 weeks (P = 0.0475, P = 0.0257, P = 0.0222, respectively). The intra-articular administration of HA significantly enhanced these gene expression at 2 weeks and significantly increased the volume of the hyaline cartilage regenerated by implantation of a DN gel at 12 weeks. This information is important to develop an additional method to increase the volume of the hyaline cartilage tissue in a potential cartilage regeneration strategy using the DN gel.

  18. Arthroscopic treatment of osteochondral lesions of the ankle with matrix-associated chondrocyte implantation: early clinical and magnetic resonance imaging results.

    PubMed

    Aurich, Matthias; Bedi, Harvinder S; Smith, Peter J; Rolauffs, Bernd; Mückley, Thomas; Clayton, James; Blackney, Mark

    2011-02-01

    Conventional autologous chondrocyte transplantation in the ankle often requires tibial or fibular osteotomies with potential morbidity for the patient. Advances in biotechnology and surgical techniques have resulted in the development of matrix-associated chondrocyte implantation (MACI). As the chondrocyte-loaded scaffold can be applied arthroscopically, this procedure is especially useful for the treatment of osteochondral defects in the ankle. Arthroscopic MACI is a safe procedure in the ankle with good clinical and magnetic resonance imaging results. Case series; Level of evidence, 4. The authors reviewed all patients (n = 18) who had arthroscopic MACI for osteochondral lesions of the ankle (n = 19) between February 2006 and May 2008 clinically and with magnetic resonance imaging. The pain and disability module of the Foot Function Index (FFI), the American Orthopaedic Foot & Ankle Society (AOFAS) clinical rating system, the Core Scale of the Foot and Ankle Module of the American Academy of Orthopaedic Surgeons (AAOS) Lower Limb Outcomes Assessment Instruments, and the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score were used. The clinical results up to 3 years after MACI (mean follow-up, 24.5 months) were compared with preoperative data for 14 cases and the magnetic resonance imaging data for all 19. A significant improvement (50.3% ± 13.2%) in all clinical scores was noted (FFI pain before MACI: 5.5 ± 2.0, after MACI: 2.8 ± 2.2; FFI disability before MACI: 5.0 ± 2.3, after MACI: 2.6 ± 2.2; AOFAS before MACI: 58.6 ± 16.1, after MACI: 80.4 ± 14.1; AAOS standardized mean before MACI: 59.9 ± 16.0, after MACI: 83.5 ± 13.2; AAOS normative score before MACI: 23.0 ± 13.0, after MACI: 42.2 ± 10.7). According to the AOFAS Hindfoot score, 64% were rated as excellent and good, whereas 36% were rated fair and poor. The results correlated with the age of the patient and the duration of symptoms, but not with the size of the lesion

  19. Osteochondritis dissecans of the talus

    PubMed Central

    ZANON, GIACOMO; DI VICO, GIOVANNI; MARULLO, MATTEO

    2014-01-01

    Osteochondritis dissecans (OCD) is an acquired idiopathic lesion of subchondral bone that can produce delamination and sequestration with or without articular cartilage involvement and instability. The cause of OCD is still debated: the most recognized etiology is the occurrence of repetitive micro-traumas associated with vascular impairment, causing progressive ankle pain and dysfunction in skeletally immature and young adult patients. Ankle OCD is classically located in the medial part of the talus, while lateral and posterior involvement is less frequent. Diagnosis of OCD, based on MRI findings, is quite straightforward; MRI examination can also be very useful for dating the defect and obtaining information about the associated bone bruise. Osteochondritis dissecans, if not recognized and treated appropriately, may lead to secondary osteoarthritis with pain and functional limitation. Surgical treatment is mandatory especially in young patients with unstable cartilage fragments. There are various surgical options: fixation, microfracture, or substitution using autologous chondrocyte implantation techniques. PMID:25606554

  20. Microdrilled cartilage defects treated with thrombin-solidified chitosan/blood implant regenerate a more hyaline, stable, and structurally integrated osteochondral unit compared to drilled controls.

    PubMed

    Marchand, Catherine; Chen, Gaoping; Tran-Khanh, Nicolas; Sun, Jun; Chen, Hongmei; Buschmann, Michael D; Hoemann, Caroline D

    2012-03-01

    controls, chitosan implants solidified with thrombin elicited a more hyaline and structurally integrated osteochondral unit, features needed for long-term durability.

  1. Osteochondritis Dissecans (OCD)

    MedlinePlus

    ... mice, motion, necrosis, osteochondritis, osteochondroses, pain, repetitive, sticking, stress, subchondral Family Health, Kids and Teens, Men September 2000 Copyright © American Academy of Family ...

  2. [Chondral and osteochondral fractures].

    PubMed

    Kayaoğlu, E Esin; Binnet, Mehmet S

    2007-01-01

    The incidence of traumatic chondral and osteochondral fractures and their role in the development of joint degeneration are not fully elucidated. While assessing traumatic knee injuries, one important criterion for the diagnosis of chondral fractures is to remember the possibility of a chondral or osteochondral fracture. Symptoms in osteochondral fractures are more obvious and cause severe pain and difficulty in movement of knee with hemarthrosis. The presence of hemarthrosis facilitates the diagnosis of an osteochondral fracture. Chondral and osteochondral fractures may be associated with other intra-articular pathologies. There are two main mechanisms of these fractures, including a direct effect causing avulsion or impaction and, a more common mechanism, flexion-rotation force to the knee, which is also the mechanism for an acute patellar dislocation. It is known that arthroscopic treatment is the best method for the diagnosis and treatment of chondral and osteochondral fractures. In osteochondral lesions, the aim of treatment is to restore the congruity of articular surfaces. In agreement with literature data, our clinical experience favors internal fixation as the most effective method for the treatment of osteochondral fractures.

  3. Porous titanium bases for osteochondral tissue engineering

    PubMed Central

    Nover, Adam B.; Lee, Stephanie L.; Georgescu, Maria S.; Howard, Daniel R.; Saunders, Reuben A.; Yu, William T.; Klein, Robert W.; Napolitano, Anthony P.; Ateshian, Gerard A.

    2015-01-01

    Tissue engineering of osteochondral grafts may offer a cell-based alternative to native allografts, which are in short supply. Previous studies promote the fabrication of grafts consisting of a viable cell-seeded hydrogel integrated atop a porous, bone-like metal. Advantages of the manufacturing process have led to the evaluation of porous titanium as the bone-like base material. Here, porous titanium was shown to support the growth of cartilage to produce native levels of Young’s modulus, using a clinically relevant cell source. Mechanical and biochemical properties were similar or higher for the osteochondral constructs compared to chondral-only controls. Further investigation into the mechanical influence of the base on the composite material suggests that underlying pores may decrease interstitial fluid pressurization and applied strains, which may be overcome by alterations to the base structure. Future studies aim to optimize titanium-based tissue engineered osteochondral constructs to best match the structural architecture and strength of native grafts. Statement of Significance The studies described in this manuscript follow up on previous studies from our lab pertaining to the fabrication of osteochondral grafts that consist of a bone-like porous metal and a chondrocyte-seeded hydrogel. Here, tissue engineered osteochondral grafts were cultured to native stiffness using adult chondrocytes, a clinically relevant cell source, and a porous titanium base, a material currently used in clinical implants. This porous titanium is manufactured via selective laser melting, offering the advantages of precise control over shape, pore size, and orientation. Additionally, this manuscript describes the mechanical influence of the porous base, which may have applicability to porous bases derived from other materials. PMID:26320541

  4. Refixation of osteochondral fractures by ultrasound-activated, resorbable pins

    PubMed Central

    Neumann, H.; Schulz, A. P.; Gille, J.; Klinger, M.; Jürgens, C.; Reimers, N.; Kienast, B.

    2013-01-01

    Objectives Osteochondral injuries, if not treated adequately, often lead to severe osteoarthritis. Possible treatment options include refixation of the fragment or replacement therapies such as Pridie drilling, microfracture or osteochondral grafts, all of which have certain disadvantages. Only refixation of the fragment can produce a smooth and resilient joint surface. The aim of this study was the evaluation of an ultrasound-activated bioresorbable pin for the refixation of osteochondral fragments under physiological conditions. Methods In 16 Merino sheep, specific osteochondral fragments of the medial femoral condyle were produced and refixed with one of conventional bioresorbable pins, titanium screws or ultrasound-activated pins. Macro- and microscopic scoring was undertaken after three months. Results The healing ratio with ultrasound-activated pins was higher than with conventional pins. No negative heat effect on cartilage has been shown. Conclusion As the material is bioresorbable, no further surgery is required to remove the implant. MRI imaging is not compromised, as it is with implanted screws. The use of bioresorbable pins using ultrasound is a promising technology for the refixation of osteochondral fractures. PMID:23610699

  5. Influence of the gel thickness on in vivo hyaline cartilage regeneration induced by double-network gel implanted at the bottom of a large osteochondral defect: short-term results.

    PubMed

    Matsuda, Hidetoshi; Kitamura, Nobuto; Kurokawa, Takayuki; Arakaki, Kazunobu; Gong, Jian Ping; Kanaya, Fuminori; Yasuda, Kazunori

    2013-01-31

    A double-network (DN) gel, which is composed of poly(2-acrylamido-2-methylpropanesulfonic acid) and poly(N,N'-dimethyl acrylamide), can induce hyaline cartilage regeneration in vivo in a large osteochondral defect. The purpose of this study was to clarify the influence of the thickness of the implanted DN gel on the induction ability of hyaline cartilage regeneration. Thirty-eight mature rabbits were used in this study. We created an osteochondral defect having a diameter of 4.3-mm in the patellofemoral joint. The knees were randomly divided into 4 groups (Group I: 0.5-mm thick gel, Group II: 1.0-mm thick gel, Group III: 5.0-mm thick gel, and Group IV: untreated control). Animals in each group were further divided into 3 sub-groups depending on the gel implant position (2.0-, 3.0-, or 4.0-mm depth from the articular surface) in the defect. The regenerated tissues were evaluated with the Wayne's gross and histological grading scales and real time PCR analysis of the cartilage marker genes at 4 weeks. According to the total Wayne's score, when the depth of the final vacant space was set at 2.0 mm, the scores in Groups I, II, and III were significantly greater than that Group IV (p<0.05), although there were no significant differences between Groups I and IV at a 3.0-mm deep vacant space. The expression levels of type-2 collagen in Groups II and III were significantly higher (p<0.05) than that in Group IV. The 1.0-mm thick DN gel sheet had the same ability to induce hyaline cartilage regeneration as the 5.0-mm thick DN gel plug. However, the induction ability of the 0.5-mm thick sheet was significantly lower when compared with the 1.0-mm thick gel sheet. The 1.0-mm DN gel sheet is a promising device to establish a cell-free cartilage regeneration strategy that minimizes bone loss from the gel implantation.

  6. Electrochemical properties of suprastructures galvanically coupled to a titanium implant.

    PubMed

    Oh, Keun-Taek; Kim, Kyoung-Nam

    2004-08-15

    In recent years, dental implants have been widely used for the aesthetic and functional restoration of edentulous patients. Dental implants and restorative alloys are required with high corrosion resistance. Suprastructures and implants of different compositions in electrical contact may develop galvanic or coupled corrosion problems. In addition to galvanic corrosion, crevice and pitting corrosion may occur in the marginal gap between dental implant assemblies. In this study, gold, silver-palladium, cobalt-chromium, and nickel-chromium suprastructures were used to investigate their galvanic and crevice corrosion characteristics in combination with titanium (Ti) implants. Potentiodynamic and potentiostatic testing were performed in artificial saliva at 37 degrees C. Potentiodynamic testing was carried out at the potential scan rate of 1 mV/s in the range of -600-1600 mV (SCE). Potentiostatic testing was performed with an open-circuit potential and current densities at -250, 0, and 250 mV (SCE) in artificial saliva. After electrochemical testing, surface morphologies and cross-sections were examined using micrographs of the samples. Potentiodynamic test results indicated that suprastructure/Ti implant couples produced passive current densities in the range of 0.5-12 microA/cm(2); Ti abutment/Ti implant and gold/Ti implant couples exhibited relatively low passive current densities; Co-Cr/Ti implant couples the highest. Co-Cr and Ni-Cr/Ti implant couples showed breakdown potentials of 700 and 570 mV (SCE), respectively. The open-circuit potentials of silver, Ti abutment, gold, Ni-Cr, and Co-Cr/Ti implant couples were -93.2 +/- 93.9, -123.7 +/- 58.8, -140.0 +/- 80.6, -223.5 +/- 35.1, and -312.7 +/- 29.8 mV (SCE), respectively, and did not change with immersion time. The couples exhibited cathodic current densities at -250 mV (SCE); in particular, gold and silver alloys showed high cathodic current densities of -3.18 and -6.63 microA/cm(2), respectively. At 250 mV (SCE

  7. Treatment of osteochondral injuries. Genetic engineering.

    PubMed

    Martinek, V; Fu, F H; Lee, C W; Huard, J

    2001-04-01

    Articular cartilage injuries are commonly encountered problems in sports medicine and orthopaedics. The treatment of chondral and osteochondral lesions, which possess only a very limited potential for healing, still represents a great challenge to clinicians and to scientists. Experimental investigations reported over the last 20 years have shown that a variety of methods, including implantation of periosteum, perichondrium, artificial matrices, growth factors, and transplanted cells, can stimulate formation of new cartilage. Genetic engineering--a combination of gene transfer techniques and tissue engineering--will facilitate new approaches to the treatment of articular cartilage injuries.

  8. Fabrication of tissue engineered osteochondral grafts for restoring the articular surface of diarthrodial joints

    PubMed Central

    Roach, Brendan L.; Hung, Clark T.; Cook, James L.; Ateshian, Gerard A.; Tan, Andrea R.

    2015-01-01

    Osteochondral allograft implantation is an effective cartilage restoration technique for large defects (>10 cm2), though the demand far exceeds the supply of available quality donor tissue. Large bilayered engineered cartilage tissue constructs with accurate anatomical features (i.e. contours, thickness, architecture) could be beneficial in replacing damaged tissue. When creating these osteochondral constructs, however, it is pertinent to maintain biofidelity to restore functionality. Here, we describe a step-by-step framework for the fabrication of a large osteochondral construct with correct anatomical architecture and topology through a combination of high-resolution imaging, rapid prototyping, impression molding, and injection molding. PMID:25794950

  9. Gamete cytogenetic study in couples with implantation failure: aneuploidy rate is increased in both couple members

    PubMed Central

    Hammoud, I.; Molina-Gomes, D.; Wainer, R.; Bergere, M.; Albert, M.; Bailly, M.; de Mazancourt, P.; Selva, J.

    2008-01-01

    Purpose Implantation failure is known to be associated with an increased risk of aneuploidy in embryos, a situation leading to a pre-implantation genetic screening, not allowed in different countries like France. Our aim was to evaluate the gamete aneuploidy incidence in this context, using first polar body and spermatozoa aneuploidy screening. Methods Three groups were considered: 11 couples with pregnancy obtained after IVF for female infertility (group 1); 20 couples with pregnancy obtained after IVF for male infertility (group 2); and 35 couples with implantation failure (group 3). In group 3, 28 couples treated by ICSI volunteered for first polar body analysis (PB1). Results Spermatozoa aneuploidy rate was increased in groups 2 (1.6%) and 3 (2.1%) in comparison to group 1 (0.6%). PB1 aneuploidy rate was 35.4% in group 3. Finally, eight couples (32%) had no particular chromosomal risk in gametes, 15/25 (60%) presented an increased spermatic (>2%) or oocyte (>1/3) aneuploidy rate, and 2/25 (8%) had both. Conclusion Those results confirm that implantation failure has a heterogeneous origin, that gamete chromosome abnormality rate is one of the major contributing factors, and that 1st Polar body and spermatozoa aneuploidy screening or pre-implantation genetics screening may be indicated for these couples. PMID:18972203

  10. Evaluation and Management of Osteochondral Lesions of the Talus

    PubMed Central

    Looze, Christopher A.; Capo, Jason; Ryan, Michael K.; Begly, John P.; Chapman, Cary; Swanson, David; Singh, Brian C.; Strauss, Eric J.

    2016-01-01

    Osteochondral lesions of the talus are common injuries that affect a wide variety of active patients. The majority of these lesions are associated with ankle sprains and fractures though several nontraumatic etiologies have also been recognized. Patients normally present with a history of prior ankle injury and/or instability. In addition to standard ankle radiographs, magnetic resonance imaging and computed tomography are used to characterize the extent of the lesion and involvement of the subchondral bone. Symptomatic nondisplaced lesions can often be treated conservatively within the pediatric population though this treatment is less successful in adults. Bone marrow stimulation techniques such as microfracture have yielded favorable results for the treatment of small (<15 mm) lesions. Osteochondral autograft can be harvested most commonly from the ipsilateral knee and carries the benefit of repairing defects with native hyaline cartilage. Osteochondral allograft transplant is reserved for large cystic lesions that lack subchondral bone integrity. Cell-based repair techniques such as autologous chondrocyte implantation and matrix-associated chondrocyte implantation have been increasingly used in an attempt to repair the lesion with hyaline cartilage though these techniques require adequate subchondral bone. Biological agents such as platelet-rich plasma and bone marrow aspirate have been more recently studied as an adjunct to operative treatment but their use remains theoretical. The present article reviews the current concepts in the evaluation and management of osteochondral lesions of the talus, with a focus on the available surgical treatment options. PMID:27994717

  11. How I Manage Osteochondritis Dissecans.

    ERIC Educational Resources Information Center

    DiStefano, Vincent J.

    1986-01-01

    Osteochondritis dissecans, a lesion found most often on the femur at the knee joint, occurs most frequently in active adolescents. This article describes treatment for preadolescents, adolescents, and adults. Osteochondritus dissecans of the patella is also presented. (MT)

  12. How I Manage Osteochondritis Dissecans.

    ERIC Educational Resources Information Center

    DiStefano, Vincent J.

    1986-01-01

    Osteochondritis dissecans, a lesion found most often on the femur at the knee joint, occurs most frequently in active adolescents. This article describes treatment for preadolescents, adolescents, and adults. Osteochondritus dissecans of the patella is also presented. (MT)

  13. Corrosion investigation of two materials for implant supraconstructions coupled to a titanium implant.

    PubMed

    Ravnholt, G; Jensen, J

    1991-04-01

    The corrosion of two materials for implant supraconstructions, a carbon fiber/PMMA composite and a silver-palladium alloy, was investigated in vitro, the materials being galvanically coupled to a titanium implant. Corrosion current and pH of the electrolyte were monitored, and corrosion products were identified by powder X-ray diffraction. The carbon composite and the silver-palladium per se did not corrode, whereas a silver-palladium specimen brazed with the recommended brazing alloy corroded unmistakably, yielding copper-containing corrosion products. The action of local corrosion cells around the brazed joint is considered, and it is concluded that the two materials seem well suited for implant supraconstructions, provided that brazing the silver-palladium can be avoided. Considering the clinical relevance of the experimental model used, it is concluded that the model is likely to predict a lower corrosion susceptibility than the one found in vivo.

  14. OSTEOCHONDRITIS DISSECANS OF THE KNEE: DIAGNOSIS AND TREATMENT

    PubMed Central

    Mestriner, Luiz Aurélio

    2015-01-01

    Osteochondritis dissecans (OCD) is a pathological process affecting the subchondral bone of the knee in children and adolescents with open growth plates (juvenile OCD) and young adults with closed growth plates (adult OCD). It may lead to secondary effects on joint cartilage, such as pain, edema, possible formation of free bodies and mechanical symptoms, including joint locking. OCD may lead to degenerative changes may develop if left untreated. This article presents a review and update on this problem, with special emphasis on diagnosis and treatment. The latter may include either conservative methods, which show more predictable results for juvenile OCD, or various surgical methods, which include reparative techniques like isolated removal of the fragment, bone drilling and fixation of the osteochondral fragments, and restorative techniques like microfractures, autologous osteochondral transplantation (mosaicplasty), autologous chondrocyte implantation and fresh osteochondral allograft, depending on lesion stability, lesion viability, skeletal maturity and OCD process location. Recent assessments on the results from several types of treatment have shown that there is a lack of studies with reliable levels of evidence and have suggested that further multicenter prospective randomized and controlled studies on management of this disease should be conducted. PMID:27047865

  15. Osteochondral lesions of the talus: Current concept.

    PubMed

    Laffenêtre, O

    2010-09-01

    Osteochondral lesions of the talus (OTL) are among those injuries that we should not fail to recognize, especially following any type of hindfoot injury. They were thoroughly described 15 years ago in a round table session organized by Doré and Rosset for the Société orthopédique de l'Ouest. Their physiopathology has not yet been definitely determined, even though some of the pathogenic mechanisms are known. They are best characterized using the fractures, osteonecroses, geodes (FOG) radiological classification. Both their diagnosis and their surgical treatment remain a challenge to the orthopaedic surgeon: some basic surgical principles apply to all of the lesions, such as cartilage debridement and shaving of necrotic tissues, while others will be used depending on the location and size of the lesions as well as the surgeon's experience. Finally, no specific technique appears to be superior to the others. Arthroscopy appears to be the most effective procedure for lesions smaller than 1 cm(2), whereas larger lesions should be filled, either with cancellous bone or with an osteochondral graft or using autogenous chondrocyte implantation. The data available in the literature should also incite orthopaedists to consider the results of surgical management with some modesty, and conservative management should remain among the therapeutic options. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  16. Galvanic corrosion behavior of titanium implants coupled to dental alloys.

    PubMed

    Cortada, M; Giner, L; Costa, S; Gil, F J; Rodríguez, D; Planell, J A

    2000-05-01

    The corrosion of five materials for implant suprastructures (cast-titanium, machined-titanium, gold alloy, silver-palladium alloy and chromium-nickel alloy), was investigated in vitro, the materials being galvanically coupled to a titanium implant. Various electrochemical parameters E(CORR), i(CORR) Evans diagrams, polarization resistance and Tafel slopes) were analyzed. The microstructure of the different dental materials was observed before and after corrosion processes by optical and electron microscopy. Besides, the metallic ions released in the saliva environment were quantified during the corrosion process by means of inductively coupled plasma-mass spectrometry technique (ICP-MS). The cast and machined titanium had the most passive current density at a given potential and chromium-nickel alloy had the most active critical current density values. The high gold content alloys have excellent resistance corrosion, although this decreases when the gold content is lower in the alloy. The palladium alloy had a low critical current density due to the presence of gallium in this composition but a selective dissolution of copper-rich phases was observed through energy dispersive X-ray analysis.

  17. Osteochondral Autograft from the Ipsilateral Femoral Head by Surgical Dislocation for Treatment of Femoral Head Fracture Dislocation: A Case Report.

    PubMed

    Won, Yougun; Lee, Gi Soo; Kim, Sang Bum; Kim, Sun Joong; Yang, Kyu Hyun

    2016-11-01

    As anatomical reduction of the articular surface of femoral head fractures and restoration of damaged cartilage are essential for good long-term results, many treatment options have been suggested, including fixation of the fracture using various surgical exposures and implants, as well as arthroscopic irrigation and debridement, bone marrow stimulating techniques, osteochondral allograft, autograft, and autogenous chondrocyte implantation. We report a case of osteochondral autograft harvested from its own femoral articular surface through surgical hip dislocation. The osteochondral graft was harvested from the inferior non-weight-bearing articular surface and grafted to the osteochondral defect. One year later, the clinical and radiological results were good, without the collapse of the femoral head or arthritic change. This procedure introduced in our case is considered convenient and able to lessen surgical time without morbidity of the donor site associated with the harvest.

  18. A new surgical technique to facilitate osteochondral autograft transfer in osteochondral defects of the capitellum: a case report.

    PubMed

    Bilsel, Kerem; Demirhan, Mehmet; Atalar, Ata Can; Akkaya, Semih

    2010-01-01

    A 17-year-old boy who was engaged in amateur weightlifting and body building presented with complaints of right elbow pain and limitation in elbow range of motion. Plain x-rays and magnetic resonance imaging showed an osteochondral defect in the medial third of the capitellum. At surgery, as a new technique, the lateral collateral ligament was detached from the humeral attachment to provide access to the capitellum with a clear and perpendicular exposure. Following removal of loose fragments within the joint, an osteochondral graft harvested from the lateral femoral condyle was implanted to the defect area of the capitellum. Postoperative radiologic controls showed that the defect was entirely filled by the graft with appropriate graft height. On follow-up examination at 12 months, the patient did not have any complaint about his elbow, and had no limitation of movement compared to the left elbow. Magnetic resonance imaging showed that the graft was successfully adapted to the recipient site without any sign of loosening. At final follow-up 40 months after surgery, the surface of the articular cartilage appeared normal. The range of elbow motion was preserved and the patient had no restriction in daily and sports activities. Considering technical difficulties posed by the narrow and complex structure of the elbow joint, this new technique involving detachment of the lateral collateral ligament facilitates perpendicular implantation of the graft. In our opinion, utilization of this new technique will improve functional and radiological results of osteochondral autograft transfer.

  19. Implantable flexible pressure measurement system based on inductive coupling.

    PubMed

    Oliveira, Cristina C; Sepúlveda, Alexandra T; Almeida, Nuno; Wardle, Brian L; da Silva, José Machado; Rocha, Luís A

    2015-02-01

    One of the currently available treatments for aortic aneurysms is endovascular aneurysm repair (EVAR). In spite of major advances in the operating techniques, complications still occur and lifelong surveillance is recommended. In order to reduce and even eliminate the commonly used surveillance imaging exams, as well as to reduce follow-up costs, new technological solutions are being pursued. In this paper, we describe the development, including design and performance characterization, of a flexible remote pressure measurement system based on inductive-coupling for post-EVAR monitoring purposes. The telemetry system architecture and operation are described and main performance characteristics discussed. The implantable sensor details are provided and its model is presented. Simulations with the reading circuit and the sensor's model were performed and compared with measurements carried out with air and a phantom as media, in order to characterize the telemetry system and validate the models. The transfer characteristic curve (pressure versus frequency) of the monitoring system was obtained with measurements performed with the sensor inside a controlled pressure vacuum chamber. Additional experimental results which proof the system functionality were obtained within a hydraulic test bench that emulates the aorta. Several innovative aspects, when compared to the state of the art, both in the sensor and in the telemetry system were achieved.

  20. First Report: Linear Incision for Placement of a Magnetically Coupled Bone-Anchored Hearing Implant.

    PubMed

    Barry, Jonnae Y; Reghunathan, Saranya; Jacob, Abraham

    2017-02-01

    Discuss use of a linear incision for placement of a magnetically coupled bone anchored hearing implant. Case series. Two patients underwent placement of magnetically coupled bone-anchored hearing implants (BAHI) through linear incisions. The first, a 40-year-old female with congenital single-sided deafness, previously had successful implantation of a percutaneous bone anchored hearing implant through a linear incision; unfortunately, she developed pain and intermittent drainage at her abutment site with time, resulting in a request for removal of her device. As an alternative to complete removal, we offered to replace the percutaneous implant with a magnetically coupled BAHI, employing the same linear incision previously. The second patient, a 53-year-old obese female with limited neck mobility and mixed hearing loss, underwent primary placement of a magnetically coupled BAHI through a linear incision. Limitations in neck mobility and patient body habitus precluded use of a traditional C-shaped incision. Both patients underwent surgery successfully, healed without incident, had their devices activated 6 weeks after their procedures, and are able to wear their implants more than 8 hours per day without discomfort. Surgical techniques for bone-anchored implants continue to evolve. Though manufacturers of magnetically coupled devices recommend using C-shaped incisions with large skin flaps, our first reported cases suggest that a small linear incision immediately overlying the implant magnet may be an acceptable alternative. Potential benefits include a smaller incision, less hair removal, smaller flap, decreased surgical time, and less postoperative pain.

  1. Porous tantalum biocomposites for osteochondral defect repair

    PubMed Central

    Mrosek, E. H.; Chung, H-W.; Fitzsimmons, J. S.; Reinholz, G. G.; Schagemann, J. C.

    2016-01-01

    Objectives We sought to determine if a durable bilayer implant composed of trabecular metal with autologous periosteum on top would be suitable to reconstitute large osteochondral defects. This design would allow for secure implant fixation, subsequent integration and remodeling. Materials and Methods Adult sheep were randomly assigned to one of three groups (n = 8/group): 1. trabecular metal/periosteal graft (TMPG), 2. trabecular metal (TM), 3. empty defect (ED). Cartilage and bone healing were assessed macroscopically, biochemically (type II collagen, sulfated glycosaminoglycan (sGAG) and double-stranded DNA (dsDNA) content) and histologically. Results At 16 weeks post-operatively, histological scores amongst treatment groups were not statistically different (TMPG: overall 12.7, cartilage 8.6, bone 4.1; TM: overall 14.2, cartilage 9.5, bone 4.9; ED: overall 13.6, cartilage 9.1, bone 4.5). Metal scaffolds were incorporated into the surrounding bone, both in TM and TMPG. The sGAG yield was lower in the neo-cartilage regions compared with the articular cartilage (AC) controls (TMPG 20.8/AC 39.5, TM 25.6/AC 33.3, ED 32.2/AC 40.2 µg sGAG/1 mg respectively), with statistical significance being achieved for the TMPG group (p < 0.05). Hypercellularity of the neo-cartilage was found in TM and ED, as the dsDNA content was significantly higher (p < 0.05) compared with contralateral AC controls (TM 126.7/AC 71.1, ED 99.3/AC 62.8 ng dsDNA/1 mg). The highest type II collagen content was found in neo-cartilage after TM compared with TMPG and ED (TM 60%/TMPG 40%/ED 39%). Inter-treatment differences were not significant. Conclusions TM is a highly suitable material for the reconstitution of osseous defects. TM enables excellent bony ingrowth and fast integration. However, combined with autologous periosteum, such a biocomposite failed to promote satisfactory neo-cartilage formation. Cite this article: E. H. Mrosek, H-W. Chung, J. S. Fitzsimmons, S. W. O’Driscoll, G. G

  2. Osteochondral tissue engineering: current strategies and challenges.

    PubMed

    Nukavarapu, Syam P; Dorcemus, Deborah L

    2013-01-01

    Osteochondral defect management and repair remain a significant challenge in orthopedic surgery. Osteochondral defects contain damage to both the articular cartilage as well as the underlying subchondral bone. In order to repair an osteochondral defect the needs of the bone, cartilage and the bone-cartilage interface must be taken into account. Current clinical treatments for the repair of osteochondral defects have only been palliative, not curative. Tissue engineering has emerged as a potential alternative as it can be effectively used to regenerate bone, cartilage and the bone-cartilage interface. Several scaffold strategies, such as single phase, layered, and recently graded structures have been developed and evaluated for osteochondral defect repair. Also, as a potential cell source, tissue specific cells and progenitor cells are widely studied in cell culture models, as well with the osteochondral scaffolds in vitro and in vivo. Novel factor strategies being developed, including single factor, multi-factor, or controlled factor release in a graded fashion, not only assist bone and cartilage regeneration, but also establish osteochondral interface formation. The field of tissue engineering has made great strides, however further research needs to be carried out to make this strategy a clinical reality. In this review, we summarize current tissue engineering strategies, including scaffold design, bioreactor use, as well as cell and factor based approaches and recent developments for osteochondral defect repair. In addition, we discuss various challenges that need to be addressed in years to come. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Biomimetic biphasic scaffolds for osteochondral defect repair

    PubMed Central

    Li, Xuezhou; Ding, Jianxun; Wang, Jincheng; Zhuang, Xiuli; Chen, Xuesi

    2015-01-01

    The osteochondral defects caused by vigorous trauma or physical disease are difficult to be managed. Tissue engineering provides a possible option to regenerate the damaged osteochondral tissues. For osteochondral reconstruction, one intact scaffold should be considered to support the regeneration of both cartilage and subchondral bone. Therefore, the biphasic scaffolds with the mimic structures of osteochondral tissues have been developed to close this chasm. A variety of biomimetic bilayer scaffolds fabricated from natural or synthetic polymers, or the ones loading with growth factors, cells, or both of them make great progresses in osteochondral defect repair. In this review, the preparation and in vitro and/or in vivo verification of bioinspired biphasic scaffolds are summarized and discussed, as well as the prospect is predicted. PMID:26816644

  4. UTE MRI of the Osteochondral Junction

    PubMed Central

    Biswas, Reni; Chen, Karen; Chang, Eric Y.; Chung, Christine B.

    2014-01-01

    The osteochondral junction is composed of numerous tissue components and serves important functions relating to structural stability and proper nutrition in joints such as the knee and spine. Conventional MR techniques have been inadequate at imaging the tissues of the osteochondral junction primarily because of the intrinsically short T2 nature of these tissues, rendering them “invisible” with the standard acquisitions. Ultrashort time to echo (UTE) MR techniques acquire sufficient MR signal of osteochondral tissues, thereby allowing direct evaluation. This article reviews the anatomy of the osteochondral junction of the knee and the spine, technical aspects of UTE MRI, and the application of UTE MRI for evaluation of the osteochondral junction. PMID:25061547

  5. Repair of osteochondral defects with in vitro engineered cartilage based on autologous bone marrow stromal cells in a swine model

    PubMed Central

    He, Aijuan; Liu, Lina; Luo, Xusong; Liu, Yu; Liu, Yi; Liu, Fangjun; Wang, Xiaoyun; Zhang, Zhiyong; Zhang, Wenjie; Liu, Wei; Cao, Yilin; Zhou, Guangdong

    2017-01-01

    Functional reconstruction of large osteochondral defects is always a major challenge in articular surgery. Some studies have reported the feasibility of repairing articular osteochondral defects using bone marrow stromal cells (BMSCs) and biodegradable scaffolds. However, no significant breakthroughs have been achieved in clinical translation due to the instability of in vivo cartilage regeneration based on direct cell-scaffold construct implantation. To overcome the disadvantages of direct cell-scaffold construct implantation, the current study proposed an in vitro cartilage regeneration strategy, providing relatively mature cartilage-like tissue with superior mechanical properties. Our strategy involved in vitro cartilage engineering, repair of osteochondral defects, and evaluation of in vivo repair efficacy. The results demonstrated that BMSC engineered cartilage in vitro (BEC-vitro) presented a time-depended maturation process. The implantation of BEC-vitro alone could successfully realize tissue-specific repair of osteochondral defects with both cartilage and subchondral bone. Furthermore, the maturity level of BEC-vitro had significant influence on the repaired results. These results indicated that in vitro cartilage regeneration using BMSCs is a promising strategy for functional reconstruction of osteochondral defect, thus promoting the clinical translation of cartilage regeneration techniques incorporating BMSCs. PMID:28084417

  6. THE ELECTROCHEMICAL PROPERTIES OF FOUR DENTAL CASTING SUPRASTRUCTURE ALLOYS COUPLED WITH TITANIUM IMPLANTS

    PubMed Central

    Tuna, Suleyman Hakan; Pekmez, Nuran Ozcícek; Keyf, Filiz; Canlí, Fulya

    2009-01-01

    Objectives: As the choice of suprastructure alloy to be combined with titanium for the oral cavity is still a much debated issue, the aim of this study was to investigate the electrochemical interaction of the suprastructure/implant couples under the determined experiment conditions. Material and Methods: The potentiodynamic polarization curves and open-circuit potentials (OCP) of four UCLA type suprastructures coupled with straight Swiss Plus implant fixtures were taken in Afnor type artificial saliva solution at 37°C. The concentration of ions leached into artificial saliva solutions was estimated with ICP-MS. SEM images of the margins of suprastructure/implant couples were obtained before and after the electrochemical tests. Results: The OCP value of titanium became passive at the most negative potential. The lowest difference between the initial and constant OCP value was exhibited by the Au based suprastructure. Suprastructures made greater contributions to the potentiodynamic polarization curves of the implant/suprastructure couples. According to the ICP-MS results, Pd based and Au based couples dissolved less than Co-Ni based and Co-Cr based couples. Conclusions: Within the conditions this study, it may be concluded that the titanium implant forms a stable passive oxide layer in artificial saliva exposed to open air and does not affect the corrosion properties of the suprastructures. Pd based and Au based couples have been found to be more corrosion-resistant than base alloy couples. PMID:19936528

  7. An analytical model for inductively coupled implantable biomedical devices with ferrite rods.

    PubMed

    Theilmann, P T; Asbeck, P M

    2009-02-01

    Using approximations applicable to near field coupled implants simplified expressions for the complex mutual inductance of coaxial aligned coils with and without a cylindrical ferrite rod are derived. Experimental results for ferrite rods of various sizes and permeabilities are presented to verify the accuracy of this expression. An equivalent circuit model for the inductive link between an implant and power coil is then presented and used to investigate how ferrite size, permeability and loss affect the power available to the implant device. Enhancements in coupling provided by high frequency, low permeability nickel zinc rods are compared with low frequency high permeability manganese zinc rods.

  8. Drilling techniques for osteochondritis dissecans.

    PubMed

    Heyworth, Benton E; Edmonds, Eric W; Murnaghan, M Lucas; Kocher, Mininder S

    2014-04-01

    Although the advanced stages of osteochondritis dissecans remain challenging to treat, most early-stage lesions in skeletally immature patients, if managed appropriately, can be stimulated to heal. For stable lesions that do not demonstrate adequate healing with nonoperative measures, such as activity modification, weight-bearing protection, or bracing, drilling of the subchondral bone has emerged as the gold standard of management. Several techniques of drilling exist, including transarticular drilling, retroarticular drilling, and notch drilling. Although each technique has been shown to be effective in small retrospective studies, higher-powered prospective comparative studies are needed to better elucidate their relative advantages and disadvantages.

  9. Biphasic nanofibrous constructs with seeded cell layers for osteochondral repair.

    PubMed

    Jin, Guang-Zhen; Kim, Jung-Ju; Park, Jeong-Hui; Seo, Seog-Jin; Kim, Joong-Hyun; Lee, Eun-Jung; Kim, Hae-Won

    2014-11-01

    Biphasic scaffolds have gained increasing attention for the regeneration of osteochondral interfacial tissue because they are expected to effectively define the interfacial structure of tissue that comprises stratified cartilage with a degree of calcification. Here, we propose a biphasic nanofiber construct made of poly(lactide-co-caprolactone) (PLCL) and its mineralized form (mPLCL) populated with cells. Primary rat articular chondrocytes (ACs) and bone marrow-derived mesenchymal stem cells (MSCs) were cultured on the layers of bare PLCL and mPLCL nanofibers, respectively, for 7 days, and the biphasic cell-nanofiber construct was investigated at 4 weeks after implantation into nude mice. Before implantation, the ACs and MSCs grown on each layer of PLCL and mPLCL nanofibers exhibited phenotypes typical of chondrocytes and osteoblasts, respectively, under proper culture conditions, as analyzed by electron microscopy, histological staining, cell growth kinetics, and real-time polymerase chain reaction. The biphasic constructs also showed the development of a possible formation of cartilage and bone tissue in vivo. Results demonstrated that the cell-laden biphasic nanofiber constructs may be useful for the repair of osteochondral interfacial tissue structure.

  10. Posterosuperior osteochondritis of the calcaneus.

    PubMed

    Cugat, Ramón; Cuscó, Xavier; García, Montserrat; Samitier, Gonzalo; Seijas, Roberto

    2007-09-01

    Osteochondritis of the posterosuperior area of the talocalcaneal surface is a relatively uncommon injury, and only 1 case has been described in the literature. We present a 37-year-old man who complained of pain in the tarsal canal area during walking and when standing up. The magnetic resonance imaging study showed an osteochondral signal in the posterosuperior medial area of the calcaneus on the talocalcaneal surface. The persistence of pain and lack of improvement with conservative treatment made arthroscopic debridement of the injury necessary. The arthroscopic procedure was performed through 2 medial portals, made under fluoroscopy, marked with needles, and dissected with mosquito clamps, and the affected surface could be fully visualized, showing a chondral lesion. Debridement of the osteonecrotic area was performed, and the Steadman technique was used on the injured bone surface. The patient was pain-free, and limited activity (i.e., standing up and walking without symptoms) was allowed. After 24 months, the patient remains asymptomatic with weight-bearing working activities and when standing. Arthroscopic curettage and scission of the injury have been shown to yield good or excellent outcomes in 75% to 80% of patients with regard to the talar surface.

  11. Viral Inactivation of Human Osteochondral Grafts with Methylene Blue and Light

    PubMed Central

    Zhao, Zhixing; Call, Gazell M.; Gao, Jizong; Yao, Jian Q.

    2014-01-01

    Objective: Cartilage injury is one of the most common disorders of synovial joints. Fresh osteochondral allografts are becoming a standard treatment; however, they are supply constrained with a potential risk of disease transmission. There are no known virucidal processes available for osteochondral allografts and most methods presently available are detrimental to cartilage. Methylene blue light treatment has been shown to be successful in the literature for viral inactivation of fresh frozen plasma. The purpose of this study was to determine the capacity of methylene blue light treatment to inactivate a panel of clinically relevant viruses inoculated onto osteochondral allografts. Design: Osteochondral grafts recovered from human cadaveric knees were inoculated with one of the following viruses: bovine viral diarrhea virus (BVDV), hepatitis A virus (HAV), human immunodeficiency virus type 1 (HIV-1), porcine parvovirus (PPV), and pseudorabies virus (PrV). The samples were processed through a methylene blue light treatment, which consisted of an initial soak in nonilluminated circulating methylene blue at ambient temperature, followed by light exposure with circulating methylene blue at cool temperatures. The final titer was compared with the recovery control for the viral log reduction. Results: HIV-1, BVDV, and PrV were reduced to nondetectable levels while HAV and PPV were reduced by 3.1 and 5.6 logs, respectively. Conclusions: The methylene blue light treatment was effective in reducing (a) enveloped DNA and RNA viruses to nondetectable levels and (b) nonenveloped DNA and RNA viruses of inoculated human osteochondral grafts by 3.1 to 5.6 logs. This study demonstrates the first practical method for significantly reducing viral load in osteochondral implants. PMID:26069682

  12. Viral Inactivation of Human Osteochondral Grafts with Methylene Blue and Light.

    PubMed

    Squillace, Donna M; Zhao, Zhixing; Call, Gazell M; Gao, Jizong; Yao, Jian Q

    2014-01-01

    Cartilage injury is one of the most common disorders of synovial joints. Fresh osteochondral allografts are becoming a standard treatment; however, they are supply constrained with a potential risk of disease transmission. There are no known virucidal processes available for osteochondral allografts and most methods presently available are detrimental to cartilage. Methylene blue light treatment has been shown to be successful in the literature for viral inactivation of fresh frozen plasma. The purpose of this study was to determine the capacity of methylene blue light treatment to inactivate a panel of clinically relevant viruses inoculated onto osteochondral allografts. Osteochondral grafts recovered from human cadaveric knees were inoculated with one of the following viruses: bovine viral diarrhea virus (BVDV), hepatitis A virus (HAV), human immunodeficiency virus type 1 (HIV-1), porcine parvovirus (PPV), and pseudorabies virus (PrV). The samples were processed through a methylene blue light treatment, which consisted of an initial soak in nonilluminated circulating methylene blue at ambient temperature, followed by light exposure with circulating methylene blue at cool temperatures. The final titer was compared with the recovery control for the viral log reduction. HIV-1, BVDV, and PrV were reduced to nondetectable levels while HAV and PPV were reduced by 3.1 and 5.6 logs, respectively. The methylene blue light treatment was effective in reducing (a) enveloped DNA and RNA viruses to nondetectable levels and (b) nonenveloped DNA and RNA viruses of inoculated human osteochondral grafts by 3.1 to 5.6 logs. This study demonstrates the first practical method for significantly reducing viral load in osteochondral implants.

  13. Stratified Scaffolds for Osteochondral Tissue Engineering.

    PubMed

    Nooeaid, Patcharakamon; Schulze-Tanzil, Gundula; Boccaccini, Aldo R

    2015-01-01

    Stratified scaffolds are promising devices finding application in the field of osteochondral tissue engineering. In this scaffold type, different biomaterials are chosen to fulfill specific features required to mimic the complex osteochondral tissue interface, including cartilage, interlayer tissue, and subchondral bone. Here, the biomaterials and fabrication methods currently used to manufacture stratified multilayered scaffolds as well as cell seeding techniques for their characterization are presented.

  14. Biomechanical evaluation of novel ultrasound-activated bioresorbable pins for the treatment of osteochondral fractures compared to established methods.

    PubMed

    Kienast, Benjamin; Mohsen, Hellal; Wendlandt, Robert; Reimers, Nils; Schulz, Arndt P; Heuer, Hinrich; Gille, Justus; Neumann, Hanjo

    2017-08-28

    Osteochondral injuries often lead to osteoarthritis of the affected joint. All established systems for refixation of osteochondral defects show certain disadvantages. To address the problem of reduced stability in resorbable implants, ultrasound-activated pins were developed. By ultrasound-activated melting of the tip of these implants, a more secure anchoring is assumed. The aim of the study was to investigate if ultrasound-activated pins can provide secure fixation of osteochondral fragments compared to screws and conventional resorbable pins. In a biomechanical laboratory setting, osteochondral fragments of the medial femoral condyle of sheep were refixated with ultrasound-activated pins [US fused poly(L-lactide-co-D,L-lactide) (PLDLLA) pins], polydioxanone (PDA) pins and conventional titanium screws. Anchoring forces of the different fixation methods were examined, registered and compared concerning shear force and tensile force. Concerning the pull out test, the US fused PLDLLA pins and titanium screws (~122 N and ~203 N) showed comparable good results, while the PDA pins showed significantly lower anchoring forces (~18 N). Examination of shear forces showed a significantly higher anchoring of the screws (~248 N) than the US fused PLDLLA pins (~218 N). Nevertheless, the US fused PLDLLA pins could significantly outperform the PDA pins (~68 N) concerning shear forces. The US fused PLDLLA pins demonstrated a comparable anchorage to the fixation with screws, but were free from the disadvantages of metal implants, i.e. the need for implant removal. The PDA pin application showed inferior biomechanical properties.

  15. Analysis of induced electrical currents from magnetic field coupling inside implantable neurostimulator leads

    PubMed Central

    2011-01-01

    Background Over the last decade, the number of neurostimulator systems implanted in patients has been rapidly growing. Nearly 50, 000 neurostimulators are implanted worldwide annually. The most common type of implantable neurostimulators is indicated for pain relief. At the same time, commercial use of other electromagnetic technologies is expanding, making electromagnetic interference (EMI) of neurostimulator function an issue of concern. Typically reported sources of neurostimulator EMI include security systems, metal detectors and wireless equipment. When near such sources, patients with implanted neurostimulators have reported adverse events such as shock, pain, and increased stimulation. In recent in vitro studies, radio frequency identification (RFID) technology has been shown to inhibit the stimulation pulse of an implantable neurostimulator system during low frequency exposure at close distances. This could potentially be due to induced electrical currents inside the implantable neurostimulator leads that are caused by magnetic field coupling from the low frequency identification system. Methods To systematically address the concerns posed by EMI, we developed a test platform to assess the interference from coupled magnetic fields on implantable neurostimulator systems. To measure interference, we recorded the output of one implantable neurostimulator, programmed for best therapy threshold settings, when in close proximity to an operating low frequency RFID emitter. The output contained electrical potentials from the neurostimulator system and those induced by EMI from the RFID emitter. We also recorded the output of the same neurostimulator system programmed for best therapy threshold settings without RFID interference. Using the Spatially Extended Nonlinear Node (SENN) model, we compared threshold factors of spinal cord fiber excitation for both recorded outputs. Results The electric current induced by low frequency RFID emitter was not significant to

  16. Dual growth factor delivery from bilayered, biodegradable hydrogel composites for spatially-guided osteochondral tissue repair

    PubMed Central

    Lu, Steven; Lam, Johnny; Trachtenberg, Jordan E.; Lee, Esther J.; Seyednejad, Hajar; van den Beucken, Jeroen J. J. P.; Tabata, Yasuhiko; Wong, Mark E.; Jansen, John A.; Mikos, Antonios G.; Kasper, F. Kurtis

    2014-01-01

    The present work investigated the use of biodegradable hydrogel composite scaffolds, based on the macromer oligo(poly(ethylene glycol) fumarate) (OPF), to deliver growth factors for the repair of osteochondral tissue in a rabbit model. In particular, bilayered OPF composites were used to mimic the structural layers of the osteochondral unit, and insulin-like growth factor-1 (IGF-1) and bone morphogenetic protein-2 (BMP-2) were loaded into gelatin microparticles and embedded within the OPF hydrogel matrix in a spatially controlled manner. Three different scaffold formations were implanted in a medial femoral condyle osteochondral defect: 1) IGF-1 in the chondral layer, 2) BMP-2 in the subchondral layer, and 3) IGF-1 and BMP-2 in their respective separate layers. The quantity and quality of osteochondral repair was evaluated at 6 and 12 weeks with histological scoring and micro-computed tomography (micro-CT). While histological scoring results at 6 weeks showed no differences between experimental groups, micro-CT analysis revealed that the delivery of BMP-2 alone increased the number of bony trabecular islets formed, an indication of early bone formation, over that of IGF-1 delivery alone. At 12 weeks post-implantation, minimal differences were detected between the three groups for cartilage repair. However, the dual delivery of IGF-1 and BMP-2 had a higher proportion of subchondral bone repair, greater bone growth at the defect margins, and lower bone specific surface than the single delivery of IGF-1. These results suggest that the delivery of BMP-2 enhances subchondral bone formation and that, while the dual delivery of IGF-1 and BMP-2 in separate layers does not improve cartilage repair under the conditions studied, they may synergistically enhance the degree of subchondral bone formation. Overall, bilayered OPF hydrogel composites demonstrate potential as spatially-guided, multiple growth factor release vehicles for osteochondral tissue repair. PMID:25047629

  17. Dual growth factor delivery from bilayered, biodegradable hydrogel composites for spatially-guided osteochondral tissue repair.

    PubMed

    Lu, Steven; Lam, Johnny; Trachtenberg, Jordan E; Lee, Esther J; Seyednejad, Hajar; van den Beucken, Jeroen J J P; Tabata, Yasuhiko; Wong, Mark E; Jansen, John A; Mikos, Antonios G; Kasper, F Kurtis

    2014-10-01

    The present work investigated the use of biodegradable hydrogel composite scaffolds, based on the macromer oligo(poly(ethylene glycol) fumarate) (OPF), to deliver growth factors for the repair of osteochondral tissue in a rabbit model. In particular, bilayered OPF composites were used to mimic the structural layers of the osteochondral unit, and insulin-like growth factor-1 (IGF-1) and bone morphogenetic protein-2 (BMP-2) were loaded into gelatin microparticles and embedded within the OPF hydrogel matrix in a spatially controlled manner. Three different scaffold formulations were implanted in a medial femoral condyle osteochondral defect: 1) IGF-1 in the chondral layer, 2) BMP-2 in the subchondral layer, and 3) IGF-1 and BMP-2 in their respective separate layers. The quantity and quality of osteochondral repair was evaluated at 6 and 12 weeks with histological scoring and micro-computed tomography (micro-CT). While histological scoring results at 6 weeks showed no differences between experimental groups, micro-CT analysis revealed that the delivery of BMP-2 alone increased the number of bony trabecular islets formed, an indication of early bone formation, over that of IGF-1 delivery alone. At 12 weeks post-implantation, minimal differences were detected between the three groups for cartilage repair. However, the dual delivery of IGF-1 and BMP-2 had a higher proportion of subchondral bone repair, greater bone growth at the defect margins, and lower bone specific surface than the single delivery of IGF-1. These results suggest that the delivery of BMP-2 enhances subchondral bone formation and that, while the dual delivery of IGF-1 and BMP-2 in separate layers does not improve cartilage repair under the conditions studied, they may synergistically enhance the degree of subchondral bone formation. Overall, bilayered OPF hydrogel composites demonstrate potential as spatially-guided, multiple growth factor release vehicles for osteochondral tissue repair.

  18. Repair Mechanism of Osteochondral Defect Promoted by Bioengineered Chondrocyte Sheet

    PubMed Central

    Kamei, Naosuke; Adachi, Nobuo; Hamanishi, Michio; Kamei, Goki; Mahmoud, Elhussein Elbadry; Nakano, Tomohiro; Iwata, Takanori; Yamato, Masayuki; Okano, Teruo; Ochi, Mitsuo

    2015-01-01

    Cell sheet engineering has developed as a remarkable method for cell transplantation. In the field of cartilage regeneration, several studies previously reported that cartilage defects could be regenerated by transplantation of a chondrocyte sheet using cell sheet engineering. However, it remains unclear how such a thin cell sheet could repair a deep cartilage defect. We, therefore, focused on the mechanism of cartilage repair using cell sheet engineering in this study. Chondrocyte sheets and synovial cell sheets were fabricated using cell sheet engineering, and these allogenic cell sheets were transplanted to cover an osteochondral defect in a rat model. Macroscopic and histological evaluation was performed at 4 and 12 weeks after transplantation. Analysis of the gene expression of each cell sheet and of the regenerated tissue at 1 week after transplantation was performed. In addition, green fluorescent protein (GFP) transgenic rats were used as donors (transplanted chondrocyte sheets) or recipients (osteochondral defect models) to identify the cell origin of regenerated cartilage. Cartilage repair was significantly better in the group implanted with a chondrocyte sheet than in that with a synovial cell sheet. The results of gene expression analysis suggest that the possible factor contributing to cartilage repair might be TGFβ1. Cell tracking experiments using GFP transgenic rats showed that the regenerated cartilage was largely composed of cells derived from the transplanted chondrocyte sheets. PMID:25396711

  19. Partial hemi-resurfacing of the hip joint--a new approach to treat local osteochondral defects?

    PubMed

    Jäger, Marcus; Begg, Malcom J W; Krauspe, Rüdiger

    2006-12-01

    There is currently renewed interest in articular resurfacing for the treatment of damaged hip-joint cartilage. In contrast to these implants, which involve endoprosthetic replacement of both articulating surfaces, we present a new joint-preserving technique that allows treatment of local osteochondral defects of the femoral head by partial hemi-resurfacing. In this study we describe the operative and technical aspects and problems for partial hemi-resurfacing of the hip joint and critically discuss indications for this procedure in one case. To guarantee an adequate view of the situs, we recommend a surgical approach involving trochanter flip osteotomy, followed by surgical dislocation of the hip joint. Besides partial hemi-resurfacing of the osteochondral defect, this approach allows treatment of associated labral tears and cartilage defects of the hip joint at the same time. For adequate implant fixation, good bone quality is required. Furthermore, osteochondral defects of limited extent and excellent patient compliance are essential for clinical success. In particular, prominence of the implant has to be avoided, which can lead to an irregular joint surface and may induce further cartilage destruction. Long-term studies on statistical populations will show if partial articular hemi-resurfacing is a bone-preserving and useful therapeutic alternative to hemi-resurfacing caps in the treatment of osteochondral hip-joint defects, especially in young patients.

  20. Magnetic resonance imaging of hyaline cartilage regeneration in neocartilage graft implantation.

    PubMed

    Tan, C F; Ng, K K; Ng, S H; Cheung, Y C

    2003-12-01

    The purpose of this study was to investigate the regenerative potential of hyaline cartilage in a neocartilage graft implant with the aid of MR cartilage imaging using a rabbit model. Surgical osteochondral defects were created in the femoral condyles of 30 mature New Zealand rabbits. The findings of neocartilage in autologous cartilage grafts packed into osteochondral defects were compared with control group of no implant to the osteochondral defect. The outcome of the implantations was correlated with histologic and MR cartilage imaging findings over a 3-month interval. Neocartilage grafts packed into osteochondral defects showed regeneration of hyaline cartilage at the outer layer of the implant using MR cartilage imaging. Fibrosis of fibrocartilage developed at the outer layer of the autologous cartilage graft together with an inflammatory reaction within the osteochondral defect. This animal study provides evidence of the regenerative ability of hyaline cartilage in neocartilage transplants to repair articular cartilage.

  1. Strategies for osteochondral repair: Focus on scaffolds

    PubMed Central

    Seo, Seog-Jin; Mahapatra, Chinmaya; Singh, Rajendra K; Knowles, Jonathan C

    2014-01-01

    Interest in osteochondral repair has been increasing with the growing number of sports-related injuries, accident traumas, and congenital diseases and disorders. Although therapeutic interventions are entering an advanced stage, current surgical procedures are still in their infancy. Unlike other tissues, the osteochondral zone shows a high level of gradient and interfacial tissue organization between bone and cartilage, and thus has unique characteristics related to the ability to resist mechanical compression and restoration. Among the possible therapies, tissue engineering of osteochondral tissues has shown considerable promise where multiple approaches of utilizing cells, scaffolds, and signaling molecules have been pursued. This review focuses particularly on the importance of scaffold design and its role in the success of osteochondral tissue engineering. Biphasic and gradient composition with proper pore configurations are the basic design consideration for scaffolds. Surface modification is an essential technique to improve the scaffold function associated with cell regulation or delivery of signaling molecules. The use of functional scaffolds with a controllable delivery strategy of multiple signaling molecules is also considered a promising therapeutic approach. In this review, we updated the recent advances in scaffolding approaches for osteochondral tissue engineering. PMID:25343021

  2. Hyaline cartilage degenerates after autologous osteochondral transplantation.

    PubMed

    Tibesku, C O; Szuwart, T; Kleffner, T O; Schlegel, P M; Jahn, U R; Van Aken, H; Fuchs, S

    2004-11-01

    Autologous osteochondral grafting is a well-established clinical procedure to treat focal cartilage defects in patients, although basic research on this topic remains sparse. The aim of the current study was to evaluate (1) histological changes of transplanted hyaline cartilage of osteochondral grafts and (2) the tissue that connects the transplanted cartilage with the adjacent cartilage in a sheep model. Both knee joints of four sheep were opened surgically and osteochondral grafts were harvested and simultaneously transplanted to the contralateral femoral condyle. The animals were sacrificed after three months and the received knee joints were evaluated histologically. Histological evaluation showed a complete ingrowth of the osseous part of the osteochondral grafts. A healing or ingrowth at the level of the cartilage could not be observed. Histological evaluation of the transplanted grafts according to Mankin revealed significantly more and more severe signs of degeneration than the adjacent cartilage, such as cloning of chondrocytes and irregularities of the articular surface. We found no connecting tissue between the transplanted and the adjacent cartilage and histological signs of degeneration of the transplanted hyaline cartilage. In the light of these findings, long-term results of autologous osteochondral grafts in human beings have to be followed critically.

  3. Mesenchymal Stem Cells for Osteochondral Tissue Engineering

    PubMed Central

    Ng, Johnathan; Bernhard, Jonathan; Vunjak-Novakovic, Gordana

    2017-01-01

    Summary Mesenchymal stem cells (MSC) are of major interest to regenerative medicine, because of the ease of harvesting from a variety of sources (including bone marrow and fat aspirates) and ability to form a range of mesenchymal tissues, in vitro and in vivo. We focus here on the use of MSCs for engineering of cartilage, bone, and complex osteochondral tissue constructs, using protocols that replicate some aspects of the natural mesodermal development. For engineering of human bone, we discuss some of the current advances, and highlight the use of perfusion bioreactors for supporting anatomically exact human bone grafts. For engineering of human cartilage, we discuss limitations of current approaches, and highlight engineering of stratified, mechanically functional human cartilage interfaced with bone by mesenchymal condensation of MSCs. Taken together, the current advances enable engineering physiologically relevant bone, cartilage and osteochondral composites, and physiologically relevant studies of osteochondral development and disease. PMID:27236665

  4. A multilayer biomaterial for osteochondral regeneration shows superiority vs microfractures for the treatment of osteochondral lesions in a multicentre randomized trial at 2 years.

    PubMed

    Kon, Elizaveta; Filardo, Giuseppe; Brittberg, Mats; Busacca, Maurizio; Condello, Vincenzo; Engebretsen, Lars; Marlovits, Stefan; Niemeyer, Philipp; Platzer, Patrik; Posthumus, Michael; Verdonk, Peter; Verdonk, Renè; Victor, Jan; van der Merwe, Willem; Widuchowski, Wojciech; Zorzi, Claudio; Marcacci, Maurilio

    2017-09-14

    study highlighted the safety and potential of a biomimetic implant. While no statistically significant differences were found compared to BMS for chondral lesions, this procedure can be considered a suitable option for the treatment of osteochondral lesions. I.

  5. Osteochondral Allografts in the Ankle Joint

    PubMed Central

    Vannini, Francesca; Buda, Roberto; Ruffilli, Alberto; Cavallo, Marco; Giannini, Sandro

    2013-01-01

    Purpose: The aim of this systematic review is to report about the clinical use of partial and total fresh osteochondral allograft in the ankle joint. The state of the art of allografts with regard to basic science, procurement and storage methods, immunogenicity, generally accepted indications and contraindications, and the rationale of the allografting procedure have been described. Methods: All studies published in PubMed from 2000 to January 2012 addressing fresh osteochondral allograft procedures in the ankle joint were identified, including those that fulfilled the following criteria: (a) level I-IV evidence addressing the areas of interest outlined above; (b) measures of functional, clinical, or imaging outcome; and (c) outcome related to ankle cartilage lesions or ankle arthritis treated by allografts. Results: The analysis showed a progressively increasing number of articles from 2000. The number of selected articles was 14; 9 of those focused on limited dimension allografts (plugs, partial) and 5 on bipolar fresh osteochondral allografts. The evaluation of evidence level showed 14 case series and no randomized studies. Conclusions: Fresh osteochondral allografts are now a versatile and suitable option for the treatment of different degrees of osteochondral disease in the ankle joint and may even be used as total joint replacement. Fresh osteochondral allografts used for total joint replacement are still experimental and might be considered as a salvage procedure in otherwise unsolvable situations. A proper selection of the patients is therefore a key point. Moreover, the patients should be adequately informed about the possible risks, benefits, and alternatives to the allograft procedure. PMID:26069666

  6. Subchondral pre-solidified chitosan/blood implants elicit reproducible early osteochondral wound-repair responses including neutrophil and stromal cell chemotaxis, bone resorption and repair, enhanced repair tissue integration and delayed matrix deposition

    PubMed Central

    2013-01-01

    Background In this study we evaluated a novel approach to guide the bone marrow-driven articular cartilage repair response in skeletally aged rabbits. We hypothesized that dispersed chitosan particles implanted close to the bone marrow degrade in situ in a molecular mass-dependent manner, and attract more stromal cells to the site in aged rabbits compared to the blood clot in untreated controls. Methods Three microdrill hole defects, 1.4 mm diameter and 2 mm deep, were created in both knee trochlea of 30 month-old New Zealand White rabbits. Each of 3 isotonic chitosan solutions (150, 40, 10 kDa, 80% degree of deaceylation, with fluorescent chitosan tracer) was mixed with autologous rabbit whole blood, clotted with Tissue Factor to form cylindrical implants, and press-fit in drill holes in the left knee while contralateral holes received Tissue Factor or no treatment. At day 1 or day 21 post-operative, defects were analyzed by micro-computed tomography, histomorphometry and stereology for bone and soft tissue repair. Results All 3 implants filled the top of defects at day 1 and were partly degraded in situ at 21 days post-operative. All implants attracted neutrophils, osteoclasts and abundant bone marrow-derived stromal cells, stimulated bone resorption followed by new woven bone repair (bone remodeling) and promoted repair tissue-bone integration. 150 kDa chitosan implant was less degraded, and elicited more apoptotic neutrophils and bone resorption than 10 kDa chitosan implant. Drilled controls elicited a poorly integrated fibrous or fibrocartilaginous tissue. Conclusions Pre-solidified implants elicit stromal cells and vigorous bone plate remodeling through a phase involving neutrophil chemotaxis. Pre-solidified chitosan implants are tunable by molecular mass, and could be beneficial for augmented marrow stimulation therapy if the recruited stromal cells can progress to bone and cartilage repair. PMID:23324433

  7. Fresh-Stored Osteochondral Allograft for Treatment of Osteochondritis Dissecans the Femoral Head

    DTIC Science & Technology

    2010-01-01

    longevity and sur- vivorship [7, 30, 31]. A rotational osteotomy is another viable option because it is a joint-preserving procedure and delays the need...Osteochondral defects of the femoral head are exceedingly rare, with limited treatment options. Restora- tion procedures for similar defects involving the...develop secondary to trauma and underwent subsequent treatment using a fresh-stored osteochondral allograft via a trochanteric osteotomy . At the 1-year

  8. Osteochondral repair in hemophilic ankle arthropathy: from current options to future perspectives.

    PubMed

    Buda, Roberto; Cavallo, Marco; Castagnini, Francesco; Ferranti, Enrico; Natali, Simone; Giannini, Sandro

    2015-01-01

    Young hemophilic patients are frequently affected by ankle arthropathy. At the end stage of the disease, the current treatments are arthrodesis and arthroplasty, which have significant drawbacks. Validated procedures capable of slowing down or even arresting the progression towards the end stage are currently lacking. This review aims to discuss the rationale for and feasibility of applying, in mild hemophilic ankle arthropathy, the main techniques currently used to treat osteochondral defects, focusing in particular on ankle distraction, chondrocyte implantation, mesenchymal stem cell transplantation, allograft transplantation and the use of growth factors. To date, ankle distraction is the only procedure that has been successfully used in hemophilic ankle arthropathy. The use of mesenchymal stem cells have recently been evaluated as feasible for osteochondral repair in hemophilic patients. There may be a rationale for the use of growth factors if they are combined with the previous techniques, which could be useful to arrest the progression of the degeneration or delay end-stage procedures.

  9. Genetics Home Reference: familial osteochondritis dissecans

    MedlinePlus

    ... Familial osteochondritis dissecans Seattle Children's TeensHealth from Nemours: Knee Injuries University of Connecticut Health Center Patient Support and Advocacy Resources (1 link) American College of Rheumatology: Osteoarthritis ClinicalTrials.gov (1 link) ClinicalTrials.gov Scientific Articles ...

  10. Coupling of a locally implanted rare-earth ion ensemble to a superconducting micro-resonator

    SciTech Connect

    Wisby, I. Tzalenchuk, A. Ya.; Graaf, S. E. de; Adamyan, A.; Kubatkin, S. E.; Gwilliam, R.; Meeson, P. J.; Lindström, T.

    2014-09-08

    We demonstrate the coupling of rare-earth ions locally implanted in a substrate (Gd{sup 3+} in Al{sub 2}O{sub 3}) to a superconducting NbN lumped-element micro-resonator. The hybrid device is fabricated by a controlled ion implantation of rare-earth ions in well-defined micron-sized areas, aligned to lithographically defined micro-resonators. The technique does not degrade the internal quality factor of the resonators which remain above 10{sup 5}. Using microwave absorption spectroscopy, we observe electron-spin resonances in good agreement with numerical modelling and extract corresponding coupling rates of the order of 1 MHz and spin linewidths of 50–65 MHz.

  11. S53P4 bioactive glass and fibrin glue for the treatment of osteochondral lesions of the knee - a preliminary in vivo study in rabbits.

    PubMed

    Zazgyva, AncuŢa Marilena; Gurzu, Simona; Jung, Ioan; Nagy, Örs; Mühlfay, Gheorghe; Pop, Tudor Sorin

    2015-01-01

    The role of the subchondral bone and the importance of treating both bone and cartilage in cases of chondral and osteochondral lesions of the knee have been highly emphasized. There are no current studies on the experimental use of bioactive glass S53P4 (BonAlive®) as granules in the treatment of osteochondral lesions of the knee. Our preliminary study was designed to establish an experimental model and assesses the effect of glass granules fixed with fibrin compared to fibrin alone as fillers of the osteochondral defects created in the weight-bearing and partial weight-bearing regions of the distal femur in six adult rabbits. We found that the size of the distal femur in adult domestic rabbits allows the creation of 4 mm diameter and 5 mm deep osteochondral defects on both the medial femoral condyle and the trochlea, bilaterally, without significantly affecting the activity level of the animals. Retention of the glass granules in the defects was achieved successfully using a commercially available fibrin sealant. At five weeks post-implantation, we found macroscopic and microscopic differences between the four types of defects. The use of bioactive glass S53P4 for filling condylar osteochondral defects in rabbit femora led to the initiation of an early bone repair process, observed at five weeks after implantation, while the filling of trochlear defects with fibrin glue resulted in the appearance of cartilaginous tissue characteristic of endochondral ossification.

  12. Evaluation and analysis of graft hypertrophy by means of arthroscopy, biochemical MRI and osteochondral biopsies in a patient following autologous chondrocyte implantation for treatment of a full-thickness-cartilage defect of the knee.

    PubMed

    Niemeyer, Philipp; Uhl, Markus; Salzmann, Gian M; Morscheid, Yannik P; Südkamp, Norbert P; Madry, Henning

    2015-06-01

    Graft hypertrophy represents a characteristic complication following autologous chondrocyte implantation (ACI) for treatment of cartilage defects. Although some epidemiological data suggest that incidence is associated with first-generation ACI using autologous chondrocyte implantation, it has also been reported in other technical modifications of ACI using different biomaterials. Nevertheless, it has not been described in autologous, non-periosteum, implant-free associated ACI. In addition, little is known about histological and T2-relaxation appearance of graft hypertrophy. The present case report provides a rare case of extensive graft hypertrophy following ACI using an autologous spheres technique with clinical progression over time. Detailed clinical, MR tomographic and histological evaluation has been performed, which demonstrates a high quality of repair tissue within the hypertrophic as well as non-hypertrophic transplanted areas of the repair tissue. No expression of collagen type X (a sign of chondrocyte hypertrophy), only slight changes of the subchondral bone and a nearly normal cell-matrix ratio suggest that tissue within the hypertrophic area does not significantly differ from intact and high-quality repair tissue and therefore seems not to cause graft hypertrophy. This is in contrast to the assumption that histological hypertrophy might cause or contribute to an overwhelming growth of the repair tissue within the transplantation site. Data presented in this manuscript might contribute to further explain the etiology of graft hypertrophy following ACI.

  13. Osteochondral grafting for cartilage defects in the patellar grooves of bilateral knee joints.

    PubMed

    Nakagawa, Yasuaki; Matsusue, Yoshitaka; Suzuki, Takashi; Kuroki, Hiroshi; Nakamura, Takashi

    2004-07-01

    Autogenous osteochondral grafts have become popular recently for use in small, isolated, contained articular cartilage defects. We treated a 35-year-old man who had cartilage defects, which were the same shape and probably the result of overuse, in the patellar grooves of both knee joints. The left side was 30 x 25 mm, and the right side was 17 x 17 mm in his right patellar groove, and 15 x 7 mm in his right medial femoral condyle. Therefore, we performed multiple osteochondral grafting of the bilateral lesions. Thirty-two months after his right knee operation (37 months after his left one), he had no pain or symptoms in his left knee and occasional mild pain and catching in his right knee. At second-look arthroscopy, the joint surface of the articular cartilage in the bilateral patellar groove was almost completely smooth. However, the whole of the weight-bearing area around the grafted plugs in the medial femoral condyle showed cartilage degeneration. Approximately 3 years after implantation of osteochondral grafts into similarly shaped cartilage lesions in the bilateral patellar grooves, the operative results were good. However, careful follow up is needed.

  14. Chitosan-Based Bilayer Hydroxyapatite Nanorod Composite Scaffolds for Osteochondral Regeneration

    NASA Astrophysics Data System (ADS)

    Swanson, Shawn

    Osteochondral defects involve injury to bone and cartilage. As articular cartilage is worn down, bone in the joint begins to rub together, causing bone spurs. This is known as osteoarthritis, and is a common issue among the aging population. This problem presents an interesting opportunity for tissue engineering. Tissue engineering is an approach to treatment of tissue defects where synthetic, three dimensional (3-D) scaffolds are implanted in a defect to facilitate healing. The osteochondral scaffold consists of two regions in the form of a bilayer scaffold- one to mimic bone with osteoconductive properties, and one to mimic cartilage with biomimetic properties. One approach to improving the osteoconductivity of tissue engineering scaffolds is the addition of hydroxyapatite (HAp), the main mineral phase in bone. HAp with nanorod morphology is desirable because it is biomimetic for the calcium phosphate found in bone. Incorporating HAp nanorods in bone tissue engineering scaffolds to form a composite material may increase scaffold osteoconductivity. The cartilage scaffold is fabricated from chitosan and hyaluronic acid (HA). HA is a known component of cartilage and thus is biomimetic. The bilayer scaffolds were seeded with osteoblast-like MG-63 cells to investigate cell migration and were evaluated with Alamar Blue proliferation assay. The cells successfully migrated to the bone region of the scaffold, indicating that the bilayer scaffold provides a promising osteochondral scaffold.

  15. Osteochondral defects in the ankle: why painful?

    PubMed Central

    Reilingh, Mikel L.; Zengerink, Maartje; van Bergen, Christiaan J. A.

    2010-01-01

    Osteochondral defects of the ankle can either heal and remain asymptomatic or progress to deep ankle pain on weight bearing and formation of subchondral bone cysts. The development of a symptomatic OD depends on various factors, including the damage and insufficient repair of the subchondral bone plate. The ankle joint has a high congruency. During loading, compressed cartilage forces its water into the microfractured subchondral bone, leading to a localized high increased flow and pressure of fluid in the subchondral bone. This will result in local osteolysis and can explain the slow development of a subchondral cyst. The pain does not arise from the cartilage lesion, but is most probably caused by repetitive high fluid pressure during walking, which results in stimulation of the highly innervated subchondral bone underneath the cartilage defect. Understanding the natural history of osteochondral defects could lead to the development of strategies for preventing progressive joint damage. PMID:20151110

  16. Osteochondritis of the Distal Tibial Epiphysis

    PubMed Central

    EL Hajj, Firass; Sebaaly, Amer; Kharrat, Khalil; Ghanem, Ismat

    2012-01-01

    Osteochondritis of the distal tibial epiphysis is a very rare entity. 9 cases have been described in 7 articles and 8 other cases have been mentioned in textbooks. This paper describes the 10th case of osteochondritis of the distal tibial epiphysis and summarizes the clinical and radiological presentations of the 9 other cases. The etiology of this entity is well debated in the literature. We believe that it results from a vascular abnormality in the distal tibial epiphysis associated with a mechanical stress (trauma, excessive overload, etc.). Since it is a self-limited disease, the prognosis is good and the younger the patient is the better the prognosis will be. In general, this entity responds well to conservative treatment. PMID:23193412

  17. Osteochondral defects in the ankle: why painful?

    PubMed

    van Dijk, C Niek; Reilingh, Mikel L; Zengerink, Maartje; van Bergen, Christiaan J A

    2010-05-01

    Osteochondral defects of the ankle can either heal and remain asymptomatic or progress to deep ankle pain on weight bearing and formation of subchondral bone cysts. The development of a symptomatic OD depends on various factors, including the damage and insufficient repair of the subchondral bone plate. The ankle joint has a high congruency. During loading, compressed cartilage forces its water into the microfractured subchondral bone, leading to a localized high increased flow and pressure of fluid in the subchondral bone. This will result in local osteolysis and can explain the slow development of a subchondral cyst. The pain does not arise from the cartilage lesion, but is most probably caused by repetitive high fluid pressure during walking, which results in stimulation of the highly innervated subchondral bone underneath the cartilage defect. Understanding the natural history of osteochondral defects could lead to the development of strategies for preventing progressive joint damage.

  18. Rabbit trochlear model of osteochondral allograft transplantation.

    PubMed

    To, Nhat; Curtiss, Shane; Neu, Corey P; Salgado, Christopher J; Jamali, Amir A

    2011-10-01

    Allografting and autografting of osteochondral tissues is a promising strategy to treat articular cartilage lesions in damaged joints. We developed a new model of fresh osteochondral allografting using the entire rabbit trochlea. The objective of the current study was to demonstrate that this model would achieve reproducible graft-host healing and maintain normal articular cartilage histologic, immunolocalization, and biochemical characteristics after transplantation under diverse storage and transplantation conditions. New Zealand white (n = 8) and Dutch belted (n = 8) rabbits underwent a 2-stage transplantation operation using osteochondral grafts that had been stored for 2 or 4 wk. Trochlear grafts harvested from the left knee were transplanted to the right knee as either autografts or allografts. Grafts were fixed with 22-gauge steel wire or 3-0 nylon suture. Rabbits were euthanized for evaluation at 1, 2, 4, 6, and 12 wk after transplantation. All grafts that remained in vivo for at least 4 wk demonstrated 100% interface healing by microCT. Trabecular bridging was present at the host-graft interface starting at 2 wk after transplantation, with no significant difference in cartilage histology between the various groups. The combined histology scores indicated minimal evidence of osteoarthritis. Immunostaining revealed that superficial zone protein was localized at the surface of all transplants. The rabbit trochlear model met our criteria for a successful model in regard to the ease of the procedure, low rate of surgical complications, relatively large articular cartilage surface area, and amount of host-graft bone interface available for analysis.

  19. Repair of porcine articular cartilage defect with a biphasic osteochondral composite.

    PubMed

    Jiang, Ching-Chuan; Chiang, Hongsen; Liao, Chun-Jen; Lin, Yu-Ju; Kuo, Tzong-Fu; Shieh, Chang-Shun; Huang, Yi-You; Tuan, Rocky S

    2007-10-01

    Autologous chondrocyte implantation (ACI) has been recently used to treat cartilage defects. Partly because of the success of mosaicplasty, a procedure that involves the implantation of native osteochondral plugs, it is of potential significance to consider the application of ACI in the form of biphasic osteochondral composites. To test the clinical applicability of such composite construct, we repaired osteochondral defect with ACI at low cell-seeding density on a biphasic scaffold, and combined graft harvest and implantation in a single surgery. We fabricated a biphasic cylindrical porous plug of DL-poly-lactide-co-glycolide, with its lower body impregnated with beta-tricalcium phosphate as the osseous phase. Osteochondral defects were surgically created at the weight-bearing surface of femoral condyles of Lee-Sung mini-pigs. Autologous chondrocytes isolated from the cartilage were seeded into the upper, chondral phase of the plug, which was inserted by press-fitting to fill the defect. Defects treated with cell-free plugs served as control. Outcome of repair was examined 6 months after surgery. In the osseous phase, the biomaterial retained in the center and cancellous bone formed in the periphery, integrating well with native subchondral bone with extensive remodeling, as depicted on X-ray roentgenography by higher radiolucency. In the chondral phase, collagen type II immunohistochemistry and Safranin O histological staining showed hyaline cartilage regeneration in the experimental group, whereas only fibrous tissue formed in the control group. On the International Cartilage Repair Society Scale, the experimental group had higher mean scores in surface, matrix, cell distribution, and cell viability than control, but was comparable with the control group in subchondral bone and mineralization. Tensile stress-relaxation behavior determined by uni-axial indentation test revealed similar creep property between the surface of the experimental specimen and native

  20. Humeral Head Reconstruction With Osteochondral Allograft Transplantation.

    PubMed

    Saltzman, Bryan M; Riboh, Jonathan C; Cole, Brian J; Yanke, Adam B

    2015-09-01

    To synthesize, in a systematic review, the available clinical evidence of osteochondral allograft transplants for large osteochondral defects of the humeral head. The Medline, Embase, and Cochrane databases were searched for studies reporting clinical or radiographic outcomes of osteochondral allograft transplantation for humeral head defects. Descriptive statistics were provided for all outcomes. After checking for data normality, we compared postoperative and preoperative values using the Student t test. We included 12 studies (8 case reports and 4 case series) in this review. The study group consisted of 35 patients. The mean age was 35.4 ± 18.1 years; 77% of patients were male patients. Thirty-three patients had large Hill-Sachs lesions due to instability, 1 had an osteochondritis dissecans lesion, and 1 had an iatrogenic lesion after resection of synovial chondromatosis. The mean lesion size was 3 ± 1.4 cm (anteroposterior) by 2.25 ± 0.3 cm (medial-lateral), representing on average 40.5% ± 4.73% of the native articular surface. Of the 35 patients, 3 received a fresh graft, with all others receiving frozen grafts. Twenty-three femoral heads, 10 humeral heads, and 2 sets of osteochondral plugs were used. The mean length of follow-up was 57 months. Significant improvements were seen in forward flexion at 6 months (68° ± 18.1°, P < .001), forward flexion at 12 months (83.42° ± 18.3°, P < .001), and external rotation at 12 months (38.72° ± 18.8°, P < .001). American Shoulder and Elbow Surgeons scores improved by 14 points (P = .02). Radiographic studies at final follow-up showed allograft necrosis in 8.7% of cases, resorption in 36.2%, and glenohumeral arthritic changes in 35.7%. Complication rates were between 20% and 30%, and the reoperation rate was 26.67%. Although only 3 patients received fresh allografts, there were no reports of graft resorption, necrosis, or arthritic changes in these patients. Humeral head allograft-most commonly used in the

  1. Recent progress in interfacial tissue engineering approaches for osteochondral defects.

    PubMed

    Castro, Nathan J; Hacking, S Adam; Zhang, Lijie Grace

    2012-08-01

    This review provides a brief synopsis of the anatomy and physiology of the osteochondral interface, scaffold-based and non-scaffold based approaches for engineering both tissues independently as well as recent developments in the manufacture of gradient constructs. Novel manufacturing techniques and nanotechnology will be discussed with potential application in osteochondral interfacial tissue engineering.

  2. The effects of the coupling of titanium implants and dissimilar metal abutments on osteoblast differentiation in vitro.

    PubMed

    Taylor, J C; Anderson, G I; Sutow, E J; Driscoll, C F; Mackey, D C

    1999-01-01

    This study evaluated the effect of titanium endosseous dental implants coupled to dissimilar materials on the capacity of preosteoblasts in bone marrow culture to differentiate, to form alkaline phosphatase-positive colonies, and to mineralize. Ten UCLA abutments were cast in each of 4 alloys: Type III gold, ceramometal gold, commercially pure grade I titanium, and titanium-aluminum-vanadium (Ti-6Al-4V); 10 ceramic abutments and 30 sterile Brånemark System implants were also used. Five abutments of each material and 5 implants were incubated individually in rat bone marrow culture, as were 5 of each abutment attached to an implant; bone marrow cultures not containing test samples were used as controls. Following 17 days of culture, the solution potentials of individual abutments (except ceramic), the implant, and the implant-abutment couples were measured in the test medium. One dish of each group of 5 was then stained for bone nodule mineralization; the remainder were quantified by area for alkaline phosphatase staining. Statistical analysis of measured in vitro potentials showed that the uncoupled samples formed 2 groups, and coupled samples formed 3 groups. Analysis of variance for alkaline phosphatase-positive area values showed no significant differences between coupled or uncoupled groups and the control. Normal cell differentiation and morphology as well as a lack of zones of inhibition, were observed. Bone nodule mineralization was evident in all groups. It was concluded that the presence of these commonly used implant abutment biomaterials coupled to titanium endosseous dental implants had no adverse effects on the in vitro capacity of preosteoblasts in marrow to differentiate and to form mineralized bone nodules, despite measured differences in solution potentials.

  3. Dysplasia Epiphysealis Hemimelica Treated with Osteochondral Allograft: A Case Report

    PubMed Central

    Anthony, Chris A.; Wolf, Brian R.

    2015-01-01

    Background Dysplasia epiphysealis hemimelica (DEH), or Trevor's disease, is a developmental disorder of the pediatric skeleton characterized by asymmetric osteochondral overgrowth. Methods We present the case of a five year old boy with a two year history of right knee pain and evidence of DEH on imaging who underwent initial arthroscopic resection of his lesion with subsequent recurrence. The patient then underwent osteochondral allograft revision surgery and was asymptomatic at two year follow-up with a congruent joint surface. Results To our knowledge, this is the first reported case of a DEH lesion treated with osteochondral allograft and also the youngest reported case of osteochondral allograft placement in the literature. Conclusions Osteochondral allograft may be a viable option in DEH and other deformities of the pediatric knee. Level of Evidence Level V PMID:26361443

  4. [Ossicular coupling of an implantable hearing aid transducer using an Er:YAG laser].

    PubMed

    Lehner, R L; Maassen, M M; Plester, D; Zenner, H P

    1997-10-01

    Special coupling devices made of pure gold or titanium have been developed to connect a new implantable hearing aid transducer (Tübingen implant) to the ossicular chain. They allow piezotransducer probe-tip connection to the long process of the incus or the stapedial head. Similar to the design of conventional PORPs (partial ossicular replacement prostheses), the coupling devices can be fixed at the ossicular chain, e.g., with the eye loop of stapedial piston prostheses or the bell element of golden wire PORPs. A crimp technique allows connection between coupling device and transducer probe tip [5]. The main disadvantage in connecting the long process of the incus or the stapes having is to drill a dorsal tympanotomy in the posterior wall of the ear canal during surgery. The short distance between tympanotomy and N. facialis contains serious surgical risks. To avoid the risk of facial paralysis, Fredrickson's alternative coupling technique for the body of the incus is investigated in this paper [2]. In this case, the transducer probe tip will be positioned to the incus body and placed on its surface with controlled elastic displacement of the ossicular chain. The simple direct attachment of the probe-tip end on the surface of the incus, however, will not guarantee a stable long-term connection. Thus, by creating a conical, 0.5-to 0.7-mm-deep hole in the incus, the probe tip will be fitted much better. With a novel surgical Erbium-YAG laser this can be done in a contactless procedure. In this paper, first results of microsurgical laser applications with human temporal bones will be shown.

  5. Cylindrical Costal Osteochondral Autograft for Reconstruction of Large Defects of the Capitellum Due to Osteochondritis Dissecans

    PubMed Central

    Shimada, Kozo; Tanaka, Hiroyuki; Matsumoto, Taiichi; Miyake, Junichi; Higuchi, Haruhisa; Gamo, Kazushige; Fuji, Takeshi

    2012-01-01

    Background: There is a need to clarify the usefulness of and problems associated with cylindrical costal osteochondral autograft for reconstruction of large defects of the capitellum due to osteochondritis dissecans. Methods: Twenty-six patients with advanced osteochondritis dissecans of the humeral capitellum were treated with use of cylindrical costal osteochondral autograft. All were males with elbow pain and full-thickness articular cartilage lesions of ≥15 mm in diameter. Clinical, radiographic, and magnetic resonance imaging outcomes were evaluated at a mean follow-up of thirty-six months (range, twenty-four to fifty-one months). Results: All patients had rapid functional improvement after treatment with costal osteochondral autograft and returned to their former activities, including sports. Five patients needed additional minor surgical procedures, including screw removal, loose body removal, and shaving of protruded articular cartilage. Mean elbow function, assessed with use of the clinical rating system of Timmerman and Andrews, was 111 points preoperatively and improved to 180 points at the time of follow-up and to 190 points after the five patients underwent the additional operations. Mean elbow motion was 126° of flexion with 16° of extension loss preoperatively and improved to 133° of flexion with 3° of extension loss at the time of follow-up. Osseous union of the graft on radiographs was obtained within three months in all patients. Revascularization of the graft depicted on T1-weighted magnetic resonance imaging and congruity of the reconstructed articular surface depicted on T2-weighted or short tau inversion recovery imaging were assessed at twelve and twenty-four months postoperatively. Functional recovery was good, and all patients were satisfied with the final outcomes. Conclusions: Cylindrical costal osteochondral autograft was useful for the treatment of advanced osteochondritis dissecans of the humeral capitellum. Functional recovery

  6. Cartilage repair: A review of Stanmore experience in the treatment of osteochondral defects in the knee with various surgical techniques.

    PubMed

    Vijayan, S; Bentley, G; Briggs, Twr; Skinner, Ja; Carrington, Rwj; Pollock, R; Flanagan, Am

    2010-07-01

    Articular cartilage damage in the young adult knee, if left untreated, it may proceed to degenerative osteoarthritis and is a serious cause of disability and loss of function. Surgical cartilage repair of an osteochondral defect can give the patient significant relief from symptoms and preserve the functional life of the joint. Several techniques including bone marrow stimulation, cartilage tissue based therapy, cartilage cell seeded therapies and osteotomies have been described in the literature with varying results. Established techniques rely mainly on the formation of fibro-cartilage, which has been shown to degenerate over time due to shear forces. The implantation of autologous cultured chondrocytes into an osteochondral defect, may replace damaged cartilage with hyaline or hyaline-like cartilage. This clinical review assesses current surgical techniques and makes recommendations on the most appropriate method of cartilage repair when managing symptomatic osteochondral defects of the knee. We also discuss the experience with the technique of autologous chondrocyte implantation at our institution over the past 11 years.

  7. Cartilage repair: A review of Stanmore experience in the treatment of osteochondral defects in the knee with various surgical techniques

    PubMed Central

    Vijayan, S; Bentley, G; Briggs, TWR; Skinner, JA; Carrington, RWJ; Pollock, R; Flanagan, AM

    2010-01-01

    Articular cartilage damage in the young adult knee, if left untreated, it may proceed to degenerative osteoarthritis and is a serious cause of disability and loss of function. Surgical cartilage repair of an osteochondral defect can give the patient significant relief from symptoms and preserve the functional life of the joint. Several techniques including bone marrow stimulation, cartilage tissue based therapy, cartilage cell seeded therapies and osteotomies have been described in the literature with varying results. Established techniques rely mainly on the formation of fibro-cartilage, which has been shown to degenerate over time due to shear forces. The implantation of autologous cultured chondrocytes into an osteochondral defect, may replace damaged cartilage with hyaline or hyaline-like cartilage. This clinical review assesses current surgical techniques and makes recommendations on the most appropriate method of cartilage repair when managing symptomatic osteochondral defects of the knee. We also discuss the experience with the technique of autologous chondrocyte implantation at our institution over the past 11 years. PMID:20697474

  8. 3D Bioprinting for Cartilage and Osteochondral Tissue Engineering.

    PubMed

    Daly, Andrew C; Freeman, Fiona E; Gonzalez-Fernandez, Tomas; Critchley, Susan E; Nulty, Jessica; Kelly, Daniel J

    2017-08-14

    Significant progress has been made in the field of cartilage and bone tissue engineering over the last two decades. As a result, there is real promise that strategies to regenerate rather than replace damaged or diseased bones and joints will one day reach the clinic however, a number of major challenges must still be addressed before this becomes a reality. These include vascularization in the context of large bone defect repair, engineering complex gradients for bone-soft tissue interface regeneration and recapitulating the stratified zonal architecture present in many adult tissues such as articular cartilage. Tissue engineered constructs typically lack such spatial complexity in cell types and tissue organization, which may explain their relatively limited success to date. This has led to increased interest in bioprinting technologies in the field of musculoskeletal tissue engineering. The additive, layer by layer nature of such biofabrication strategies makes it possible to generate zonal distributions of cells, matrix and bioactive cues in 3D. The adoption of biofabrication technology in musculoskeletal tissue engineering may therefore make it possible to produce the next generation of biological implants capable of treating a range of conditions. Here, advances in bioprinting for cartilage and osteochondral tissue engineering are reviewed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Fertility goal-based counseling increases contraceptive implant and IUD use in HIV discordant couples in Rwanda and Zambia

    PubMed Central

    KHU, Naw H.; VWALIKA, Bellington; KARITA, Etienne; KILEMBE, William; BAYINGANA, Roger A.; SITRIN, Deborah; ROEBER-RICE, Heidi; LEARNER, Emily; TICHACEK, Amanda C.; HADDAD, Lisa B.; WALL, Kristin M.; CHOMBA, Elwyn N.; ALLEN, Susan A.

    2012-01-01

    Background HIV discordant heterosexual couples are faced with the dual challenge of preventing sexual HIV transmission and unplanned pregnancies with the attendant risk of perinatal HIV transmission. Our aim was to examine uptake of two long-acting reversible contraceptive (LARC) methods – intrauterine devices (IUDs) and hormonal implants – among HIV discordant couples in Rwanda and Zambia. Study Design Women were interviewed alone or with their partner during routine cohort study follow-up visits to ascertain fertility goals; those not pregnant, not infertile, not already using LARC, and wishing to limit or delay fertility for ≥3 years were counseled on LARC methods and offered an IUD and implant on-site. Results Among 409 fertile Rwandan women interviewed (126 alone, 283 with partners), 365 (89%) were counseled about LARC methods and 130 (36%) adopted a method (100 implant, 30 IUD). Of 787 fertile Zambian women interviewed (457 alone, 330 with partners), 528 (67%) received LARC counseling, of whom 177 (34%) adopted a method (139 implant, 38 IUD). In both countries, a woman’s younger age was predictive of LARC uptake. LARC users reported fewer episodes of unprotected sex than couples using only condoms. Conclusions Integrated fertility-goal based family planning counseling and access to LARC methods with reinforcement of dual-method use prompted uptake of IUDs and implants and reduced unprotected sex among HIV-discordant couples in two African capital cities. PMID:23153896

  10. Emerging genetic basis of osteochondritis dissecans.

    PubMed

    Bates, J Tyler; Jacobs, John C; Shea, Kevin G; Oxford, Julia Thom

    2014-04-01

    Genome-wide association studies (GWAS) provide an unbiased approach in the identification of genes that increase the risk for osteochondritis dissecans (OCD). Recent GWAS in humans, horses, and pigs are reviewed and genes identified. The identified genes tended to cluster with respect to function and biologic processes. GWAS in humans are a critical next step in the effort to provide a better understanding of the causes of OCD, which will, in turn, allow preventive strategies for treatment of adolescents and young adults who are at risk for the development of degenerative joint disease due to the effects of OCD.

  11. Cartilage repair and subchondral bone migration using 3D printing osteochondral composites: a one-year-period study in rabbit trochlea.

    PubMed

    Zhang, Weijie; Lian, Qin; Li, Dichen; Wang, Kunzheng; Hao, Dingjun; Bian, Weiguo; He, Jiankang; Jin, Zhongmin

    2014-01-01

    Increasing evidences show that subchondral bone may play a significant role in the repair or progression of cartilage damage in situ. However, the exact change of subchondral bone during osteochondral repair is still poorly understood. In this paper, biphasic osteochondral composite scaffolds were fabricated by 3D printing technology using PEG hydrogel and β-TCP ceramic and then implanted in rabbit trochlea within a critical size defect model. Animals were euthanized at 1, 2, 4, 8, 16, 24, and 52 weeks after implantation. Histological results showed that hyaline-like cartilage formed along with white smooth surface and invisible margin at 24 weeks postoperatively, typical tidemark formation at 52 weeks. The repaired subchondral bone formed from 16 to 52 weeks in a "flow like" manner from surrounding bone to the defect center gradually. Statistical analysis illustrated that both subchondral bone volume and migration area percentage were highly correlated with the gross appearance Wayne score of repaired cartilage. Therefore, subchondral bone migration is related to cartilage repair for critical size osteochondral defects. Furthermore, the subchondral bone remodeling proceeds in a "flow like" manner and repaired cartilage with tidemark implies that the biphasic PEG/β-TCP composites fabricated by 3D printing provides a feasible strategy for osteochondral tissue engineering application.

  12. Biodegradable poly-L-lactide-co-glycolide copolymer pin fixation of a traumatic patellar osteochondral fragment in an 11-year-old child: A novel surgical approach

    PubMed Central

    Sinikumpu, Juha-Jaakko; Serlo, Willy

    2017-01-01

    Treating displaced patellar bone fractures in growing children remains a challenge for orthopedic surgeons. Removal of loose bone fragments may prolong healing time and result in early onset osteoarthrosis. Therefore, primary fixation of osteochondral fragments is preferred. Metallic pin and screw implants are typically used for fixation, as there is little evidence available regarding the use of modern biodegradable implants in traumatic patellar fractures of a premature skeleton. The present report describes a novel operative technique using headless poly-L-lactide-co-glycolide (PLGA) pins in treating an 11-year-old girl with a patellar fracture from a cycling injury. The surgical technique of this procedure is described in detail in the current report. Excellent subjective outcomes were achieved from this surgery, with superb bone healing according to follow-up radiographic and computerized tomography scans. In conclusion, the results of this case indicate that, similarly to osteochondritis, intra-articular osteochondral fractures in children may be fixed using biodegradable PLGA pins. Randomized clinical trials should be performed to confirm this finding and evaluate the use of PLGA pins as a treatment for adolescent osteochondral fractures. PMID:28123496

  13. Cartilage Repair and Subchondral Bone Migration Using 3D Printing Osteochondral Composites: A One-Year-Period Study in Rabbit Trochlea

    PubMed Central

    Li, Dichen; Wang, Kunzheng; Hao, Dingjun; Bian, Weiguo; He, Jiankang; Jin, Zhongmin

    2014-01-01

    Increasing evidences show that subchondral bone may play a significant role in the repair or progression of cartilage damage in situ. However, the exact change of subchondral bone during osteochondral repair is still poorly understood. In this paper, biphasic osteochondral composite scaffolds were fabricated by 3D printing technology using PEG hydrogel and β-TCP ceramic and then implanted in rabbit trochlea within a critical size defect model. Animals were euthanized at 1, 2, 4, 8, 16, 24, and 52 weeks after implantation. Histological results showed that hyaline-like cartilage formed along with white smooth surface and invisible margin at 24 weeks postoperatively, typical tidemark formation at 52 weeks. The repaired subchondral bone formed from 16 to 52 weeks in a “flow like” manner from surrounding bone to the defect center gradually. Statistical analysis illustrated that both subchondral bone volume and migration area percentage were highly correlated with the gross appearance Wayne score of repaired cartilage. Therefore, subchondral bone migration is related to cartilage repair for critical size osteochondral defects. Furthermore, the subchondral bone remodeling proceeds in a “flow like” manner and repaired cartilage with tidemark implies that the biphasic PEG/β-TCP composites fabricated by 3D printing provides a feasible strategy for osteochondral tissue engineering application. PMID:25177697

  14. Modeling of the Near Field Coupling Between an External Loop and an Implantable Spiral Chip Antennas in Biosensor Systems

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.; Miranda, Felix A.

    2006-01-01

    In this paper, the near field coupling between an external hand-held loop antenna and an implantable miniature (1x1 mm) printed square spiral chip antenna used in bio-MEMS sensors for contact-less powering and RF telemetry is investigated. The loop and the spiral are inductively coupled and effectively form a transformer. The numerical results include the quasi-stationary magnetic field pattern of the implanted antenna, near zone wave impedance as a function of the radial distance and the values of the lumped elements in the equivalent circuit model for the transformer.

  15. Osteochondral Autograft Transplantation Surgery for Metacarpal Head Defects.

    PubMed

    Kitay, Alison; Waters, Peter M; Bae, Donald S

    2016-03-01

    Post-traumatic osteonecrosis of the metacarpal head is a challenging problem, particularly in younger patients in whom arthroplasty may not be a durable option. Although several osteochondral reconstructive options have been proposed, some are associated with considerable donor site morbidity and/or require the use of internal fixation. We present an application of osteochondral autograft transplantation surgery as a treatment option for focal metacarpal head lesions. An osteochondral plug from the non-weight-bearing articular surface of the knee is transferred and press-fit to resurface a focal metacarpal head defect. The technical pearls and pitfalls are reviewed, and an illustrative case is presented.

  16. Electromagnetic versus electrical coupling of personal frequency modulation (FM) receivers to cochlear implant sound processors.

    PubMed

    Schafer, Erin C; Romine, Denise; Musgrave, Elizabeth; Momin, Sadaf; Huynh, Christy

    2013-01-01

    Previous research has suggested that electrically coupled frequency modulation (FM) systems substantially improved speech-recognition performance in noise in individuals with cochlear implants (CIs). However, there is limited evidence to support the use of electromagnetically coupled (neck loop) FM receivers with contemporary CI sound processors containing telecoils. The primary goal of this study was to compare speech-recognition performance in noise and subjective ratings of adolescents and adults using one of three contemporary CI sound processors coupled to electromagnetically and electrically coupled FM receivers from Oticon. A repeated-measures design was used to compare speech-recognition performance in noise and subjective ratings without and with the FM systems across three test sessions (Experiment 1) and to compare performance at different FM-gain settings (Experiment 2). Descriptive statistics were used in Experiment 3 to describe output differences measured through a CI sound processor. Experiment 1 included nine adolescents or adults with unilateral or bilateral Advanced Bionics Harmony (n = 3), Cochlear Nucleus 5 (n = 3), and MED-EL OPUS 2 (n = 3) CI sound processors. In Experiment 2, seven of the original nine participants were tested. In Experiment 3, electroacoustic output was measured from a Nucleus 5 sound processor when coupled to the electromagnetically coupled Oticon Arc neck loop and electrically coupled Oticon R2. In Experiment 1, participants completed a field trial with each FM receiver and three test sessions that included speech-recognition performance in noise and a subjective rating scale. In Experiment 2, participants were tested in three receiver-gain conditions. Results in both experiments were analyzed using repeated-measures analysis of variance. Experiment 3 involved electroacoustic-test measures to determine the monitor-earphone output of the CI alone and CI coupled to the two FM receivers. The results in Experiment 1 suggested

  17. Current management of talar osteochondral lesions

    PubMed Central

    Gianakos, Arianna L; Yasui, Youichi; Hannon, Charles P; Kennedy, John G

    2017-01-01

    Osteochondral lesions of the talus (OLT) occur in up to 70% of acute ankle sprains and fractures. OLT have become increasingly recognized with the advancements in cartilage-sensitive diagnostic imaging modalities. Although OLT may be treated nonoperatively, a number of surgical techniques have been described for patients whom surgery is indicated. Traditionally, treatment of symptomatic OLT have included either reparative procedures, such as bone marrow stimulation (BMS), or replacement procedures, such as autologous osteochondral transplantation (AOT). Reparative procedures are generally indicated for OLT < 150 mm2 in area. Replacement strategies are used for large lesions or after failed primary repair procedures. Although short- and medium-term results have been reported, long-term studies on OLT treatment strategies are lacking. Biological augmentation including platelet-rich plasma and concentrated bone marrow aspirate is becoming increasingly popular for the treatment of OLT to enhance the biological environment during healing. In this review, we describe the most up-to-date clinical evidence of surgical outcomes, as well as both the mechanical and biological concerns associated with BMS and AOT. In addition, we will review the recent evidence for biological adjunct therapies that aim to improve outcomes and longevity of both BMS and AOT procedures. PMID:28144574

  18. Osteochondritis dissecans of the capitellum in adolescents

    PubMed Central

    van Bergen, Christiaan JA; van den Ende, Kimberly IM; ten Brinke, Bart; Eygendaal, Denise

    2016-01-01

    Osteochondritis dissecans (OCD) is a disorder of articular cartilage and subchondral bone. In the elbow, an OCD is localized most commonly at the humeral capitellum. Teenagers engaged in sports that involve repetitive stress on the elbow are at risk. A high index of suspicion is warranted to prevent delay in the diagnosis. Plain radiographs may disclose the lesion but computed tomography and magnetic resonance imaging are more accurate in the detection of OCD. To determine the best treatment option it is important to differentiate between stable and unstable OCD lesions. Stable lesions can be initially treated nonoperatively with elbow rest or activity modification and physical therapy. Unstable lesions and stable lesions not responding to conservative therapy require a surgical approach. Arthroscopic debridement and microfracturing has become the standard initial procedure for treatment of capitellar OCD. Numerous other surgical options have been reported, including internal fixation of large fragments and osteochondral autograft transfer. The aim of this article is to provide a current concepts review of the etiology, clinical presentation, diagnosis, treatment, and outcomes of elbow OCD. PMID:26925381

  19. Osteochondral Lesions of the Talar Dome.

    PubMed

    Stone

    1996-03-01

    Osteochondral lesions of the talar dome are relatively common causes of ankle pain and disability. Trauma is the most common cause, but ischemic necrosis, en-docrine disorders, and genetic factors may have etiologic significance. Medial lesions are usually located posteriorly on the dome of the talus, whereas lateral lesions are most frequently located anteriorly. Although the staging system described by Berndt and Harty remains popular, it may not accurately reflect the integrity of the articular cartilage. Small lesions of the talar dome may be present despite a normal appearance on plain radiography. Bone scintigraphy may show increased radionuclide uptake in the talar dome. Magnetic resonance imaging is also sensitive for identifying intraosseous abnormalities in the talus and has the added benefit of revealing other types of soft-tissue lesions not visible on routine radiographic studies. Computed tomography remains the imaging technique of choice when delineation of a bone fragment is desired. Nonoperative management of osteochondral lesions, including restricted weight-bearing and/or immobilization, is recommended unless a loose fragment is clearly present. Surgical options include drilling (usually reserved for intact lesions), debridement of the lesion with curettage or abrasion of the bone bed, internal fixation of the fragment, and bone grafting. Recent technical advances allow these procedures to be performed arthroscopically, with potential reduction of surgical trauma, length of hospital stay, and complication rates.

  20. Intraoral corrosion resulting from coupling dental implants and restorative metallic systems.

    PubMed

    Lemons, J E; Lucas, L C; Johansson, B I

    1992-01-01

    Materials used for the construction of dental restorations and implants include a wide range of metals and alloys, ceramics and carbons, and polymers. When metals and alloys are placed in direct contact in the oral cavity, a galvanic cell can be formed that may compromise the longevity of one or more of the materials in the couple. In vitro electrochemical corrosion analyses have proven to be a valuable tool for providing guidance on the selection of metallic materials. These analyses can provide basic data on electrochemical potentials, current rates, and the evaluation of galvanic corrosion conditions. This article seeks to provide the clinician with information that can be valuable in the selection of metallic materials that may be placed in direct contact with one another in the oral cavity.

  1. Osteochondral repair by a novel interconnecting collagen-hydroxyapatite substitute: a large-animal study.

    PubMed

    Sosio, Corrado; Di Giancamillo, Alessia; Deponti, Daniela; Gervaso, Francesca; Scalera, Francesca; Melato, Marco; Campagnol, Marino; Boschetti, Federica; Nonis, Alessandro; Domeneghini, Cinzia; Sannino, Alessandro; Peretti, Giuseppe Michele

    2015-02-01

    A novel three-dimensional bicomponent substitute made of collagen type I and hydroxyapatite was tested for the repair of osteochondral lesions in a swine model. This scaffold was assembled by a newly developed method that guarantees the strict integration between the organic and the inorganic parts, mimicking the biological tissue between the chondral and the osseous phase. Thirty-six osteochondral lesions were created in the trochlea of six pigs; in each pig, two lesions were treated with scaffolds seeded with autologous chondrocytes (cell+group), two lesions were treated with unseeded scaffolds (cell- group), and the two remaining lesions were left untreated (untreated group). After 3 months, the animals were sacrificed and the newly formed tissue was analyzed to evaluate the degree of maturation. The International Cartilage Repair Society (ICRS) macroscopic assessment showed significantly higher scores in the cell- and untreated groups when compared with the cell+ group. Histological evaluation showed the presence of repaired tissue, with fibroblast-like and hyaline-like areas in all groups; however, with respect to the other groups, the cell- group showed significantly higher values in the ICRS II histological scores for "cell morphology" and for the "surface/superficial assessment." While the scaffold seeded with autologous chondrocytes promoted the formation of a reparative tissue with high cellularity but low glycosaminoglycans (GAG) production, on the contrary, the reparative tissue observed with the unseeded scaffold presented lower cellularity but higher and uniform GAG distribution. Finally, in the lesions treated with scaffolds, the immunohistochemical analysis showed the presence of collagen type II in the peripheral part of the defect, indicating tissue maturation due to the migration of local cells from the surroundings. This study showed that the novel osteochondral scaffold was easy to handle for surgical implantation and was stable within the site

  2. Optical integration of laterally modified multiple quantum well structures by implantation enhanced intermixing to realize gain coupled DFB lasers

    NASA Astrophysics Data System (ADS)

    Hofsäß, V.; Kuhn, J.; Kaden, C.; Härle, V.; Bolay, H.; Scholz, F.; Schweizer, H.; Hillmer, H.; Lösch, R.; Schlapp, W.

    1995-12-01

    We report on the realization of gain coupled distributed feedback (GC-DFB) lasers using masked implantation enhanced intermixing (MIEI) in a full planar technology. The process requires only planar epitaxy steps to minimize ion straggling. We present a detailed investigation on the integration processing steps as implantation, subsequent annealing and regrowth with InP (MOCVD). We also discuss critical technology steps. Surface morphology depends very sensitive on implantation and annealing. Nonradiative recombination caused by defects leads to high losses in optical devices. We achieve good results for an AsH 3 stabilized annealing step in a MOCVD equipment, compared to rapid thermal annealing (RTA), which proceeds as the second epitaxial step. Photoluminescence (PL) studies show the excellent interface quality. High homogeneity and small linewidth after the integration process indicate sufficient quality to realize electrical gain coupled DFB-laser devices by IEI.

  3. The maturity of tissue-engineered cartilage in vitro affects the repairability for osteochondral defect.

    PubMed

    Jin, Cheng Zhe; Cho, Jae-Ho; Choi, Byung Hyune; Wang, Li Ming; Kim, Moon Suk; Park, So Ra; Yoon, Jeong Ho; Yun, Jung Ho; Oh, Hyun Ju; Min, Byoung-Hyun

    2011-12-01

    Cartilage tissue engineering using cells and biocompatible scaffolds has emerged as a promising approach to repair of cartilage damage. To date, however, no engineered cartilage has proven to be equivalent to native cartilage in terms of biochemical and compression properties, as well as histological features. An alternative strategy for cartilage engineering is to focus on the in vivo regeneration potential of immature engineered cartilage. Here, we used a rabbit model to evaluate the extent to which the maturity of engineered cartilage influenced the remodeling and integration of implanted extracellular matrix scaffolds containing allogenous chondrocytes. Full-thickness osteochondral defects were created in the trochlear groove of New Zealand white rabbits. Left knee defects were left untreated as a control (group 1), and right knee defects were implanted with tissue-engineered cartilage cultured in vitro for 2 days (group 2), 2 weeks (group 3), or 4 weeks (group 4). Histological, chemical, and compression assays of engineered cartilage in vitro showed that biochemical composition became more cartilagenous, and biomechanical property for compression gradually increased with culture time. In an in vivo study, gross imaging and histological observation at 1 and 3 months after implanting in vitro-cultured engineered cartilage showed that defects in groups 3 and 4 were repaired with hyaline cartilage-like tissue, whereas defects were only partially filled with fibrocartilage after 1 month in groups 1 and 2. At 3 months, group 4 showed striking features of hyaline cartilage tissue, with a mature matrix and a columnar arrangement of chondrocytes. Zonal distribution of type II collagen was most prominent, and the International Cartilage Repair Society score was also highest at this time. In addition, the subchondral bone was well ossified. In conclusion, in vivo engineered cartilage was remodeled when implanted; however, its extent to maturity varied with cultivation

  4. Tibial plateau lesions. Surface reconstruction with a biomimetic osteochondral scaffold: Results at 2 years of follow-up.

    PubMed

    Kon, Elizaveta; Filardo, Giuseppe; Venieri, Giulia; Perdisa, Francesco; Marcacci, Maurilio

    2014-12-01

    Tibial plateau articular pathology caused by post-traumatic or degenerative lesions is a challenge for the orthopaedic surgeon and can lead to early osteoarthritis. The aim of the present study was to evaluate the results of treatment of these complex defects with implantation of an osteochondral scaffold, which is designed to target the cartilage surface and to reconstruct joint anatomy by addressing the entire osteochondral unit. Eleven patients (5 female and 6 male) with a mean age of 37.3 ± 11.0 years and osteochondral lesions of the tibial plateau (mean 5.1 ± 2.7 cm(2); range 3.0-12.5 cm(2)) were treated with the implantation of an osteochondral biomimetic collagen-hydroxyapatite scaffold (Maioregen(®), Fin-Ceramica, Faenza, Italy). Comorbidities were addressed taking care to restore the correct limb alignment. Patients were evaluated pre-operatively and prospectively followed-up for 2 years using the International Knee Documentation Committee (IKDC) subjective and objective scores; activity level was documented using the Tegner score. Three patients experienced minor adverse events. No patients required further surgery for treatment failure during the study follow-up period, and 8 patients (72.7%) reported a marked improvement. The IKDC subjective score improved from 42.5 ± 10.2 before treatment to 69.8 ± 19.0 at 12 months (p<0.05), with stable results at 24 months. The IKDC objective score increased from 27.3% normal and nearly normal knees before treatment to 85.7% normal and nearly normal knees at 24 months of follow-up. The Tegner score increased from 2.3 ± 2.1 before treatment to 4.8 ± 2.4 at 12 months (p<0.05), and was stable at the final follow-up. The present study on the implantation of an osteochondral scaffold for the treatment of tibial plateau lesions showed a promising clinical outcome at short-term follow-up, which indicates that this procedure can be considered as a possible treatment option, even in these complex defects, when

  5. Current Concepts: Osteochondritis Dissecans of the Capitellum and the Role of Osteochondral Autograft Transplantation.

    PubMed

    Kirsch, Jacob M; Thomas, Jared; Bedi, Asheesh; Lawton, Jeffrey N

    2016-12-01

    Background: Osteochondritis dissecans (OCD) of the capitellum is a painful condition, which often affects young throwing athletes. Our current understanding regarding the etiology, risks factors, diagnosis, and efficacy of the available treatment options has expanded over recent years, however remains suboptimal. Recent data on patient-reported outcomes following osteochondral autograft transplantation (OAT) for the treatment of large osteochondral lesions of the capitellum have been promising but limited. This review seeks to critically analyze and summarize the available literature on the etiology, diagnosis, and reported outcomes associated with OCD of the capitellum and the use of OAT for its treatment. Methods: A comprehensive literature search was conducted. Unique and customized search strategies were formulated in PubMed, Embase, Scopus, Web of Science, and CENTRAL. Combinations of keywords and controlled vocabulary terms were utilized in order to cast a broad net. Relevant clinical, biomechanical, anatomic and imaging studies were reviewed along with recent review articles, and case series. Results: Forty-three articles from our initial literature search were found to be relevant for this review. The majority of these articles were either review articles, clinical studies, anatomic or imaging studies or biomechanical studies. Conclusions: Current evidence suggests that OAT may lead to better and more consistent outcomes than previously described methods for treating large OCD lesions of the capitellum.

  6. [Osteochondritis dissecans of the acetabulum. Apropos of a case].

    PubMed

    Hardy, P; Hinojosa, J F; Coudane, H; Sommelet, J; Benoit, J

    1992-01-01

    Osteochondritis dissecans acetabuli is a rare affection. The observation presented is one of a 23 year old man, who presented hip blockages in external flexion rotation. X-ray only allowed to find a sequestrum in the acetabulum by tomography-Arthroscanner confirmed the osteochondritis without cartilage rupture. Arthroscopy eliminated a cartilage lesion and directed towards a cavity filled by spongious bone through an extra articular approach.

  7. Novel nanostructured scaffold for osteochondral regeneration: pilot study in horses.

    PubMed

    Kon, E; Mutini, A; Arcangeli, E; Delcogliano, M; Filardo, G; Nicoli Aldini, N; Pressato, D; Quarto, R; Zaffagnini, S; Marcacci, M

    2010-06-01

    The present in vivo preliminary experiment is aimed at testing mechanical and biological behaviour of a new nano-structured composite multilayer biomimetic scaffold for the treatment of chondral and osteochondral defects. The three-dimensional biomimetic scaffold (Fin-Ceramica Faenza S.p.A., Faenza-Italy) was obtained by nucleating collagen fibrils with hydroxyapatite nanoparticles, in two configurations, bi- and tri-layered, to reproduce, respectively, chondral and osteochondral anatomy. Chondral defects (lateral condyle) and deep osteochondral defects (medial condyle) were made in the distal epiphysis of the third metacarpal bone of both forelimbs of two adult horses and treated respectively with the chondral and osteochondral grafts. Both animals were euthanised six months follow up. The images obtained at the second look arthroscopy evaluation, performed two months after surgery, demonstrated good filling of the chondral and osteo-chondral defects without any inflammatory reaction around and inside the lesions. At the histological analysis the growth of trabecular bone in the osteochondral lesion was evident. Only in one case, the whole thickness of the osteochondral lesion was filled by fibrocartilaginous tissue. The formation of a tidemark line was evident at the interface with the newly formed bone. Newly formed fibrocartilaginous tissue was present in the area of the chondral defect. Initial alignment of the collagen fibres was recognisable with polarised light in both groups. The results of the present pilot study showed that this novel osteochondral and chondral scaffold may act as a suitable matrix to facilitate orderly regeneration of bone and hyaline-like cartilage. Copyright 2010 John Wiley & Sons, Ltd.

  8. The effect of storage medium tonicity on osteochondral autograft plug diameter.

    PubMed

    Fening, Stephen D; Mihnovets, Jonathon; Jones, Morgan H; Midura, Ronald J; Miniaci, Anthony

    2011-02-01

    The purpose of this study was to investigate the effect of differing storage medium on osteochondral plug diameter. Four storage conditions were evaluated: air, hypotonic solution (sterile water), isotonic saline solution (0.9% sodium chloride), and hypertonic saline solution (3.0% sodium chloride). Four osteochondral plugs were acquired (4.5-mm harvesting system) from each of 10 fresh calf femurs and randomized to 1 of 4 storage media (N = 40). Micro-computed tomography was used to evaluate the precise diameter of each plug. After a time 0 scan, each plug was placed in a designated storage medium and rescanned at 3 time points over approximately 1 hour. A region of interest was identified from approximately 1 to 6 mm proximal to the tidemark. Custom software automatically calculated the diameter of each plug. The time 0 plug diameter (mean ± 95% confidence interval) for all specimens was 4.66 ± 0.01 mm. There were no significant differences between any of the groups at the baseline scan. There were also no significant differences between the time 0 and subsequent scans of the unsubmerged specimens. However, all of the liquid solutions (hypertonic, isotonic, and hypotonic) resulted in a significant increase in diameter from their baseline scans (P < .05), indicating that a cause may be increased extracellular matrix fluid pressure. Placing an osteochondral plug in a liquid solution increased the diameter of the subchondral bone. Size increase from the storage medium appeared to level off within 14 minutes after placement in solution. Increases in diameter of the plug may alter the ease of insertion of the graft, possibly increasing contact pressure on cartilage during plug implantation. Copyright © 2011 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  9. Cartilage repair with osteochondral autografts in sheep: effect of biophysical stimulation with pulsed electromagnetic fields.

    PubMed

    Benazzo, Franco; Cadossi, Matteo; Cavani, Francesco; Fini, Milena; Giavaresi, Gianluca; Setti, Stefania; Cadossi, Ruggero; Giardino, Roberto

    2008-05-01

    The effect of pulsed electromagnetic fields (PEMFs) on the integration of osteochondral autografts was evaluated in sheep. After osteochondral grafts were performed, the animals were treated with PEMFs for 6 h/day or sham-treated. Six animals were sacrificed at 1 month. Fourteen animals were treated for 2 months and sacrificed at 6 months. At 1 month, the osteogenic activity at the transplant-host subchondral bone interface was increased in PEMF-treated animals compared to controls. Articular cartilage was healthy in controls and stimulated animals. At 6 months, complete resorption was observed in four control grafts only. Cyst-like resorption areas were more frequent within the graft of sham-treated animals versus PEMF-treated. The average volume of the cysts was not significantly different between the two groups; nevertheless, analysis of the variance of the volumes demonstrated a significant difference. The histological score showed no significant differences between controls and stimulated animals, but the percentage of surface covered by fibrous tissue was higher in the control group than in the stimulated one. Interleukin-1 and tumor necrosis factor-alpha concentration in the synovial fluid was significantly lower, and transforming growth factor-beta1 was significantly higher, in PEMF-treated animals compared to controls. One month after osteochondral graft implantation, we observed larger bone formation in PEMF-treated grafts which favors early graft stabilization. In the long term, PEMF exposure limited the bone resorption in subchondral bone; furthermore, the cytokine profile in the synovial fluid was indicative of a more favorable articular environment for the graft.

  10. The effect of platform switching on the levels of metal ion release from different implant-abutment couples.

    PubMed

    Alrabeah, Ghada O; Knowles, Jonathan C; Petridis, Haralampos

    2016-06-30

    The improved peri-implant bone response demonstrated by platform switching may be the result of reduced amounts of metal ions released to the surrounding tissues. The aim of this study was to compare the levels of metal ions released from platform-matched and platform-switched implant-abutment couples as a result of accelerated corrosion. Thirty-six titanium alloy (Ti-6Al-4V) and cobalt-chrome alloy abutments were coupled with titanium cylinders forming either platform-switched or platform-matched groups (n=6). In addition, 18 unconnected samples served as controls. The specimens were subjected to accelerated corrosion by static immersion in 1% lactic acid for 1 week. The amount of metal ions ion of each test tube was measured using inductively coupled plasma mass spectrometry. Scanning electron microscope (SEM) images and energy dispersive spectroscopy X-ray analyses were performed pre- and post-immersion to assess corrosion at the interface. The platform-matched groups demonstrated higher ion release for vanadium, aluminium, cobalt, chrome, and molybdenum compared with the platform-switched groups (P<0.05). Titanium was the highest element to be released regardless of abutment size or connection (P<0.05). SEM images showed pitting corrosion prominent on the outer borders of the implant and abutment platform surfaces. In conclusion, implant-abutment couples underwent an active corrosion process resulting in metal ions release into the surrounding environment. The highest amount of metal ions released was recorded for the platform-matched groups, suggesting that platform-switching concept has a positive effect in reducing the levels of metal ion release from the implant-abutment couples.

  11. Isolated osteochondral fracture of the patella without patellar dislocation.

    PubMed

    Bhatt, Jay; Montalban, Antonio Santa Cruz; Wang, Kook Hyun; Lee, Hee Du; Nha, Kyung Wook

    2011-01-03

    Chondral fractures of the patella are associated with acute dislocation of the patella. Osteochondral fracture in patellar dislocation is located in the medial facet of the patella. This article presents a case of a 15-year-old female ballerina with isolated displaced osteochondral fracture of the patella without patellar dislocation. She had no history of trauma. A Merchant's view of both knees showed mild subluxation of the patella, a small fragment on the lateral aspect of the knee, and a small defect of the centromedial patella. Axial magnetic resonance imaging (MRI) revealed an osteochondral fragment measuring 13 mm medial to the patella. However, the medial patellofemoral ligament and medial retinaculum were intact. An effusion on the medial side of the patella consistent with hemarthrosis was observed. An absence of a contusion or bone bruise on the lateral femoral condyle was shown. The loose body was removed arthroscopically. Intraoperative findings included a 1.5×2 cm osteochondral fragment. It is unusual that the osteochondral patellar defect site in this patient was in the inferior and central areas of the patella. Patellar chondral fractures without dislocation or patella fracture are rare. Therefore, the possibility of a trivial trauma leading to an osteochondral fracture should be kept in mind in adolescent and young adults who present with knee pain and hemarthrosis. Copyright 2011, SLACK Incorporated.

  12. A new bi-layered scaffold for osteochondral tissue regeneration: In vitro and in vivo preclinical investigations.

    PubMed

    Sartori, M; Pagani, S; Ferrari, A; Costa, V; Carina, V; Figallo, E; Maltarello, M C; Martini, L; Fini, M; Giavaresi, G

    2017-01-01

    Current treatments for acute or degenerative chondral and osteochondral lesions are in need of improvement, as these types of injuries lead to disability and worsen the quality of life in a high percentage of patients. The aim of this study was to develop a new bi-layered scaffold for osteochondral tissue regeneration through a "biomimetic" and "bioinspired" approach. For chondral regeneration, the scaffold was realized with an organic compound (type I collagen), while for the regeneration of the subchondral layer, bioactive magnesium-doped hydroxyapatite (Mg/HA) crystals were co-precipitated with the organic component of the scaffold. The entire scaffold structure was stabilized with a cross-linking agent, highly reactive bis-epoxyde (1,4-butanediol diglycidyl ether - BDDGE 1wt%). The developed scaffold was then characterized for its physico-chemical characteristics. Its structure and adhesion strength between the integrated layers were investigated. At the same time, in vitro cell culture studies were carried out to examine the ability of chondral and bone scaffold layers to separately support adhesion, proliferation and differentiation of human mesenchymal stem cells (hMSCs) into chondrocytes and osteoblasts, respectively. Moreover, an in vivo study with nude mice, transplanted with osteochondral scaffolds plain or engineered with undifferentiated hMSCs, was also set up with 4 and 8-week time points. The results showed that chondral and bone scaffold layers represented biocompatible scaffolds able to sustain hMSCs attachment and proliferation. Moreover, the association of scaffold stimuli and differentiation medium, induced hMSCs chondrogenic and osteogenic differentiation and deposition of extracellular matrix (ECM). The ectopic implantation of the engineered osteochondral scaffolds indicated that hMSCs were able to colonize the osteochondral scaffold in depth. The scaffold appeared permissive to tissue growth and penetration, ensuring the diffusion of

  13. Emerging genetic basis of osteochondritis dissecans

    PubMed Central

    Bates, J. Tyler; Jacobs, John C.; Shea, Kevin G.; Oxford, Julia Thom

    2014-01-01

    Genome-wide association studies provide an unbiased approach in the identification of genes that increase the risk for osteochondritis dissecans (OCD). OCD is a disorder of the bone and cartilage that affects humans, horses, pigs, dogs, and other mammals. Recent genome-wide association studies in humans, horses, and pigs are reviewed and genes identified. The identified genes tended to cluster with respect to function and biological processes such as the protein secretion pathway, extracellular matrix molecules, and growth plate maturation. Genome-wide association studies in humans are a critical next step in the effort to provide a better understanding of the causes of OCD, which will, in turn, allow preventive strategies for treatment of adolescent and young adults who are at risk for the development of degenerative joint disease due to the effects of OCD. PMID:24698039

  14. Osteochondral diseases and fibrodysplasia ossificans progressiva.

    PubMed

    Morales-Piga, Antonio; Kaplan, Frederick S

    2010-01-01

    Osteochondrodysplasias like thanatophoric dysplasia, osteogenesis imperfecta, achondroplasia, and other genetic skeletal disorders like fibrodysplasia ossificans progressiva are infrequently seen in clinical practice. In cases of sporadic achondroplasia as well as in fibrodysplasia ossificans progressiva, there is a strong association with paternal age, a relationship that is less evident in other genetic osteochondral diseases. No other constitutional or environmental factor has proven to be associated with these disorders. The use of prenatal ultrasonography as a routine component of prenatal care is crucial in the early suspicion of osteochondrodysplasias whereas definitive diagnosis is usually obtained by pre-natal molecular analysis. In the case of fibrodysplasia ossificans progressiva, recognition of congenital great toe malformations associated with rapidly-appearing soft tissue swelling is sufficient to make the proper clinical diagnosis, which can be confirmed by genetic testing. Large regional centres will improve diagnosis performance, provide accurate genetic counselling, and ensure an integral assistance for these often severe and incapacitating conditions.

  15. Osteochondral Diseases and Fibrodysplasia Ossificans Progressiva

    PubMed Central

    Kaplan, Frederick S.

    2016-01-01

    Osteochondrodysplasias like thanatophoric dysplasia, osteogenesis imperfecta, achondroplasia, and other genetic skeletal disorders like fibrodysplasia ossificans progressiva are infrequently seen in clinical practice. In cases of sporadic achondroplasia as well as in fibrodysplasia ossificans progressiva, there is a strong association with paternal age, a relationship that is less evident in other genetic osteochondral diseases. No other constitutional or environmental factor has proven to be associated with these disorders. The use of prenatal ultrasonography as a routine component of prenatal care is crucial in the early suspicion of osteochondrodysplasias whereas definitive diagnosis is usually obtained by pre-natal molecular analysis. In the case of fibrodysplasia ossificans progressiva, recognition of congenital great toe malformations associated with rapidly–appearing soft tissue swelling is sufficient to make the proper clinical diagnosis, which can be confirmed by genetic testing. Large regional centres will improve diagnosis performance, provide accurate genetic counselling, and ensure an integral assistance for these often severe and incapacitating conditions. PMID:20824454

  16. Effect of lateral meniscectomy and osteochondral grafting of a lateral femoral condylar defect on contact mechanics: a cadaveric study in dogs

    PubMed Central

    2013-01-01

    Background Osteochondral autograft transfer (OAT) aims at restoring normal articular cartilage surface geometry and articular contact mechanics. To date, no studies have evaluated the contact mechanics of the canine stifle following OAT. Additionally, there are no studies that evaluated the role of the meniscus in contact mechanics following OAT in human or canine femorotibial joints. The objective of this study was to measure the changes in femorotibial contact areas (CA), mean contact pressure (MCP) and peak contact pressure (PCP) before and after osteochondral autograft transplantation (OAT) of a simulated lateral femoral condylar cartilage defect with an intact lateral meniscus and following lateral meniscectomy. Results With an intact lateral meniscus, creation of an osteochondral defect caused a decrease in MCP and PCP by 11% and 30%, respectively, compared to the intact stifle (p < 0.01). With an intact meniscus, implanting an osteochondral graft restored MCP and PCP to 96% (p = 0.56) and 92% (p = 0.41) of the control values. Lateral meniscectomy with grafting decreased CA by 54% and increased PCP by 79% compared to the intact stifle (p < 0.01). Conclusions OAT restored contact pressures in stifles with a simulated lateral condylar defect when the meniscus was intact. The lateral meniscus has a significant role in maintaining normal contact pressures in both stifles with a defect or following OAT. Meniscectomy should be avoided when a femoral condylar defect is present and when performing OAT. PMID:23522348

  17. Osteochondral repair in hemophilic ankle arthropathy: from current options to future perspectives

    PubMed Central

    BUDA, ROBERTO; CAVALLO, MARCO; CASTAGNINI, FRANCESCO; FERRANTI, ENRICO; NATALI, SIMONE; GIANNINI, SANDRO

    2015-01-01

    Young hemophilic patients are frequently affected by ankle arthropathy. At the end stage of the disease, the current treatments are arthrodesis and arthroplasty, which have significant drawbacks. Validated procedures capable of slowing down or even arresting the progression towards the end stage are currently lacking. This review aims to discuss the rationale for and feasibility of applying, in mild hemophilic ankle arthropathy, the main techniques currently used to treat osteochondral defects, focusing in particular on ankle distraction, chondrocyte implantation, mesenchymal stem cell transplantation, allograft transplantation and the use of growth factors. To date, ankle distraction is the only procedure that has been successfully used in hemophilic ankle arthropathy. The use of mesenchymal stem cells have recently been evaluated as feasible for osteochondral repair in hemophilic patients. There may be a rationale for the use of growth factors if they are combined with the previous techniques, which could be useful to arrest the progression of the degeneration or delay end-stage procedures. PMID:26904526

  18. [Results of the experimental repair of osteochondral lesions in a pig model using tissue engineering].

    PubMed

    Villalobos Córdoba, F Enrique; Velasquillo Martínez, Cristina; Martínez López, Valentín; Lecona Butrón, Hugo; Reyes Marín, Baltasar; Estrada Villaseñor, Eréndira; Villegas, Castrejón Hilda; Solís Arrieta, Lilia; Espinosa Morales, Rolando; Ponce de León, Clemente Ibarra

    2007-01-01

    To repair experimental osteochondral knee lesions in pigs using tissue engineering. Eight 40-kg pigs underwent surgery. Cartilage and periosteal biopsies of their control knee were taken. Cartilage and periosteal cells were independently isolated, cultured and seeded in biodegradable PGA and PLA polymers that were fixed on the bottom of an osteochondral defect in the pig's experimental knee, with bioabsorbable Mitek implants. Four months later the pigs were sacrificed and the knees were analyzed with nuclear magnetic resonance imaging (NMRI), macroscopic assessment, histology, electron microscopy (EM), scanning electron microscopy (SEM) and SEM element analysis. All the defects were filled with cartilage-like tissue according to the NMRI evaluation and the visual examination. Hyaline-like cartilage was obtained in 3 defects and fibrocartilage in 5. The EM showed chondrocytes in the repair tissue. The SEM showed appropriate integration to the bone and the surrounding tissue. SEM element analysis showed sulphurized matrix attached to the bone with calcium and phosphates as predominant elements. Tissue engineering enabled the production of tissues similar to normal ones. The polymer fixation system was effective.

  19. Effect of porosities of bilayered porous scaffolds on spontaneous osteochondral repair in cartilage tissue engineering

    PubMed Central

    Dong, Jian; Ding, Jiandong

    2015-01-01

    Poly(lactide-co-glycolide)-bilayered scaffolds with the same porosity or different ones on the two layers were fabricated, and the porosity effect on in vivo repairing of the osteochondral defect was examined in a comparative way for the first time. The constructs of scaffolds and bone marrow-derived mesenchymal stem cells were implanted into pre-created osteochondral defects in the femoral condyle of New Zealand white rabbits. After 12 weeks, all experimental groups exhibited good cartilage repairing according to macroscopic appearance, cross-section view, haematoxylin and eosin staining, toluidine blue staining, immunohistochemical staining and real-time polymerase chain reaction of characteristic genes. The group of 92% porosity in the cartilage layer and 77% porosity in the bone layer resulted in the best efficacy, which was understood by more biomechanical mimicking of the natural cartilage and subchondral bone. This study illustrates unambiguously that cartilage tissue engineering allows for a wide range of scaffold porosity, yet some porosity group is optimal. It is also revealed that the biomechanical matching with the natural composite tissue should be taken into consideration in the design of practical biomaterials, which is especially important for porosities of a multi-compartment scaffold concerning connected tissues. PMID:26813511

  20. Osteochondral allograft transplantation in cartilage repair: Graft storage paradigm, translational models, and clinical applications.

    PubMed

    Bugbee, William D; Pallante-Kichura, Andrea L; Görtz, Simon; Amiel, David; Sah, Robert

    2016-01-01

    The treatment of articular cartilage injury and disease has become an increasingly relevant part of orthopaedic care. Articular cartilage transplantation, in the form of osteochondral allografting, is one of the most established techniques for restoration of articular cartilage. Our research efforts over the last two decades have supported the transformation of this procedure from experimental "niche" status to a cornerstone of orthopaedic practice. In this Kappa Delta paper, we describe our translational and clinical science contributions to this transformation: (1) to enhance the ability of tissue banks to process and deliver viable tissue to surgeons and patients, (2) to improve the biological understanding of in vivo cartilage and bone remodeling following osteochondral allograft (OCA) transplantation in an animal model system, (3) to define effective surgical techniques and pitfalls, and (4) to identify and clarify clinical indications and outcomes. The combination of coordinated basic and clinical studies is part of our continuing comprehensive academic OCA transplant program. Taken together, the results have led to the current standards for OCA processing and storage prior to implantation and also novel observations and mechanisms of the biological and clinical behavior of OCA transplants in vivo. Thus, OCA transplantation is now a successful and increasingly available treatment for patients with disabling osteoarticular cartilage pathology.

  1. Engineered osteochondral grafts using biphasic composite solid free-form fabricated scaffolds.

    PubMed

    Schek, Rachel M; Taboas, Juan M; Segvich, Sharon J; Hollister, Scott J; Krebsbach, Paul H

    2004-01-01

    Tissue engineering has provided an alternative to traditional strategies to repair cartilage damaged by injury or degenerative disease. A successful strategy to engineer osteochondral tissue will mimic the natural contour of the articulating surface, achieve native mechanical properties and functional load-bearing ability, and lead to integration with host cartilage and underlying subchondral bone. Image-based design (IBD) and solid free-form (SFF) fabrication can be used to generate scaffolds that are load bearing and match articular geometry. The objective of this study was to utilize materials and biological factors in an integrated approach to regenerate a multitissue interface. Biphasic composite scaffolds manufactured by IBD and SFF fabrication were used to simultaneously generate bone and cartilage in discrete regions and provide for the development of a stable interface between cartilage and subchondral bone. Poly-L-lactic acid/hydroxyapatite composite scaffolds were differentially seeded with fibroblasts transduced with an adenovirus expressing bone morphogenetic protein 7 (BMP-7) in the ceramic phase and fully differentiated chondrocytes in the polymeric phase. After subcutaneous implantation into mice, the biphasic scaffolds promoted the simultaneous growth of bone, cartilage, and a mineralized interface tissue. Within the ceramic phase, the pockets of tissue generated included blood vessels, marrow stroma, and adipose tissue. This combination of IBD and SFF-fabricated biphasic scaffolds with gene and cell therapy is a promising approach to regenerate osteochondral defects.

  2. Bilayer Implants

    PubMed Central

    Schagemann, Jan C.; Rudert, Nicola; Taylor, Michelle E.; Sim, Sotcheadt; Quenneville, Eric; Garon, Martin; Klinger, Mathias; Buschmann, Michael D.; Mittelstaedt, Hagen

    2016-01-01

    Objective To compare the regenerative capacity of 2 distinct bilayer implants for the restoration of osteochondral defects in a preliminary sheep model. Methods Critical sized osteochondral defects were treated with a novel biomimetic poly-ε-caprolactone (PCL) implant (Treatment No. 2; n = 6) or a combination of Chondro-Gide and Orthoss (Treatment No. 1; n = 6). At 19 months postoperation, repair tissue (n = 5 each) was analyzed for histology and biochemistry. Electromechanical mappings (Arthro-BST) were performed ex vivo. Results Histological scores, electromechanical quantitative parameter values, dsDNA and sGAG contents measured at the repair sites were statistically lower than those obtained from the contralateral surfaces. Electromechanical mappings and higher dsDNA and sGAG/weight levels indicated better regeneration for Treatment No. 1. However, these differences were not significant. For both treatments, Arthro-BST revealed early signs of degeneration of the cartilage surrounding the repair site. The International Cartilage Repair Society II histological scores of the repair tissue were significantly higher for Treatment No. 1 (10.3 ± 0.38 SE) compared to Treatment No. 2 (8.7 ± 0.45 SE). The parameters cell morphology and vascularization scored highest whereas tidemark formation scored the lowest. Conclusion There was cell infiltration and regeneration of bone and cartilage. However, repair was incomplete and fibrocartilaginous. There were no significant differences in the quality of regeneration between the treatments except in some histological scoring categories. The results from Arthro-BST measurements were comparable to traditional invasive/destructive methods of measuring quality of cartilage repair. PMID:27688843

  3. Allogenous bone with collagen for repair of deep osteochondral defects.

    PubMed

    Schleicher, Iris; Lips, Katrin S; Sommer, Ursula; Schappat, Ines; Martin, Alexander P; Szalay, Gabor; Schnettler, Reinhard

    2013-12-01

    A scaffold for treatment of deep osteochondral defects should be stable, integrate well, and provide a surface for chondrocytes. To meet these demands, a biphasic scaffold of allogenous sterilized bone with a collagen surface was developed. Integration was tested in the sheep model. Cartilage chips were taken from the nonweight-bearing area of the left knee of 12 sheep and cultured. After 4 wk a second procedure followed and defects of 9.4-mm diameter at the weight-bearing area of the medial femoral condyle of the right knee were created. The sterilized scaffold was inserted and the cultured autologous chondrocytes were dripped onto the surface. After 6 wk, 3 mo, and 6 mo the animals were sacrificed; the explanted femoral condyles were evaluated macroscopically and using histologic, immunohistochemical, and electronmicroscopic methods. After 6 wk the level of the surface was well preserved, after 3 mo parts of the scaffold were sintered but after 6 mo the surface was continuous. Full integration of the allogenous bone could be observed after 6 mo. The surface of the scaffold after 6 wk consisted of bone, but after 3 mo some chondrocytes and after 6 mo a continuous chondral layer could be detected. The biphasic scaffold of allogenous bone and collagen proved to be stable and sufficiently integrated in the short- and midterm interval. Whether the chondrocytes on the surface had been derived from implanted chondrocytes or the scaffold with its surface was sufficiently chondroconductive must be answered in further investigations. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Subchondral chitosan/blood implant-guided bone plate resorption and woven bone repair is coupled to hyaline cartilage regeneration from microdrill holes in aged rabbit knees.

    PubMed

    Guzmán-Morales, J; Lafantaisie-Favreau, C-H; Chen, G; Hoemann, C D

    2014-02-01

    Little is known of how to routinely elicit hyaline cartilage repair tissue in middle-aged patients. We tested the hypothesis that in skeletally aged rabbit knees, microdrill holes can be stimulated to remodel the bone plate and induce a more integrated, voluminous and hyaline cartilage repair tissue when treated by subchondral chitosan/blood implants. New Zealand White rabbits (13 or 32 months old, N = 7) received two 1.5 mm diameter, 2 mm depth drill holes in each knee, either left to bleed as surgical controls or press-fit with a 10 kDa (distal hole: 10K) or 40 kDa (proximal hole: 40K) chitosan/blood implant with fluorescent chitosan tracer. Post-operative knee effusion was documented. Repair tissues at day 0 (N = 1) and day 70 post-surgery (N = 6) were analyzed by micro-computed tomography, and by histological scoring and histomorphometry (SafO, Col-2, and Col-1) at day 70. All chitosan implants were completely cleared after 70 days, without increasing transient post-operative knee effusion compared to controls. Proximal control holes had worse osteochondral repair than distal holes. Both implant formulations induced bone remodeling and improved lateral integration of the bone plate at the hole edge. The 40K implant inhibited further bone repair inside 50% of the proximal holes, while the 10K implant specifically induced a "wound bloom" reaction, characterized by decreased bone plate density in a limited zone beyond the initial hole edge, and increased woven bone (WB) plate repair inside the initial hole (P = 0.016), which was accompanied by a more voluminous and hyaline cartilage repair (P < 0.05 vs control defects). In a challenging aged rabbit model, bone marrow-derived hyaline cartilage repair can be promoted by treating acute drill holes with a biodegradable subchondral implant that elicits bone plate resorption followed by anabolic WB repair within a 70-day repair period. Copyright © 2013 Osteoarthritis Research Society International. Published by

  5. COMPARATIVE MACROSCOPIC STUDY OF OSTEOCHONDRAL DEFECTS PRODUCED IN FEMURS OF RABBITS REPAIRED WITH BIOPOLYMER GEL CANE SUGAR

    PubMed Central

    de Albuquerque, Paulo Cezar Vidal Carneiro; dos Santos, Saulo Monteiro; de Andrade Aguiar, José Lamartine; Filho, Nicodemus Pontes; de Mello, Roberto José Vieira; Costa, Mariana Lúcia Correia Ramos; de Albuquerque Olbertz, Clarissa Miranda Carneiro; de Souza Almeida, Tarciana Mendonça; da Silva Santos, Alessandro Henrique; da Silva, Joacil Carlos

    2015-01-01

    Objective: To study the surface, coloring, consistency, continuity and healing of osteochondral defects produced in the femoral condyles of rabbits and filled with sugar cane biopolymer gel (SCBG), after 90, 120 and 180 days, and in comparison with a control group. Method: Sixteen adult New Zealand white rabbits aged 6 to 7 months, weighing between 2 and 2.5 kg and without locomotor system abnormalities were studied. In all the animals, a defect was made in the femoral condyles of the right and left knees, measuring 3.2 mm in diameter and 4 mm in depth, using a trephine. The animals were divided into two groups: study group formed by the right knees, in which the medial and lateral condyles received implants of SCBG; and control group formed by the left knees, in which the medial and lateral condyles were allowed to heal naturally. The knees were assessed 90, 120 and 180 days after the operation. After the animals had been sacrificed, the anatomical specimens were resected and placed in Bouin's solution. They were then photographed with a Nikon Coolpix 5400® coupled to a Nikon SM2800® stereoscopic loupe, to analyze the surface, coloring, consistency, continuity and healing. Results: The results were evaluated using the chi-square test. There were no significant differences in the macroscopic assessments of healing between the study and control groups. Conclusion: With regard to the surface, coloring, consistency, continuity and healing of the defects, the macroscopic appearance of the tissue repaired with SCBG was similar to that of the control group. PMID:27027057

  6. COMPARATIVE MACROSCOPIC STUDY OF OSTEOCHONDRAL DEFECTS PRODUCED IN FEMURS OF RABBITS REPAIRED WITH BIOPOLYMER GEL CANE SUGAR.

    PubMed

    de Albuquerque, Paulo Cezar Vidal Carneiro; Dos Santos, Saulo Monteiro; de Andrade Aguiar, José Lamartine; Filho, Nicodemus Pontes; de Mello, Roberto José Vieira; Costa, Mariana Lúcia Correia Ramos; de Albuquerque Olbertz, Clarissa Miranda Carneiro; de Souza Almeida, Tarciana Mendonça; da Silva Santos, Alessandro Henrique; da Silva, Joacil Carlos

    2011-01-01

    To study the surface, coloring, consistency, continuity and healing of osteochondral defects produced in the femoral condyles of rabbits and filled with sugar cane biopolymer gel (SCBG), after 90, 120 and 180 days, and in comparison with a control group. Sixteen adult New Zealand white rabbits aged 6 to 7 months, weighing between 2 and 2.5 kg and without locomotor system abnormalities were studied. In all the animals, a defect was made in the femoral condyles of the right and left knees, measuring 3.2 mm in diameter and 4 mm in depth, using a trephine. The animals were divided into two groups: study group formed by the right knees, in which the medial and lateral condyles received implants of SCBG; and control group formed by the left knees, in which the medial and lateral condyles were allowed to heal naturally. The knees were assessed 90, 120 and 180 days after the operation. After the animals had been sacrificed, the anatomical specimens were resected and placed in Bouin's solution. They were then photographed with a Nikon Coolpix 5400(®) coupled to a Nikon SM2800(®) stereoscopic loupe, to analyze the surface, coloring, consistency, continuity and healing. The results were evaluated using the chi-square test. There were no significant differences in the macroscopic assessments of healing between the study and control groups. With regard to the surface, coloring, consistency, continuity and healing of the defects, the macroscopic appearance of the tissue repaired with SCBG was similar to that of the control group.

  7. The effects of ion implantation on the tribology of perfluoropolyether-lubricated 440C stainless steel couples

    NASA Technical Reports Server (NTRS)

    Shogrin, Bradley; Jones, William R., Jr.; Wilbur, Paul J.; Pilar, Herrera-Fierro; Williamson, Don L.

    1995-01-01

    The lubricating lifetime of thin films of a perfluoropolyether (PFPE) based on hexafluoropropene oxide in the presence of ion implanted 440C stainless steel is presented. Stainless steel discs, either unimplanted or implanted with N2, C, Ti, Ti + N2, or Ti + C had a thin film of PFPE (60-400 A) applied to them reproducibly (+/- 20 percent) and uniformly (+/- 15 percent) using a device developed for this study. The lifetimes of these films were quantified by measuring the number of sliding-wear cycles required to induce an increase in the friction coefficient from an initial value characteristic of the lubricated wear couple to a final, or failure value, characteristic of an unlubricated, unimplanted couple. The tests were performed in a dry nitrogen atmosphere (less than 1 percent RH) at room temperature using a 3 N normal load with a relative sliding speed of 0.05 m/s. The lubricated lifetime of the 440C couple was increased by an order of magnitude by implanting the disc with Ti. Ranked from most to least effective, the implanted species were: Ti; Ti+C; unimplanted; N2; C approximately equals Ti+N2. The mechanism postulated to explain these results involves the formation of a passivating or reactive layer which inhibits or facilitates the production of active sites. The corresponding surface microstructures induced by ion implantation, obtained using x-ray diffraction and conversion electron Mossbauer spectroscopy, ranked from most to least effective in enhancing lubricant lifetime were: amorphous Fe-Cr-Ti; amorphous Fe-Cr-Ti-C + TiC; unimplanted; epsilon-(Fe,Cr)(sub x)N, x = 2 or 3; amorphous Fe-Cr-C approximately equals amorphous Fe-Cr-Ti-N.

  8. Evaluation of a hybrid scaffold/cell construct in repair of high-load-bearing osteochondral defects in rabbits.

    PubMed

    Shao, Xin Xin; Hutmacher, Dietmar W; Ho, Saey Tuan; Goh, James C H; Lee, Eng Hin

    2006-03-01

    The objective of this study was to evaluate the feasibility and potential of a hybrid scaffold system in large- and high-load-bearing osteochondral defects repair. The implants were made of medical-grade PCL (mPCL) for the bone compartment whereas fibrin glue was used for the cartilage part. Both matrices were seeded with allogenic bone marrow-derived mesenchymal cells (BMSC) and implanted in the defect (4 mm diameter x 5 mm depth) on medial femoral condyle of adult New Zealand White rabbits. Empty scaffolds were used at the control side. Cell survival was tracked via fluorescent labeling. The regeneration process was evaluated by several techniques at 3 and 6 months post-implantation. Mature trabecular bone regularly formed in the mPCL scaffold at both 3 and 6 months post-operation. Micro-Computed Tomography showed progression of mineralization from the host-tissue interface towards the inner region of the grafts. At 3 months time point, the specimens showed good cartilage repair. In contrast, the majority of 6 months specimens revealed poor remodeling and fissured integration with host cartilage while other samples could maintain good cartilage appearance. In vivo viability of the transplanted cells was demonstrated for the duration of 5 weeks. The results demonstrated that mPCL scaffold is a potential matrix for osteochondral bone regeneration and that fibrin glue does not inherit the physical properties to allow for cartilage regeneration in a large and high-load-bearing defect site.

  9. Standardized Active Middle-Ear Implant Coupling to the Short Incus Process.

    PubMed

    Mlynski, Robert; Dalhoff, Ernst; Heyd, Andreas; Wildenstein, Daniela; Rak, Kristen; Radeloff, Andreas; Hagen, Rudolf; Gummer, Anthony W; Schraven, Sebastian P

    2015-09-01

    Active middle-ear implants with floating-mass transducer (FMT) technology are used to treat mild-to-severe sensorineural hearing losses. The standard surgical approach for incus vibroplasty is a mastoidectomy and a posterior tympanotomy, crimping the FMT to the long incus process. An alternative fixation side with less surgical trauma might be the short incus process and incus body.The aim of this study was to develop and test a short incus process coupling device for its functional properties in temporal bone preparations and clinical practice. An extended antrotomy and a posterior tympanotomy were performed in 10 fresh human temporal bones. As a control for normal middle-ear function, the tympanic membrane was stimulated acoustically, and the vibration of the stapes footplate was measured using laser Doppler vibrometry. FMT-induced vibration responses of the stapes were then measured for standard attachment at the long process and for 2 types of couplers designed for attachment at the short process of the incus (SP1 and SP2 coupler). Additionally, the functional outcome in 2 patients provided with an SP2 coupler was assessed postoperatively at 2 weeks, 3 months, and then 11 months, using pure-tone audiometry, auditory thresholds for frequency-modulated (warble) tones, vibroplasty thresholds, and speech audiometry in quiet and noise. For the SP2 coupler, velocity-amplitude responses in temporal-bone preparations showed generally similar mean amplitudes as compared with the standard coupling of the FMT to the long process but with clearly increased mean amplitudes between 0.7 and 1.5 kHz and with reduced interindividual variation between 0.5 and 3 kHz. The clinical data of 2 patients with mild-to-severe sensory hearing loss showed good vibroplasty thresholds and convincing results for speech audiometry in quiet (Freiburger monosyllables at 65 dB SPL, 23 ± 31% unaided versus 83 ± 4% aided) and noise (Hochmair-Schulz-Moser-test at 65 dB SPL at 10 dB SNR, 32 ± 45

  10. Osteochondral tissue engineering with biphasic scaffold: current strategies and techniques.

    PubMed

    Shimomura, Kazunori; Moriguchi, Yu; Murawski, Christopher D; Yoshikawa, Hideki; Nakamura, Norimasa

    2014-10-01

    The management of osteoarthritis (OA) remains challenging and controversial. Although several clinical options exist for the treatment of OA, regeneration of the damaged articular cartilage has proved difficult due to the limited healing capacity. With the advancements in tissue engineering and cell-based technologies over the past decade, new therapeutic options for patients with osteochondral lesions potentially exist. This review will focus on the feasibility of tissue-engineered biphasic scaffolds, which can mimic the native osteochondral complex, for osteochondral repair and highlight the recent development of these techniques toward tissue regeneration. Moreover, basic anatomy, strategy for osteochondral repair, the design and fabrication methods of scaffolds, as well as the choice of cells, growth factor, and materials will be discussed. Specifically, we focus on the latest preclinical animal studies using large animals and clinical trials with high clinical relevance. In turn, this will facilitate an understanding of the latest trends in osteochondral repair and contribute to the future application of such clinical therapies in patients with OA.

  11. [Long-term follow-up of osteochondritis dissecans].

    PubMed

    Gudas, Rimtautas; Kunigiskis, Giedrius; Kalesinskas, Romas Jonas

    2002-01-01

    Fifty-two patients with osteochondritis dissecans lesions were evaluated after 7-25 years after excision of a partially detached (grade III) fragment or loose (grade IV) fragment from the medial femoral condyles. Average follow-up time was 17.2 (range 7-25 years). Two homogenic groups based on special inclusion criteria were formed; 31 patient was in the first and 21--in the second group. The only difference between the groups was the age; the age average in the first group was--25.6 years (range 15-35 years), and -45.2 years (range 35-55 years) in the second group. Patients were evaluated through ICRS (International Cartilage Repair Society), modified HSS and KOOS (Knee injury and osteoarthritis Outcome score) scales, and with X-rays. Evaluation with the ICRS, modified HSS and KOOS rating scales for osteochondritis dissecans revealed in 9 cases (17%) good results, 32 cases (62%)--fair, and 11 cases (21%)--failure results. Final ICRS and modified HSS evaluation showed statistically significantly better results in the younger patient group at the 21 years (p < 0.04). At an average 17.2 year follow-up X-rays and KOOS evaluation form showed initial and second-degree (according to Ahlbäck) osteoarthritis signs in the knees. The long-term results of the natural history of osteochondritis dissecans are extremely poor. Consequently, we recommend autologous osteochondral grafting for the replacement of the osteochondritis dissecans defects in the knee joint.

  12. The European Court legitimates access of Italian couples to assisted reproductive techniques and to pre-implantation genetic diagnosis.

    PubMed

    Turillazzi, Emanuela; Frati, Paola; Busardò, Francesco Paolo; Gulino, Matteo; Fineschi, Vittorio

    2015-07-01

    On 28 August 2012, the European Court of Human Rights (ECHR) issued a judgment regarding the requirements for the legitimate access of couples to assisted reproductive techniques (ART) and to pre-implantation genetic diagnosis (PGD). This judgment concerns the case of an Italian couple who found out after their first child was born with cystic fibrosis that they were healthy carriers of the disease. When the woman became pregnant again in 2010 and underwent fetal screening, it was found that the unborn child also had cystic fibrosis, whereupon she had the pregnancy terminated on medical grounds. In order to have the embryo genetically screened prior to implantation under the procedure of PGD, the couple sought to use in vitro fertilisation to have another child. Since article 1 of the Italian law strictly limits access to ART to sterile/infertile couples or those in which the man has a sexually transmissible disease, the couple appealed to the European court, raising the question of the violation of articles 8 and 14 of the European Convention on Human Rights. The applicants lodged a complaint that they were not allowed legitimate access to ART and to PGD to select an embryo not affected by the disease. The European Court affirmed that the prohibition imposed by Italian law violated article 8 of the European Convention on Human Rights. Focusing on important regulatory and legal differences among EU Nations in providing ART treatments and PGD, we derived some important similarities and differences.

  13. Fluoroquinolone use in a child associated with development of osteochondritis dissecans

    PubMed Central

    Jacobs, John C; Shea, Kevin G; Oxford, Julia Thom; Carey, James L

    2014-01-01

    Several aetiological theories have been proposed for the development of osteochondritis dissecans. Cartilage toxicity after fluoroquinolone use has been well documented in vitro. We present a case report of a 10-year-old child who underwent a prolonged 18-month course of ciprofloxacin therapy for chronic urinary tract infections. This patient later developed an osteochondritis dissecans lesion of the medial femoral condyle. We hypothesise that the fluoroquinolone therapy disrupted normal endochondral ossification, resulting in development of osteochondritis dissecans. The aetiology of osteochondritis dissecans is still unclear, and this case describes an association between fluoroquinolone use and osteochondritis dissecans development. PMID:25228675

  14. Acute Delamination of Commercially Available Decellularized Osteochondral Allograft Plugs

    PubMed Central

    Degen, Ryan M.; Tetreault, Danielle; Mahony, Greg T.; Williams, Riley J.

    2016-01-01

    Articular cartilage injuries, and corresponding surgical procedures, are occurring with increasing frequency as identified by a review of recent surgical trends. Concerns have grown in recent years regarding the longevity of results following microfracture, with a shift toward cartilage restoration procedures in recent years. This case report describes 2 cases of acute failure following the use of commercially available osteochondral allograft plugs used for the treatment of osteochondral defects of the distal femur. In both cases the chondral surface of the plug delaminated from the underlying cancellous bone, resulting in persistent pain and swelling requiring reoperation and removal of the loose fragments. Caution should be employed when considering use of these plugs for the treatment of osteochondral lesions, as similar outcomes have not been noted with other cartilage restoration techniques. PMID:27688840

  15. Tri-layered composite plug for the repair of osteochondral defects: in vivo study in sheep

    PubMed Central

    Yucekul, Altug; Ozdil, Deniz; Kutlu, Nuri Hunkar; Erdemli, Esra; Aydin, Halil Murat; Doral, Mahmut Nedim

    2017-01-01

    Cartilage defects are a source of pain, immobility, and reduced quality of life for patients who have acquired these defects through injury, wear, or disease. The avascular nature of cartilage tissue adds to the complexity of cartilage tissue repair or regeneration efforts. The known limitations of using autografts, allografts, or xenografts further add to this complexity. Autologous chondrocyte implantation or matrix-assisted chondrocyte implantation techniques attempt to introduce cultured cartilage cells to defect areas in the patient, but clinical success with these are impeded by the avascularity of cartilage tissue. Biodegradable, synthetic scaffolds capable of supporting local cells and overcoming the issue of poor vascularization would bypass the issues of current cartilage treatment options. In this study, we propose a biodegradable, tri-layered (poly(glycolic acid) mesh/poly(l-lactic acid)-colorant tidemark layer/collagen Type I and ceramic microparticle-coated poly(l-lactic acid)-poly(ϵ-caprolactone) monolith) osteochondral plug indicated for the repair of cartilage defects. The porous plug allows the continual transport of bone marrow constituents from the subchondral layer to the cartilage defect site for a more effective repair of the area. Assessment of the in vivo performance of the implant was conducted in an ovine model (n = 13). In addition to a control group (no implant), one group received the implant alone (Group A), while another group was supplemented with hyaluronic acid (0.8 mL at 10 mg/mL solution; Group B). Analyses performed on specimens from the in vivo study revealed that the implant achieves cartilage formation within 6 months. No adverse tissue reactions or other complications were reported. Our findings indicate that the porous biocompatible implant seems to be a promising treatment option for the cartilage repair. PMID:28694960

  16. Clinical outcomes following osteochondral autologous transplantation (OATS).

    PubMed

    Lahav, Amit; Burks, Robert T; Greis, Patrick E; Chapman, Andrew W; Ford, Gregory M; Fink, Barbara P

    2006-07-01

    This study evaluated the clinical outcome in 21 patients (22 knees) undergoing osteochondral autologous transplantation (OATS) in the knee over a 5-year period. Sixteen knees in 15 patients were available for follow-up at an average of 40 months after the procedure. The clinical outcome was analyzed using the IKDC and Knee and Osteoarthritis Outcome Score (KOOS) evaluation forms, a subjective questionnaire, and a clinical examination. At final follow-up, the average KOOS result for pain was 80.6 (range: 56-94), symptoms 53.6 (range: 25-71), function of activities of daily living 93.4 (range: 79-100), function of sports and recreational activities 65.3 (range: 20-100), and quality of life 51.0 (range: 6-88). The average IKDC score was 68.2. On our subjective questionnaire, the average preoperative grade given was 3.1 (range: 1-7) with an improvement at the most recent follow-up to a grade of 8.0 (range: 5-10) (P < .00001). Thirteen (86%) patients reported that they would have the surgery again if they had to make the decision a second time. Age did not correlate with subjective results on the IKDC evaluation (P = .7048) or score difference on our questionnaire (P = .9175). This procedure provides an option for articular resurfacing of the femoral condyles for focal areas of chondral defects with promising results regarding subjective improvement.

  17. Treatment of osteochondritis dissecans of the knee with a biomimetic scaffold. A prospective multicenter study

    PubMed Central

    DELCOGLIANO, MARCO; MENGHI, AMERIGO; PLACELLA, GIACOMO; SPEZIALI, ANDREA; CERULLI, GIULIANO; CARIMATI, GIULIA; PASQUALOTTO, STEFANO; BERRUTO, MASSIMO

    2014-01-01

    Purpose the aim of the present study was to evaluate the clinical outcome of the treatment of osteochondritis dissecans (OCD) of the knee with a type-I collagen-hydroxyapatite nanostructural biomimetic osteochondral scaffold. Methods twenty-three patients affected by symptomatic knee OCD of the femoral condyles, grade 3 or 4 of the International Cartilage Repair Society (ICRS) scale, underwent biomimetic scaffold implantation. The site of the defect was the medial femoral condyle in 14 patients, whereas in 9 patients the lateral femoral condyle was involved. The average size of the defects was 3.5±1.43 cm2. All patients were clinically evaluated using the ICRS subjective score, the IKDC objective score, the EQ-VAS and the Tegner Activity Score. Minimum follow-up was two years. MRI was performed at 12 and 24 months after surgery and then every 12 months thereafter. Results the ICRS subjective score improved from the baseline value of 50.93±20.6 to 76.44±18.03 at the 12 months (p<0.0005) and 82.23± 17.36 at the two-year follow-up (p<0.0005). The IKDC objective score confirmed the results. The EQ-VAS showed a significant improvement from 3.15±1.09 to 8.15±1.04 (p<0.0005) at two years of follow-up. The Tegner Activity Score improvement was statistically significant (p<0.0005). Conclusions biomimetic scaffold implantation was a good procedure for treating grade 3 and 4 OCD, in which other classic techniques are burdened by different limitations. This open one-step surgery gave promising stable results at short-term follow-up. Level of evidence Level IV, therapeutic case series. PMID:25606552

  18. Development of a Fresh Osteochondral Allograft Program Outside North America

    PubMed Central

    Tírico, Luís Eduardo Passarelli; Demange, Marco Kawamura; Santos, Luiz Augusto Ubirajara; de Rezende, Márcia Uchoa; Helito, Camilo Partezani; Gobbi, Riccardo Gomes; Pécora, José Ricardo; Croci, Alberto Tesconi; Bugbee, William Dick

    2015-01-01

    Objective To standardize and to develop a fresh osteochondral allograft protocol of procurement, processing and surgical utilization in Brazil. This study describes the steps recommended to make fresh osteochondral allografts a viable treatment option in a country without previous fresh allograft availability. Design The process involves regulatory process modification, developing and establishing procurement, and processing and surgical protocols. Results Legislation: Fresh osteochondral allografts were not feasible in Brazil until 2009 because the law prohibited preservation of fresh grafts at tissue banks. We approved an amendment that made it legal to preserve fresh grafts for 30 days from 2°C to 6°C in tissue banks. Procurement: We changed the protocol of procurement to decrease tissue contamination. All tissues were procured in an operating room. Processing: Processing of the grafts took place within 12 hours of tissue recovery. A serum-free culture media with antibiotics was developed to store the grafts. Surgeries: We have performed 8 fresh osteochondral allografts on 8 knees obtaining grafts from 5 donors. Mean preoperative International Knee Documentation Committee (IKDC) score was 31.99 ± 13.4, improving to 81.26 ± 14.7 at an average of 24 months’ follow-up. Preoperative Knee Injury and Oseoarthritis Outcome Score (KOOS) score was 46.8 ± 20.9 and rose to 85.24 ± 13.9 after 24 months. Mean preoperative Merle D’Aubigne-Postel score was 8.75 ± 2.25 rising to 16.1 ± 2.59 at 24 months’ follow-up. Conclusion To our knowledge, this is the first report of fresh osteochondral allograft transplantation in South America. We believe that this experience may be of value for physicians in countries that are trying to establish an osteochondral allograft transplant program. PMID:27375837

  19. Development of a Fresh Osteochondral Allograft Program Outside North America.

    PubMed

    Tírico, Luís Eduardo Passarelli; Demange, Marco Kawamura; Santos, Luiz Augusto Ubirajara; de Rezende, Márcia Uchoa; Helito, Camilo Partezani; Gobbi, Riccardo Gomes; Pécora, José Ricardo; Croci, Alberto Tesconi; Bugbee, William Dick

    2016-07-01

    To standardize and to develop a fresh osteochondral allograft protocol of procurement, processing and surgical utilization in Brazil. This study describes the steps recommended to make fresh osteochondral allografts a viable treatment option in a country without previous fresh allograft availability. The process involves regulatory process modification, developing and establishing procurement, and processing and surgical protocols. Legislation: Fresh osteochondral allografts were not feasible in Brazil until 2009 because the law prohibited preservation of fresh grafts at tissue banks. We approved an amendment that made it legal to preserve fresh grafts for 30 days from 2°C to 6°C in tissue banks. Procurement: We changed the protocol of procurement to decrease tissue contamination. All tissues were procured in an operating room. Processing: Processing of the grafts took place within 12 hours of tissue recovery. A serum-free culture media with antibiotics was developed to store the grafts. Surgeries: We have performed 8 fresh osteochondral allografts on 8 knees obtaining grafts from 5 donors. Mean preoperative International Knee Documentation Committee (IKDC) score was 31.99 ± 13.4, improving to 81.26 ± 14.7 at an average of 24 months' follow-up. Preoperative Knee Injury and Oseoarthritis Outcome Score (KOOS) score was 46.8 ± 20.9 and rose to 85.24 ± 13.9 after 24 months. Mean preoperative Merle D'Aubigne-Postel score was 8.75 ± 2.25 rising to 16.1 ± 2.59 at 24 months' follow-up. To our knowledge, this is the first report of fresh osteochondral allograft transplantation in South America. We believe that this experience may be of value for physicians in countries that are trying to establish an osteochondral allograft transplant program.

  20. Osteochondritis dissecans of the tarsal navicular bone: a case report.

    PubMed

    Beil, Frank Timo; Bruns, Juergen; Habermann, Christian R; Rüther, Wolfgang; Niemeier, Andreas

    2012-01-01

    Osteochondritis dissecans most often affects the convex articular surfaces of the knee, the elbow, and the ankle joints; other sites of manifestation are very rare. Here we report a case of osteochondritis dissecans of the talonavicular joint affecting the concave part of the tarsal navicular bone in a 22-year-old woman, which was successfully treated by surgery, leading to complete recovery. Early diagnosis and surgery in stages of undamaged cartilage may help to prevent disease progression and the development of disabling osteoarthritis in the physiologically heavily loaded talo-navicular joint.

  1. New implantable hearing device based on a micro-actuator that is directly coupled to the inner ear fluid.

    PubMed

    Bernhard, Hans; Stieger, Christof; Perriard, Yves

    2006-01-01

    A new hearing therapy called direct acoustical cochlear stimulation (DACS) was developed and validated in a first clinical trial with four patients. The key component of this therapy based on an implantable hearing device is a micro-actuator that is implanted in the mastoid right behind the external auditory canal of a patient. It generates vibrations that are directly coupled to the inner ear fluids and bypass therefore the outer and the middle ear. This allows treating severe to profound mixed hearing loss. The actuator transfer function has to be similar to the transfer function of a normal human middle ear to guarantee high system efficiency. A balanced armature actuator was the ideal transducer type in order to meet this requirement considering the given restrictions in size and shape.

  2. Bipolar fresh osteochondral allograft of the ankle.

    PubMed

    Giannini, Sandro; Buda, Roberto; Grigolo, Brunella; Bevoni, Roberto; Di Caprio, Francesco; Ruffilli, Alberto; Cavallo, Marco; Desando, Giovanna; Vannini, Francesca

    2010-01-01

    Severe post-traumatic ankle arthritis poses a reconstructive challenge in the young and active patient. Bipolar fresh osteochondral allograft (BFOA) may represent an intriguing alternative to arthrodesis and prosthetic replacement. The aim of this study was to describe a lateral trans-malleolar technique for BFOA, and to evaluate the results in a case series. From 2004 to 2006, 32 patients, mean age of 36.8 +/- 8.4 years, affected by ankle arthritis underwent BFOA with a mean followup of 31.2 months. The graft was prepared by specifically designed jigs, including the talus and the tibia with the medial malleolus. The host surfaces were prepared by the same jigs through a lateral approach. The graft was placed and fixed with twist-off screws. Patients were evaluated clinically and radiographically at 2, 4, and 6 month after operation, and at a minimum 24 months followup. A biopsy of the grafted areas was obtained from 7 patients at 1-year followup for histological and immunohistochemical examination. Preoperative AOFAS score was 33.1 +/- 10.9 and postoperatively 69.5 +/- 19.4 (p < 0.0005). Six failures occurred. Cartilage harvests showed hyaline-like histology with a normal collagen component but low proteoglycan presence and a disorganized structure. Samples were positive for MMP-1, MMP-13 and Capsase-3. The use of BFOA represents an intriguing alternative to arthrodesis or arthroplasty. We believe precise allograft sizing, stable fitting and fixation and delayed weightbearing were key factors for a successful outcome. Further research regarding the immunological behavior of transplanted cartilage is needed.

  3. MRI scanning in patients implanted with a round window or stapes coupled floating mass transducer of the Vibrant Soundbridge.

    PubMed

    Renninger, Daniel; Ernst, Arne; Todt, Ingo

    2016-01-01

    Conclusion MRI examinations in patients with an alternatively coupled VSB can lead to unpleasant side-effects. However, the residual hearing was not impaired, whereas the hearing performance with the VSB was decreased in one patient which could be fixed by a surgical revision. Different experiences for the VSB 503 can be expected. Objective To investigate the in vivo effects of MRI scanning on the Vibrant Soundbridge system (VSB) with an alternatively coupled Floating Mass Transducer (FMT). Method Sixty-five VSB (502) implantees were included in this study. Of them, 42 questionnaires could be evaluated with the patients' statements about their medical, otological, and general condition before, during, and after an MRI scan which was indicated for different medical reasons, despite the previous implantation of an alternatively coupled Vibrant Soundbridge System. Results In four patients (9.5%), five MRI examinations were performed. These were done for different indications (e.g. knee and shoulder joint diagnostics). During the scanning, noise and subjectively perceived distortion of the implant were described. A deterioration of the hearing gain with the VSB in place was found in one patient. A decrease of the hearing threshold was not observed.

  4. Diagnosing, planning and evaluating osteochondral ankle defects with imaging modalities

    PubMed Central

    van Bergen, Christiaan JA; Gerards, Rogier M; Opdam, Kim TM; Terra, Maaike P; Kerkhoffs, Gino MMJ

    2015-01-01

    This current concepts review outlines the role of different imaging modalities in the diagnosis, preoperative planning, and follow-up of osteochondral ankle defects. An osteochondral ankle defect involves the articular cartilage and subchondral bone (usually of the talus) and is mostly caused by an ankle supination trauma. Conventional radiographs are useful as an initial imaging tool in the diagnostic process, but have only moderate sensitivity for the detection of osteochondral defects. Computed tomography (CT) and magnetic resonance imaging (MRI) are more accurate imaging modalities. Recently, ultrasonography and single photon emission CT have been described for the evaluation of osteochondral talar defects. CT is the most valuable modality for assessing the exact location and size of bony lesions. Cartilage and subchondral bone damage can be visualized using MRI, but the defect size tends to be overestimated due to bone edema. CT with the ankle in full plantar flexion has been shown a reliable tool for preoperative planning of the surgical approach. Postoperative imaging is useful for objective assessment of repair tissue or degenerative changes of the ankle joint. Plain radiography, CT and MRI have been used in outcome studies, and different scoring systems are available. PMID:26716090

  5. Fresh osteochondral allograft transplantation for osteochondritis dissecans of the capitellum in baseball players.

    PubMed

    Mirzayan, Raffy; Lim, Michael J

    2016-11-01

    Osteochondritis dissecans (OCD) of the capitellum is a rare yet debilitating injury seen in young athletes. This is the first report in the literature describing fresh osteochondral allograft transplantation (FOCAT) to treat OCD of the capitellum. Nine male baseball players (mean age, 15.3; range, 14-18 years), with OCD of the capitellum were treated with FOCAT. There were 6 pitchers and 3 position players. A ligament-sparing, mini-open approach was used. A fresh femoral hemicondyle was used as a donor source. Of the 9 patients, 7 required 1 plug and 2 required 2 plugs. The average plug diameter was 11 mm (range, 8-18 mm). Five plugs were press fit, and 4 required additional fixation. Clinical outcomes were evaluated at a mean follow-up of 48.4 months (range, 11-90 months). Preoperative and postoperative outcome scores were calculated using the paired t test. The Mayo Elbow Performance score improved from an average 57.8 to 98.9 (P < .01). The Oxford Elbow Score improved from 22.4 to 44.8 (P < .01). The Disabilities of the Arm, Shoulder and Hand score improved from 35.2 to 5.4 (P < .01). The visual analog scale score improved from 7.8 to 0.5 (P < .01). The Kerlan-Jobe Orthopaedic Clinic Shoulder and Elbow score improved from 32.6 to 82.5 (P < .01). All patients returned to throwing and were still active in their sport or played at least 2 years of baseball before leaving the sport unrelated to the elbow. FOCAT for OCD of the capitellum in properly selected cases is a viable treatment with significant functional improvement and pain reduction in throwers. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  6. Large fresh osteochondral allografts of the knee: a systematic clinical and basic science review of the literature.

    PubMed

    De Caro, Francesca; Bisicchia, Salvatore; Amendola, Annunziato; Ding, Lei

    2015-04-01

    The aim of this study was to conduct an updated review of the literature regarding the clinical and basic science knowledge on osteochondral allograft transplantation in the knee for the treatment of large defects. According to specific criteria, 2 investigators systematically reviewed the literature for clinical and basic science reports regarding osteochondral allograft transplantation; data were independently extracted, pooled, and analyzed. Clinical and functional outcomes, International Knee Documentation Committee and Western Ontario and McMaster Universities Osteoarthritis Index scores, return to sport, quality of life, and survivorship of the grafts were assessed from the clinical articles. Regarding the basic science articles, the effects of allograft storage time, temperature, and different storage media were assessed. Eleven articles reporting on clinical data and 14 articles reporting on basic science data (animal, cell, and biomechanical studies) were selected. The articles included in the review were not homogeneous, and different outcome measures were adopted. Overall excellent results were achieved, with improvement in all objective and subjective clinical scores, a high rate of return to sport, and a survivorship rate of 89% at 5 years. When multiple plugs were implanted, posterior grafts seemed to fail. Only 1 article compared fresh versus frozen grafts, with a greater improvement in scores in the frozen group. Cellular viability and number were reduced during storage, even at low temperatures; polyphenol from green tea and arbutin and higher temperatures favorably influenced cell viability of the cartilage during storage. On the other hand, the structural properties of the extracellular matrix were not influenced by the storage at low temperatures. Integration of the graft to the host was also important, and bony integration was usually achieved; however, on the cartilage side, integration was scant or did not occur, especially in the frozen

  7. Effect of exposure environment on surface decomposition of SiC-silver ion implantation diffusion couples

    DOE PAGES

    Gerczak, Tyler J.; Zheng, Guiqui; Field, Kevin G.; ...

    2014-10-05

    SiC is a promising material for nuclear applications and is a critical component in the construction of tristructural isotropic (TRISO) fuel. A primary issue with TRISO fuel operation is the observed release of 110m Ag from intact fuel particles. The release of Ag has prompted research efforts to directly measure the transport mechanism of Ag in bulk SiC. Recent research efforts have focused primarily on Ag ion implantation designs. The effect of the thermal exposure system on the ion implantation surface has been investigated. Results indicate the utilization of a mated sample geometry and the establishment of a static thermalmore » exposure environment is critical to maintaining an intact surface for diffusion analysis. In conclusion, the nature of the implantation surface and its potential role in Ag diffusion analysis are discussed.« less

  8. Effect of exposure environment on surface decomposition of SiC-silver ion implantation diffusion couples

    SciTech Connect

    Gerczak, Tyler J.; Zheng, Guiqui; Field, Kevin G.; Allen, Todd R.

    2014-10-05

    SiC is a promising material for nuclear applications and is a critical component in the construction of tristructural isotropic (TRISO) fuel. A primary issue with TRISO fuel operation is the observed release of 110m Ag from intact fuel particles. The release of Ag has prompted research efforts to directly measure the transport mechanism of Ag in bulk SiC. Recent research efforts have focused primarily on Ag ion implantation designs. The effect of the thermal exposure system on the ion implantation surface has been investigated. Results indicate the utilization of a mated sample geometry and the establishment of a static thermal exposure environment is critical to maintaining an intact surface for diffusion analysis. In conclusion, the nature of the implantation surface and its potential role in Ag diffusion analysis are discussed.

  9. Spontaneous hyaline cartilage regeneration can be induced in an osteochondral defect created in the femoral condyle using a novel double-network hydrogel.

    PubMed

    Yokota, Masashi; Yasuda, Kazunori; Kitamura, Nobuto; Arakaki, Kazunobu; Onodera, Shin; Kurokawa, Takayuki; Gong, Jian-Ping

    2011-02-22

    Functional repair of articular osteochondral defects remains a major challenge not only in the field of knee surgery but also in tissue regeneration medicine. The purpose is to clarify whether the spontaneous hyaline cartilage regeneration can be induced in a large osteochondral defect created in the femoral condyle by means of implanting a novel double-network (DN) gel at the bottom of the defect. Twenty-five mature rabbits were used in this study. In the bilateral knees of each animal, we created an osteochondral defect having a diameter of 2.4-mm in the medial condyle. Then, in 21 rabbits, we implanted a DN gel plug into a right knee defect so that a vacant space of 1.5-mm depth (in Group I), 2.5-mm depth (in Group II), or 3.5-mm depth (in Group III) was left. In the left knee, we did not apply any treatment to the defect to obtain the control data. All the rabbits were sacrificed at 4 weeks, and the gross and histological evaluations were performed. The remaining 4 rabbits underwent the same treatment as used in Group II, and real-time PCR analysis was performed at 4 weeks. The defect in Group II was filled with a sufficient volume of the hyaline cartilage tissue rich in proteoglycan and type-2 collagen. The Wayne's gross appearance and histology scores showed that Group II was significantly greater than Group I, III, and Control (p < 0.012). The relative expression level of type-2 collagen, aggrecan, and SOX9 mRNAs was significantly greater in Group II than in the control group (p < 0.023). This study demonstrated that spontaneous hyaline cartilage regeneration can be induced in vivo in an osteochondral defect created in the femoral condyle by means of implanting the DN gel plug at the bottom of the defect so that an approximately 2-mm deep vacant space was intentionally left in the defect. This fact has prompted us to propose an innovative strategy without cell culture to repair osteochondral lesions in the femoral condyle.

  10. Inactivation of Vhl in Osteochondral Progenitor Cells Causes High Bone Mass Phenotype and Protects Against Age-Related Bone Loss in Adult Mice

    PubMed Central

    Weng, Tujun; Xie, Yangli; Huang, Junlan; Luo, Fengtao; Yi, Lingxian; He, Qifen; Chen, Di; Chen, Lin

    2014-01-01

    Previous studies have shown that disruption of von Hippel–Lindau gene (Vhl) coincides with activation of hypoxia-inducible factor α (HIFα) signaling in bone cells and plays an important role in bone development, homeostasis, and regeneration. It is known that activation of HIF1α signaling in mature osteoblasts is central to the coupling between angiogenesis and bone formation. However, the precise mechanisms responsible for the coupling between skeletal angiogenesis and osteogenesis during bone remodeling are only partially elucidated. To evaluate the role of Vhl in bone homeostasis and the coupling between vascular physiology and bone, we generated mice lacking Vhl in osteochondral progenitor cells (referred to as Vhl cKO mice) at postnatal and adult stages in a tamoxifen-inducible manner and changes in skeletal morphology were assessed by micro–computed tomography (µCT), histology, and bone histomorphometry. We found that mice with inactivation of Vhl in osteochondral progenitor cells at the postnatal stage largely phenocopied that of mice lacking Vhl in mature osteoblasts, developing striking and progressive accumulation of cancellous bone with increased microvascular density and bone formation. These were accompanied with a significant increase in osteoblast proliferation, upregulation of differentiation marker Runx2 and osteocalcin, and elevated expression of vascular endothelial growth factor (VEGF) and phosphorylation of Smad1/5/8. In addition, we found that Vhl deletion in osteochondral progenitor cells in adult bone protects mice from aging-induced bone loss. Our data suggest that the VHL-mediated signaling in osteochondral progenitor cells plays a critical role in bone remodeling at postnatal/adult stages through coupling osteogenesis and angiogenesis. © 2014 American Society for Bone and Mineral Research. PMID:23999831

  11. Inductive coupling links for lowest misalignment effects in transcutaneous implanted devices.

    PubMed

    Abbas, Saad Mutashar; Hannan, Mahammad A; Samad, Salina A; Hussain, Aini

    2014-06-01

    Use of transcutaneous inductive links is a widely known method for the wireless powering of bio-implanted devices such as implanted microsystems. The design of the coil for inductive links is generally not optimal. In this study, inductive links were used on the basis of the small loop antenna theory to reduce the effects of lateral coil misalignments on the biological human tissue model at 13.56 MHz. The tissue, which measures 60 mm×70 mm×5 mm, separates the reader and the implanted coils. The aligned coils and the lateral misalignment coils were investigated in different parametric x-distance misalignments. The optimal coil layout was developed on the basis of the layout rules presented in previous studies. Results show that the gain around the coils, which were separated by wet and dry skin, was constant and confirmed the omnidirectional radiation pattern even though the lateral misalignment between coils was smaller or greater than the implanted coil radius. This misalignment can be <4 mm or >6 mm up to 8 mm. Moreover, coil misalignments and skin condition do not affect the efficient performance of the coil.

  12. An NFC on Two-Coil WPT Link for Implantable Biomedical Sensors under Ultra-Weak Coupling.

    PubMed

    Gong, Chen; Liu, Dake; Miao, Zhidong; Wang, Wei; Li, Min

    2017-06-11

    The inductive link is widely used in implantable biomedical sensor systems to achieve near-field communication (NFC) and wireless power transfer (WPT). However, it is tough to achieve reliable NFC on an inductive WPT link when the coupling coefficient is ultra-low (0.01 typically), since the NFC signal (especially for the uplink from the in-body part to the out-body part) could be too weak to be detected. Traditional load shift keying (LSK) requires strong coupling to pass the load modulation information to the power source. Instead of using LSK, we propose a dual-carrier NFC scheme for the weak-coupled inductive link; using binary phase shift keying (BPSK) modulation, its downlink data are modulated on the power carrier (2 MHz), while its uplink data are modulated on another carrier (125 kHz). The two carriers are transferred through the same coil pair. To overcome the strong interference of the power carrier, dedicated circuits are introduced. In addition, to minimize the power transfer efficiency decrease caused by adding NFC, we optimize the inductive link circuit parameters and approach the receiver sensitivity limit. In the prototype experiments, even though the coupling coefficient is as low as 0.008, the in-body transmitter costs only 0.61 mW power carrying 10 kbps of data, and achieves a 1 × 10 - 7 bit error rate under the strong interference of WPT. This dual-carrier NFC scheme could be useful for small-sized implantable biomedical sensor applications.

  13. An NFC on Two-Coil WPT Link for Implantable Biomedical Sensors under Ultra-Weak Coupling

    PubMed Central

    Gong, Chen; Liu, Dake; Miao, Zhidong; Wang, Wei; Li, Min

    2017-01-01

    The inductive link is widely used in implantable biomedical sensor systems to achieve near-field communication (NFC) and wireless power transfer (WPT). However, it is tough to achieve reliable NFC on an inductive WPT link when the coupling coefficient is ultra-low (0.01 typically), since the NFC signal (especially for the uplink from the in-body part to the out-body part) could be too weak to be detected. Traditional load shift keying (LSK) requires strong coupling to pass the load modulation information to the power source. Instead of using LSK, we propose a dual-carrier NFC scheme for the weak-coupled inductive link; using binary phase shift keying (BPSK) modulation, its downlink data are modulated on the power carrier (2 MHz), while its uplink data are modulated on another carrier (125 kHz). The two carriers are transferred through the same coil pair. To overcome the strong interference of the power carrier, dedicated circuits are introduced. In addition, to minimize the power transfer efficiency decrease caused by adding NFC, we optimize the inductive link circuit parameters and approach the receiver sensitivity limit. In the prototype experiments, even though the coupling coefficient is as low as 0.008, the in-body transmitter costs only 0.61 mW power carrying 10 kbps of data, and achieves a 1 × 10−7 bit error rate under the strong interference of WPT. This dual-carrier NFC scheme could be useful for small-sized implantable biomedical sensor applications. PMID:28604610

  14. Effect of fluoride on the corrosion behavior of Ti and Ti6Al4V dental implants coupled with different superstructures.

    PubMed

    Anwar, Eman M; Kheiralla, Lamia S; Tammam, Riham H

    2011-06-01

    The effect of fluoride ion concentration on the corrosion behavior of Ti and Ti6Al4V implant alloys, when coupled with either metal/ceramic or all-ceramic superstructure, was examined by different electrochemical methods in artificial saliva solutions. It was concluded that increased fluoride concentration leads to a decrease in the corrosion resistance of all tested couples. The type of the superstructure also showed a significant effect on the corrosion resistance of the couple.

  15. [TREATMENT OF RECURRENT PATELLAR DISLOCATION ASSOCIATED WITH OLD OSTEOCHONDRAL FRACTURE].

    PubMed

    Dai, Zhu; You, Di; Liao, Ying; Chen, Zhiwei; Peng, Jiabin

    2016-01-01

    To explore the treatment methed of recurrent patellar dislocation associated with old osteochondral fracture and to evaluate its effectiveness. Between August 2010 and August 2014, 12 cases of recurrent patellar dislocation with old osteochondral fracture were treated. There were 4 males and 8 females with an average age of 18.3 years (range, 15-24 years). The left knee was involved in 7 cases and the right knee in 5 cases. All the patients had a history of patellar dislocation, the average interval from injury to first hospitalization was 7.6 months (range, 6-13 months). At preoperation, the range of motion (ROM) of the injured knee was (89.17 ± 13.11)degrees; the Lysholm score was 56.67 ± 18.91; the Q-angle was (17.50 ± 5.28)degrees; and tibial tuberosity-trochlear groove (TT-TG) distance was (18.33 ± 4.03) mm. The Q-angle was more than 20 degrees and TT-TG distance was more than 20 mm in 6 of 12 cases. There were 6 cases of patellar osteochondral fracture, 5 cases of lateral femoral condylar osteochondral fracture, and 1 case of patellar osteochondral fracture combined with lateral femoral condylar osteochondral fracture. After osteochondral fracture fragments were removed under arthroscope, lateral patellar retinaculum releasing and medial patellar retinaculum reefing was performed in 2 cases, medial patellofemoral ligament (MPFL) reconstruction combined with both lateral patellar retinaculum releasing and medial patellar retinaculum reefing in 4 cases, and MPFL reconstruction, lateral patellar retinaculum releasing, medial patellar retinaculum reefing, and tibial tubercle transfer in 6 cases. Results All wounds healed by first intention with no complication of infection, haematoma, skin necrosis, or bone nonunion. All patients were followed up 12-60 months with an average of 24.2 months. At 3 months after operation, all patellar dislocations were corrected; the Q-angle was (13.33 ± 1.37)degrees and the TT-TG distance was (12.17 ± 1.17) mm in 6 patients

  16. Osteochondral Lesion of the Bilateral Femoral Heads in a Young Athletic Patient

    PubMed Central

    Lee, Jung Eun; Park, Ji Seon; Cho, Yoon Je; Yoon, So Hee; Park, So Young; Jin, Wook; Lee, Kyung Ryeol

    2014-01-01

    Osteochondral lesions of the femoral head are uncommon and few studies have reported their imaging findings. Since joints are at risk of early degeneration after osteochondral damage, timely recognition is important. Osteochondral lesions of femoral head may often be necessary to differentiate from avascular necrosis. Here, we report a case of osteochondral lesions on bilateral femoral heads. This lesion manifested as subchondral cysts in initial radiographs, which led to further evaluation by computed tomography arthrography and magnetic resonance imaging, which revealed overlying cartilage defects. PMID:25469091

  17. Biomaterials/scaffolds. Design of bioactive, multiphasic PCL/collagen type I and type II-PCL-TCP/collagen composite scaffolds for functional tissue engineering of osteochondral repair tissue by using electrospinning and FDM techniques.

    PubMed

    Schumann, Detlef; Ekaputra, Andrew K; Lam, Christopher X F; Hutmacher, Dietmar W

    2007-01-01

    Current clinical therapies for traumatic or chronic injuries involving osteochondral tissue result in temporary pain reduction and filling of the defect but with biomechanically inferior repair tissue. Tissue engineering of osteochondral repair tissue using autologous cells and bioactive biomaterials has the potential to overcome the current limitations and results in native-like repair tissue with good integration capabilities. For this reason, we applied two modem biomaterial design techniques, namely, electrospinning and fused deposition modeling (FDM), to produce bioactive poly(epsilon-caprolactone)/collagen (PCL/Col) type I and type II-PCL-tri-calcium phosphate (TCP)/Col composites for precursor cell-based osteochondral repair. The application of these two design techniques (electrospinning and FDM) allowed us to specifically produce the a suitable three-dimensional (3D) environment for the cells to grow into a particular tissue (cartilage and bone) in vitro prior to in vivo implantation. We hypothesize that our new designed biomaterials, seeded with autologous bone marrow-derived precursor cells, in combination with bioreactor-stimulated cell-culture techniques can be used to produce clinically relevant osteochondral repair tissue.

  18. Osteochondral defect repair using a polyvinyl alcohol-polyacrylic acid (PVA-PAAc) hydrogel.

    PubMed

    Bichara, David A; Bodugoz-Sentruk, Hatice; Ling, Doris; Malchau, Erik; Bragdon, Charles R; Muratoglu, Orhun K

    2014-08-01

    Poly(vinyl alcohol) (PVA) hydrogels can be candidates for articular cartilage repair due to their high water content. We synthesized a PVA-poly(acrylic acid) (PAAc) hydrogel formulation and determined its ability to function as a treatment option for condylar osteochondral (OC) defects in a New Zealand white rabbit (NZWR) model for 12 weeks and 24 weeks. In addition to hydrogel OC implants, tensile bar-shaped hydrogels were also implanted subcutaneously to evaluate changes in mechanical properties as a function of in vivo duration. There were no statistically significant differences (p > 0.05) in the water content measured in the OC hydrogel implant that was harvested after 12 weeks and 24 weeks, and non-implanted controls. There were no statistically significant differences (p > 0.05) in the break stress, strain at break or modulus of the tensile bars either between groups. Histological analysis of the OC defect, synovial capsule and fibrous tissue around the tensile bars determined hydrogel biocompatibility. Twelve-week hydrogels were found to be in situ flush with the articular cartilage; meniscal tissue demonstrated an intact surface. Twenty-four week hydrogels protruded from the defect site due to lack of integration with subchondral tissue, causing fibrillation to the meniscal surface. Condylar micro-CT scans ruled out osteolysis and bone cysts of the subchondral bone, and no PVA-PAAc hydrogel contents were found in the synovial fluid. The PVA-PAAc hydrogel was determined to be fully biocompatible, maintained its properties over time, and performed well at the 12 week time point. Physical fixation of the PVA-PAAc hydrogel to the subchondral bone is required to ensure long-term performance of hydrogel plugs for OC defect repair.

  19. Customized Fabrication of Osteochondral Tissue for Articular Joint Surface Repair

    DTIC Science & Technology

    2015-09-01

    it is a disease of the cartilage, bone and surrounding soft tissue that disables 9-10% of the US population. In the US military , combat and non...cartilage – it is a disease of the cartilage, bone and surrounding soft tissue that disables 9-10% of the US population. In the US military , combat and...1 AD______________ AWARD NUMBER: W81XWH-14-1-0217 TITLE: “Customized Fabrication of Osteochondral Tissue for Articular Joint Surface Repair

  20. Recent Advances in Egypt for Treatment of Talar Osteochondral Lesions.

    PubMed

    Haleem, Amgad M; AbouSayed, Mostafa M; Gomaa, Mohammed

    2016-06-01

    Treatment of osteochondral defects (OCLs) of the talus is a challenging orthopedic surgery. Treatment of talar OCLs has evolved through the 3 "R" paradigm: reconstruction, repair, and replacement. This article highlights current state-of-the-art techniques and reviews recent advances in the literature about articular cartilage repair using various novel tissue engineering approaches, including various scaffolds, growth factors, and cell niches; which include chondrocytes and culture-expanded bone marrow-derived mesenchymal stem cells.

  1. Sol gel-derived hydroxyapatite films over porous calcium polyphosphate substrates for improved tissue engineering of osteochondral-like constructs.

    PubMed

    Lee, Whitaik David; Gawri, Rahul; Pilliar, Robert M; Stanford, William L; Kandel, Rita A

    2017-08-14

    Integration of in vitro-formed cartilage on a suitable substrate to form tissue-engineered implants for osteochondral defect repair is a considerable challenge. In healthy cartilage, a zone of calcified cartilage (ZCC) act as an intermediary for mechanical force transfer from soft to hard tissue, as well as an effective interlocking structure to better resist interfacial shear forces. We have developed biphasic constructs that consist of scaffold-free cartilage tissue grown in vitro on, and interdigitated with, porous calcium polyphosphate (CPP) substrates. However, as CPP degrades, it releases inorganic polyphosphates (polyP) that can inhibit local mineralization, thereby preventing the formation of a ZCC at the interface. Thus, we hypothesize that coating CPP substrate with a layer of hydroxyapatite (HA) might prevent or limit this polyP release. To investigate this we tested both inorganic or organic sol-gel processing methods, as a barrier coating on CPP substrate to inhibit polyP release. Both types of coating supported the formation of ZCC in direct contact with the substrate, however the ZCC appeared more continuous in the tissue formed on the organic HA sol gel coated CPP. Tissues formed on coated substrates accumulated comparable quantities of extracellular matrix and mineral, but tissues formed on organic sol-gel (OSG)-coated substrates accumulated less polyP than tissues formed on inorganic sol-gel (ISG)-coated substrates. Constructs formed with OSG-coated CPP substrates had greater interfacial shear strength than those formed with ISG-coated and non-coated substrates. These results suggest that the OSG coating method can modify the location and distribution of ZCC and can be used to improve the mechanical integrity of tissue-engineered constructs formed on porous CPP substrates. Articular cartilage interfaces with bone through a zone of calcified cartilage. This study describes a method to generate an "osteochondral-like" implant that mimics this

  2. 3D printing of novel osteochondral scaffolds with graded microstructure.

    PubMed

    Nowicki, Margaret A; Castro, Nathan J; Plesniak, Michael W; Zhang, Lijie Grace

    2016-10-14

    Osteochondral tissue has a complex graded structure where biological, physiological, and mechanical properties vary significantly over the full thickness spanning from the subchondral bone region beneath the joint surface to the hyaline cartilage region at the joint surface. This presents a significant challenge for tissue-engineered structures addressing osteochondral defects. Fused deposition modeling (FDM) 3D bioprinters present a unique solution to this problem. The objective of this study is to use FDM-based 3D bioprinting and nanocrystalline hydroxyapatite for improved bone marrow human mesenchymal stem cell (hMSC) adhesion, growth, and osteochondral differentiation. FDM printing parameters can be tuned through computer aided design and computer numerical control software to manipulate scaffold geometries in ways that are beneficial to mechanical performance without hindering cellular behavior. Additionally, the ability to fine-tune 3D printed scaffolds increases further through our investment casting procedure which facilitates the inclusion of nanoparticles with biochemical factors to further elicit desired hMSC differentiation. For this study, FDM was used to print investment-casting molds innovatively designed with varied pore distribution over the full thickness of the scaffold. The mechanical and biological impacts of the varied pore distributions were compared and evaluated to determine the benefits of this physical manipulation. The results indicate that both mechanical properties and cell performance improve in the graded pore structures when compared to homogeneously distributed porous and non-porous structures. Differentiation results indicated successful osteogenic and chondrogenic manipulation in engineered scaffolds.

  3. 3D printing of novel osteochondral scaffolds with graded microstructure

    NASA Astrophysics Data System (ADS)

    Nowicki, Margaret A.; Castro, Nathan J.; Plesniak, Michael W.; Zhang, Lijie Grace

    2016-10-01

    Osteochondral tissue has a complex graded structure where biological, physiological, and mechanical properties vary significantly over the full thickness spanning from the subchondral bone region beneath the joint surface to the hyaline cartilage region at the joint surface. This presents a significant challenge for tissue-engineered structures addressing osteochondral defects. Fused deposition modeling (FDM) 3D bioprinters present a unique solution to this problem. The objective of this study is to use FDM-based 3D bioprinting and nanocrystalline hydroxyapatite for improved bone marrow human mesenchymal stem cell (hMSC) adhesion, growth, and osteochondral differentiation. FDM printing parameters can be tuned through computer aided design and computer numerical control software to manipulate scaffold geometries in ways that are beneficial to mechanical performance without hindering cellular behavior. Additionally, the ability to fine-tune 3D printed scaffolds increases further through our investment casting procedure which facilitates the inclusion of nanoparticles with biochemical factors to further elicit desired hMSC differentiation. For this study, FDM was used to print investment-casting molds innovatively designed with varied pore distribution over the full thickness of the scaffold. The mechanical and biological impacts of the varied pore distributions were compared and evaluated to determine the benefits of this physical manipulation. The results indicate that both mechanical properties and cell performance improve in the graded pore structures when compared to homogeneously distributed porous and non-porous structures. Differentiation results indicated successful osteogenic and chondrogenic manipulation in engineered scaffolds.

  4. Osteochondral Interface Tissue Engineering Using Macroscopic Gradients of Bioactive Signals

    PubMed Central

    Dormer, Nathan H.; Singh, Milind; Wang, Limin; Berkland, Cory J.; Detamore, Michael S.

    2013-01-01

    Continuous gradients exist at osteochondral interfaces, which may be engineered by applying spatially patterned gradients of biological cues. In the present study, a protein-loaded microsphere-based scaffold fabrication strategy was applied to achieve spatially and temporally controlled delivery of bioactive signals in three-dimensional (3D) tissue engineering scaffolds. Bone morphogenetic protein-2 and transforming growth factor-β1-loaded poly(d,llactic- co-glycolic acid) microspheres were utilized with a gradient scaffold fabrication technology to produce microsphere-based scaffolds containing opposing gradients of these signals. Constructs were then seeded with human bone marrow stromal cells (hBMSCs) or human umbilical cord mesenchymal stromal cells (hUCMSCs), and osteochondral tissue regeneration was assessed in gradient scaffolds and compared to multiple control groups. Following a 6-week cell culture, the gradient scaffolds produced regionalized extracellular matrix, and outperformed the blank control scaffolds in cell number, glycosaminoglycan production, collagen content, alkaline phosphatase activity, and in some instances, gene expression of major osteogenic and chondrogenic markers. These results suggest that engineered signal gradients may be beneficial for osteochondral tissue engineering. PMID:20379780

  5. Osteochondral lesions in children with juvenile idiopathic arthritis.

    PubMed

    Kröger, Liisa; Piippo-Savolainen, Eija; Tyrväinen, Erja; Penttilä, Pekko; Kröger, Heikki

    2013-05-01

    Joint pain and swelling are typical symptoms in children with juvenile idiopathic arthritis (JIA) and these are often related to inflammation of the joint. Juvenile osteochondritis dissecans (JOCD), that is separation of a bone-cartilage segment from the articular surface, can manifest with similar symptoms. We studied thirteen cases of osteochondritis dissecans lesions (OCD) in children with JIA. There were nine girls and four boys with a mean age of 6.5 (2-12) years at the time of diagnosis of JIA. Mean time between diagnosis of JIA and manifestation of OCD was 5.5 (1-11) years. Indications for MRI were the presence of pain or discomfort in the joint, despite otherwise effective treatment, with no evidence from ultrasound examination of any obvious signs of active inflammation. The most common location of osteochondral lesion was the knee, although the ankle joint was affected in one case. Five patients had lesions in both knees. Operative treatment was needed in eight cases (joints). Pain, and minor dysfunction of the joint are common complaints of children suffering from JIA. Earlier research has discounted the possibility of children who were not athletes presenting with this condition. However, this study demonstrates that these lesions also seem to be relatively common in patients with JIA. When there is no sign of inflammation, the possibility of OCD must therefore be considered in these children.

  6. Improvement in magnetic field immunity of externally-coupled transcutaneous energy transmission system for a totally implantable artificial heart.

    PubMed

    Yamamoto, Takahiko; Koshiji, Kohji; Homma, Akihiko; Tatsumi, Eisuke; Taenaka, Yoshiyuki

    2008-01-01

    Transcutaneous energy transmission (TET) that uses electromagnetic induction between the external and internal coils of a transformer is the most promising method to supply driving energy to a totally implantable artificial heart without invasion. Induction-heating (IH) cookers generate magnetic flux, and if a cooker is operated near a transcutaneous transformer, the magnetic flux generated will link with the external and internal coils of the transcutaneous transformer. This will affect the performance of the TET and the artificial heart system. Hence, it is necessary to improve the magnetic field immunity of the TET system. During operation of the system, if the transcutaneous transformer is in close proximity to an IH cooker, the electric power generated by the cooker and coupled to the transformer can drive the artificial heart system. To prevent this coupling, the external coil was shielded with a conductive shield that had a slit in it. This reduces the coupling between the transformer and the magnetic field generated by the induction cooker. However, the temperature of the shield increased due to heating by eddy currents. The temperature of the shield can be reduced by separating the IH cooker and the shield.

  7. Short-term clinical results of arthroscopic osteochondral fixation for elbow osteochondritis dissecans in teenaged baseball players.

    PubMed

    Takeba, Jun; Takahashi, Toshiaki; Watanabe, Seiji; Imai, Hiroshi; Kikuchi, Satoshi; Umakoshi, Kensuke; Matsumoto, Hironori; Ohshita, Muneaki; Miura, Hiromasa; Aibiki, Mayuki

    2015-11-01

    Reports regarding arthroscopic fixation of the osteochondral fragments for elbow osteochondritis dissecans (OCD) are few. This study assessed the clinical outcomes of arthroscopic fixation of unstable osteochondral fragments by using absorbable pins over a postoperative period of at least 1 year. The patients were 13 adolescent baseball players with a mean age of 14 years (range, 12-16 years) who underwent OCD of primary lesions at International Cartilage Repair Society grades III and IV. The patients were evaluated by using validated outcome measures at a mean follow-up period of 24 months (range, 12-50 months). The mean (standard deviation) score in the disability/symptom section of the Disabilities of the Arm, Shoulder, and Hand improved from 12.4 (6.0) before the surgery to 0.5 (1.2) after the surgery, and the sports section improved from 74.5 (25.4) to 1.4 (5.2). The mean (standard deviation) extension improved from -11° (10.8) to -2° (3.9; P < .001). The mean (SD) flexion improved from 129° (11.6) to 137° (5.6; P = .040). All patients were able to resume playing baseball, and 9 (69%) resumed playing at the same position as before their injuries. The clinical results of arthroscopic osteochondral fragment fixation in the teenaged baseball players with elbow OCD, albeit obtained over only a short period, were favorable. This arthroscopic treatment enables repair of lesions and is considered appropriate for unstable OCD during the adolescent growth spurt. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  8. Biomechanical characteristics of osteochondral defects of the humeral capitellum.

    PubMed

    Mihata, Teruhisa; Quigley, Ryan; Robicheaux, Grant; McGarry, Michelle H; Neo, Masashi; Lee, Thay Q

    2013-08-01

    The repetitive, excessive compression forces in the radiocapitellar joint caused by elbow valgus stresses during throwing motions can result in osteochondritis dissecans (OCD) of the humeral capitellum in adolescent athletes. To assess the effect of elbow valgus torque on contact pressure in the radiocapitellar joint and that of central and lateral capitellar osteochondral defects on radiocapitellar joint contact pressure, elbow valgus laxity, and ulnar collateral ligament (UCL) strain. Controlled laboratory study. In 8 matched pairs of fresh-frozen cadaveric upper limbs, lateral osteochondral defects of the humeral capitellum (5-, 10-, 15-, and 20-mm diameters) were evaluated in one side, and central defects were evaluated in the contralateral side. Radiocapitellar joint contact pressure, elbow valgus laxity, and UCL strain were all measured with and without 2 N·m of valgus torque at 30°, 60°, and 90° of elbow flexion in neutral forearm rotation. Applying valgus torque increased contact pressure in radiocapitellar joints with intact or damaged capitula. Contact pressure in joints with 15-mm (90° of elbow flexion) and 20-mm (60° and 90° of elbow flexion) lateral capitellar defects was greater than that in joints with intact capitula. Radiocapitellar contact pressure was greater with a 20-mm lateral capitellar defect than in the same-sized central defect at 60° and 90° of elbow flexion. In both central and lateral defect groups, elbow valgus laxity increased as the size of the capitellar defect increased, and UCL strain remained unchanged regardless of the size of the capitellar defect. Elbow valgus torque increases contact pressure in the radiocapitellar joint. Capitellar osteochondral defects increase elbow valgus laxity and contact pressure without increasing UCL strain. When valgus torque is applied, contact pressure in the radiocapitellar joint is greater with a lateral defect than with a central defect. Adolescent baseball players with capitellar OCD

  9. Arthroscopically assisted autologous osteochondral transplantation for osteochondral lesions of the talar dome: an MRI and clinical follow-up study.

    PubMed

    Assenmacher, J A; Kelikian, A S; Gottlob, C; Kodros, S

    2001-07-01

    Osteochondral Lesions of the Talar Dome (OLT) are common problems encountered in orthopedics. Although the etiology remains uncertain, a myriad of treatment options exists. The authors describe arthroscopically assisted autologous osteochondral graft (OCG) transplantation procedures in the treatment of unstable OLTs in nine patients. The patients underwent standard preoperative MRI examination to assess fragment stability (using De Smet criteria for stability). Intraoperative arthroscopy was used to correlate the preoperative MRI assessment (using Cheng/Ferkel grading). After transplantation procedures, MRI (using De Smet criteria for stability) assessed graft incorporation for stability at an average of 9.3 months after the procedure. Preoperative MRI correlated highly with arthroscopic findings of OLT instability (sensitivity = 1.0). This has been demonstrated in the current orthopedic literature. The post transplantation MRI demonstrated stable graft osteointegration by De Smet criteria in all patients. Postoperative visual analogue pain scales showed significant improvement from preoperative assessment. Postoperative AOFAS Ankle-Hindfoot scores averaged 80.2 (S.D. +/- 18.9). Our favorable early results and those of other authors using similar techniques may validate OCG transplantation as a viable alternative for treating unstable osteochondral defects in the talus that are refractive to more commonly used surgical techniques.

  10. Review of the biomechanics and biotribology of osteochondral grafts used for surgical interventions in the knee

    PubMed Central

    Bowland, Philippa; Ingham, E; Jennings, Louise; Fisher, John

    2015-01-01

    A review of research undertaken to evaluate the biomechanical stability and biotribological behaviour of osteochondral grafts in the knee joint and a brief discussion of areas requiring further improvement in future studies are presented. The review takes into consideration osteochondral autografts, allografts, tissue engineered constructs and synthetic and biological scaffolds. PMID:26614801

  11. Solcoseryl, a tissue respiration stimulating agent, significantly enhances the effect of capacitively coupled electric field on the promotion of bone formation around dental implants.

    PubMed

    Ochi, Morio; Wang, Pao-Li; Ohura, Kiyoshi; Takashima, Shigenori; Kagami, Hiroyuki; Hirose, Yukito; Kaku, Tohru; Sakaguchi, Kunihiko

    2003-06-01

    In the present study we examined the combined effect of application of a capacitively coupled electric field (CCEF) and the tissue respiration stimulating agent, Solcoseryl, on the promotion of bone formation around dental implants histologically and mechanically. After a dental implant was inserted into each femur of Japanese white rabbits, Solcoseryl (2 ml/kg) was administered intravenously in the ear vein and a CCEF was applied for 4 h per day for 14 days. The degree of bone formation on microscopic observation, bone contact ratio, bone surface area ratio, and the level of removal torque of the implant in the Solcoseryl- and CCEF-treated group were significantly higher than the respective value in the control group, which had not been treated with Solcoseryl nor CCEF. Thus, the combination of CCEF stimulation and Solcoseryl effectively promoted the formation of new bone. It is suggested that the clinical use of a combination of CCEF stimulation and Solcoseryl for dental implants promotes osseointegration.

  12. Measurement and analysis of channel attenuation characteristics for an implantable galvanic coupling human-body communication.

    PubMed

    Zhang, Shuang; Pun, Sio Hang; Mak, Peng Un; Qin, Yu-Ping; Liu, Yi-He; Vai, Mang I

    2016-11-14

    In this study, an experiment was designed to verify the low power consumption of galvanic coupling human-body communication. A silver electrode (silver content: 99%) is placed in a pig leg and a sine wave signal with the power of 0 dBm is input. Compared with radio frequency communication and antenna transmission communication, attenuation is reduced by approximately 10 to 15 dB, so channel characteristics are highly improved.

  13. Subchondral nacre implant in the articular zone of the sheep's knee: a pilot study.

    PubMed

    Rousseau, Marthe; Delattre, Olivier; Gillet, Pierre; Lopez, Evelyne

    2012-01-01

    The present study was designed to analyze the intra-articular behaviour of nacre, when implanted in the subchondral bone area in the sheep knee. We implanted nacre blocks in sheep's trochlea by replacing the half of the femoral trochlea (nacre group). For comparison we used complete cartilage resection (resection group) down to the subchondral bone. In the "nacre group", implants were well tolerated without any synovial inflammation. In addition, we observed centripetal regrowth of new cartilage after 3 months. In the "resection group", no chondral regrowth was observed, but, in contrast, a thin layer of fibrous tissue was formed. After 6 months, a new tissue covered the nacre implant formed by an osteochondral regrowth. Nacre, as a subchondral implant, exerts benefic potential for osteochondral repair.

  14. Implanted, inductively-coupled, radiofrequency coils fabricated on flexible polymeric material: Application to in vivo rat brain MRI at 7 T

    NASA Astrophysics Data System (ADS)

    Ginefri, J.-C.; Rubin, A.; Tatoulian, M.; Woytasik, M.; Boumezbeur, F.; Djemaï, B.; Poirier-Quinot, M.; Lethimonnier, F.; Darrasse, L.; Dufour-Gergam, E.

    2012-11-01

    Combined with high-field MRI scanners, small implanted coils allow for high resolution imaging with locally improved SNR, as compared to external coils. Small flexible implantable coils dedicated to in vivo MRI of the rat brain at 7 T were developed. Based on the Multi-turn Transmission Line Resonator design, they were fabricated with a Teflon substrate using copper micromolding process and a specific metal-polymer adhesion treatment. The implanted coils were made biocompatible by PolyDimethylSiloxane (PDMS) encapsulation. The use of low loss tangent material achieves low dielectric losses within the substrate and the use of the PDMS layer reduces the parasitic coupling with the surrounding media. An implanted coil was implemented in a 7 T MRI system using inductive coupling and a dedicated external pick-up coil for signal transmission. In vivo images of the rat brain acquired with in plane resolution of (150 μm)2 thanks to the implanted coil revealed high SNR near the coil, allowing for the visualization of fine cerebral structures.

  15. Coronoid reconstruction using osteochondral grafts: a biomechanical study.

    PubMed

    Bellato, Enrico; Kim, Youngbok; Fitzsimmons, James S; Berglund, Lawrence J; Hooke, Alexander W; Bachman, Daniel R; O'Driscoll, Shawn W

    2017-07-19

    The purposes of this study were to test the hypothesis that coronoid deficiency in the setting of posteromedial rotatory instability (PMRI) must be reconstructed to restore articular contact pressures to normal and to compare 3 different osteochondral grafts for this purpose. After creation of a anteromedial fracture, six cadaveric elbows were tested under gravity varus stress using a custom-made machine designed to simulate muscle loads and to passively flex the elbow. Mean articular surface contact pressure data were collected and processed using TekScan sensors and software. After testing of the intact specimen (intact condition), a PMRI injury was created (PMRI condition). Testing was repeated after reconstruction of the lateral collateral ligament (LCL) (LCL-only condition), followed by reconstruction of the coronoid with 3 different osteochondral graft techniques (reconstructed conditions). Contact pressure was consistently significantly higher in the PMRI elbow compared with the intact, LCL-only, and reconstructed conditions (P < .006). The LCL-only elbow contact pressure was significantly higher than that of the intact and reconstructed conditions from 5° to 55° of flexion (P = .018). The contact pressure of the intact elbow was never significantly different from that of the reconstructed elbow, except at 5° of flexion (P ≤ .008). No significant difference was detected between each of the reconstructed techniques (P ≥ .15). However, the annular surface of the radial head was the only graft that yielded contact pressures not significantly different from normal at any flexion angle. Isolated reconstruction of the LCL did not restore native articular surface contact pressure, and reconstruction of the coronoid using osteochondral graft was necessary. There was no difference in contact pressures among the 3 coronoid reconstruction techniques. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier

  16. Hydrogels for osteochondral repair based on photocrosslinkable carbamate dendrimers.

    PubMed

    Degoricija, Lovorka; Bansal, Prashant N; Söntjens, Serge H M; Joshi, Neel S; Takahashi, Masaya; Snyder, Brian; Grinstaff, Mark W

    2008-10-01

    First generation, photocrosslinkable dendrimers consisting of natural metabolites (i.e., succinic acid, glycerol, and beta-alanine) and nonimmunogenic poly(ethylene glycol) (PEG) were synthesized divergently in high yields using ester and carbamate forming reactions. Aqueous solutions of these dendrimers were photocrosslinked with an eosin-based photoinitiator to afford hydrogels. The hydrogels displayed a range of mechanical properties based on their structure, generation size, and concentration in solution. All of the hydrogels showed minimal swelling characteristics. The dendrimer solutions were then photocrosslinked in situ in an ex vivo rabbit osteochondral defect (3 mm diameter and 10 mm depth), and the resulting hydrogels were subjected to physiologically relevant dynamic loads. Magnetic resonance imaging (MRI) showed the hydrogels to be fixated in the defect site after the repetitive loading regimen. The ([G1]-PGLBA-MA) 2-PEG hydrogel was chosen for the 6 month pilot in vivo rabbit study because this hydrogel scaffold could be prepared at low polymer weight (10 wt %) and possessed the largest compressive modulus of the 10% formulations, a low swelling ratio, and contained carbamate linkages, which are more hydrolytically stable than the ester linkages. The hydrogel-treated osteochondral defects showed good attachment in the defect site and histological analysis showed the presence of collagen II and glycosaminoglycans (GAGs) in the treated defects. By contrast, the contralateral unfilled defects showed poor healing and negligible GAG or collagen II production. Good mechanical properties, low swelling, good attachment to the defect site, and positive in vivo results illustrate the potential of these dendrimer-based hydrogels as scaffolds for osteochondral defect repair.

  17. Technique: Osteochondral Grafting of Capitate Chondrosis in PRC

    PubMed Central

    Tang, Peter; Imbriglia, Joseph E.

    2013-01-01

    Background Proximal row carpectomy (PRC) is a useful treatment option for wrist arthritis, but the operation is contraindicated when there is arthritis of the capitate head. We describe a technique that involves resurfacing of a capitate that has focal chondrosis, using an osteochondral graft harvested from the resected carpal bones. Materials and Methods PRC patients who had a focal area of capitate chondrosis underwent osteochondral grafting of the capitate. Pre- and postoperative pain level, employment status, motion, grip strength, and Modified Mayo Wrist Scores (MMWS) were assessed. Postoperative Disability of the Arm, Shoulder, and Hand (DASH) scores were also calculated. Description of Technique The articular surface of the capitate is assessed for need for grafting. The proximal row is resected with the lunate removed intact. The arthritic area is prepared. The graft is taken from the lunate and placed in the prepared site of the capitate. Results Eight patients (average age of 53 years) were followed for 18 months. Pain: Preoperatively, moderate to severe in 7 patients; postoperatively, mild to no pain in 7 patients. Motion: Preoperative, 84° (74% of the contralateral side); postoperative 75° (66%). Grip Strength: Preoperative, 29 kg (62%); postoperative, 34 kg (71%). Mayo Wrist Score: Preoperative, 51 (poor); postoperative, 68 (fair). Average postoperative DASH score was 19.5. Follow-up radiographs showed that 75% of patients had mild to no degeneration. Conclusions Osteochondral grafting in PRC offers satisfactory results in terms of pain relief, return to work, motion, and grip strength. Level of Evidence Therapeutic IV, Case series PMID:24436818

  18. Osteochondral destruction in pigmented villonodular synovitis during the clinical course.

    PubMed

    Nishida, Yoshihiro; Tsukushi, Satoshi; Nakashima, Hiroatsu; Sugiura, Hideshi; Yamada, Yoshihisa; Urakawa, Hiroshi; Arai, Eisuke; Ishiguro, Naoki

    2012-02-01

    In pigmented villonodular synovitis (PVNS), some cases recur and progress to osteochondral destruction. The aim of our study was to clarify the occurrence of osteochondral destruction according to the location of PVNS during the clinical course. Seventy-two patients with PVNS (43 female, 29 male) with a mean age of 40 years (range 3-87 yrs) had been referred to our institutions. Factors influencing the occurrence of osteochondral destruction were investigated. Mean followup was 60 months (range 12-190 mo). Adjacent bone change occurred in 24 (42%) of 57 patients, who were evaluated at the time of the first consultation. Eight (89%) of 9 patients with hip lesions initially had bone lesions, significantly more frequently than those with other lesions (p = 0.038). Duration of symptoms was significantly correlated with the occurrence of bone lesions in diffuse knee lesions (p = 0.005). During followup, patients with location in the knee had a significantly higher incidence of osteoarthritic change (73%) compared to those with foot and ankle involvement (p = 0.027). Re-operation was more frequently required for knee lesions due to the high recurrence rate (32%). Patients who required re-operation had significantly more marked osteoarthritic change in knees (p = 0.001) during followup than those who did not. For PVNS arising in knees, repeated recurrences followed by re-operation resulted in the progression of osteoarthritic change. PVNS arising in hips, feet, and ankles developed bone lesions initially, probably due to the limited volume of these joints. The indications for re-operation for recurrent knee lesions require careful consideration regarding progression of osteoarthritic change.

  19. The "LIFT" lesion: lateral inverted osteochondral fracture of the talus.

    PubMed

    Dunlap, Bradley J; Ferkel, Richard D; Applegate, Gregory R

    2013-11-01

    The purpose of this study was to assess a series of lateral inverted osteochondral fractures of the talus. Over a 17-year period, 10 patients with an acute lateral inverted osteochondral fracture of the talus after an inversion injury to the ankle were identified. Diagnosis was made by physical examination, radiographs, magnetic resonance imaging, and/or computed tomography scan. Arthroscopy was initially performed on all patients. All patients had an inverted osteochondral fragment. In 8 of 10 patients the fragment was reattached in an open manner in conjunction with lateral ligament reefing. The fragment was excised in 2 patients. The mean age of the patients was 17.2 years. They were evaluated with the Single Assessment Numeric Evaluation, American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scale, modified Weber score, Berndt and Harty score, and Short Form 36 version 2 score. Physical and radiographic examination was also performed. The mean time to follow-up was 112.3 months (9.3 years). The mean American Orthopaedic Foot and Ankle Society score improved from 18.9 preoperatively to 86.9 postoperatively (P ≤ .0001). The mean Single Assessment Numeric Evaluation and modified Weber scores were 81.6 and 81.5, respectively. On the Berndt and Harty scale, 6 patients had a good to excellent rating; 3, fair; and 1, poor. The mean Short Form 36 version 2 scores corresponded to national averages for healthy populations. Mean loss of motion for dorsiflexion and plantarflexion was 6.8° and 3.0°, respectively, when compared with the contralateral side. All patients showed some osteophyte formation on follow-up radiographs. An inverted osteochondral fracture of the lateral talus (lateral, inverted, fracture, talus [LIFT lesion]) can occur after a twisting injury to the ankle. Clinical suspicion should be high, especially in the younger athlete. This injury can be successfully managed with a combined arthroscopic and open approach. Level IV, therapeutic case

  20. Knee hemarthros secondary to osteochondritis dissecans (König disease).

    PubMed

    Guillén Astete, Carlos; Alva García, Patricia; Carpena Zafrilla, Maria; Medina Quiñones, Carmen

    2015-01-01

    A case is presented of a hemarthrosis associated with osteochondritis dissecans in a young man who arrived in the Emergency unit due to tender and swelling of his right knee one hour after a slightly rotational gesture of the lower limb. Many years before the patient suffered a sports injury in the same knee, but it was never assessed. Radiography studies showed bone fragments inside the synovial capsule, and the joint aspiration was compatible with hemarthrosis. A review of the available information of this uncommon condition is also presented.

  1. Sports activity after osteochondral transplantation of the talus.

    PubMed

    Paul, Jochen; Sagstetter, Michael; Lämmle, Lena; Spang, Jeffrey; El-Azab, Hosam; Imhoff, Andreas B; Hinterwimmer, Stefan

    2012-04-01

    There are limited data regarding activity after osteochondral transplantation of the talus in orthopaedic publications. Osteochondral transplantation of the talus is a clinically successful treatment and enables patients to pursue regular and ongoing recreational sporting activities. Case series; Level of evidence, 4. One hundred thirty-one patients were retrospectively analyzed to determine their sporting and recreational activities at an average of 60 ± 28.4 months postoperatively (range, 24-141 months). The clinical evaluation included the Tegner activity scale, the Activity Rating Scale (ARS), and a visual analog scale (VAS) for pain. The VAS illustrated significant preoperative to postoperative improvements (6.3 to 2.7; P < .001). Regarding sporting activity, 96.9% of the patients were engaged in sports during their lifetimes compared with 83.8% the year before surgery and 89.3% at the time of survey. The Tegner score dropped from 5.9 preoperatively to 5.0 after surgery (P = .001), and the ARS decreased from 8.9 preoperatively to 6.8 postoperatively (P = .003). The sports frequency and the duration of activities did not significantly change after surgery: 1.7 ± 2.0 (range, 0-8; P = .053) and 4.2 ± 3.8 hours (range, 0-30 hours; P = .052), respectively. The number of actual reported different sports disciplines was unchanged in comparison to the year before surgery (3.7 ± 2.9; range, 0-12). The top 10 cited sports activities did not change for the lifetime, preoperative, and postoperative periods but illustrated an altered order. Although the overall satisfaction with the surgery was good, 15% of our patients were only partially satisfied, and 14% were not satisfied with the procedure. Patients engage in fewer, less frequent sporting activities when a symptomatic osteochondral lesion (OCL) at the talus is present. Talar osteochondral transplantation shows good clinical midterm results and allows patients to return to sporting activity. However, we found

  2. Perilesional changes of focal osteochondral defects in an ovine model and their relevance to human osteochondral injuries.

    PubMed

    Hepp, P; Osterhoff, G; Niederhagen, M; Marquass, B; Aigner, T; Bader, A; Josten, C; Schulz, R

    2009-08-01

    Perilesional changes of chronic focal osteochondral defects were assessed in the knees of 23 sheep. An osteochondral defect was created in the main load-bearing region of the medial condyle of the knees in a controlled, standardised manner. The perilesional cartilage was evaluated macroscopically and biopsies were taken at the time of production of the defect (T0), during a second operation one month later (T1), and after killing animals at three (T3; n = 8), four (T4; n = 8), and seven (T7; n = 8) months. All the samples were histologically assessed by the International Cartilage Repair Society grading system and Mankin histological scores. Biopsies were taken from human patients (n = 10) with chronic articular cartilage lesions and compared with the ovine specimens. The ovine perilesional cartilage presented with macroscopic and histological signs of degeneration. At T1 the International Cartilage Repair Society 'Subchondral Bone' score decreased from a mean of 3.0 (SD 0) to a mean of 1.9 (SD 0.3) and the 'Matrix' score from a mean of 3.0 (SD 0) to a mean of 2.5 (SD 0.5). This progressed further at T3, with the International Cartilage Repair Society 'Surface' grading, the 'Matrix' grading, 'Cell Distribution' and 'Cell Viability' grading further decreasing and the Mankin score rising from a mean of 1.3 (SD 1.4) to a mean of 5.1 (SD 1.6). Human biopsies achieved Mankin grading of a mean of 4.2 (SD 1.6) and were comparable with the ovine histology at T1 and T3. The perilesional cartilage in the animal model became chronic at one month and its histological appearance may be considered comparable with that seen in human osteochondral defects after trauma.

  3. Bone marrow aspiration concentrate and platelet rich plasma for osteochondral repair in a porcine osteochondral defect model.

    PubMed

    Betsch, Marcel; Schneppendahl, Johannes; Thuns, Simon; Herten, Monika; Sager, Martin; Jungbluth, Pascal; Hakimi, Mohssen; Wild, Michael

    2013-01-01

    Bone marrow aspiration concentrate (BMAC) may possess a high potency for cartilage and osseous defect healing because it contains stem cells and multiple growth factors. Alternatively, platelet rich plasma (PRP), which contains a cocktail of multiple growth factors released from enriched activated thrombocytes may potentially stimulate the mesenchymal stem cells (MSCs) in bone marrow to proliferate and differentiate. A critical size osteochondral defect (10×6 mm) in both medial femoral condyles was created in 14 Goettinger mini-pigs. All animals were randomized into the following four groups: biphasic scaffold alone (TRUFIT BGS, Smith & Nephew, USA), scaffold with PRP, scaffold with BMAC and scaffold in combination with BMAC and PRP. After 26 weeks all animals were euthanized and histological slides were cut, stained and evaluated using a histological score and immunohistochemistry. The thrombocyte number was significantly increased (p = 0.049) in PRP compared to whole blood. In addition the concentration of the measured growth factors in PRP such as BMP-2, BMP-7, VEGF, TGF-β1 and PDGF were significantly increased when compared to whole blood (p<0.05). In the defects of the therapy groups areas of chondrogenic tissue were present, which stained blue with toluidine blue and positively for collagen type II. Adding BMAC or PRP in a biphasic scaffold led to a significant improvement of the histological score compared to the control group, but the combination of BMAC and PRP did not further enhance the histological score. The clinical application of BMAC or PRP in osteochondral defect healing is attractive because of their autologous origin and cost-effectiveness. Adding either PRP or BMAC to a biphasic scaffold led to a significantly better healing of osteochondral defects compared with the control group. However, the combination of both therapies did not further enhance healing.

  4. Bone Marrow Aspiration Concentrate and Platelet Rich Plasma for Osteochondral Repair in a Porcine Osteochondral Defect Model

    PubMed Central

    Betsch, Marcel; Schneppendahl, Johannes; Thuns, Simon; Herten, Monika; Sager, Martin; Jungbluth, Pascal; Hakimi, Mohssen; Wild, Michael

    2013-01-01

    Background Bone marrow aspiration concentrate (BMAC) may possess a high potency for cartilage and osseous defect healing because it contains stem cells and multiple growth factors. Alternatively, platelet rich plasma (PRP), which contains a cocktail of multiple growth factors released from enriched activated thrombocytes may potentially stimulate the mesenchymal stem cells (MSCs) in bone marrow to proliferate and differentiate. Methods A critical size osteochondral defect (10×6 mm) in both medial femoral condyles was created in 14 Goettinger mini-pigs. All animals were randomized into the following four groups: biphasic scaffold alone (TRUFIT BGS, Smith & Nephew, USA), scaffold with PRP, scaffold with BMAC and scaffold in combination with BMAC and PRP. After 26 weeks all animals were euthanized and histological slides were cut, stained and evaluated using a histological score and immunohistochemistry. Results The thrombocyte number was significantly increased (p = 0.049) in PRP compared to whole blood. In addition the concentration of the measured growth factors in PRP such as BMP-2, BMP-7, VEGF, TGF-β1 and PDGF were significantly increased when compared to whole blood (p<0.05). In the defects of the therapy groups areas of chondrogenic tissue were present, which stained blue with toluidine blue and positively for collagen type II. Adding BMAC or PRP in a biphasic scaffold led to a significant improvement of the histological score compared to the control group, but the combination of BMAC and PRP did not further enhance the histological score. Conclusions The clinical application of BMAC or PRP in osteochondral defect healing is attractive because of their autologous origin and cost-effectiveness. Adding either PRP or BMAC to a biphasic scaffold led to a significantly better healing of osteochondral defects compared with the control group. However, the combination of both therapies did not further enhance healing. PMID:23951201

  5. Salvage of a post-traumatic arthritic wrist using the scaphoid as an osteochondral graft.

    PubMed

    Marcuzzi, A; Ozben, H; Russomando, A

    2014-09-01

    The authors describe a case of post-traumatic wrist arthritis with an osteochondral defect in the scaphoid fossa of the radius. The patient was treated with proximal row carpectomy, radial styloidectomy and reconstruction of the defect using the proximal half of the scaphoid as an autologous osteochondral graft. Pain relief was achieved while wrist motion and strength were improved. The carpal bones are a source of osteochondral grafts and can be used to expand the indications of motion-preserving wrist salvage procedures.

  6. Analysis and Optimization of Spiral Circular Inductive Coupling Link for Bio-Implanted Applications on Air and within Human Tissue

    PubMed Central

    Mutashar, Saad; Hannan, Mahammad A.; Samad, Salina A.; Hussain, Aini

    2014-01-01

    The use of wireless communication using inductive links to transfer data and power to implantable microsystems to stimulate and monitor nerves and muscles is increasing. This paper deals with the development of the theoretical analysis and optimization of an inductive link based on coupling and on spiral circular coil geometry. The coil dimensions offer 22 mm of mutual distance in air. However, at 6 mm of distance, the coils offer a power transmission efficiency of 80% in the optimum case and 73% in the worst case via low input impedance, whereas, transmission efficiency is 45% and 32%, respectively, via high input impedance. The simulations were performed in air and with two types of simulated human biological tissues such as dry and wet-skin using a depth of 6 mm. The performance results expound that the combined magnitude of the electric field components surrounding the external coil is approximately 98% of that in air, and for an internal coil, it is approximately 50%, respectively. It can be seen that the gain surrounding coils is almost constant and confirms the omnidirectional pattern associated with such loop antennas which reduces the effect of non-alignment between the two coils. The results also show that the specific absorption rate (SAR) and power loss within the tissue are lower than that of the standard level. Thus, the tissue will not be damaged anymore. PMID:24984057

  7. Analysis and optimization of spiral circular inductive coupling link for bio-implanted applications on air and within human tissue.

    PubMed

    Mutashar, Saad; Hannan, Mahammad A; Samad, Salina A; Hussain, Aini

    2014-06-30

    The use of wireless communication using inductive links to transfer data and power to implantable microsystems to stimulate and monitor nerves and muscles is increasing. This paper deals with the development of the theoretical analysis and optimization of an inductive link based on coupling and on spiral circular coil geometry. The coil dimensions offer 22 mm of mutual distance in air. However, at 6 mm of distance, the coils offer a power transmission efficiency of 80% in the optimum case and 73% in the worst case via low input impedance, whereas, transmission efficiency is 45% and 32%, respectively, via high input impedance. The simulations were performed in air and with two types of simulated human biological tissues such as dry and wet-skin using a depth of 6 mm. The performance results expound that the combined magnitude of the electric field components surrounding the external coil is approximately 98% of that in air, and for an internal coil, it is approximately 50%, respectively. It can be seen that the gain surrounding coils is almost constant and confirms the omnidirectional pattern associated with such loop antennas which reduces the effect of non-alignment between the two coils. The results also show that the specific absorption rate (SAR) and power loss within the tissue are lower than that of the standard level. Thus, the tissue will not be damaged anymore.

  8. Controlled surface modification of Ti-40Nb implant alloy by electrochemically assisted inductively coupled RF plasma oxidation.

    PubMed

    Göttlicher, Markus; Rohnke, Marcus; Helth, Arne; Leichtweiß, Thomas; Gemming, Thomas; Gebert, Annett; Eckert, Jürgen; Janek, Jürgen

    2013-11-01

    Low temperature metal oxidation induced by plasma in the absence of liquid electrolytes can be useful for the surface preparation of orthopedic devices since residues from these may be harmful and need to be removed before implantation. In this study the oxidation of Ti-40Nb for biomedical application was achieved by employing an inductively coupled radio frequency oxygen plasma. The correlation between the growth mode of the surface oxide and the electric conductivity ratio of the plasma and the oxide phase were studied by varying the sample temperature, oxygen gas pressure and additional bias potential. The plasma treated samples were characterised by confocal laser microscopy, SEM, EBSD, XPS, TEM and ToF-SIMS. The surface energy was determined by contact angle measurements using the Owens-Wendt-Rabel-Kaelble method. Well adhering oxide layers consisting of TiO2 and Nb2O5 with thicknesses between 50 and 150 nm were obtained. Surface roughness values and microstructure indicate that the growth mode of the oxide can be well controlled by the sample temperature and oxygen gas pressure. At temperatures above 450°C a migration of Ti ions towards the surface controls the growth process. A bias potential higher than +50 V causes rough and defective surfaces with high surface energies. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  9. Apparatus for simulating dynamic interactions between the spinal cord and soft-coupled intradural implants

    NASA Astrophysics Data System (ADS)

    Viljoen, S.; Oya, H.; Reddy, C. G.; Dalm, B. D.; Shurig, R.; Odden, K.; Gillies, G. T.; Howard, M. A.

    2013-11-01

    We have designed, built, and tested an apparatus used for investigating the biomechanical response of a novel intradural spinal cord stimulator to the simulated physiological movement of the spinal cord within the thecal sac. In this apparatus, the rostral-caudal displacements of an anthropomorphic spinal cord surrogate can be controlled with a resolution of approximately 0.1% of a target value for up to 107 lateral movement cycles occurring at a repetition rate of 2 Hz. Using this system, we have been able to determine that the restoring force of the stimulator's suspension system works in concert with the frictional coupling between the electrode array and the surrogate to overcome the 0.42 μN inertial force associated with the lateral motion of the array. The result is a positional stability of the array on the surrogate (in air) of better than 0.2 mm over ˜500 000 movement cycles. Design modifications that might lead to improved physiological performance are discussed.

  10. Integrated Bi-Layered Scaffold for Osteochondral Tissue Engineering

    PubMed Central

    Galperin, Anna; Oldinski, Rachael A.; Florczyk, Stephen J.; Bryers, James D.; Zhang, Miqin

    2013-01-01

    Osteochondral tissue engineering poses the challenge of combining both cartilage and bone tissue engineering fundamentals. In this study, a sphere-templating technique was applied to fabricate an integrated bi-layered scaffold based on degradable poly(hydroxyethyl methacrylate) hydrogel. One layer of the integrated scaffold was designed with a single defined, monodispersed pore size of 38 μm and pore surfaces coated with hydroxyapatite particles to promote regrowth of subchondral bone while the second layer had 200 μm pores with surfaces decorated with hyaluronan for articular cartilage regeneration. Mechanical properties of the construct as well as cyto-compatibility of the scaffold and its degradation products were elucidated. To examine the potential of the biphasic scaffold for regeneration of osteochondral tissue the designated cartilage and bone layers of the integrated bi-layered scaffold were seeded with chondrocytes differentiated from human mesenchymal stem cells and primary human mesenchymal stem cells, respectively. Both types of cells were co-cultured within the scaffold in standard medium without soluble growth/differentiation factors over four weeks. The ability of the integrated bi-layered scaffold to support simultaneous matrix deposition and adequate cell growth of two distinct cell lineages in each layer during four weeks of co-culture in vitro in the absence of soluble growth factors was demonstrated. PMID:23225568

  11. Osteochondral tissue engineering: scaffolds, stem cells and applications

    PubMed Central

    Nooeaid, Patcharakamon; Salih, Vehid; Beier, Justus P; Boccaccini, Aldo R

    2012-01-01

    Osteochondral tissue engineering has shown an increasing development to provide suitable strategies for the regeneration of damaged cartilage and underlying subchondral bone tissue. For reasons of the limitation in the capacity of articular cartilage to self-repair, it is essential to develop approaches based on suitable scaffolds made of appropriate engineered biomaterials. The combination of biodegradable polymers and bioactive ceramics in a variety of composite structures is promising in this area, whereby the fabrication methods, associated cells and signalling factors determine the success of the strategies. The objective of this review is to present and discuss approaches being proposed in osteochondral tissue engineering, which are focused on the application of various materials forming bilayered composite scaffolds, including polymers and ceramics, discussing the variety of scaffold designs and fabrication methods being developed. Additionally, cell sources and biological protein incorporation methods are discussed, addressing their interaction with scaffolds and highlighting the potential for creating a new generation of bilayered composite scaffolds that can mimic the native interfacial tissue properties, and are able to adapt to the biological environment. PMID:22452848

  12. A functional agarose-hydroxyapatite scaffold for osteochondral interface regeneration

    PubMed Central

    Khanarian, Nora T.; Haney, Nora M.; Burga, Rachel A.; Lu, Helen H.

    2013-01-01

    Regeneration of the osteochondral interface is critical for integrative and functional cartilage repair. This study focuses on the design and optimization of a hydrogel-ceramic composite scaffold of agarose and hydroxyapatite (HA) for calcified cartilage formation. The first study objective was to compare the effects of HA on non-hypertrophic and hypertrophic chondrocytes cultured in the composite scaffold. Specifically, cell growth, biosynthesis, hypertrophy, and scaffold mechanical properties were evaluated. Next, the ceramic phase of the scaffold was optimized in terms of particle size (200 nm vs. 25 µm) and dose (0–6 w/v%). It was observed that while deep zone chondrocyte (DZC) biosynthesis and hypertrophy remained unaffected, hypertrophic chondrocytes measured higher matrix deposition and mineralization potential with the addition of HA. Most importantly, higher matrix content translated into significant increases in both compressive and shear mechanical properties. While cell hypertrophy was independent of ceramic size, matrix deposition was higher only with the addition of micron-sized ceramic particles. In addition, the highest matrix content, mechanical properties and mineralization potential were found in scaffolds with 3% micro-HA, which approximates both the mineral aggregate size and content of the native interface. These results demonstrate that the biomimetic hydrogel-ceramic composite is optimal for calcified cartilage formation and is a promising design strategy for osteochondral interface regeneration. PMID:22531222

  13. ARTHROSCOPIC TREATMENT OF OSTEOCHONDRAL LESIONS OF THE TALUS

    PubMed Central

    de Araujo, Mariana Korbage; de Cillo, Mario Sergio Paulillo; Bittar, Cinthia Kelly; Zabeu, José Luis Amin; Cezar, Caroliny Nociti Moreira

    2016-01-01

    ABSTRACT Objective: To assess pain and function of the ankle in patients with injuries up to 1.5 cm diameter by the American Orthopaedic Foot and Ankle Society (AOFAS) score after arthroscopic treatment. Methods: The AOFAS scale was applied before and after arthroscopy, as well as the degree of subjective satisfaction of ambulatory patients. Patients with type I osteochondral injuries, acute trauma, using plaster, presenting lesions in other joints of the lower limbs and cognitive impairment that would prevent the application of the satisfaction questionnaire were excluded from the study. Statistical analysis was performed using unpaired t test with Welch correction, Mann Whitney test, and ANOVA, with Kruskal Wallis test and Dun test, considering p value lower than 0.05. Results: There was an increased AOFAS scores after arthroscopic treatment in 52 (94.5%) patients. The mean values of AOFAS score in 55 patients was 77.32 ± 6.67 points preoperative and 93.10± 8.24 points postoperative, with a mean variation of 15.8 points, p<0.001. Patients with stage II, III and IV injuries showed an increased AOFAS scores after arthroscopic treatment, p<0.001. No difference was found between medial and lateral injuries, p >0.05. Conclusion: Patients with stage II, III or IV osteochondral injuries of the talus of up to 1.5 cm diameter, whether medial or lateral, showed a significant improvement after arthroscopic treatment. Level of Evidence III, Retrospective Study. PMID:26997911

  14. OSTEOCHONDRAL AUTOLOGOUS TRANSPLANTATION FOR TREATING CHONDRAL LESIONS IN THE PATELLA

    PubMed Central

    Cohen, Moises; Amaro, Joicemar Tarouco; Fernandes, Ricardo de Souza Campos; Arliani, Gustavo Gonçalves; Astur, Diego da Costa; Kaleka, Camila Cohen; Skaf, Abdalla

    2015-01-01

    Objective: The primary aim of this study was to assess the clinical and functional evolution of patients with total-thickness symptomatic cartilaginous injury of the patellar joint surface, treated by means of osteochondral autologous transplantation. Methods: This prospective study was conducted from June 2008 to March 2011 and involved 17 patients. The specific questionnaires of Lysholm, Kujala and Fulkerson were completed preoperatively and one year postoperatively in order to assess the affected knee, and SF-36 was used to assess these patients’ general quality of life. The nonparametric paired Wilcoxon test was used for statistical analysis on the pre and postoperative questionnaires. The data were analyzed using the SPSS for Windows software, version 16.0, and a significance level of 5% was used. Results: The Lysholm preoperative and postoperative average scores were 54.59 and 75.76 points (p < 0.05). The Fulkerson pre and postoperative average scores were 52.53 and 78.41 points (p < 0.05). Conclusions: We believe that autologous osteochondral transplantation is a good treatment method for total-thickness symptomatic chondral lesions of the joint surface of the patella. PMID:27042645

  15. Donor-site giant cell reaction following backfill with synthetic bone material during osteochondral plug transfer.

    PubMed

    Fowler, Donald E; Hart, Joseph M; Hart, Jennifer A; Miller, Mark D

    2009-10-01

    Osteochondral defects are common in younger, active patients. Multiple strategies have been used to treat these lesions, including microfracture and osteochondral plug transfer. We describe a patient experiencing chronic knee pain and a full-thickness cartilage defect on the lateral femoral condyle. After failing conservative management and microfracture surgery, the patient underwent osteochondral autograft plug transfer, with backfilling of the donor sites using synthetic bone graft substitute. Initial recovery was uncomplicated until the patient experienced pain following a twist of the knee. Magnetic resonance imaging for the subsequent knee injury revealed poor healing at the donor sites. The donor sites were debrided, and specimens revealed a foreign body giant cell reaction. Donor-site morbidity is of primary concern during osteochondral plug transfer; however, insufficient data exist to support the use of synthetic bone graft material. Our results indicate that off-label use of synthetic bone graft substitute during a primary procedure requires further investigation.

  16. Bilateral osteochondritis dissecans of the elbow treated by Herbert screw fixation.

    PubMed

    Inoue, G

    1991-09-01

    The case of a 15-year-old boy, a high-performance motocross rider, who developed bilateral osteochondritis dissecans of the elbow is described. Both lesions were successfully treated by Herbert screw internal fixation.

  17. Osteochondritis dissecans of the medial femoral condyle : New cell-free scaffold as a treatment option.

    PubMed

    Stadler, N; Trieb, K

    2016-08-01

    There is no gold standard in treating osteochondral lesions, which is why the treatment remains very challenging. Osteochondral defects can occur in any joint, but the most common locations are the knee and the ankle. Trauma, repeated microtrauma, avascular necrosis and osteochondritis dissecans (a special type of avascular necrosis) are blamed for the cartilage damage and the damage of adjacent subchondral bone. The self-healing ability of the cartilage is unfortunately very poor; thus, it is necessary to develop new methods of cartilage repair. Unfortunately, few data and long-term survival rates for these new scaffolds are available. We report a case of osteochondritis dissecans treated with a new cell-free scaffold MaioRegen® (Fin-Ceramica Faenza Spa, Faenza, Italy).

  18. Diagnosis and treatment of osteochondral lesions of the ankle: current concepts.

    PubMed

    Prado, Marcelo Pires; Kennedy, John G; Raduan, Fernando; Nery, Caio

    2016-01-01

    We conducted a wide-ranging review of the literature regarding osteochondral lesions of the ankle, with the aim of presenting the current concepts, treatment options, trends and future perspectives relating to this topic.

  19. The use of embryonic cells in the treatment of osteochondral defects of the knee: an ovine in vivo study

    PubMed Central

    MANUNTA, ANDREA FABIO; ZEDDE, PIETRO; PILICCHI, SUSANNA; ROCCA, STEFANO; POOL, ROY R.; DATTENA, MARIA; MASALA, GEROLAMO; MARA, LAURA; CASU, SARA; SANNA, DANIELA; MANUNTA, MARIA LUCIA; PASSINO, ERALDO SANNA

    2016-01-01

    Purpose the aim of this study was to determine whether local delivery of embryonic stem-like (ESL) cells into osteochondral defects in the femoral condyles of sheep would enhance regeneration of hyaline articular cartilage. Methods male ESL cells embedded in fibrin glue were engrafted into osteochondral defects in the medial condyles (ESL-M) of the left femur in 22 ewes. An identical defect was created in the medial condyle of the contralateral stifle joint and left untreated as a control (empty defect, ED). The ewes were divided into 5 groups. Four sheep each were euthanized at 1, 2, 6, and 12 months from surgery, and 6 ewes were euthanized 24 months post-implantation. To study the effect of varying loads on the long-term regeneration process, an identical defect was also created and ESL cell engraftment performed in the lateral condyle (ESL-L) of the left stifle joint of the animals in the 12- and 24-month groups. The evaluation of regenerated tissue was performed by biomechanical, macroscopic, histological, immunohistochemical (collagen type II) and fluorescent in situ hybridization (FISH) assays. Results no significant differences were found between treated and control sites in the biomechanical assays at any time point. ESL cell grafts showed significantly greater macroscopic evidence of regeneration as compared to controls at 24 months after surgery; significantly better histological evidence of repair in ESL-M samples versus controls was found throughout the considered period. At 24 months from surgery there was significantly improved integration of graft edges with the host tissue in the ESL-M as compared to the ESL-L samples, demonstrating that load bearing positively affects the long-term regeneration process. Conclusions ESL cells enhanced the regeneration of hyaline cartilage. FISH confirmed that the regenerative tissue originated from ESL cells. Clinical Relevance ESL cells are able to self-renew for prolonged periods without differentiation and, most

  20. Can a biomimetic osteochondral scaffold be a reliable alternative to prosthetic surgery in treating late-stage SPONK?

    PubMed

    Berruto, M; Ferrua, P; Uboldi, F; Pasqualotto, S; Ferrara, F; Carimati, G; Usellini, E; Delcogliano, M

    2016-12-01

    This study aimed to assess the reliability of the Maioregen® biomimetic osteochondral scaffold (Finceramica Faenza SpA, Faenza, Italy) as a salvage and joint-preserving procedure in the treatment of late-stage osteonecrosis of the knee. Eleven active patients aged under 65years and presenting with clinical and radiological signs of SPONK were treated with Maioregen®. All were clinically evaluated pre-operatively and yearly thereafter for a minimum of two years. Subjective IKDC and Lysholm Knee Scale scores were used to assess clinical outcome. A VAS scale served to quantify pre-operative pain and post-operative pain. Activity levels were evaluated pre-operatively and at follow-up using the Tegner Activity Scale. Subjective IKDC (40±15.0 to 65.7±14.8 (mean±SD)) and Lysholm Knee Scale (49.7±17.9 to 86.6±12.7 (mean±SD)) scores improved significantly from pre-operative evaluation (p<.01). VAS scores decreased from a pre-operative mean (±SD) of 6.3±2.5 to 1.6±2.7 at two years. The Tegner Activity Scale showed no significant differences between pre-injury and two-year follow-up. Two out of the 11 patients were symptomatic at 18months post implant and progressed to condylar collapse. These patients required total knee arthroplasty. Use of a biomimetic scaffold can be a valid option in the surgical treatment of SPONK in relatively young active patients. Indeed, this surgical technique, originally developed for osteochondritis dissecans, has been found to give good clinical results at medium-term follow-up of late-stage osteonecrosis treatment and could postpone or even avoid the need for joint replacement procedures. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Fixation of an osteochondral fragment after acute patellar dislocation in an immature skeleton☆☆☆

    PubMed Central

    Albuquerque, Rodrigo Pires e; Félix dos Santos Neto, José; Albuquerque, Maria Isabel Pires e; Giordano, Vincenzo; Pecegueiro do Amaral, Ney

    2014-01-01

    Fixation of an osteochondral fracture after acute patellar dislocation is an infrequent form of treatment. Likewise, the location of this fragment in the lateral region of the lateral femoral condyle, functioning as a free body, is uncommon. The aim of this study was to present a case of osteochondral fracture of the patella at an unusual site, along with the therapy used and the clinical follow-up. PMID:26229800

  2. Involvement of trauma in the pathogenesis of osteochondritis dissecans in swine.

    PubMed Central

    Nakano, T; Aherne, F X

    1988-01-01

    Limb joint soundness was examined in 40 pigs loaded into a wooden box cart and 40 control pigs not subjected to loading. On postmortem examination, eight loaded pigs showed osteochondritis dissecans in their medial humeral condyles, suggesting that porcine joints are vulnerable to osteochondral lesions when mechanically overloaded. Prevention of trauma by careful handling of pigs during penning and transportation should help to control joint lesions and lameness. PMID:3349396

  3. Biomarkers Affected by Impact Severity during Osteochondral Injury.

    PubMed

    Waters, Nicole Poythress; Stoker, Aaron M; Pfeiffer, Ferris M; Cook, James L

    2015-06-01

    Osteochondral injury elevates the risk for developing posttraumatic osteoarthritis (PTOA). Therefore, our objective was to evaluate the relationship between impact severity during injury to cell viability and biomarkers possibly involved in PTOA. Osteochondral explants (6 mm, n = 72) were harvested from cadaveric femoral condyles (N = 6). Using a test machine, each explant (except for No Impact) was subjected to mechanical impact at a velocity of 100 mm/s to 0.25, 0.5, 0.75, 1.0, or 1.25 mm maximum compression corresponding to Low, Low-Moderate, Moderate, Moderate-High, or High impact groups. Cartilage cell viability, collagen content, and proteoglycan content were assessed at either day 0 or after 12 days of culture. Culture media were assessed for prostaglandin E2 (PGE2); nitric oxide; granulocyte macrophage colony-stimulating factor (GM-CSF); interferon gamma (IFNγ); interleukin (IL)-2, -4, -6, -7, -8, -10, -15, -18; interferon gamma-induced protein 10 (IP-10); keratinocyte-derived chemoattractant (KC); monocyte chemoattractant protein-1 (MCP-1); tumor necrosis factor alpha (TNFα); and matrix metalloproteinase-2, -3, -8, -9, -13. There was increased impact energy absorbed for the High group compared with the Moderate-High group, Moderate group, and Low-Moderate group (p = 0.011, 0.048, 0.008, respectively). At day 0, there was decreased area cell viability for the High group compared with the Low-Moderate group (p = 0.035). At day 1, PGE2 was increased for the High group compared with the Moderate, Low-Moderate, Low, and No Impact groups (p ≤ 0.01). Cumulative PGE2 was increased for the Moderate-High and High groups compared with the Moderate, Low-Moderate, Low, and No Impact groups (p ≤ 0.036). At day 1, MCP-1 was increased for the Moderate-High and High groups compared with the Low and No Impact groups (p ≤ 0.032). Impact to osteochondral explants resulted in multiple levels of severity. PGE2 was sensitive to impact

  4. The effects of prolonged deep freezing on the biomechanical properties of osteochondral allografts.

    PubMed

    Rozen, Benjamin; Brosh, Tamar; Salai, Moshe; Herman, Amir; Dudkiewicz, Israel

    2009-02-01

    Musculo-skeletal allografts sterilized and deep frozen are among the most common human tissue to be preserved and utilized in modern medicine. The effects of a long deep freezing period on cortical bone has already been evaluated and found to be insignificant. However, there are no reports about the influences of a protracted deep freezing period on osteochondral allografts. One hundred osteochondral cylinders were taken from a fresh specimen and humeral heads of 1 year, 2 years, 3 years and 4 year old bones. Twenty chips from each period, with a minimum of 3 chips per humeral head. Each was mechanically tested by 3 point compression. The fresh osteochondral allografts were significantly mechanically better than the deep frozen osteochondral allografts. There was no statistical significant time dependent difference between the deep frozen groups in relation to the freezing period. Therefore, we conclude that, from the mechanical point of view deep freezing of osteochondral allografts over a period of 4 years, is safe without further deterioration of the biomechanical properties of the osteochondral allografts.

  5. Coupling of an active middle-ear implant to the long process of the incus using an elastic clip attachment.

    PubMed

    Schraven, Sebastian P; Mlynski, Robert; Dalhoff, Ernst; Heyd, Andreas; Wildenstein, Daniela; Rak, Kristen; Radeloff, Andreas; Hagen, Rudolf; Gummer, Anthony W

    2016-10-01

    The active middle-ear implant Vibrant Soundbridge(©) (VSB) is used to treat mild-to-severe sensorineural hearing losses. The standard surgical approach for incus vibroplasty is a mastoidectomy and a posterior tympanotomy, crimping the Floating Mass Transducer (FMT) to the long process of the incus (LPI) (standard crimped application). However, tight crimping increases the risk of necrosis of the LPI, resulting in reduction of energy transfer and loss of amplification. The aim of this study was to develop a new coupling device for the LPI, that does not require crimping, and to test its vibrational transfer properties in temporal-bone preparations. An extended antrotomy and a posterior tympanotomy were performed in ten fresh human temporal bones. As a control for normal middle-ear function, the tympanic membrane was stimulated acoustically and the vibration of the stapes footplate was measured by laser Doppler vibrometry (LDV). FMT-induced vibration responses of the stapes were then measured for the standard crimped application at the LPI and for the newly designed elastic long process coupler (LP coupler). For the LP coupler, velocity-amplitude responses in temporal-bone preparations showed increased mean amplitudes at around 1 kHz (∼10 dB) and a reduction between 1.8 and 6 kHz (13 dB on average for 2 ≤ f ≤ 5 kHz). In conclusion, attachment of the FMT to the LPI with the LP coupler leads to generally good mechanical and functional coupling in temporal-bone preparations with a notable disadvantage between 1.8 and 6 kHz. Due to its elastic clip attachment it is expected that the LP coupler will reduce the risk of necrosis of the incus long process, which has to been shown in further studies. Clinical results of the LP coupler are pending. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. [The future of treatment for chondral and osteochondral lesions].

    PubMed

    Cirpar, Meriç; Korkusuz, Feza

    2007-01-01

    The population of patients with symptomatic focal or generalized cartilage lesions is growing due to prolongation of life expectancy and to increasing frequency of sports injuries. Cartilage tissue lesions which were defined as untreatable in the past have now become treatable thanks to advances in basic scientific research. With the development of technologies regarding biomaterial, cell and local regulators, and with the introduction of new surgical techniques, it is estimated that, in the near future, clinical applications of cartilage tissue engineering will also receive particular attention in our country. Currently, all alternatives used in the treatment of cartilage lesions have merits and demerits, including arthroscopic debridement and lavage, mesenchymal stem cell stimulation, osteochondral replacement techniques, and autologous chondrocyte transplantation. Preliminary results of experimental cartilage tissue engineering are encouraging for the replacement of disrupted tissue with that having mechanical properties of hyaline cartilage. Clinical applications of cartilage tissue engineering include bioabsorbable scaffolds as extracellular collagen, hyaluronic acid matrices, and genetically engineered bioactive materials.

  7. Stifle osteochondritis dissecans in snow leopards (Uncia uncia).

    PubMed

    Herrin, Kimberly Vinette; Allan, Graeme; Black, Anthony; Aliah, Rhonda; Howlett, Cameron Rolfe

    2012-06-01

    Three snow leopard (Uncia uncia) cubs, female and male siblings and an unrelated female, had lameness attributed to osteochondritis dissecans (OCD) lesions noted at 6, 8, and 10 mo of age, respectively. All cubs were diagnosed with OCD via radiographs. The sibling cubs both had lesions of the right lateral femoral condyles, while the unrelated cub had bilateral lesions of the lateral femoral condyles. Subsequently, OCD was confirmed in all three cases during surgical correction of the lateral femoral condyle lesions via lateral stifle arthrotomies, flap removal, and debridement of the defect sites. Histopathology also supported the diagnosis of OCD. Postoperatively, the sibling cubs developed seromas at the incision sites and mild lameness, which resolved within a month. To date, two cubs have been orthopedically sound, while one of the sibling cubs has developed mild osteoarthritis. OCD has rarely been reported in domestic felids, and to the authors' knowledge these are the first reported cases of OCD in nondomestic felids.

  8. The natural history of osteochondral lesions in the ankle.

    PubMed

    van Dijk, C Niek; Reilingh, Mikel L; Zengerink, Maartje; van Bergen, Christiaan J A

    2010-01-01

    Most osteochondral lesions (defects) of the talar dome are caused by trauma, which may be a single event or repeated, less intense events (microtrauma). A lesion may heal, remain asymptomatic, or progress to deep ankle pain on weight bearing, prolonged joint swelling, and the formation of subchondral bone cysts. During loading, compression of the cartilage forces water into the microfractured subchondral bone. The increased flow and pressure of fluid in the subchondral bone can cause osteolysis and the slow development of a subchondral cyst. The pain does not arise from the cartilage lesion but most likely is caused by repetitive high fluid pressure during walking and a concomitant decrease in pH produced by osteoclasts, which sensitize the highly innervated subchondral bone. Prevention of further degeneration depends on several factors, including the repair of the subchondral bone plate and the correct alignment of the ankle joint.

  9. Computational biomechanics of articular cartilage of human knee joint: effect of osteochondral defects.

    PubMed

    Shirazi, R; Shirazi-Adl, A

    2009-11-13

    Articular cartilage and its supporting bone functional conditions are tightly coupled as injuries of either adversely affects joint mechanical environment. The objective of this study was set to quantitatively investigate the extent of alterations in the mechanical environment of cartilage and knee joint in presence of commonly observed osteochondral defects. An existing validated finite element model of a knee joint was used to construct a refined model of the tibial lateral compartment including proximal tibial bony structures. The response was computed under compression forces up to 2000 N while simulating localized bone damage, cartilage-bone horizontal split, bone overgrowth and absence of deep vertical collagen fibrils. Localized tibial bone damage increased overall joint compliance and substantially altered pattern and magnitude of contact pressures and cartilage strains in both tibia and femur. These alterations were further exacerbated when bone damage was combined with base cartilage split and absence of deep vertical collagen fibrils. Local bone boss markedly changed contact pressures and strain patterns in neighbouring cartilage. Bone bruise/fracture and overgrowth adversely perturbed the homeostatic balance in the mechanical environment of articulate cartilage surrounding and opposing the lesion as well as the joint compliance. As such, they potentially contribute to the initiation and development of post-traumatic osteoarthritis.

  10. Midterm results of osteochondral allograft transplantation to the humeral head.

    PubMed

    Riff, Andrew J; Yanke, Adam B; Shin, Jason J; Romeo, Anthony A; Cole, Brian J

    2017-07-01

    This study evaluated clinical outcomes of osteochondral allograft (OCA) transplantation for humeral head osteochondral defects. We hypothesized that patients with isolated humeral head disease would achieve favorable results and that patients with bipolar disease would experience inferior outcomes. We identified patients who underwent humeral head OCA transplantation. Subjective questionnaire data were obtained preoperatively and at a minimum of 2 years postoperatively. Radiographs were evaluated for graft incorporation. Failure was defined by conversion to shoulder arthroplasty, American Shoulder and Elbow Surgeons score <50, or dissatisfaction with the surgical result. Twenty patients (65% male) met inclusion criteria. Patients were an average age of 24.8 ± 8.1 years. Eleven patients underwent concomitant glenoid surgery (microfracture or meniscal allograft resurfacing). Follow-up was available for 18 patients (90%) at mean of 67 months. All grafts incorporated except 2. Four patients underwent shoulder arthroplasty at mean of 25 months postoperatively (all after pain pump chondrolysis). Eleven of the 20 patients were satisfied (all dissatisfied patients underwent glenoid surgery). Significant improvements (P < .001) were seen for the visual analog scale (from 6.1 to 1.5), Simple Shoulder Test (from 32 to 73), American Shoulder and Elbow Surgeons score (from 39 to 76), and the physical component of the 12-Item Short Form Survey (from 38 to 48). Pain pump patients who did not progress to arthroplasty experienced inferior satisfaction (40% vs. 87.5%, P = .04) and a trend toward inferior outcomes compared with the rest of the cohort. OCA transplantation is a viable option for young patients with isolated humeral chondral injury. Patients with bipolar disease or a history of intra-articular pain pump have increased failure and decreased subjective outcomes. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier

  11. Dorsoproximal proximal phalanx osteochondral fragmentation in 117 Warmblood horses.

    PubMed

    Declercq, J; Martens, A; Maes, D; Boussauw, B; Forsyth, R; Boening, K J

    2009-01-01

    The objective of the present study was to determine clinical and arthroscopic characteristics associated with dorsoproximal proximal phalanx (P1) fragments in Warmblood horses, as well as to examine their histopathological appearance. One hundred sixty-eight fragments were removed from 150 fetlocks of 117 Warmblood horses. Details of signalment and results of clinical examination were collected prior to surgery. After arthroscopic fragment removal and joint evaluation for synovial and/or cartilage abnormalities, the fragments were measured and evaluated histopathologically. The vast majority of the fragments (95.2%) were found medially, without predilection for front or hind limbs. In 10% of the joints, more than one fragment was present. The mean size of the fragments was 6.8 +/- 2.6 mm. Only eight horses presented fetlock-related lameness. Horses of seven years of age and older (OR = 13.32; p = 0.033) and the presence of more than one fragment (OR = 11.12; p = 0.016) were significantly associated with lameness. Arthroscopic evaluation revealed one or more abnormalities in 50.7% of the joints. On histopathology, osteochondral fragments presented as a bony center covered with smooth hyaline cartilage on one side and some fibrous tissue on the other side. No clear histopathological signs were indicating precisely their origin. In Warmblood horses with dorsoproximal P1 fragments, the age (seven years and older) and the presence of more than one fragment in a fetlock significantly increased the risk of lameness. The osteochondral dorsoproximal P1 fragments could be defined as a developmental orthopaedic disease.

  12. Additive manufacturing for in situ repair of osteochondral defects.

    PubMed

    Cohen, Daniel L; Lipton, Jeffrey I; Bonassar, Lawrence J; Lipson, Hod

    2010-09-01

    Tissue engineering holds great promise for injury repair and replacement of defective body parts. While a number of techniques exist for creating living biological constructs in vitro, none have been demonstrated for in situ repair. Using novel geometric feedback-based approaches and through development of appropriate printing-material combinations, we demonstrate the in situ repair of both chondral and osteochondral defects that mimic naturally occurring pathologies. A calf femur was mounted in a custom jig and held within a robocasting-based additive manufacturing (AM) system. Two defects were induced: one a cartilage-only representation of a grade IV chondral lesion and the other a two-material bone and cartilage fracture of the femoral condyle. Alginate hydrogel was used for the repair of cartilage; a novel formulation of demineralized bone matrix was used for bone repair. Repair prints for both defects had mean surface errors less than 0.1 mm. For the chondral defect, 42.8+/-2.6% of the surface points had errors that were within a clinically acceptable error range; however, with 1 mm path planning shift, an estimated approximately 75% of surface points could likely fall within the benchmark envelope. For the osteochondral defect, 83.6+/-2.7% of surface points had errors that were within clinically acceptable limits. In addition to implications for minimally invasive AM-based clinical treatments, these proof-of-concept prints are some of the only in situ demonstrations to-date, wherein the substrate geometry was unknown a priori. The work presented herein demonstrates in situ AM, suggests potential biomedical applications and also explores in situ-specific issues, including geometric feedback, material selection and novel path planning techniques.

  13. Low Grade Juvenile Osteochondritis Dissecans of the Knee

    PubMed Central

    Etcheto, H. Rivarola; Blanchod, C. Collazo; Palanconi, M.; Zordan, J.; Salinas, E. Alvarez; Autorino, C.

    2017-01-01

    Juvenile osteochondritis dissecans (OCD) of the knee is a nosological entity acquired, idiopathic and potentially reversible. Dissects the subchondral bone tissue plane from the underlying bone, making a partial or complete osteochondral detachment, with a loose body. Consensus to treat none surgically poor symptomatic and stable lesions. If the lesion becomes instable or more symptomatic, surgical treatment will be best the option. Recently histological evidence holds is possible find sources of instability in deep layers sub chondral bone, even in patients with ¨stables lesions¨. This condition might be the reason of unfavorable evolution certain cases previously considered as ¨stable or incipient¨, treated with the classic non operative protocols. Objectives: The purpose of the present study consist in present a series of cases of young patients with symptomatic low grade juvenile OCD (grade I-II), treated surgically with subchondral debridement and fixation ¨in situ¨ describing the clinical and imaging findings. Methods: We evaluated 15 cases of symptomatic juvenile OCD of the knee, stables lesion (grade I/ II) according to Di Paola´s classification, who have not responded to conservative therapy for at least 6 months. Results: All patients were treated surgical consecutively with arthroscopically assisted ¨in situ¨ fixation with pins Smart Nail NR, ConMed-Linvatex and for the same group of surgeons. We evaluated the clinical and imagenologic outcomes with MRI for a minimum follow up of six month to one year. No looseness of fastening material or loose bodies in the submitted sample were recorded. The study by MRI imaging techniques using high definition chondral identification evidence allowed the consolidation of the fragment to the 6th month. Conclusion: All patients evolved asymptomatic and returned to the previous activity, with high level of satisfaction.

  14. Optical Clearing in Collagen- and Proteoglycan-Rich Osteochondral Tissues

    PubMed Central

    Neu, Corey P.; Novak, Tyler; Gilliland, Kateri Fites; Marshall, Peter; Calve, Sarah

    2014-01-01

    Objective Recent developments in optical clearing and microscopy technology have enabled the imaging of intact tissues at the millimeter scale to characterize cells via fluorescence labeling. While these techniques have facilitated the three-dimensional cellular characterization within brain and heart, study of dense connective tissues of the musculoskeletal system have been largely unexplored. Here, we quantify how optical clearing impacted the cell and tissue morphology of collagen-, proteoglycan-, and mineral-rich cartilage and bone from the articulating knee joint. Methods Water-based fructose solutions were used for optical clearing of bovine osteochondral tissues, followed by imaging with transmission and confocal microscopy. To confirm preservation of tissue structure during the clearing process, samples were mechanically tested in unconfined compression and visualized by cryoSEM. Results Optical clearing enhanced light transmission through cartilage, but not subchondral bone regions. Fluorescent staining and immunolabeling was preserved through sample preparations, enabling imaging to cartilage depths 5 times deeper than previously reported, limited only by the working distance of the microscope objective. Chondrocyte volume remained unchanged in response to, and upon the reversal, of clearing. Equilibrium modulus increased in cleared samples, and was attributed to exchange of interstitial fluid with the more viscous fructose solution, but returned to control levels upon unclearing. In addition, cryoSEM-based analysis of cartilage showed no ultrastructural changes. Conclusion We anticipate large-scale microscopy of diverse connective tissues will enable the study of intact, three-dimensional interfaces (e.g. osteochondral) and cellular connectivity as a function of development, disease, and regeneration, which have been previously hindered by specimen opacity. PMID:25454370

  15. Evaluation of chitosan-GP hydrogel biocompatibility in osteochondral defects: an experimental approach

    PubMed Central

    2014-01-01

    Background Articular cartilage, because of its avascular nature, has little capacity for spontaneous healing, and tissue engineering approaches, employing different biomaterials and cells, are under development. Among the investigated biomaterials are the chitosan-based hydrogels. Although thoroughly studied in other mammalian species, studies are scarce in equines. So, the aim of the present study was to investigate the biocompatibility of chitosan-GP in horse joints submitted to high mechanical loads. Results An osteochondral defect was created by arthroscopy in the medial surface of lateral trochlea of talus of left or right leg, randomly selected, from six healthy geldings. The defect was filled up with chitosan-GP. The contralateral joint received an identical defect with no implant. The chondral fragment removed to produce the defect was collected, processed and used as the “Initial” sample (normal cartilage) for histology, immunohistochemistry, and metabolic labelling of PGs. After 180 days, the repair tissues were collected, and also analyzed. At the end of the experiment (180 days after lesion), the total number of cells per field in repair tissues was equal to control, and macrophages and polymorphonuclear cells were not detected, suggesting that no significant inflammation was present. These cells were able to synthesize type II collagen and proteoglycans (PGs). Nevertheless, the cell population in these tissues, both in presence of chitosan-GP and in untreated controls, were heterogeneous, with a lower proportion of type II collagen-positives cells and some with a fibroblastic aspect. Moreover, the PGs synthesized in repair tissues formed in presence or absence of chitosan-GP were similar to those of normal cartilage. However, the chitosan-GP treated tissue had an disorganized appearance, and blood vessels were present. Conclusions Implanted chitosan-GP did not evoke an important inflammatory reaction, and permitted cell growth. These cells were

  16. Simultaneous generation of intersubband absorption and quantum well intermixing through silicon ion implantation in undoped InGaAs/AlAsSb coupled double quantum wells

    NASA Astrophysics Data System (ADS)

    Cong, G. W.; Akimoto, R.; Gozu, S.; Mozume, T.; Hasama, T.; Ishikawa, H.

    2010-03-01

    We demonstrated the intersubband absorption in undoped InGaAs/AlAsSb coupled double quantum wells through silicon ion implantation and rapid thermal annealing. For an implantation dose of 1×1014 cm-2, the actual carrier density of a sample annealed at 600 °C for 1 min was ˜7.5×1013 cm-2 (˜75% activation efficiency); the activation energy was ˜1.41 eV. The simultaneously generated quantum well intermixing (QWI) was nonuniform due to the silicon ion distribution. The effects of QWI nonuniformity on both intersubband and interband transitions were explained by eight-band k ṡp calculation. This study will open a route for monolithic integration of intersubband-transition-based high-speed all-optical switches.

  17. Development of an inductively-coupled MR coil system for imaging and spectroscopic analysis of an implantable bioartificial construct at 11.1T

    PubMed Central

    Volland, Nelly A.; Mareci, Thomas H.; Constantinidis, Ioannis; Simpson, Nicholas E.

    2010-01-01

    Developing a method to non-invasively monitor tissue engineered constructs is critical for the optimization of construct design and for assessing therapeutic efficacy. For this purpose, NMR is a powerful technique that can be used to obtain both images and spectroscopic data. But the inherent sensitivity of NMR limits the observation of a bioartificial construct with current NMR surface coil technology. In this study, we address this limitation through the development of an inductively-coupled, implantable coil system, demonstrate its use at high field (11.1T), and investigate the use of this coil system for monitoring a bioartificial construct in vitro and in vivo. The results establish that large gains in signal-to-noise can be obtained with this coil system over that obtainable with a surface coil. This coil system provides a means to quantitatively analyze the structure and function of implanted bioartificial organs. PMID:20373400

  18. Integrating biologically inspired nanomaterials and table-top stereolithography for 3D printed biomimetic osteochondral scaffolds.

    PubMed

    Castro, Nathan J; O'Brien, Joseph; Zhang, Lijie Grace

    2015-09-07

    The osteochondral interface of an arthritic joint is notoriously difficult to regenerate due to its extremely poor regenerative capacity and complex stratified architecture. Native osteochondral tissue extracellular matrix is composed of numerous nanoscale organic and inorganic constituents. Although various tissue engineering strategies exist in addressing osteochondral defects, limitations persist with regards to tissue scaffolding which exhibit biomimetic cues at the nano to micro scale. In an effort to address this, the current work focused on 3D printing biomimetic nanocomposite scaffolds for improved osteochondral tissue regeneration. For this purpose, two biologically-inspired nanomaterials have been synthesized consisting of (1) osteoconductive nanocrystalline hydroxyapatite (nHA) (primary inorganic component of bone) and (2) core-shell poly(lactic-co-glycolic) acid (PLGA) nanospheres encapsulated with chondrogenic transforming growth-factor β1 (TGF-β1) for sustained delivery. Then, a novel table-top stereolithography 3D printer and the nano-ink (i.e., nHA + nanosphere + hydrogel) were employed to fabricate a porous and highly interconnected osteochondral scaffold with hierarchical nano-to-micro structure and spatiotemporal bioactive factor gradients. Our results showed that human bone marrow-derived mesenchymal stem cell adhesion, proliferation, and osteochondral differentiation were greatly improved in the biomimetic graded 3D printed osteochondral construct in vitro. The current work served to illustrate the efficacy of the nano-ink and current 3D printing technology for efficient fabrication of a novel nanocomposite hydrogel scaffold. In addition, tissue-specific growth factors illustrated a synergistic effect leading to increased cell adhesion and directed stem cell differentiation.

  19. Integrating biologically inspired nanomaterials and table-top stereolithography for 3D printed biomimetic osteochondral scaffolds

    NASA Astrophysics Data System (ADS)

    Castro, Nathan J.; O'Brien, Joseph; Zhang, Lijie Grace

    2015-08-01

    The osteochondral interface of an arthritic joint is notoriously difficult to regenerate due to its extremely poor regenerative capacity and complex stratified architecture. Native osteochondral tissue extracellular matrix is composed of numerous nanoscale organic and inorganic constituents. Although various tissue engineering strategies exist in addressing osteochondral defects, limitations persist with regards to tissue scaffolding which exhibit biomimetic cues at the nano to micro scale. In an effort to address this, the current work focused on 3D printing biomimetic nanocomposite scaffolds for improved osteochondral tissue regeneration. For this purpose, two biologically-inspired nanomaterials have been synthesized consisting of (1) osteoconductive nanocrystalline hydroxyapatite (nHA) (primary inorganic component of bone) and (2) core-shell poly(lactic-co-glycolic) acid (PLGA) nanospheres encapsulated with chondrogenic transforming growth-factor β1 (TGF-β1) for sustained delivery. Then, a novel table-top stereolithography 3D printer and the nano-ink (i.e., nHA + nanosphere + hydrogel) were employed to fabricate a porous and highly interconnected osteochondral scaffold with hierarchical nano-to-micro structure and spatiotemporal bioactive factor gradients. Our results showed that human bone marrow-derived mesenchymal stem cell adhesion, proliferation, and osteochondral differentiation were greatly improved in the biomimetic graded 3D printed osteochondral construct in vitro. The current work served to illustrate the efficacy of the nano-ink and current 3D printing technology for efficient fabrication of a novel nanocomposite hydrogel scaffold. In addition, tissue-specific growth factors illustrated a synergistic effect leading to increased cell adhesion and directed stem cell differentiation.

  20. Repair of articular cartilage defects with tissue-engineered osteochondral composites in pigs.

    PubMed

    Cui, Weiding; Wang, Qing; Chen, Gang; Zhou, Shixiang; Chang, Qing; Zuo, Qiang; Ren, Kewei; Fan, Weimin

    2011-04-01

    To compare the results of repair of knee cartilage defects with tissue-engineered osteochondral composites and tissue-engineered cartilage in pigs. Autologous chondrocytes and osteoblasts were seeded on scaffolds of polylactic-co-glycolic acid (PLGA) and tricalcium phosphate (TCP) to generate tissue-engineered cartilage and tissue-engineered bone, respectively. The tissue-engineered osteochondral composite was formed by a chondrocyte-PLGA construct sutured to an osteoblast-TCP construct with an absorbable suture. Cartilage defects were surgically created at the weightbearing surface of the bilateral femoral medial condyles of 12 mini-pigs. Thus, 24 defects in 12 pigs were randomly assigned to three treatment groups: tissue-engineered osteochondral composite group, tissue-engineered cartilage group, and blank control group. Six months after surgery, the regenerated cartilage was scored macroscopically and histologically. The compressive properties and glycosaminoglycan (GAG) content of the cartilage were also assessed. The gross grading scale indicated that the mean scores of the tissue-engineered osteochondral composite group were significantly higher than those of the tissue-engineered cartilage group. According to the International Cartilage Repair Society (ICRS) Visual Histological Assessment Scale, the scores of the osteochondral composite group were significantly better than those of the tissue-engineered cartilage group and blank control group. Assessment of compressive properties and GAG content showed better repair results in the osteochondral composite group than those of the tissue-engineered cartilage group. Using tissue-engineered osteochondral composites to repair cartilage defects was better than that of tissue-engineered cartilage.

  1. Microporous calcium phosphate ceramics as tissue engineering scaffolds for the repair of osteochondral defects: biomechanical results.

    PubMed

    Mayr, H O; Klehm, J; Schwan, S; Hube, R; Südkamp, N P; Niemeyer, P; Salzmann, G; von Eisenhardt-Rothe, R; Heilmann, A; Bohner, M; Bernstein, A

    2013-01-01

    This work investigated the suitability of microporous β-tricalcium phosphate (TCP) scaffolds pre-seeded with autologous chondrocytes for treatment of osteochondral defects in a large animal model. Microporous β-TCP cylinders (Ø 7 mm; length 25 mm) were seeded with autologous chondrocytes and cultured for 4 weeks in vitro. Only the upper end of the cylinder was seeded with chondrocytes. Chondrocytes formed a multilayer on the top. The implants were then implanted in defects (diameter 7 mm) created in the left medial femoral condyle of ovine knees. The implants were covered with synovial membrane from the superior recess of the same joint. For the right knees, an empty defect with the same dimensions served as control. Twenty-eight sheep were split into 6-, 12-, 26- and 52 week groups of seven animals. Indentation tests with a spherical (Ø 3mm) indenter were used to determine the biomechanical properties of regenerated tissue. A software-based limit switch was implemented to ensure a maximal penetration depth of 200 μm and maximal load of 1.5 N. The achieved load, the absorbed energy and the contact stiffness were measured. Newly formed cartilage was assessed with the International Cartilage Repair Society Visual Assessment Scale (ICRS score) and histomorphometric analysis. Results were analysed statistically using the t-test, Mann-Whitney U-test and Wilcoxon test. Statistical significance was set at p<0.05. After 6 weeks of implantation, the transplanted area tolerated an indentation load of 0.05±0.20 N. This value increased to 0.10±0.06 N after 12 weeks, to 0.27±0.18 N after 26 weeks, and 0.27±0.11 N after 52 weeks. The increase in the tolerated load was highly significant (p<0.0001), but the final value was not significantly different from that of intact cartilage (0.30±0.12 N). Similarly, the increase in contact stiffness from 0.87±0.29 N mm-(1) after 6 weeks to 3.14±0.86 N mm(-1) after 52 weeks was highly significant (p<0.0001). The absorbed energy

  2. Dynamic regulation of bone morphogenetic proteins in engineered osteochondral constructs by biomechanical stimulation.

    PubMed

    Nam, Jin; Perera, Priyangi; Rath, Bjoern; Agarwal, Sudha

    2013-03-01

    Osteochondral tissue-engineered grafts are proposed to hold greater potential to repair/regenerate damaged cartilage through enhanced biochemical and mechanical interactions with underlying subchondral bone as compared to simple engineered cartilage. Additionally, biomechanical stimulation of articular chondrocytes (ACs) or osteoblasts (OBs) was shown to induce greater morphogenesis of the engineered tissues composed of these cells. In this report, to define the advantages of biomechanical stimulation to osteochondral grafts for tissue engineering, we examined whether (1) ACs and OBs in three-dimensional (3D) osteochondral constructs support functional development of each other at the molecular level, and (2) biomechanical stimulation of osteochondral constructs further promotes the regenerative potential of such grafts. Various configurations of cell/scaffold assemblies, including chondral, osseous, and osteochondral constructs, were engineered with mechano-responsive electrospun poly(ɛ-caprolactone) scaffolds. These constructs were subjected to either static or dynamic (10% cyclic compressive strain at 1 Hz for 3 h/day) culture conditions for 2 weeks. The expression of bone morphogenetic proteins (BMPs) was examined to assess the regenerative potential of each treatment on the cells. Biomechanical stimulation augmented a marked upregulation of Bmp2, Bmp6, and Bmp7 as well as downregulation of BMP antagonist, Bmp3, in a time-specific manner in the ACs and OBs of 3D osteochondral constructs. More importantly, the presence of biomechanically stimulated OBs was especially crucial for the induction of Bmp6 in ACs, a BMP required for chondrocytic growth and differentiation. Biomechanical stimulation led to enhanced tissue morphogenesis possibly through this BMP regulation, evident by the improved effective compressive modulus of the osteochondral constructs (710 kPa of dynamic culture vs. 280 kPa of static culture). Similar BMP regulation was observed in the

  3. Design of a Novel 3D Printed Bioactive Nanocomposite Scaffold for Improved Osteochondral Regeneration.

    PubMed

    Castro, Nathan J; Patel, Romil; Zhang, Lijie Grace

    2015-09-01

    Chronic and acute osteochondral defects as a result of osteoarthritis and trauma present a common and serious clinical problem due to the tissue's inherent complexity and poor regenerative capacity. In addition, cells within the osteochondral tissue are in intimate contact with a 3D nanostructured extracellular matrix composed of numerous bioactive organic and inorganic components. As an emerging manufacturing technique, 3D printing offers great precision and control over the microarchitecture, shape and composition of tissue scaffolds. Therefore, the objective of this study is to develop a biomimetic 3D printed nanocomposite scaffold with integrated differentiation cues for improved osteochondral tissue regeneration. Through the combination of novel nano-inks composed of organic and inorganic bioactive factors and advanced 3D printing, we have successfully fabricated a series of novel constructs which closely mimic the native 3D extracellular environment with hierarchical nanoroughness, microstructure and spatiotemporal bioactive cues. Our results illustrate several key characteristics of the 3D printed nanocomposite scaffold to include improved mechanical properties as well as excellent cytocompatibility for enhanced human bone marrow-derived mesenchymal stem cell adhesion, proliferation, and osteochondral differentiation in vitro. The present work further illustrates the effectiveness of the scaffolds developed here as a promising and highly tunable platform for osteochondral tissue regeneration.

  4. Osteochondral autologous transplantation for the treatment of full-thickness articular cartilage defects of the shoulder.

    PubMed

    Scheibel, M; Bartl, C; Magosch, P; Lichtenberg, S; Habermeyer, P

    2004-09-01

    We performed eight osteochondral autologous transplantations from the knee joint to the shoulder. All patients (six men, two women; mean age 43.1 years) were documented prospectively. In each patient the stage of the osteochondral lesion was Outerbridge grade IV with a mean size of the affected area of 150 mm2. All patients were assessed by using the Constant score for the shoulder and the Lysholm score for the knee. Standard radiographs, magnetic resonance imaging and second-look arthroscopy were used to assess the presence of glenohumeral osteoarthritis and the integrity of the grafts. After a mean of 32.6 months (8 to 47), the mean Constant score increased significantly. Magnetic resonance imaging revealed good osseointegration of the osteochondral plugs and congruent articular cartilage at the transplantation site in all but one patient. Second-look arthroscopy performed in two cases revealed a macroscopically good integration of the autograft with an intact articular surface. Osteochondral autologous transplantation in the shoulder appears to offer good clinical results for treating full-thickness osteochondral lesions of the glenohumeral joint. However, our study suggests that the development of osteoarthritis and the progression of pre-existing osteoarthritic changes cannot be altered by this technique.

  5. A biomimetic multi-layered collagen-based scaffold for osteochondral repair.

    PubMed

    Levingstone, Tanya J; Matsiko, Amos; Dickson, Glenn R; O'Brien, Fergal J; Gleeson, John P

    2014-05-01

    Cartilage and osteochondral defects pose a significant challenge in orthopedics. Tissue engineering has shown promise as a potential method for the treatment of such defects; however, a long-lasting repair strategy has yet to be realized. This study focuses on the development of a layered construct for osteochondral repair, fabricated through a novel "iterative layering" freeze-drying technique. The process involved repeated steps of layer addition followed by freeze-drying, enabling control over material composition, pore size and substrate stiffness in each region of the construct, while also achieving a seamlessly integrated layer structure. The novel construct developed mimics the inherent gradient structure of healthy osteochondral tissue: a bone layer composed of type I collagen and hydroxyapatite (HA), an intermediate layer composed of type I collagen, type II collagen and HA and a cartilaginous region composed of type I collagen, type II collagen and hyaluronic acid. The material properties were designed to provide the biological cues required to encourage infiltration of host cells from the bone marrow while the biomechanical properties were designed to provide an environment optimized to promote differentiation of these cells towards the required lineage in each region. This novel osteochondral graft was shown to have a seamlessly integrated layer structure, high levels of porosity (>97%), a homogeneous pore structure and a high degree of pore interconnectivity. Moreover, homogeneous cellular distribution throughout the entire construct was evident following in vitro culture, demonstrating the potential of this multi-layered scaffold as an advanced strategy for osteochondral defect repair.

  6. Polymers, scaffolds and bioactive molecules with therapeutic properties in osteochondral pathologies: what's new?

    PubMed

    López-Ruiz, Elena; Jiménez, Gema; García, María Ángel; Antich, Cristina; Boulaiz, Houria; Marchal, Juan Antonio; Perán, Macarena

    2016-08-01

    Despite clinical efforts, treatments to heal osteochondral lesions remain inefficient and frequently result, long-term, in joint arthroplasty. The complex structure of cartilage tissue, composed of a highly hydrated extracellular matrix (ECM), an avascular nature, and slow cellular turnover, hamper tissue regeneration after trauma or disease. Tissue engineering provides new promising alternatives to current treatments designed to regenerate osteochondral defects. This review describes current and recent strategies of enhancing osteochondral repair through the use of cells, scaffolds, and bioactive molecules. Here, we review the latest (2011-2015) innovative patents in osteochondral regeneration, emphasizing novel strategies for articular cartilage repair. Finally, we present a summary of ongoing clinical trials that are testing innovative engineered products. Promising tissue engineering based procedures have emerged as a therapeutic option for the treatment of osteochondral lesions. The development of multilayer scaffolds and the controlled release of bioactive molecules to promote in situ regeneration of both cartilage and bone are some of the latest technologies that intended to improve on the available traditional treatments. To confirm the potential of these novel approaches, long-term evaluation is necessary with special focus on studying the biological and mechanical proprieties of the synthesized tissues.

  7. A biphasic scaffold based on silk and bioactive ceramic with stratified properties for osteochondral tissue regeneration.

    PubMed

    Li, Jiao Jiao; Kim, Kyungsook; Roohani-Esfahani, Seyed-Iman; Guo, Jin; Kaplan, David L; Zreiqat, Hala

    2015-07-14

    Significant clinical challenges encountered in the effective long-term treatment of osteochondral defects have inspired advancements in scaffold-based tissue engineering techniques to aid repair and regeneration. This study reports the development of a biphasic scaffold produced via a rational combination of silk fibroin and bioactive ceramic with stratified properties to satisfy the complex and diverse regenerative requirements of osteochondral tissue. Structural examination showed that the biphasic scaffold contained two phases with different pore morphologies to match the cartilage and bone segments of osteochondral tissue, which were joined at a continuous interface. Mechanical assessment showed that the two phases of the biphasic scaffold imitated the load-bearing behaviour of native osteochondral tissue and matched its compressive properties. In vitro testing showed that different compositions in the two phases of the biphasic scaffold could direct the preferential differentiation of human mesenchymal stem cells towards the chondrogenic or osteogenic lineage. By featuring simple and reproducible fabrication and a well-integrated interface, the biphasic scaffold strategy established in this study circumvented the common problems experienced with integrated scaffold designs and could provide an effective approach for the regeneration of osteochondral tissue.

  8. Design of a Novel 3D Printed Bioactive Nanocomposite Scaffold for Improved Osteochondral Regeneration

    PubMed Central

    Castro, Nathan J.; Patel, Romil; Zhang, Lijie Grace

    2015-01-01

    Chronic and acute osteochondral defects as a result of osteoarthritis and trauma present a common and serious clinical problem due to the tissue's inherent complexity and poor regenerative capacity. In addition, cells within the osteochondral tissue are in intimate contact with a 3D nanostructured extracellular matrix composed of numerous bioactive organic and inorganic components. As an emerging manufacturing technique, 3D printing offers great precision and control over the microarchitecture, shape and composition of tissue scaffolds. Therefore, the objective of this study is to develop a biomimetic 3D printed nanocomposite scaffold with integrated differentiation cues for improved osteochondral tissue regeneration. Through the combination of novel nano-inks composed of organic and inorganic bioactive factors and advanced 3D printing, we have successfully fabricated a series of novel constructs which closely mimic the native 3D extracellular environment with hierarchical nanoroughness, microstructure and spatiotemporal bioactive cues. Our results illustrate several key characteristics of the 3D printed nanocomposite scaffold to include improved mechanical properties as well as excellent cytocompatibility for enhanced human bone marrow-derived mesenchymal stem cell adhesion, proliferation, and osteochondral differentiation in vitro. The present work further illustrates the effectiveness of the scaffolds developed here as a promising and highly tunable platform for osteochondral tissue regeneration. PMID:26366231

  9. A preliminary study of osteochondral regeneration using a scaffold-free three-dimensional construct of porcine adipose tissue-derived mesenchymal stem cells.

    PubMed

    Murata, Daiki; Tokunaga, Satoshi; Tamura, Tadashi; Kawaguchi, Hiroaki; Miyoshi, Noriaki; Fujiki, Makoto; Nakayama, Koichi; Misumi, Kazuhiro

    2015-03-18

    Osteoarthritis (OA) is a major joint disease in humans and many other animals. Consequently, medical countermeasures for OA have been investigated diligently. This study was designed to examine the regeneration of articular cartilage and subchondral bone using three-dimensional (3D) constructs of adipose tissue-derived mesenchymal stem cells (AT-MSCs). AT-MSCs were isolated and expanded until required for genetical and immunological analysis and construct creation. A construct consisting of about 760 spheroids that each contained 5.0 × 10(4) autologous AT-MSCs was implanted into an osteochondral defect (diameter: 4 mm; depth: 6 mm) created in the femoral trochlear groove of two adult microminipigs. After implantation, the defects were monitored by computed tomography every month for 6 months in animal no. 1 and 12 months in animal no. 2. AT-MSCs were confirmed to express the premature genes and to be positive for CD90 and CD105 and negative for CD34 and CD45. Under specific nutrient conditions, the AT-MSCs differentiated into osteogenic, chondrogenic, and adipogenic lineages, as evidenced by the expressions of related marker genes and the production of appropriate matrix molecules. A radiopaque area emerged from the boundary between the bone and the implant and increased more steadily upward and inward for the implants in both animal no. 1 and animal no. 2. The histopathology of the implants after 6 months revealed active endochondral ossification underneath the plump fibrocartilage in animal no. 1. The histopathology after 12 months in animal no. 2 showed not only that the diminishing fibrocartilage was as thick as the surrounding normal cartilage but also that massive subchondral bone was present. The present results suggest that implantation of a scaffold-free 3D construct of AT-MSCs into an osteochondral defect may induce regeneration of the original structure of the cartilage and subchondral bone over the course of 1 year, although more

  10. Study on quantitative analysis of Ti, Al and V in clinical soft tissues after placing the dental implants by laser ablation inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Sajnóg, Adam; Hanć, Anetta; Makuch, Krzysztof; Koczorowski, Ryszard; Barałkiewicz, Danuta

    2016-11-01

    Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used for in-situ quantitative analysis of oral mucosa of patients before and after implantation with titanium implants and a closing screw based on Ti6Al4V alloy. Two calibration strategies were applied, both were based on matrix matched solid standards with analytes addition. A novel approach was the application of powdered egg white proteins as a matrix material which have a similar composition to the examined tissue. In the another approach, certified reference material Bovine Muscle ERM-BB184 was used. The isotope 34S was found to be the most appropriate as an internal standard since it is homogenously distributed in the examined tissues and resulted in lower relative standard deviation values of signal of analytes of interest. Other isotopes (13C, 26Mg, 43Ca) were also evaluated as potential internal standards. The analytical performance parameters and microwave digestion of solid standards followed by solution nebulization ICP-MS analysis proved that both calibration methods are fit for their intended purpose. The LA-ICP-MS analysis on the surface of tissues after the implantation process revealed an elevated content of elements in comparison to the control group. Analytes are distributed inhomogeneously and display local maximal content of Ti up to ca. 900 μg g- 1, Al up to ca. 760 μg g- 1 and for V up to 160 μg g- 1.

  11. Retrospective Cohort Study of 207 Cases of Osteochondritis Dissecans of the Knee

    PubMed Central

    Green, Daniel W.; Arbucci, John; Silberman, Jason; Luderowski, Eva; Uppstrom, Tyler J.; Nguyen, Joseph; Tuca, Maria

    2016-01-01

    Objectives: Describe the clinical characteristics, image findings, and outcomes of patients with juvenile osteochondritis dissecans (JOCD) of the knee. To our knowledge, this is the largest single-surgeon cohort of JOCD patients. Methods: Retrospective cohort study of knee JOCD patients assessed by a single pediatric orthopaedic surgeon at a tertiary care center between 2005-2015. All diagnoses were confirmed by magnetic resonance imaging (MRI). Patients with patellar dislocations or osteochondral fractures were excluded. Demographic data, sports played, comorbidities, surgical procedures, and clinical data were extracted from charts. Images were analyzed to identify the location and size of lesions. Chi-square or Fisher’s exact tests were used to compare discrete variables, and Mann-Whitney U and Kruskal Wallis tests to compare continuous variables between groups. P-values of <0.05 were considered significant. Results: Sample consisted of 180 patients (207 knees), 124 boys and 56 girls. Average age at diagnosis was 12.8 years (7.5-17.5). Majority were active in sports (80.8%), primary soccer (36.7%) and basketball (29.4%). JOCD was present bilaterally in 27 patients (15%), 14 knees had bifocal OCD (6.8%), and only 1 patient had bifocal lesions in both knees. Most common location was medial femoral condyle (56.3%) followed by lateral femoral condyle (23.1%), trochlea (11.4%), patella (9%), and tibia (0.5%). In the sagittal view, most common location was the middle third of the condyles (48.7%). Surgery was performed in 72 knees (34.8%), with an average age at surgery of 14.1 years (9.3-18.1). Bilateral JOCD was present in 13 surgical patients (18.8%), but only 3 patients had bilateral surgery. Two operative patients had bifocal JOCD (2.7%) and surgery on both lesions. Location distribution did not differ between surgical and non-surgical lesions. The average normalized area of non-surgical JOCD lesions was 6.8 (0.1-18), whereas surgical lesions averaged a

  12. COUPLING

    DOEpatents

    Frisch, E.; Johnson, C.G.

    1962-05-15

    A detachable coupling arrangement is described which provides for varying the length of the handle of a tool used in relatively narrow channels. The arrangement consists of mating the key and keyhole formations in the cooperating handle sections. (AEC)

  13. TREATMENT OF OSTEOCHONDRAL LESIONS OF THE TALUS BY MEANS OF THEARTHROSCOPY-ASSISTED MICROPERFORATION TECHNIQUE

    PubMed Central

    de Lima, Everton; de Queiroz, Felipe; Lopes, Osmar Valadão; Spinelli, Leandro de Freitas

    2015-01-01

    Objective: To evaluate patients affected by osteochondral fractures of the talus who were treated surgically by means of arthroscopy-assisted microperforation. Methods: A retrospective study was carried out on 24 patients with osteochondral lesions of the talus who underwent microperforation assisted by videoarthroscopy of the ankle. They were evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) score system before and after the operation. Results: There were 19 men and 5 women, with a mean age of 35.3 years (minimum of 17 years and maximum of 54 years). The minimum follow-up was two years (maximum of 39 months). All the patients showed an improvement in AOFAS score after surgery, with an average improvement of around 22.5 points. Conclusion: Videoarthroscopy-assisted microperforation is a good option for treating osteochondral lesions of the talus and provides good functional results. PMID:27027076

  14. Acute Osteochondral Fractures in the Lower Extremities - Approach to Identification and Treatment

    PubMed Central

    Pedersen, M.E; DaCambra, M.P; Jibri, Z; Dhillon, S; Jen, H; Jomha, N.M

    2015-01-01

    Chondral and osteochondral fractures of the lower extremities are important injuries because they can cause pain and dysfunction and often lead to osteoarthritis. These injuries can be misdiagnosed initially which may impact on the healing potential and result in poor long-term outcome. This comprehensive review focuses on current pitfalls in diagnosing acute osteochondral lesions, potential investigative techniques to minimize diagnostic errors as well as surgical treatment options. Acute osteochondral fractures are frequently missed and can be identified more accurately with specific imaging techniques. A number of different methods can be used to fix these fractures but attention to early diagnosis is required to limit progression to osteoarthritis. These fractures are common with joint injuries and early diagnosis and treatment should lead to improved long term outcomes. PMID:26587063

  15. Hierarchical Structure of Articular Bone-Cartilage Interface and Its Potential Application for Osteochondral Tissue Engineering

    NASA Astrophysics Data System (ADS)

    Bian, Weiguo; Qin, Lian; Li, Dichen; Wang, Jin; Jin, Zhongmin

    2010-09-01

    The artificial biodegradable osteochondral construct is one of mostly promising lifetime substitute in the joint replacement. And the complex hierarchical structure of natural joint is important in developing the osteochondral construct. However, the architecture features of the interface between cartilage and bone, in particular those at the micro-and nano-structural level, remain poorly understood. This paper investigates these structural data of the cartilage-bone interface by micro computerized tomography (μCT) and Scanning Electron Microscope (SEM). The result of μCT shows that important bone parameters and the density of articular cartilage are all related to the position in the hierarchical structure. The conjunctions of bone and cartilage were defined by SEM. All of the study results would be useful for the design of osteochondral construct further manufactured by nano-tech. A three-dimensional model with gradient porous structure is constructed in the environment of Pro/ENGINEERING software.

  16. Gingival Mesenchymal Stem Cell (GMSC) Delivery System Based on RGD-Coupled Alginate Hydrogel with Antimicrobial Properties: A Novel Treatment Modality for Peri-Implantitis.

    PubMed

    Diniz, Ivana M A; Chen, Chider; Ansari, Sahar; Zadeh, Homayoun H; Moshaverinia, Maryam; Chee, Daniel; Marques, Márcia M; Shi, Songtao; Moshaverinia, Alireza

    2016-02-01

    Peri-implantitis is one of the most common inflammatory complications in dental implantology. Similar to periodontitis, in peri-implantitis, destructive inflammatory changes take place in the tissues surrounding a dental implant. Bacterial flora at the failing implant sites resemble the pathogens in periodontal disease and consist of Gram-negative anaerobic bacteria including Aggregatibacter actinomycetemcomitans (Aa). Here we demonstrate the effectiveness of a silver lactate (SL)-containing RGD-coupled alginate hydrogel scaffold as a promising stem cell delivery vehicle with antimicrobial properties. Gingival mesenchymal stem cells (GMSCs) or human bone marrow mesenchymal stem cells (hBMMSCs) were encapsulated in SL-loaded alginate hydrogel microspheres. Stem cell viability, proliferation, and osteo-differentiation capacity were analyzed. Our results showed that SL exhibited antimicrobial properties against Aa in a dose-dependent manner, with 0.50 mg/ml showing the greatest antimicrobial properties while still maintaining cell viability. At this concentration, SL-containing alginate hydrogel was able to inhibit Aa growth on the surface of Ti discs and significantly reduce the bacterial load in Aa suspensions. Silver ions were effectively released from the SL-loaded alginate microspheres for up to 2 weeks. Osteogenic differentiation of GMSCs and hBMMSCs encapsulated in the SL-loaded alginate microspheres were confirmed by the intense mineral matrix deposition and high expression of osteogenesis-related genes. Taken together, our findings confirm that GMSCs encapsulated in RGD-modified alginate hydrogel containing SL show promise for bone tissue engineering with antimicrobial properties against Aa bacteria in vitro. © 2015 by the American College of Prosthodontists.

  17. Gingival Mesenchymal Stem Cell (GMSC) Delivery System Based on RGD-Coupled Alginate Hydrogel with Antimicrobial Properties: A Novel Treatment Modality for Peri-Implantitis

    PubMed Central

    Diniz, Ivana M. A.; Chen, Chider; Ansari, Sahar; Zadeh, Homayoun H.; Moshaverinia, Maryam; Chee, Daniel; Marques, Márcia M.; Shi, Songtao; Moshaverinia, Alireza

    2015-01-01

    Purpose Peri-implantitis is one of the most common inflammatory complications in dental implantology. Similar to periodontitis, in peri-implantitis, destructive inflammatory changes take place in the tissues surrounding a dental implant. Bacterial flora at the failing implant sites resemble the pathogens in periodontal disease and consist of Gram-negative anaerobic bacteria including Aggregatibacter actinomycetemcomitans (Aa). Here we demonstrate the effectiveness of a silver lactate (SL)-containing RGD-coupled alginate hydrogel scaffold as a promising stem cell delivery vehicle with antimicrobial properties. Materials and Methods Gingival mesenchymal stem cells (GMSCs) or human bone marrow mesenchymal stem cells (hBMMSCs) were encapsulated in SL-loaded alginate hydrogel microspheres. Stem cell viability, proliferation, and osteo-differentiation capacity were analyzed. Results Our results showed that SL exhibited antimicrobial properties against Aa in a dose-dependent manner, with 0.50 mg/ml showing the greatest antimicrobial properties while still maintaining cell viability. At this concentration, SL-containing alginate hydrogel was able to inhibit Aa on the surface of Ti discs and significantly reduce the bacterial load in Aa suspensions. Silver ions were effectively released from the SL-loaded alginate microspheres for up to 2 weeks. Osteogenic differentiation of GMSCs and hBMMSCs encapsulated in the SL-loaded alginate microspheres were confirmed by the intense mineral matrix deposition and high expression of osteogenesis-related genes. Conclusion Taken together, our findings confirm that GMSCs encapsulated in RGD-modified alginate hydrogel containing SL show promise for bone tissue engineering with antimicrobial properties against Aa bacteria in vitro. PMID:26216081

  18. Mechanical integrity of subchondral bone in osteochondral autografts and allografts

    PubMed Central

    Wohl, Greg; Goplen, Gordon; Ford, Jason; Novak, Kelli; Hurtig, Mark; McPherson, Roger; McGann, Locksley; Schachar, Norman; Zernicke, Ronald F.

    1998-01-01

    Objective To assess the influence of osteochondral graft preservation techniques on post-transplant biomechanics of graft and host subchondral bone in the knee joint. Design An experimental animal model (sheep), specifically the weight-bearing articular surface of the medial femoral condyle of the knee joints. Intervention Each sheep received, in the ipsilateral knee, an allograft that was (a) frozen without dimethyl sulfoxide (DMSO), (b) snap-frozen in liquid nitrogen or (c) frozen with DMSO. The contralateral knee received an autograft that was (a) snap-frozen, (b) treated with DMSO or (c) left untreated (fresh). Main outcome measures Mechanical and material properties of bone, including maximal compression stress, modulus of elasticity and bone mineral ash content of subchondral bone cores (from the graft centre and surrounding host bone). Results No significant differences were found in the mechanical properties of the subchondral bone under the graft, but there were significant changes in surrounding bone. Bone surrounding the grafts that were snap-frozen or frozen without DMSO was significantly stronger than the normal control bone. However, bone surrounding fresh autografts and cryoprotected allografts was not significantly different from normal control bone. Conclusions The changes in the mechanical behaviour of the host bone may be associated with graft cell viability. The greater stiffness of the subchondral host bone may have consequences for long-term graft integrity and for the development of degenerative osteoarthritis. PMID:9627549

  19. Osteochondritis Dissecans Involving the Trochlear Groove Treated With Retrograde Drilling

    PubMed Central

    Kaji, Yoshio; Nakamura, Osamu; Yamaguchi, Konosuke; Yamamoto, Tetsuji

    2015-01-01

    Abstract Osteochondritis dissecans (OCD) occurs frequently in the humeral capitellum of the upper extremity, whereas OCD involving the trochlear groove (trochlear groove OCD) is rarely reported. A standard treatment for trochlear groove OCD has therefore not been determined, although several methods have been tried. The case of a 14-year-old male gymnast with bilateral trochlear groove OCD is presented. Retrograde drilling from the lateral condyle of the humerus was applied for the OCD lesion of the left elbow, since it was larger in size than that in the right elbow and was symptomatic. Conversely, since the right lesion was small and asymptomatic, it was managed conservatively. After treatment, consolidation of the OCD lesions was observed in both elbows. However, the time to healing was shorter in the left elbow treated surgically than in the right elbow managed conservatively. In conclusion, retrograde drilling is a very simple and minimally invasive treatment. This case suggests that retrograde drilling for trochlear groove OCD may be a useful procedure that may accelerate the healing process for OCD lesions. PMID:26356703

  20. Challenges in engineering osteochondral tissue grafts with hierarchical structures.

    PubMed

    Gadjanski, Ivana; Vunjak-Novakovic, Gordana

    2015-01-01

    A major hurdle in treating osteochondral (OC) defects is the different healing abilities of two types of tissues involved - articular cartilage and subchondral bone. Biomimetic approaches to OC-construct engineering, based on recapitulation of biological principles of tissue development and regeneration, have potential for providing new treatments and advancing fundamental studies of OC tissue repair. This review on state of the art in hierarchical OC tissue graft engineering is focused on tissue engineering approaches designed to recapitulate the native milieu of cartilage and bone development. These biomimetic systems are discussed with relevance to bioreactor cultivation of clinically sized, anatomically shaped human cartilage/bone constructs with physiologic stratification and mechanical properties. The utility of engineered OC tissue constructs is evaluated for their use as grafts in regenerative medicine, and as high-fidelity models in biological research. A major challenge in engineering OC tissues is to generate a functionally integrated stratified cartilage-bone structure starting from one single population of mesenchymal cells, while incorporating perfusable vasculature into the bone, and in bone-cartilage interface. To this end, new generations of advanced scaffolds and bioreactors, implementation of mechanical loading regimens and harnessing of inflammatory responses of the host will likely drive the further progress.

  1. Results of Osteochondral Autologous Transplantation in the Knee

    PubMed Central

    Muller, Sandra; Breederveld, Roelf S.; Tuinebreijer, Wim E.

    2010-01-01

    Repair of full thickness defects of articular cartilage in the knee is difficult but important to prevent progression to osteoarthritis. The purpose of this retrospective study was to evaluate the clinical results of Osteochondral Autograft Transplant System (OATS) treatment for articular defects of the knee. Between 1999 and 2005, 15 knees (14 patients) were treated by the OATS technique. Age ranged from 27 to 52 years. Cartilage defects were up to 3.75 cm2. The mean follow-up was 42 months. Knee function was assessed by the Lysholmscore and International Knee Documentation Committee (IKDC) Subjective Knee Form. Six patients scored good or excellent. No patient had knee instability. Twelve of 13 patients returned to sports at an intermediate or high level. The subjective assessment score (0-10) changed from 4.7 before operation to 7.2 afterward (P=0.007). The OATS-technique resulted in a decrease in symptoms in patients with localized articular cartilage defects. We consider the OATS technique to be an appropriate treatment for cartilage defects to prevent progression of symptoms. PMID:20361003

  2. Hydrogen Supplementation of Preservation Solution Improves Viability of Osteochondral Grafts

    PubMed Central

    Yamada, Takuya; Onuma, Kenji; Kuzuno, Jun; Ujihira, Masanobu; Kurokawa, Ryosuke; Sakai, Rina; Takaso, Masashi

    2014-01-01

    Allogenic osteochondral tissue (OCT) is used for the treatment of large cartilage defects. Typically, OCTs collected during the disease-screening period are preserved at 4°C; however, the gradual reduction in cell viability during cold preservation adversely affects transplantation outcomes. Therefore, improved storage methods that maintain the cell viability of OCTs are needed to increase the availability of high-quality OCTs and improve treatment outcomes. Here, we evaluated whether long-term hydrogen delivery to preservation solution improved the viability of rat OCTs during cold preservation. Hydrogen-supplemented Dulbecco's Modified Eagles Medium (DMEM) and University of Wisconsin (UW) solution both significantly improved the cell viability of OCTs during preservation at 4°C for 21 days compared to nonsupplemented media. However, the long-term cold preservation of OCTs in DMEM containing hydrogen was associated with the most optimal maintenance of chondrocytes with respect to viability and morphology. Our findings demonstrate that OCTs preserved in DMEM supplemented with hydrogen are a promising material for the repair of large cartilage defects in the clinical setting. PMID:25506061

  3. Generation and characterization of osteochondral grafts with human nasal chondrocytes.

    PubMed

    Barandun, Marina; Iselin, Lukas Daniel; Santini, Francesco; Pansini, Michele; Scotti, Celeste; Baumhoer, Daniel; Bieri, Oliver; Studler, Ueli; Wirz, Dieter; Haug, Martin; Jakob, Marcel; Schaefer, Dirk Johannes; Martin, Ivan; Barbero, Andrea

    2015-08-01

    We investigated whether nasal chondrocytes (NC) can be used to generate composite constructs with properties necessary for the repair of osteochondral (OC) lesions, namely maturation, integration and capacity to recover from inflammatory burst. OC grafts were fabricated by combining engineered cartilage tissues (generated by culturing NC or articular chondrocytes - AC - onto Chondro-Gide® matrices) with devitalized spongiosa cylinders (Tutobone®). OC tissues were then exposed to IL-1β for three days and cultured for additional 2 weeks in the absence of IL-1β. Cartilage maturation extent was assessed (immune) histologically, biochemically and by delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) while cartilage/bone integration was assessed using a peel-off mechanical test. The use of NC as compared to AC allowed for more efficient cartilage matrix accumulation and superior integration of the cartilage/bone layers. dGEMRIC and biochemical analyzes of the OC constructs showed a reduced glycosaminoglycan (GAG) contents upon IL-1β administration. Cartilaginous matrix contents and integration forces returned to baseline up on withdrawal of IL-1β. By having a cartilage layer well developed and strongly integrated to the subchondral layer, OC tissues generated with NC may successfully engraft in an inflammatory post-surgery joint environment. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  4. The Wnt11 Signaling Pathway in Potential Cellular EMT and Osteochondral Differentiation Progression in Nephrolithiasis Formation.

    PubMed

    He, Deng; Lu, Yuchao; Hu, Henglong; Zhang, Jiaqiao; Qin, Baolong; Wang, Yufeng; Xing, Shuai; Xi, Qilin; Wang, Shaogang

    2015-07-17

    The molecular events leading to nephrolithiasis are extremely complex. Previous studies demonstrated that calcium and transforming growth factor-β1 (TGF-β1) may participate in the pathogenesis of stone formation, but the explicit mechanism has not been defined. Using a self-created genetic hypercalciuric stone-forming (GHS) rat model, we observed that the increased level of serous/uric TGF-β1 and elevated intracellular calcium in primary renal tubular epithelial cells (PRECs) was associated with nephrolithiasis progression in vivo. In the setting of high calcium plus high TGF-β1 in vitro, PRECs showed great potential epithelial to mesenchymal transition (EMT) progression and osteochondral differentiation properties, representing the multifarious increased mesenchymal and osteochondral phenotypes (Zeb1, Snail1, Col2A1, OPN, Sox9, Runx2) and decreased epithelial phenotypes (E-cadherin, CK19) bythe detection of mRNAs and corresponding proteins. Moreover, TGF-β-dependent Wnt11 knockdown and L-type Ca2+ channel blocker could greatly reverse EMT progression and osteochondral differentiation in PRECs. TGF-β1 alone could effectively promote EMT, but it had no effect on osteochondral differentiation in NRK cells (Rat kidney epithelial cell line). Stimulation with Ca2+ alone did not accelerate differentiation of NRK. Co-incubation of extracellular Ca2+ and TGF-β1 synergistically promotes EMT and osteochondral differentiation in NRK control cells. Our data supplied a novel view that the pathogenesis of calcium stone development may be associated with synergic effects of TGF-β1 and Ca2+, which promote EMT and osteochondral differentiation via Wnt11 and the L-type calcium channel.

  5. Citrate cross-linked gels with strain reversibility and viscoelastic behavior accelerate healing of osteochondral defects in a rabbit model.

    PubMed

    Ghosh, Paulomi; Rameshbabu, Arun Prabhu; Dhara, Santanu

    2014-07-22

    Most living tissues are viscoelastic in nature. Self-repair due to the dissipation of energy by reversible bonds prevents the rupture of the molecular backbone in these tissues. Recent studies, therefore, have aimed to synthesize biomaterials that approximate the mechanical performance of biological materials with self-recovery properties. We report an environmentally friendly method for the development of ionotropically cross-linked viscoelastic chitosan gels with a modulus comparable to that of living tissues. The strain recovery property was found to be highest for the gels with the lowest cross-linking density. The force-displacement curve showed significant hysteresis due to the presence of reversible bonds in the cross-linked gels. Nanoindentation studies demonstrated the creep phenomenon for the cross-linked chitosan gels. Creep, hysteresis, and plasticity index confirmed the viscoelastic behavior of the cross-linked gels. The viscoelastic gels were implanted at osteochondral defect sites to assess the tissue regeneration ability. In vivo results demonstrated early cartilage formation and woven bone deposition for defects filled with the gels compared to nontreated defects.

  6. Psychophysically based site selection coupled with dichotic stimulation improves speech recognition in noise with bilateral cochlear implants.

    PubMed

    Zhou, Ning; Pfingst, Bryan E

    2012-08-01

    The ability to perceive important features of electrical stimulation varies across stimulation sites within a multichannel implant. The aim of this study was to optimize speech processor MAPs for bilateral implant users by identifying and removing sites with poor psychophysical performance. The psychophysical assessment involved amplitude-modulation detection with and without a masker, and a channel interaction measure quantified as the elevation in modulation detection thresholds in the presence of the masker. Three experimental MAPs were created on an individual-subject basis using data from one of the three psychophysical measures. These experimental MAPs improved the mean psychophysical acuity across the electrode array and provided additional advantages such as increasing spatial separations between electrodes and/or preserving frequency resolution. All 8 subjects showed improved speech recognition in noise with one or more experimental MAPs over their everyday-use clinical MAP. For most subjects, phoneme and sentence recognition in noise were significantly improved by a dichotic experimental MAP that provided better mean psychophysical acuity, a balanced distribution of selected stimulation sites, and preserved frequency resolution. The site-selection strategies serve as useful tools for evaluating the importance of psychophysical acuities needed for good speech recognition in implant users.

  7. The Normandy field study on juvenile osteochondral conditions: conclusions regarding the influence of genetics, environmental conditions and management, and the effect on performance.

    PubMed

    van Weeren, P René; Denoix, Jean-Marie

    2013-07-01

    Juvenile osteochondral conditions (JOCC) have a major impact on the equine industry and include many musculoskeletal disorders of the young horse, of which osteochondrosis (OC) is the most prominent. The Breeding, Osteochondral Status and Athletic Career (BOSAC) project is the first large, comprehensive, longitudinal field study on the subject conducted in three breeds of performance horses (Thoroughbreds, Standardbred Trotters and Warmbloods) that were monitored in their natural environment where they were reared under common field conditions. The BOSAC study used a radiographic protocol designed for field use coupled to an internally validated severity scoring system, providing weighted radiographic findings as the primary outcome measure. The natural courses of various JOCC appear to differ, according to the joint and condition involved. Genetically, there were also large differences with moderate heritabilities in the tarsocrural and metacarpophalangeal/metatarsophalangeal joints and virtually no heritability for femoropatellar OC. There was a strong influence of exercise history (as an environmental condition) on the manifestation and natural course of JOCC. In the younger age class (<6months) lack of exercise or irregular exercise had a negative effect, as had exposure to excessive exercise. In the yearling category, (exercise-associated) intrinsic trauma seemed to be the most important negative factor. In terms of later function, the association of a poor radiographic score with poorer performance in racing Trotters could be demonstrated. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Juvenile Osteochondritis Dissecans of the Knee. About A Case

    PubMed Central

    Astore, Ignacio; Agotegaray, Juan Ignacio; Comba, Ignacio; Bisiach, Luciana

    2017-01-01

    Introduction: Juvenile osteochondritis dissecans is a pathology that affects the superficial articular cartilage and subchondral bone in patients with open physes. Treatment of this disease is based on patient’s age and the stage of the disease. Methods: 16-year-old patient, athlete, with a history of knee pain on the right side of acute onset, without traumatic history. A physical examination shows pain in the external compartment of the knee. MRI shows a stable lesion that involves the external femoral condyle, over a posterior area of 16 mm by 20mm. Crutches are indicate for walking without body burden. Symptoms continue for six months and there are no changes in MRI. It is decided to do a stabilization with a Herbert type screw. After the surgery, pain persists and in x-ray controls, osteointegration is not observed. Osteosynthesis material is extracted and mosaicplasty is performed. We used Guhl’s intraoperative classification. Results: In this case, for a young patient with Guhl’s lesion type III, the reduction with a Herbert type screw was indicated, as the lesion was stable, of a significant size and congruent. Lesion progressed to type IV in 6 months. Thus, mosaicplasty was performed, obtaining a good functional result according to the physical exam, with a complete range of flexion and extension. A second-look arthroscopic assessment was carried out 2 months after surgery, showing osteointegration and stability of the allogenic graft. Conclusion: The variable of stability of the fragment is very important when determining the treatment. Most of the stable lesions can be successfully treated with a conservative treatment. Also, it has been demonstrated that young patients have a higher rate of healing. Instead, unstable lesions require surgical treatment.

  9. The Impact of Weight on Arthroscopic Osteochondral Talar Reconstruction.

    PubMed

    Usuelli, Federico Giuseppe; Maccario, Camilla; Ursino, Chiara; Serra, Nicola; D'Ambrosi, Riccardo

    2017-06-01

    The purpose of the study was to assess the functional and radiologic outcomes after AT-AMIC (arthroscopic talus autologous matrix-induced chondrogenesis) in 2 weight groups of patients with osteochondral lesions of the talus (OLTs): patients with BMI <25 (Healthy Weight Group [HG]) and with BMI ≥25 (Overweight Group [OG]). Thirty-seven patients were evaluated. HG was composed of 21 patients (BMI = 21.90 ± 1.94), whereas OG consisted of 16 patients (BMI = 27.41 ± 1.98). All patients were treated with AT-AMIC repair for OLTs. Magnetic resonance imaging (MRI), computed tomography (CT), Visual Analgoue Scale (VAS) for pain, American Orthopaedic Foot & Ankle Society (AOFAS) Ankle and Hindfoot score and Short-Form Health Survey (SF-12) were administered preoperatively (T0) and at 6 (T1), 12 (T2), and 24 (T3) months postoperatively. In both groups, we found a significant difference for clinical and radiologic parameters with analysis of variance for repeated measures through 4 time points ( P < .001). In HG, AOFAS increased at every follow-up ( P < .05), whereas in OG, AOFAS improved only between T2 and T3 ( P = .0104). In OG we found a significant difference comparing CT and MRI at each follow-up; in HG this difference was found only at T0 ( P < .0001) and T1 ( P = .0492). Finally, OG presented a significantly larger lesion measured with MRI at T0 ( P = .033). OLTs in overweight patients were characterized by a larger preoperative size. At final follow-up, both groups showed a significant clinical improvement. AT-AMIC can be considered a safe and reliable procedure, regardless of weight, with a significant improvement also in quality of life. Level III, comparative study.

  10. The Augmentation of a Collagen/Glycosaminoglycan Biphasic Osteochondral Scaffold with Platelet-Rich Plasma and Concentrated Bone Marrow Aspirate for Osteochondral Defect Repair in Sheep

    PubMed Central

    Henson, Frances; Skelton, Carrie; Herrera, Emilio; Brooks, Roger; Fortier, Lisa A.; Rushton, Neil

    2012-01-01

    Objective: This study investigates the combination of platelet-rich plasma (PRP) or concentrated bone marrow aspirate (CBMA) with a biphasic collagen/glycosaminoglycan (GAG) osteochondral scaffold for the treatment of osteochondral defects in sheep. Design: Acute osteochondral defects were created in the medial femoral condyle (MFC) and the lateral trochlea sulcus (LTS) of 24 sheep (n = 6). Defects were left empty or filled with a 6 × 6-mm scaffold, either on its own or in combination with PRP or CBMA. Outcome measures at 6 months included mechanical testing, International Cartilage Repair Society (ICRS) repair score, modified O’Driscoll histology score, qualitative histology, and immunohistochemistry for type I, II, and VI collagen. Results: No differences in mechanical properties, ICRS repair score, or modified O’Driscoll score were detected between the 4 groups. However, qualitative assessments of the histological architecture, Safranin O content, and collagen immunohistochemistry indicated that in the PRP/scaffold groups, there was a more hyaline cartilage–like tissue repair. In addition, the addition of CBMA and PRP to the scaffold reduced cyst formation in the subchondral bone of healed lesions. Conclusion: There was more hyaline cartilage–like tissue formed in the PRP/scaffold group and less subchondral cystic lesion formation in the CBMA and PRP/scaffold groups, although there were no quantitative differences in the repair tissue formed. PMID:26069645

  11. Osteochondral lesion depth on MRI can help predict the need for a sandwich procedure.

    PubMed

    Nizak, R; Bekkers, J; de Jong, P A; Witkamp, T; Luijkx, T; Saris, D

    2017-05-01

    Autologous subchondral bone grafting in combination with autologous chondrocyte implantation (ACI) (sandwich procedure) is a well-accepted procedure for the treatment of osteochondral lesions of the knee. This requires a different surgical technique and preoperative planning compared to ACI alone. In addition, pain from bone marrow donor site locations can be expected and should be part of patient consent and expectations. This study evaluates whether the MRI made as part of the standard preoperative cartilage patient work up has the diagnostic accuracy to predict the need for a sandwich procedure. Retrospectively, 185 preoperative MRI scans (PD and T2 sequences) of patients planned for ACI were included. The integrity of the subchondral bone and lamina was scored by four different observers (3 radiologists, and 1 orthopaedic resident). The depth of the defect was measured perpendicular from articulating surface to the bottom of the bony lesion. The area under the curve (AUC) for subchondral defect on MRI (i.e. lamina or bone defect or expert impression), depth measurements and eventual sandwich procedure were calculated. Also inter-observer Kappa values were determined. The AUCs for lamina (0.74-0.80) and bone defect (0.73-0.79) were fair and inter-observer Kappas ranged from 0.49 to 0.76, indicating a moderate-good inter-observer agreement and moderate prediction of the need for a sandwich procedure based on the presence of lamina and or subchondral bone defect on MRI. However, depth measurements resulted in an AUC of 0.90 (95% CI: 0.84-0.95,) with an optimal cut-off point at 6.5mm depth of the lesion (90% sensitivity, 80% specificity) to predict the need for a sandwich procedure. Ours is the first study examining MRI as a diagnostic tool in predicting the need for a sandwich procedure. Our results show that the integrity of the subchondral layer on MRI has a moderate role in predicting the need for an eventual autologous bone graft to augment ACI whereas in our

  12. Treatment of juvenile osteochondritis dissecans of the talus: current concepts review

    PubMed Central

    VANNINI, FRANCESCA; CAVALLO, MARCO; BALDASSARRI, MATTEO; CASTAGNINI, FRANCESCO; OLIVIERI, ALESSANDRA; FERRANTI, ENRICO; BUDA, ROBERTO; GIANNINI, SANDRO

    2014-01-01

    Juvenile osteochondritis dissecans of the talus (JODT) affects the subchondral bone primarily and, in a skeletally immature population, articular cartilage secondarily. It probably consists of aseptic bone necrosis whose spontaneous healing is impaired by microtraumas, resulting in an osteochondral injury and, in some cases, in osteoarthritis. In many cases the clinical presentation is asymptomatic. Mild chronic pain is frequent, sometimes accompanied by swelling, stiffness or locking. Few data are currently available on this topic and, moreover, most existing data were obtained from mixed groups and populations; it is therefore difficult to outline a scheme for the treatment of JODT. However, the most suitable treatment in the first stages of the disease is conservative. The presence of a loose body is an indication for surgical fixation, drilling or regenerative procedures, depending on the presence/extent of subchondral bone sclerosis and the surgeon’s experience. Drilling has been shown to promote the healing of lesions with minimal surgical trauma. Microfractures, since they induce fibrocartilage repair, are to be considered only for small injuries. Mosaicplasty and osteochondral autograft transplantation may cause donor site morbidity and are techniques little reported in JODT. Regenerative techniques and fresh allografts give good results in osteochondral lesions, but further studies are required to describe the results that can be obtained in JODT alone. PMID:25750908

  13. Treatment of juvenile osteochondritis dissecans of the talus: current concepts review.

    PubMed

    Vannini, Francesca; Cavallo, Marco; Baldassarri, Matteo; Castagnini, Francesco; Olivieri, Alessandra; Ferranti, Enrico; Buda, Roberto; Giannini, Sandro

    2014-01-01

    Juvenile osteochondritis dissecans of the talus (JODT) affects the subchondral bone primarily and, in a skeletally immature population, articular cartilage secondarily. It probably consists of aseptic bone necrosis whose spontaneous healing is impaired by microtraumas, resulting in an osteochondral injury and, in some cases, in osteoarthritis. In many cases the clinical presentation is asymptomatic. Mild chronic pain is frequent, sometimes accompanied by swelling, stiffness or locking. Few data are currently available on this topic and, moreover, most existing data were obtained from mixed groups and populations; it is therefore difficult to outline a scheme for the treatment of JODT. However, the most suitable treatment in the first stages of the disease is conservative. The presence of a loose body is an indication for surgical fixation, drilling or regenerative procedures, depending on the presence/extent of subchondral bone sclerosis and the surgeon's experience. Drilling has been shown to promote the healing of lesions with minimal surgical trauma. Microfractures, since they induce fibrocartilage repair, are to be considered only for small injuries. Mosaicplasty and osteochondral autograft transplantation may cause donor site morbidity and are techniques little reported in JODT. Regenerative techniques and fresh allografts give good results in osteochondral lesions, but further studies are required to describe the results that can be obtained in JODT alone.

  14. Is retrograde drilling really useful for osteochondral lesion of talus with subchondral cyst?

    PubMed Central

    Jeong, Seong-Yup; Kim, Jong-Kil; Lee, Kwang-Bok

    2016-01-01

    Abstract Rationale: Retrograde drilling is a well accepted procedure for osteochondral lesion of the talus and subchondral cyst with intact overlying cartilage. It has good results in most reports. Compared to anterograde drilling, retrograde drilling can protect the integrity of the articular cartilage. The purpose of this study was to evaluate the suitability of using retrograde drilling for osteochondral lesion with subchondral cyst and discuss the mechanism involved in the development of subchondral cyst. Patient concerns: We report a 53-year-old man who had complained left ankle pain that lasted over 6 months which was exacerbated by walking. Diagnoses: We diagnosed it as osteochondral lesion of the talus with subchondral cyst. Interventions: Plain X-ray, computed tomography, and magnetic resonance imaging (MRI) of the ankle. Outcomes: He undertook retrograde drilling without debridement of cartilage. After the surgery, the pain had been subsided for 1 year, although arthritic change had progressed. However, after 5 years of retrograde drilling, he revisited our hospital due to severe ankle pain. Plain X-ray and MRI showed arthritic change of the ankle and multiple cystic formation of talus. Lessons: Retrograde drilling has some problem because this procedure is not theoretically correct when the development of a subchondral cyst in osteochondral lesion of the talus is considered. In addition, retrograde drilling may impair uninjured bone marrow of the talus, resulting in the development of multiple cystic formations. PMID:27930520

  15. A cadaveric analysis of contact stress restoration after osteochondral transplantation of a cylindrical cartilage defect.

    PubMed

    Kock, Niels B; Smolders, José M H; van Susante, Job L C; Buma, Pieter; van Kampen, Albert; Verdonschot, Nico

    2008-05-01

    Osteochondral transplantation is a successful treatment for full-thickness cartilage defects, which without treatment would lead to early osteoarthritis. Restoration of surface congruency and stability of the reconstruction may be jeopardized by early mobilization. To investigate the biomechanical effectiveness of osteochondral transplantation, we performed a standardized osteochondral transplantation in eight intact human cadaver knees, using three cylindrical plugs on a full-thickness cartilage defect, bottomed on one condyle, unbottomed on the contralateral condyle. Surface pressure measurements with Tekscan pressure transducers were performed after five conditions. In the presence of a defect the border contact pressure of the articular cartilage defect significantly increased to 192% as compared to the initially intact joint surface. This was partially restored with osteochondral transplantation (mosaicplasty), as the rim stress subsequently decreased to 135% of the preoperative value. Following weight bearing motion two out of eight unbottomed mosaicplasties showed subsidence of the plugs according to Tekscan measurements. This study demonstrates that a three-plug mosaicplasty is effective in restoring the increased border contact pressure of a cartilage defect, which may postpone the development of early osteoarthritis. Unbottomed mosaicplasties may be more susceptible for subsidence below flush level after (unintended) weight bearing motion.

  16. Arthroscopic treatment of osteochondritis dissecans of the capitellum: Report of 5 female athletes.

    PubMed

    Krijnen, Matthijs R; Lim, Liesbeth; Willems, W Jaap

    2003-02-01

    The management of osteochondritis dissecans of the capitellum of the adolescent elbow is still controversial. We report on 5 cases of female high-level athletes aged from 10 to 19 years (4 gymnasts, 1 waterpolo player). All these athletes had a symptomatic osteochondritis dissecans of the capitellum, which was treated arthroscopically in all cases. Follow-up time averaged 5 months (1 to 6.5 months). During the arthroscopy, loose osteochondral fragments of the capitellum and radial head were removed, and the defect was debrided. Thorough evaluation of the anterior and posterior joint including the olecranon fossa was performed. One of the 5 patients had a loose body requiring arthroscopic removal. Within 6 months after surgery, all except 1 elbow, the elbow with a loose body, regained maximum range of motion. Two patients returned to a high level of gymnastics and 1 was considering return. The short-term results of this treatment suggest that arthroscopic debridement of the loose osteochondral fragments provides a good result.

  17. Bilateral osteochondritis dissecans of the elbow treated by Herbert screw fixation.

    PubMed Central

    Inoue, G

    1991-01-01

    The case of a 15-year-old boy, a high-performance motocross rider, who developed bilateral osteochondritis dissecans of the elbow is described. Both lesions were successfully treated by Herbert screw internal fixation. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:1777781

  18. Is retrograde drilling really useful for osteochondral lesion of talus with subchondral cyst?: A case report.

    PubMed

    Jeong, Seong-Yup; Kim, Jong-Kil; Lee, Kwang-Bok

    2016-12-01

    Retrograde drilling is a well accepted procedure for osteochondral lesion of the talus and subchondral cyst with intact overlying cartilage. It has good results in most reports. Compared to anterograde drilling, retrograde drilling can protect the integrity of the articular cartilage. The purpose of this study was to evaluate the suitability of using retrograde drilling for osteochondral lesion with subchondral cyst and discuss the mechanism involved in the development of subchondral cyst. We report a 53-year-old man who had complained left ankle pain that lasted over 6 months which was exacerbated by walking. We diagnosed it as osteochondral lesion of the talus with subchondral cyst. Plain X-ray, computed tomography, and magnetic resonance imaging (MRI) of the ankle. He undertook retrograde drilling without debridement of cartilage. After the surgery, the pain had been subsided for 1 year, although arthritic change had progressed. However, after 5 years of retrograde drilling, he revisited our hospital due to severe ankle pain. Plain X-ray and MRI showed arthritic change of the ankle and multiple cystic formation of talus. Retrograde drilling has some problem because this procedure is not theoretically correct when the development of a subchondral cyst in osteochondral lesion of the talus is considered. In addition, retrograde drilling may impair uninjured bone marrow of the talus, resulting in the development of multiple cystic formations.

  19. Fixation of osteochondral fragments in the human knee using Meniscus Arrows.

    PubMed

    Wouters, Diederick B; Burgerhof, Johannes G M; de Hosson, Jeff T M; Bos, Rudolf R M

    2011-02-01

    The aim of this study is to compare the hold in bone of Meniscus Arrows and Smart Nails, followed by the report of the results of the clinical application of Meniscus Arrows as fixation devices. First, pull-out tests were performed to analyse the holdfast of both nails in bone. Statistical analysis showed no significant difference; therefore, the thinner Meniscus Arrow was chosen as fixation device in the patient series of two patients with a symptomatic Osteochondritis dissecans fragment and three patients with an osteochondral fracture of a femur condyle. The cartilage margins were glued with Tissuecoll. All fragments consolidated. Second look arthroscopy in three patients showed fixed fragments with stable, congruent cartilage edges. At an average follow-up period of 5 years no pain, effusion, locking, restricted range of motion or signs of osteoarthritis were reported. Based on the results of the pull-out tests and available clinical studies, Meniscus Arrows and Smart Nails are both likely to perform adequately as fixation devices in the treatment of Osteochondritis dissecans and osteochondral fractures in the knee. They both provide the advantage of one stage surgery. However, based on their smaller diameter, the Meniscus Arrows should be preferred for this indication.

  20. Design of a multiphase osteochondral scaffold. I. Control of chemical composition.

    PubMed

    Lynn, Andrew K; Best, Serena M; Cameron, Ruth E; Harley, Brendan A; Yannas, Ioannis V; Gibson, Lorna J; Bonfield, William

    2010-03-01

    This is the first in a series of articles that describe the design and development of a family of osteochondral scaffolds based on collagen-glycosaminoglycan (collagen-GAG) and calcium phosphate technologies, engineered for the regenerative repair of defects in articular cartilage. The osteochondral scaffolds consist of two layers: a mineralized type I collagen-GAG scaffold designed to regenerate the underlying subchondral bone and a nonmineralized type II collagen-GAG scaffold designed to regenerate cartilage. The subsequent articles in this series describe the fabrication and properties of a mineralized scaffold as well as a two-layer (one mineralized, the other not) osteochondral scaffold for regeneration of the underlying bone and cartilage, respectively. This article describes a technology through which the chemical composition-particularly the calcium phosphate mass fraction-of triple coprecipitated nanocomposites of collagen, glycosaminoglycan, and calcium phosphate can be accurately and reproducibly varied without the need for titrants or other additives. Here, we describe how the mineral:organic ratio can be altered over a range that includes that for articular cartilage (0 wt % mineral) and for bone (75 wt % mineral). This technology achieves the objective of mimicking the composition of two main tissue types found in articular joints, with particular emphasis on the osseous compartment of an osteochondral scaffold. Exclusion of titrants avoids the formation of potentially harmful contaminant phases during freeze-drying steps crucial for scaffold fabrication, ensuring that the potential for binding growth factors and drugs is maintained.

  1. Cement Casting to Optimize Reconstruction of Chronic Osteochondral Lesions of the Talus.

    PubMed

    Pulgar, Jorge; Escudero, Mario; Carcuro, Giovanni; Schiff, Adam; Pellegrini, Manuel

    2017-08-01

    Few surgical techniques have been described for reconstruction in massive osteochondral lesions of the talus, and there is limited evidence of techniques for accurately reproducing native talar anatomy with bone auto/allograft techniques. In this article, we present a novel technique, which is highly reproducible, using bone cement to restore the congruence and anatomy of the ankle joint. Level V: Technical tip.

  2. Chondrocyte viability in fresh and frozen large human osteochondral allografts: effect of cryoprotective agents.

    PubMed

    Judas, F; Rosa, S; Teixeira, L; Lopes, C; Ferreira Mendes, A

    2007-10-01

    Chondrocyte survival is a major goal for the effective storage and clinical performance of human osteochondral allografts. The majority of animal and human cryopreservation studies conducted so far have been performed in small osteochondral cylinders. Using human tibial plateaus as a model for large osteochondral pieces, this work sought to evaluate the cryoprotective efficiency of glycerol and dimethylsulfoxide (DMSO), and to identify cryopreservation conditions suitable for use in tissue banks. Human tibial plateaus harvested from 7 cadaveric tissue donors were incubated in the presence or absence of cryoprotective agents (CPA): 10% or 15% glycerol and 10% DMSO in a Ham F-12 nutrient mixture. Chondrocyte viability was assessed immediately after thawing, using the MTT reduction assay and a fluorescence microscopic method. The tibial plateaus frozen in the absence of CPA showed a significant decrease in chondrocyte viability. The use of CPA significantly increased chondrocyte viability compared with cartilage frozen without CPA (nearly 50% versus 80% living chondrocytes with 10% glycerol versus 10% DMSO, respectively) relative to that in fresh cartilage. In this regard, 10% DMSO was slightly more effective than either 10% or 15% glycerol, eliciting the recovery of approximately 15% relative to the living chondrocyte content in fresh cartilage. In all conditions, fluorescence microscopic studies showed that surviving chondrocytes were restricted to the superficial cartilage layer. Human tibial plateaus seemed to be a good experimental model to establish cryopreservation methods applicable to large human osteochondral pieces in tissue banks.

  3. Faster phonological processing and right occipito-temporal coupling in deaf adults signal poor cochlear implant outcome

    PubMed Central

    Lazard, Diane S.; Giraud, Anne-Lise

    2017-01-01

    The outcome of adult cochlear implantation is predicted positively by the involvement of visual cortex in speech processing, and negatively by the cross-modal recruitment of the right temporal cortex during and after deafness. How these two neurofunctional predictors concur to modulate cochlear implant (CI) performance remains unclear. In this fMRI study, we explore the joint involvement of occipital and right hemisphere regions in a visual-based phonological task in post-lingual deafness. Intriguingly, we show that some deaf subjects perform faster than controls. This behavioural effect is associated with reorganized connectivity across bilateral visual, right temporal and left inferior frontal cortices, but with poor CI outcome. Conversely, preserved normal-range reaction times are associated with left-lateralized phonological processing and good CI outcome. These results suggest that following deafness, involvement of visual cortex in the context of reorganized right-lateralized phonological processing compromises its availability for audio-visual synergy during adaptation to CI. PMID:28348400

  4. Blocking of tumor necrosis factor activity promotes natural repair of osteochondral defects in rabbit knee

    PubMed Central

    2009-01-01

    Background and purpose Osteochondral defects have a limited capacity for repair. We therefore investigated the effects of tumor necrosis factor (TNF) signal blockade by etanercept (human recombinant soluble TNF receptor) on the repair of osteochondral defects in rabbit knees. Material and methods Osteochondral defects (5 mm in diameter) were created in the femoral patellar groove in rabbits. Soon after the procedure, a first subcutaneous injection of etanercept was performed. This single injection or, alternatively, 4 injections in total (twice a week for 2 weeks) were given. Each of these 2 groups was divided further into 3 subgroups: a low-dose group (0.05 μg/kg), an intermediate-dose group (0.4 μ g/kg), and a high-dose group (1.6 μ g /kg) with 19 rabbits in each. As a control, 19 rabbits were injected with water alone. The rabbits in each subgroup were killed 4 weeks (6 rabbits), 8 weeks (6 rabbits), or 24 weeks (7 rabbits) after surgery and repair was assessed histologically. Results Histological examination revealed that the natural process of repair of the osteochondral defects was promoted by 4 subcutaneous injections of intermediate-dose etanercept and by 1 or 4 injections of high-dose etanercept at the various time points examined postoperatively (4, 8, and 24 weeks). Western blot showed that rabbit TNFα had a high affinity for etanercept. Interpretation Blocking of TNF by etanercept enabled repair of osteochondral defects in rabbit knee. Anti-TNF therapy could be a strategy for the use of tissue engineering for bone and cartilage repair. PMID:19916697

  5. Effects of triamcinolone acetonide on an in vivo equine osteochondral fragment exercise model.

    PubMed

    Frisbie, D D; Kawcak, C E; Trotter, G W; Powers, B E; Walton, R M; McIlwraith, C W

    1997-09-01

    The objective of this study was to determine the effects of intra-articularly administered triamcinolone acetonide (TA) in exercised equine athletes with carpal osteochondral fragmentation. Eighteen horses were randomly assigned to each of 3 groups. An osteochondral chip fragment was created in one randomly chosen intercarpal joint of each horse. Both intercarpal joints in the placebo control group (CNT) horses were injected with intra-articular administration (IA) of polyionic fluid. Both joints in the TA control group (TA CNT) horses were treated with 12 mg of TA in the intercarpal joint without an osteochondral fragment, and the opposite intercarpal joint was injected with a similar volume of polyionic fluid. The TA treated group (TA TX) horses were treated with 12 mg of TA in the joint that contained the osteochondral fragment and the opposite intercarpal joint was injected with a similar volume of polyionic fluid. All horses were treated IA on days 13 and 27 after surgery and exercised on a high speed treadmill for 6 weeks starting on Day 14. Horses in the TA TX group were significantly less lame than horses in the CNT and TA CNT groups. Horses in either TA CNT or TA TX groups had lower total protein, and higher hyaluronan, and glycosaminoglycan concentrations in synovial fluid than did those in the CNT group. Synovial membrane collected from subjects in TA CNT and TA TX groups had significantly less inflammatory cell infiltration, subintimal hyperplasia and subintimal fibrosis compared to the CNT group. Articular cartilage histomorphological parameters were significantly better from the TA CNT and TA TX groups compared to the CNT group. In conclusions, results from this study support favourable effects of TA on degree of clinically detectable lameness, and on synovial fluid, synovial membrane, and articular cartilage morphological parameters, both with direct intra-articular administration and remote site administration as compared to placebo treatment. The

  6. Development of Novel Three-Dimensional Printed Scaffolds for Osteochondral Regeneration

    PubMed Central

    Holmes, Benjamin; Zhu, Wei; Li, Jiaoyan; Lee, James D.

    2015-01-01

    As modern medicine advances, various methodologies are being explored and developed in order to treat severe osteochondral defects in joints. However, it is still very challenging to cure the osteochondral defects due to their poor inherent regenerative capacity, complex stratified architecture, and disparate biomechanical properties. The objective of this study is to create novel three-dimensional (3D) printed osteochondral scaffolds with both excellent interfacial mechanical properties and biocompatibility for facilitating human bone marrow mesenchymal stem cell (MSC) growth and chondrogenic differentiation. For this purpose, we designed and 3D printed a series of innovative bi-phasic 3D models that mimic the osteochondral region of articulate joints. Our mechanical testing results showed that our bi-phasic scaffolds with key structures have enhanced mechanical characteristics in compression (a maximum Young's modulus of 31 MPa) and shear (a maximum fracture strength of 5768 N/mm2) when compared with homogenous designs. These results are also correlated with numerical simulation. In order to improve their biocompatibility, the scaffolds' surfaces were further modified with acetylated collagen (one of the main components in osteochondral extracellular matrix). MSC proliferation results demonstrated that incorporation of a collagen, along with biomimetically designed micro-features, can greatly enhance MSC growth after 5 days in vitro. Two weeks' chondrogenic differentiation results showed that our novel scaffolds (dubbed “key” scaffolds), both with and without surface collagen modification, displayed enhanced chondrogenesis (e.g., 130%, 114%, and 236% increases in glycosaminoglycan, type II collagen deposition, and total protein content on collagen-modified key scaffolds when compared with homogeneous controls). PMID:25088966

  7. Open mosaicplasty in osteochondral lesions of the talus: a prospective study.

    PubMed

    Emre, Tuluhan Yunus; Ege, Tolga; Cift, Hakan Turan; Demircioğlu, Demet Tekdöş; Seyhan, Bahadir; Uzun, Macit

    2012-01-01

    Osteochondral lesions of the talus present with symptoms of pain and painful motion, affecting the quality of the patient's daily life. We evaluated the 2-year short-term outcomes of patients whose large osteochondral lesions of the talus were treated with medial malleolar osteotomy and a mosaic graft harvested from the knee on the same side. A total of 32 patients who had cartilage lesions due to osteochondritis dissecans in the medial aspect of the talus underwent mosaicplasty after medial malleolar osteotomy. The patients were followed up for a mean period of 16.8 (range 12 to 24) months. The staging and treatment plan of the osteochondral lesions of the talus were made according to the Bristol classification. The follow-up protocol for the patients included direct radiography and magnetic resonance imaging. The American Orthopaedic Foot and Ankle Society scoring system was used to assess the patients during the pre- and postoperative periods. Of the 32 patients, 3 (9.4%) were female and 29 (90.6%) male, with a mean age of 27.5 (range 20 to 47) years. The mean preoperative American Orthopaedic Foot and Ankle Society score was 59.12 ± 7.72 but had increased to 87.94 ± 3.55 during the postoperative 2 years. The increase in American Orthopaedic Foot and Ankle Society score was statistically significant (p < .05). We have concluded that open mosaicplasty is a reliable and effective method for the treatment of osteochondral lesions with subchondral cyst formation in the talus, exceeding 1.5 cm in diameter.

  8. Scalable fabrication of coupled NV center - photonic crystal cavity systems by self-aligned N ion implantation

    DOE PAGES

    Schröder, T.; Walsh, M.; Zheng, J.; ...

    2017-04-06

    Towards building large-scale integrated photonic systems for quantum information processing, spatial and spectral alignment of single quantum systems to photonic nanocavities is required. In this paper, we demonstrate spatially targeted implantation of nitrogen vacancy (NV) centers into the mode maximum of 2-d diamond photonic crystal cavities with quality factors up to 8000, achieving an average of 1.1 ± 0.2 NVs per cavity. Nearly all NV-cavity systems have significant emission intensity enhancement, reaching a cavity-fed spectrally selective intensity enhancement, Fint, of up to 93. Although spatial NV-cavity overlap is nearly guaranteed within about 40 nm, spectral tuning of the NV’s zero-phonon-linemore » (ZPL) is still necessary after fabrication. To demonstrate spectral control, we temperature tune a cavity into an NV ZPL, yielding FZPLint~5 at cryogenic temperatures.« less

  9. Osteochondritis Dissecans of the Humeral Capitellum in Young Athletes

    PubMed Central

    Kajiyama, Shiro; Muroi, Satoshi; Sugaya, Hiroyuki; Takahashi, Norimasa; Matsuki, Keisuke; Kawai, Nobuaki; Osaki, Makoto

    2017-01-01

    Background: Osteochondritis dissecans (OCD) lesions are often observed in the humeral capitellum both in young baseball players and gymnasts. It is generally believed that capitellar OCD in baseball players can be seen on an anteroposterior (AP) radiograph with the elbow in 45° of flexion. However, the mechanism of injury seems to be different in baseball players and gymnasts. Repetitive valgus overload with the elbow in flexion is believed to be the cause of capitellar OCD lesions in baseball players, whereas weightbearing with the elbow in extension may be the cause of OCD in gymnasts. Purpose: To determine the difference in capitellar OCD location between baseball players and gymnasts and to propose the optimal AP radiographic angle of the elbow for visualization of early-stage OCD lesions in adolescent gymnasts. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Subjects consisted of 95 baseball players (95 elbows) and 21 gymnasts (24 elbows) with a mean age of 13.7 years (range, 11-18 years). To localize the lesion, inclination of the affected area in the humeral capitellum against the humeral axis was investigated using sagittal computed tomography images of the elbow. The inclination angle was defined as the angle between the long axis of the humerus and the line perpendicular to a line that connected the anterior and posterior margin of the lesion. The inclination angle in each group was compared and statistically analyzed. Results: The mean inclination angle was 57.6° ± 10.7° in baseball players and 28.0° ± 10.7° in gymnasts. Capitellar OCD lesions were located more anterior in baseball players when compared with gymnasts (P < .01). Conclusion: Due to differences in applied stress, capitellar OCD lesions in baseball players were located more anteriorly compared with those seen in gymnasts. Therefore, although AP radiographs with the elbow in 45° of flexion are optimal for detecting OCD lesions in baseball players, radiographs with

  10. Intra-articular osteoid osteoma of the lateral tibial plateau treated with arthroscopically assisted removal and retrograde osteochondral grafting.

    PubMed

    Adachi, Nobuo; Shimose, Shoji; Nakamae, Atsuo; Okuhara, Atsushi; Kamei, Goki; Ochi, Mitsuo

    2014-01-01

    The treatment of an intra-articular osteoid osteoma is sometimes challenging, because of its location. We report a patient with an intra-articular osteoid osteoma of the lateral tibial plateau which was excised under an arthroscopically assisted procedure. After total resection of the intra-articular osteoid osteoma, the osteochondral defect of the lateral tibial plateau was reconstructed with a retrograde autogenous osteochondral graft which was harvested from the non-weightbearing area of the distal femur.

  11. [Intra-osseous and intra-articular cyst of the knee. Apropos of a case associated with osteochondritis dissecans].

    PubMed

    Lootvoet, L; Himmer, O; Defourny, A; Hamels, J; Jaucot, J; Ghosez, J P

    1995-01-01

    Subchondral bone cyst, intraarticular synovial cyst, and osteochondritis dissecans arising together are analyzed: this association has so far not been reported. If we accept the theory of a mechanical origin for subchondral bone cysts (leakage of joint fluid or intrusion of the synovial membrane through a breach in the cartilage), then the osteochondritis certainly provided the port of entry that allowed formation of the intraosseous synovial cyst in this patient.

  12. Cochlear Implants

    MedlinePlus

    ... Medical Procedures Implants and Prosthetics Cochlear Implants Cochlear Implants Share Tweet Linkedin Pin it More sharing options ... normal ear, ear with hearing loss, and cochlear implant procedure Welcome to the Food and Drug Administration ( ...

  13. Autologous Osteochondral Transplantation for Osteochondral Lesions of the Talus: Does Previous Bone Marrow Stimulation Negatively Affect Clinical Outcome?

    PubMed

    Ross, Andrew W; Murawski, Christopher D; Fraser, Ethan J; Ross, Keir A; Do, Huong T; Deyer, Timothy W; Kennedy, John G

    2016-07-01

    To determine if functional outcomes and magnetic resonance imaging (MRI) outcomes were significantly different between patients receiving primary autologous osteochondral transplantation (AOT) and patients receiving secondary AOT surgery after failed microfracture. A group of 76 patients enrolled into the Foot and Ankle Service between 2006 and 2012 was retrospectively analyzed. Patient-reported outcomes were evaluated in 76 patients using the Foot and Ankle Outcome Score (FAOS). Superficial and deep tissues at the repaired defect site, as well as the adjacent normal cartilage, were analyzed using quantitative T2 mapping MRI. Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) allowed for morphological evaluation of the repair tissue. The mean clinical follow-up time was 51 ± 23 months (range, 12 to 97 months), and the mean MRI follow-up time was 26 months (range, 24 to 36 months). Twenty-two patients received primary AOT and 54 received secondary AOT after failed microfracture. Patient characteristics between groups were similar with regard to age, gender, lesion size, and follow-up time. The mean postoperative FAOS was 10 points higher in the primary AOT group (83.2 ± 17.0) compared with the secondary AOT group (72.4 ± 19.4) (P = .01). Regression analysis showed that secondary AOT patients preoperative to postoperative change in FAOS was 9 points lower than in primary AOT patients after adjustment for age, preoperative FAOS, and lesion size (P = .045). The mean MOCART score, superficial T2 and deep T2 values, and the difference between normal and repair cartilage T2 values were not significantly different between groups. Lesion size was negatively correlated with MOCART scores (ρ = -0.2, P = .04), but positively correlated with difference in T2 values between repair and adjacent normal cartilage in the superficial layer (ρ = 0.3, P = .045). Primary AOT shows better functional outcomes compared with secondary AOT after failed

  14. Two Patients with Osteochondral Injury of the Weight-Bearing Portion of the Lateral Femoral Condyle Associated with Lateral Dislocation of the Patella

    PubMed Central

    Inoue, Hiroaki; Atsumi, Satoru; Ichimaru, Shohei; Fujiwara, Hiroyoshi; Kubo, Toshikazu

    2014-01-01

    Complications of patellar dislocation include osteochondral injury of the lateral femoral condyle and patella. Most cases of osteochondral injury occur in the anterior region, which is the non-weight-bearing portion of the lateral femoral condyle. We describe two patients with osteochondral injury of the weight-bearing surface of the lateral femoral condyle associated with lateral dislocation of the patella. The patients were 18- and 11-year-old females. Osteochondral injury occurred on the weight-bearing surface distal to the lateral femoral condyle. The presence of a free osteochondral fragment and osteochondral injury of the lateral femoral condyle was confirmed on MRI and reconstruction CT scan. Treatment consisted of osteochondral fragment fixation or microfracture, as well as patellar stabilization. Osteochondral injury was present in the weight-bearing portion of the lateral femoral condyle in both patients, suggesting that the injury was caused by friction between the patella and lateral femoral condyle when the patella was dislocated or reduced at about 90° flexion of the knee joint. These findings indicate that patellar dislocation may occur and osteochondral injury may extend to the weight-bearing portion of the femur even in deep flexion, when the patella is stabilized on the bones of the femoral groove. PMID:25506015

  15. Comparative repair capacity of knee osteochondral defects using regenerated silk fiber scaffolds and fibrin glue with/without autologous chondrocytes during 36 weeks in rabbit model.

    PubMed

    Kazemnejad, Somaieh; Khanmohammadi, Manijeh; Mobini, Sahba; Taghizadeh-Jahed, Masoud; Khanjani, Sayeh; Arasteh, Shaghayegh; Golshahi, Hannaneh; Torkaman, Giti; Ravanbod, Roya; Heidari-Vala, Hamed; Moshiri, Ali; Tahmasebi, Mohammad-Naghi; Akhondi, Mohammad-Mehdi

    2016-06-01

    The reconstruction capability of osteochondral (OCD) defects using silk-based scaffolds has been demonstrated in a few studies. However, improvement in the mechanical properties of natural scaffolds is still challengeable. Here, we investigate the in vivo repair capacity of OCD defects using a novel Bombyx mori silk-based composite scaffold with great mechanical properties and porosity during 36 weeks. After evaluation of the in vivo biocompatibility and degradation rate of these scaffolds, we examined the effectiveness of these fabricated scaffolds accompanied with/without autologous chondrocytes in the repair of OCD lesions of rabbit knees after 12 and 36 weeks. Moreover, the efficiency of these scaffolds was compared with fibrin glue (FG) as a natural carrier of chondrocytes using parallel clinical, histopathological and mechanical examinations. The data on subcutaneous implantation in mice showed that the designed scaffolds have a suitable in vivo degradation rate and regenerative capacity. The repair ability of chondrocyte-seeded scaffolds was typically higher than the scaffolds alone. After 36 weeks of implantation, most parts of the defects reconstructed by chondrocytes-seeded silk scaffolds (SFC) were hyaline-like cartilage. However, spontaneous healing and filling with a scaffold alone did not eventuate in typical repair. We could not find significant differences between quantitative histopathological and mechanical data of SFC and FGC. The fabricated constructs consisting of regenerated silk fiber scaffolds and chondrocytes are safe and suitable for in vivo repair of OCD defects and promising for future clinical trial studies.

  16. Osteochondral lesions of the talus in the athlete: up to date review.

    PubMed

    Shimozono, Yoshiharu; Yasui, Youichi; Ross, Andrew W; Kennedy, John G

    2017-03-01

    Osteochondral lesions of the talus (OLT) are common injuries in athletes. The purpose of this study is to comprehensively review the clinical results and return to sport capacity in athletes following treatment for OLT. Reparative procedures, such as bone marrow stimulation, and replacement procedures, such as autologous osteochondral transplantation, provide good clinical outcomes in short- and mid-term follow-up in the athlete. Recently, biological augmentation and scaffold-based therapies have been shown to improve clinical and radiological outcomes in OLT in both the general population and athletes. Most studies are of a low level of evidence. Studies analyzing the return to sport capability in athletes are further lacking. High-level evidence and well-designed clinical trials are required to establish the most effective treatment protocol.

  17. Osteochondritis dessicans and subchondral cystic lesions in draft horses: a retrospective study.

    PubMed Central

    Riley, C B; Scott, W M; Caron, J P; Fretz, P B; Bailey, J V; Barber, S M

    1998-01-01

    The clinical features, radiographic findings, treatment, and outcome in 51 draft horses with osteochondritis dessicans (OCD) or subchondral cystic lesions (SC) are reported. Clydesdale and Percheron were the most commonly affected breeds, and affected animals represented only 5% of the hospital population of draft horses. Horses were most frequently affected in the tibiotarsal joints and 73% (24 of 33 cases) of the horses with tibiotarsal effusion were affected bilaterally. Osteochondritis dessicans of the distal intermediate ridge was the most common lesion found in the tibiotarsal joint. The stifle was also frequently affected; 87% (13 of 15 cases) of horses with femoropatellar OCD only were lame, and lesions were most commonly located on the lateral trochlear ridge. Sixteen cases were managed conservatively, 30 received surgery, and 5 were euthanized. Lameness, effusion, or both clinical signs resolved in more than 50% of surgically treated cases, but clinical signs improved in 30% of conservatively-managed cases. PMID:9789673

  18. Steroid-induced femoral head osteonecrosis in immune thrombocytopenia treatment with osteochondral autograft transplantation.

    PubMed

    Fotopoulos, Vasileios Ch; Mouzopoulos, George; Floros, Themistoklis; Tzurbakis, Matthaios

    2015-09-01

    Osteonecrosis of the femoral head is a devastating complication of steroid administration and has rarely been observed in the treatment of immune thrombocytopenia. The treatment of osteochondral defects in advanced stages of avascular necrosis (AVN), characterized by collapse of the subchondral bone, remains an unsolved burden in orthopedic surgery. In this report, we present a case of a 19-year-old female that was admitted in the Emergency Department with walking disability and painful hip joint movement due to steroid-induced femoral head osteonecrosis. Two years before she was diagnosed with immune thrombocytopenia, for which she received pulse steroid therapy with high dose of dexamethasone and underwent a splenectomy. This case report is the first to describe the use of osteochondral autograft transplantation as a treatment of steroid-induced AVN of the femoral head due to immune thrombocytopenia at the age of 19 years with very good clinical and radiological results 3 years postoperatively.

  19. Ion-implanted capacitively coupled silicon strip detectors with integrated polysilicon bias resistors processed on a 100 mm wafer

    NASA Astrophysics Data System (ADS)

    Hietanen, Iiro; Lindgren, Jukka; Orava, Risto; Tuuva, Tuure; Voutilainen, Martti; Brenner, Richard; Andersson, Mikael; Leinonen, Kari; Ronkainen, Hannu

    1991-12-01

    Double-sided silicon strip detectors with integrated coupling capacitors and polysilicon resistors have been processed on a 100 mm wafer. A detector with an active area of 19 × 19 mm 2 was connected to LSI readout electronics and tested. The strip pitch of the detector is 25 μm on the p-side and 50 μm on the n-side. The readout pitch is 50 μm on both sides. The number of readout strips is 774 and the total number of strips is 1161. On the p-side a signal-to-noise of 35 has been measured using a 90Sr β-source. The n-side has been studied using a laser.

  20. Osteochondritis Dissecans of the Humeral Head: A Case Report and Review of the Literature

    PubMed Central

    Jafari, Davod; Shariatzadeh, Hooman; Mazhar, Farid Najd; Okhovatpour, Mohammad Ali; Razavipour, Mehran

    2017-01-01

    Osteochondritis dissecans (OCD) is a common joint disorder in knee, ankle and elbow, however it can be rarely found in glenohumeral joint. In this study, we report an asymptomatic case of humeral head OCD, which was detected incidentally following a trauma. X-rays showed an area of lucency around an oval bony fragment measuring about 1 cm on the superior aspect of the humeral head. However, the patient was pain-free and the shoulder range of motion was normal. PMID:28271091

  1. Intra-articular osteoid osteoma at the femoral trochlea treated with osteochondral autograft transplantation.

    PubMed

    Leeman, Joshua J; Motamedi, Daria; Wildman-Tobriner, Ben; O'Donnell, Richard J; Link, Thomas M

    2016-06-01

    We present the case of an intra-articular osteoid osteoma at the femoral trochlea. Intra-articular osteoid osteoma can present a diagnostic challenge both clinically and with imaging because it presents differently from the classic cortical osteoid osteoma. Given the lesion's proximity to overlying cartilage, the patient underwent resection of the lesion with osteochondral autograft transplantation at the surgical defect. A comprehensive literature review and discussion of intra-articular osteoma will be provided.

  2. Percutaneous CT-Guided Treatment of Osteochondritis Dissecans of the Sacroiliac Joint

    SciTech Connect

    Becce, Fabio; Mouhsine, Elyazid; Mosimann, Pascal John; Anaye, Anass; Letovanec, Igor; Theumann, Nicolas

    2012-08-15

    Osteochondritis dissecans (OCD) is a joint disorder that affects the articular cartilage and subchondral bone, most commonly at the knee. OCD of the sacroiliac joint is extremely rare. Management of OCD remains controversial, and surgery is often needed, especially when conservative treatment fails. We present a rare case of OCD involving the left sacroiliac joint successfully treated by percutaneous computed tomography-guided retrograde drilling and debridement.

  3. Variation of Mesenchymal Cells in Polylactic Acid Scaffold in an Osteochondral Repair Model

    PubMed Central

    Oshima, Yasushi; Harwood, Frederick L.; Coutts, Richard D.; Kubo, Toshikazu

    2009-01-01

    Objective To achieve osteochondral regeneration utilizing transplantation of cartilage-lineage cells and adequate scaffolds, it is essential to characterize the behavior of transplanted cells in the repair process. The objectives of this study were to elucidate the survival of mesenchymal cells (MCs). In a polylactic acid (PLA) scaffold and assess the possibility of MC/PLA constructs for osteochondral repair. Design Bone marrow from mature male rabbits was cultured for 2 weeks, and fibroblast-like MCs, which contain mesenchymal stem cells (MSCs), were obtained. A cell/scaffold construct was prepared with one million MCs and a biodegradable PLA core using a rotator device. One week after culturing, the construct was transplanted into an osteochondral defect in the medial femoral condyle of female rabbits and the healing process examined histologically. To examine the survivability of transplanted MCs, the male-derived sex-determining region Y (SRY) gene was assessed as a marker of MCs in the defect by polymerase chain reaction (PCR). Results In the groups of defects without any treatment, and the transplantation of PLA without cells, the defects were not repaired with hyaline cartilage. The cartilaginous matrix by safranin O staining and type II collagen by immunohistochemical staining were recognized, however the PLA matrix was still present in the defects at 24 weeks after transplantation of the construct. During the time passage, transplanted MCs numbers decreased from 7.8 × 105 at 1 week, to 3.5 × 105 at 4 weeks, and to 3.8 × 104 at 12 weeks. Transplanted MCs were not detectable at 24 weeks. Conclusions MCs contribute to the osteochondral repair expressing the cartilaginous matrix, however the number of MCs were decreasing with time (i.e. 24 weeks). These results could be essential for achieving cartilage regeneration by cell transplantation strategies with growth factors and/or gene therapy. PMID:19231922

  4. Changes in condylar coefficient of friction after osteochondral graft transplantation and modulation with hyaluronan.

    PubMed

    Lane, John; Healey, Robert; Amiel, David

    2009-12-01

    To better understand the changes in the cartilage coefficient of friction (COF) after an osteochondral repair, an assessment of dynamic loads has been developed using a goat knee model. The application of hyaluronan (HA) was also assessed for its lubricative properties and the resulting COF of the knee after osteochondral repair. A total of 18 caprine knees were dissected and mounted into an Instron load frame (Instron, Norwood, MA) for testing. The COF was measured in 10 knees relative to the normal, unaltered joint and then calibrated to account for friction of the system. These experimental knees were tested in 5 modes: normal; empty 4.5-mm defect; and osteochondral repairs that were elevated, flush, or depressed relative to the cartilage surface. Saline solution lavage kept the knees moist during testing. The effect of HA was evaluated after mechanical testing. Eight knees were used to study the effect of lavage on the joints because of the significant increase in the COF that it produced. Whereas all modes increased the COF from normal levels, the most significant changes occurred when there was proud placement. Increases of 4 times the normal friction levels were measured. Increases in the COF were also associated with saline solution lavage (0.006 to 0.046). There was a significant reduction in friction after HA injection, which reduced the COF to near-normal levels. There is a significant increase in the COF associated with saline solution lavage and an osteochondral plug being left proud, which can be temporarily reduced with a lubricative material such as HA. Dramatic increases in the COF can potentially damage chondrocytes when the patient begins articulating the joint after surgery. Such injuries may affect the ability of the cartilage to heal fully. Reducing the elevated COF with lubricating materials, such as HA, is recommended based on the results of this study.

  5. Cell Magnetic Targeting System for Repair of Severe Chronic Osteochondral Defect in a Rabbit Model.

    PubMed

    Mahmoud, Elhussein Elbadry; Kamei, Goki; Harada, Yohei; Shimizu, Ryo; Kamei, Naosuke; Adachi, Nobuo; Misk, Nabil Ahmed; Ochi, Mitsuo

    The aim of this study was to investigate a cell delivery system for repair of severe chronic osteochondral defects using magnetically labeled mesenchymal stem cells (m-MSCs), with the aid of an external magnetic device, through the accumulation of a small number of m-MSCs into a desired area and to detect the suitable number of autologous m-MSCs needed for repair of the defect. Twenty-six male Japanese white rabbits aged 6 months were used. An osteochondral defect was created bilaterally at the weight-bearing surface of the medial femoral condyle of the rabbits' knees (3 mm diameter; 4 mm depth). At 4 weeks after creation of the defect, autogenic transplantation of the m-MSCs into the defect area was performed, followed by 10-min exposure to an external magnetic device, where animals were divided into four groups: high (1 × 10(6) m-MSCs), medium (2 × 10(5) m-MSCs), low (4 × 10(4) m-MSCs), and control (PBS injection). At 4 and 12 weeks posttransplantation of m-MSCs, repaired tissue was assessed histologically using the Fortier score with toluidine blue staining. Transplantation of a low number of m-MSCs was not enough to improve osteogenesis and chondrogenesis, but the medium and high groups improved repair of the chronic defect with chondrogenic tissues and showed histologically significantly better results than the control and low groups. The use of a magnetic targeting system for delivering m-MSCs has the potential to overcome the clinical hurdles for repair of the severe chronic osteochondral defect. Furthermore, this system is predicted to produce good clinical outcomes for humans, not only to repair osteochondral defects but also to repair a variety of damaged tissues.

  6. Stem cell-based microphysiological osteochondral system to model tissue response to interleukin-1β.

    PubMed

    Lin, Hang; Lozito, Thomas P; Alexander, Peter G; Gottardi, Riccardo; Tuan, Rocky S

    2014-07-07

    Osteoarthritis (OA) is a chronic degenerative disease of the articular joint that involves both bone and cartilage degenerative changes. An engineered osteochondral tissue within physiological conditions will be of significant utility in understanding the pathogenesis of OA and testing the efficacy of potential disease-modifying OA drugs (DMOADs). In this study, a multichamber bioreactor was fabricated and fitted into a microfluidic base. When the osteochondral construct is inserted, two chambers are formed on either side of the construct (top, chondral; bottom, osseous) that is supplied by different medium streams. These medium conduits are critical to create tissue-specific microenvironments in which chondral and osseous tissues will develop and mature. Human bone marrow stem cell (hBMSCs)-derived constructs were fabricated in situ and cultured within the bioreactor and induced to undergo spatially defined chondrogenic and osteogenic differentiation for 4 weeks in tissue-specific media. We observed tissue specific gene expression and matrix production as well as a basophilic interface suggesting a developing tidemark. Introduction of interleukin-1β (IL-1β) to either the chondral or osseous medium stream induced stronger degradative responses locally as well as in the opposing tissue type. For example, IL-1β treatment of the osseous compartment resulted in a strong catabolic response in the chondral layer as indicated by increased matrix metalloproteinase (MMP) expression and activity, and tissue-specific gene expression. This induction was greater than that seen with IL-1β application to the chondral component directly, indicative of active biochemical communication between the two tissue layers and supporting the osteochondral nature of OA. The microtissue culture system developed here offers novel capabilities for investigating the physiology of osteochondral tissue and pathogenic mechanisms of OA and serving as a high-throughput platform to test potential

  7. Intra-articular osteoid osteoma at the femoral trochlea treated with osteochondral autograft transplantation

    PubMed Central

    Leeman, Joshua J; Motamedi, Daria; Wildman-Tobriner, Ben; O’Donnell, Richard J; Link, Thomas M

    2016-01-01

    We present the case of an intra-articular osteoid osteoma at the femoral trochlea. Intra-articular osteoid osteoma can present a diagnostic challenge both clinically and with imaging because it presents differently from the classic cortical osteoid osteoma. Given the lesion’s proximity to overlying cartilage, the patient underwent resection of the lesion with osteochondral autograft transplantation at the surgical defect. A comprehensive literature review and discussion of intra-articular osteoma will be provided. PMID:27761182

  8. Osteochondral humeral head fracture after posterior shoulder subluxation: A case report

    PubMed Central

    Fandridis, Emmanouil; Stavropoulos, Spiros; Dimou, Leonidas; Spyridonos, Sarantis

    2014-01-01

    Traumatic posterior shoulder subluxations are rare entities which require clinical suspicion upon presentation. Although literature presents many sequels of posterior shoulder subluxations, we have not come across any shearing type osteochondral fracture in the literature. In this case report we present diagnosis, treatment and follow-up results of this rare fracture in a 26-year-old male following a fall from a motorcycle. PMID:25114417

  9. Traumatic proximal interphalangeal joint reconstruction with an autologous hemi-toe osteochondral graft: case report.

    PubMed

    Pirani, Asif A; Rao, Ajit; Sharma, Sheel

    2013-07-01

    We report a case of a traumatic proximal interphalangeal joint injury with loss of the middle phalangeal base and articular surface, which was reconstructed with an autologous hemi-toe osteochondral graft. The patient had a 72° improvement in proximal interphalangeal joint motion and excellent functional improvements. Postoperative computed tomography imaging indicated bony union and articular congruence. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  10. Osteochondral interface generation by rabbit bone marrow stromal cells and osteoblasts coculture.

    PubMed

    Chen, Kelei; Teh, Thomas Kok Hiong; Ravi, Sujata; Toh, Siew Lok; Goh, James Cho Hong

    2012-09-01

    Physiological osteochondral interface regeneration is a significant challenge. This study aims to investigate the effect of the coculture of chondrogenic rabbit bone marrow stromal cells (rBMSCs) with rabbit osteoblasts in a specially designed two-dimensional (2D)-three-dimensional (3D) co-interface culture to develop the intermediate osteochondral region in vitro. The 2D-3D coculture system was set up by first independently culturing chondrogenic rBMSCs on a scaffold and osteoblasts in cell culture plates, and subsequently placed in contact and cocultured. As control, samples not cocultured with osteoblasts were used. The regulatory effects exerted by osteoblasts on chondrogenic rBMSCs were quantified by real-time polymerase chain reaction. To study the effect of coculture on cells located in different parts of the scaffold, samples were separated into two parts and significantly different gene expression patterns were found between them. In comparison with the control group, a significant moderate downregulation of chondrogenic marker genes, such as Collagen II and Aggrecan was observed. However, the Sox-9 and Collagen I expression increased. More importantly, chondrogenic rBMSCs in the coculture system were shown to form the osteochondral interface layer by expressing calcified cartilage zone specific extracellular matrix marker Collagen X and the hypertrophic chondrocyte marker MMP-13, which were not observed in the control group. Specifically, only the chondrogenic rBMSC layer in contact with the osteoblasts expressed Collagen X and MMP-13, indicating the positive influence of the coculture upon interface formation. Biochemical analyses, histology results, and immunohistochemical staining further supported this observation. In conclusion, this study revealed that specific regulatory stimulations from osteoblasts in the 2D-3D interface coculture system could induce the formation of ostochondral interface for the purpose of osteochondral tissue engineering.

  11. [CLINICAL SIGNIFICANCE OF BIOMARKERS OF OSTEOCHONDRAL LESIONS IN EARLY RHEUMATOID ARTHRITIS].

    PubMed

    Rekalov, D

    2016-10-01

    The aim of the research was to study biomarkers of osteochondral lesions on early stages of rheumatoid arthritis (RA). The data showed the prognostic value of indicators of the erosive and destructive changes of joints in early and in the advanced stage of RA. Indicators that determine how directly, inflammatory process activity and markers associated with the speed and staging damage of articular surfaces is analyzed. That can adequately justify individualized clinical strategy in patients with early RA.

  12. Ovine Mesenchymal Stromal Cells: Morphologic, Phenotypic and Functional Characterization for Osteochondral Tissue Engineering

    PubMed Central

    Sanjurjo-Rodríguez, Clara; Castro-Viñuelas, Rocío; Hermida-Gómez, Tamara; Fernández-Vázquez, Tania; Fuentes-Boquete, Isaac Manuel; de Toro-Santos, Francisco Javier; Blanco-García, Francisco Javier

    2017-01-01

    Introduction Knowledge of ovine mesenchymal stromal cells (oMSCs) is currently expanding. Tissue engineering combining scaffolding with oMSCs provides promising therapies for the treatment of osteochondral diseases. Purpose The aim was to isolate and characterize oMSCs from bone marrow aspirates (oBMSCs) and to assess their usefulness for osteochondral repair using β-tricalcium phosphate (bTCP) and type I collagen (Col I) scaffolds. Methods Cells isolated from ovine bone marrow were characterized morphologically, phenotypically, and functionally. oBMSCs were cultured with osteogenic medium on bTCP and Col I scaffolds. The resulting constructs were evaluated by histology, immunohistochemistry and electron microscopy studies. Furthermore, oBMSCs were cultured on Col I scaffolds to develop an in vitro cartilage repair model that was assessed using a modified International Cartilage Research Society (ICRS) II scale. Results oBMSCs presented morphology, surface marker pattern and multipotent capacities similar to those of human BMSCs. oBMSCs seeded on Col I gave rise to osteogenic neotissue. Assessment by the modified ICRS II scale revealed that fibrocartilage/hyaline cartilage was obtained in the in vitro repair model. Conclusions The isolated ovine cells were demonstrated to be oBMSCs. oBMSCs cultured on Col I sponges successfully synthesized osteochondral tissue. The data suggest that oBMSCs have potential for use in preclinical models prior to human clinical studies. PMID:28141815

  13. Mechanical loading regulates human MSC differentiation in a multi-layer hydrogel for osteochondral tissue engineering.

    PubMed

    Steinmetz, Neven J; Aisenbrey, Elizabeth A; Westbrook, Kristofer K; Qi, H Jerry; Bryant, Stephanie J

    2015-07-01

    A bioinspired multi-layer hydrogel was developed for the encapsulation of human mesenchymal stem cells (hMSCs) as a platform for osteochondral tissue engineering. The spatial presentation of biochemical cues, via incorporation of extracellular matrix analogs, and mechanical cues, via both hydrogel crosslink density and externally applied mechanical loads, were characterized in each layer. A simple sequential photopolymerization method was employed to form stable poly(ethylene glycol)-based hydrogels with a soft cartilage-like layer of chondroitin sulfate and low RGD concentrations, a stiff bone-like layer with high RGD concentrations, and an intermediate interfacial layer. Under a compressive load, the variation in hydrogel stiffness within each layer produced high strains in the soft cartilage-like layer, low strains in the stiff bone-like layer, and moderate strains in the interfacial layer. When hMSC-laden hydrogels were cultured statically in osteochondral differentiation media, the local biochemical and matrix stiffness cues were not sufficient to spatially guide hMSC differentiation after 21 days. However dynamic mechanical stimulation led to differentially high expression of collagens with collagen II in the cartilage-like layer, collagen X in the interfacial layer and collagen I in the bone-like layer and mineral deposits localized to the bone layer. Overall, these findings point to external mechanical stimulation as a potent regulator of hMSC differentiation toward osteochondral cellular phenotypes. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  14. Computer tomographic evaluation of talar edge configuration for osteochondral graft transplantation.

    PubMed

    Wiewiorski, Martin; Hoechel, Sebastian; Wishart, Katarina; Leumann, André; Müller-Gerbl, Magdalena; Valderrabano, Victor; Nowakowski, Andrej Maria

    2012-09-01

    To successfully surgically reconstruct osteochondral lesions of the talus, the exact three-dimensional (3D) configuration of the upper articular surface of the talus has to be respected. We assessed the talar geometry by measuring the coronal and sagittal talar edge radius and the frontal talar profile in multiplanar reconstructions of computer tomographic (CT) studies of 79 patients (83 feet) with a healthy ankle joint. An image visualization software designated for coordinate measurement was used to perform the measurement. In the coronal plane, the mean lateral talar edge radius was 4.0 mm and the medial 4.5 mm. In the sagittal planes the mean lateral talar edge radius was 20.3 mm, the radius of the sulcus 20.7 mm and the medial talar edge radius 20.4 mm. The talus showed a concave shape in coronal cuts. These results show a significant difference between medial and lateral talar edge configuration in coronal planes. The measurements of the lateral and medial sagittal radius and the mid-sagittal radius in the sulcus tali show no statistically significant difference. The depth of the talar sulcus shows no correlation to age or sex. Different sizes of custom-made tissue-engineered grafts according to the location of the osteochondral lesion at the talus are needed for exact surgical reconstruction of the anatomy. Osteochondral lesions are three dimensional; therefore, a 3D preoperative planning tool by CT scan or MRI is mandatory. Copyright © 2012 Wiley Periodicals, Inc.

  15. Measurement of T1 relaxation time of osteochondral specimens using VFA-SWIFT

    PubMed Central

    Nissi, M. J.; Lehto, L. J.; Corum, C.A.; Idiyatullin, D.; Ellermann, J. M.; Gröhn, O. H. J.; Nieminen, M. T.

    2015-01-01

    Purpose To evaluate the feasibility of SWIFT with variable flip angle (VFA) for measurement of T1 relaxation time in Gd-agarose-phantoms and osteochondral specimens, including regions of very short T2*, and compare with T1 measured using standard methods. Methods T1s of agarose phantoms with variable concentration of Gd-DTPA2− and nine pairs of native and trypsin-treated bovine cartilage-bone specimens were measured. For specimens, VFA-SWIFT, inversion recovery (IR) fast spin echo (FSE) and saturation recovery FSE were used. For phantoms, additionally spectroscopic IR was used. Differences and agreement between the methods were assessed using non-parametric Wilcoxon and Kruskal-Wallis tests and intra-class correlation. Results The different T1 mapping methods agreed well in the phantoms. VFA-SWIFT allowed reliable measurement of T1 in the osteochondral specimens, including regions where FSE-based methods failed. The T1s measured by VFA-SWIFT were shifted towards shorter values in specimens. However, the measurements correlated significantly (highest correlation VFA-SWIFT vs. FSE was r=0.966). SNR efficiency was generally highest for SWIFT, especially in the subchondral bone. Conclusion Feasibility of measuring T1 relaxation time using VFA-SWIFT in osteochondral specimens and phantoms was demonstrated. A shift towards shorter T1s was observed for VFA-SWIFT in specimens, reflecting the higher sensitivity of SWIFT to short T2* spins. PMID:25111731

  16. The effect of devitalized trabecular bone on the formation of osteochondral tissue-engineered constructs

    PubMed Central

    Lima, Eric G.; Chao, Pen-hsiu Grace; Ateshian, Gerard A.; Bal, B. Sonny; Cook, James L.; Vunjak-Novakovic, Gordana; Hung, Clark T.

    2008-01-01

    In the current study, evidence is presented demonstrating that devitalized trabecular bone has an inhibitory effect on in vitro chondral tissue development when used as a base material for the tissue-engineering of osteochondral constructs for cartilage repair. Chondrocyte-seeded agarose hydrogel constructs were cultured alone or attached to an underlying bony base in a chemically defined medium formulation that has been shown to yield engineered cartilaginous tissue with native Young's modulus (EY) and glycosaminoglycan (GAG) content. By day 42 in culture the incorporation of a bony base significantly reduced these properties (EY = 87 ± 12 kPa, GAG = 1.9 ± 0.8%ww) compared to the gel-alone group (EY = 642 ± 97 kPa, GAG = 4.6 ± 1.4%ww). Similarly, the mechanical and biochemical properties of chondrocyte-seeded agarose constructs were inhibited when co-cultured adjacent to bone (unattached), suggesting that soluble factors rather than direct cell–bone interactions mediate the chondro-inhibitory bone effects. Altering the method of bone preparation, including demineralization, or the timing of bone introduction in co-culture did not ameliorate the effects. In contrast, osteochondral constructs with native cartilage properties (EY = 730 ± 65 kPa, GAG = 5.2 ± 0.9%ww) were achieved when a porous tantalum metal base material was adopted instead of bone. This work suggests that devitalized bone may not be a suitable substrate for long-term cultivation of osteochondral grafts. PMID:18718655

  17. A novel, visible light-induced, rapidly cross-linkable gelatin scaffold for osteochondral tissue engineering

    PubMed Central

    Mazaki, Tetsuro; Shiozaki, Yasuyuki; Yamane, Kentaro; Yoshida, Aki; Nakamura, Mariko; Yoshida, Yasuhiro; Zhou, Di; Kitajima, Takashi; Tanaka, Masato; Ito, Yoshihiro; Ozaki, Toshifumi; Matsukawa, Akihiro

    2014-01-01

    Osteochondral injuries remain difficult to repair. We developed a novel photo-cross-linkable furfurylamine-conjugated gelatin (gelatin-FA). Gelatin-FA was rapidly cross-linked by visible light with Rose Bengal, a light sensitizer, and was kept gelled for 3 weeks submerged in saline at 37°C. When bone marrow-derived stromal cells (BMSCs) were suspended in gelatin-FA with 0.05% Rose Bengal, approximately 87% of the cells were viable in the hydrogel at 24 h after photo-cross-linking, and the chondrogenic differentiation of BMSCs was maintained for up to 3 weeks. BMP4 fusion protein with a collagen binding domain (CBD) was retained in the hydrogels at higher levels than unmodified BMP4. Gelatin-FA was subsequently employed as a scaffold for BMSCs and CBD-BMP4 in a rabbit osteochondral defect model. In both cases, the defect was repaired with articular cartilage-like tissue and regenerated subchondral bone. This novel, photo-cross-linkable gelatin appears to be a promising scaffold for the treatment of osteochondral injury. PMID:24662725

  18. A review of terminology for equine juvenile osteochondral conditions (JOCC) based on anatomical and functional considerations.

    PubMed

    Denoix, J-M; Jeffcott, L B; McIlwraith, C W; van Weeren, P R

    2013-07-01

    This manuscript describes a new classification of the various joint-related lesions that can be seen in the young, growing horse based on their anatomical and functional aetiopathogenesis. Juvenile osteochondral conditions (JOCC) is a term that brings together specific disorders according to their location in the joint and their biomechanical origin. When a biomechanical insult affects the process of endochondral ossification different types of osteochondrosis (OC) lesions may occur, including osteochondral fragmentation of the articular surface or of the periarticular margins, or the formation of juvenile subchondral bone cysts. In severe cases, osteochondral collapse of the articular surface or the epiphysis or even an entire small bone may occur. Tension on ligament attachments may cause avulsion fractures of epiphyseal (or metaphyseal) ossifying bone, which are classified as JOCC, but do not result from a disturbance of the process of endochondral ossification and are not therefore classified as a form of OC. The same applies to 'physitis' which can result from damage to the physeal growth plate.

  19. Biocompatibility of biomimetic multilayered alginate-chitosan/β-TCP scaffold for osteochondral tissue.

    PubMed

    Algul, Derya; Sipahi, Hande; Aydin, Ahmet; Kelleci, Feyza; Ozdatli, Sukran; Yener, Fatma Gulgun

    2015-08-01

    Biomimetic three-layered monolithic scaffold (TLS) intended for treatment of osteochondral defects was fabricated by using freeze drying method. The multilayered material was prepared with chitosan (C) and alginate (A) polyelectrolyte complex (CA/PEC) as a cartilaginous layer, a combination of CA/PEC (60 wt%) and β-tricalcium phosphate (β-TCP) (40 wt%) as an intermediate layer and a combination of CA/PEC (30 wt%) and β-TCP (70 wt%) as a subchondral layer in order to mimic the inherent gradient structure of healthy osteochondral tissue. Characterization of the scaffolds was performed using Fourier transform infrared (FT-IR) spectroscopy analysis, swelling and scanning electron microscopy (SEM) tests. In vitro cytotoxicity assay with L929 cells and EpiDerm skin irritation test (SIT) using the EpiDerm reconstructed human epidermal (RHE) model were performed to analyze biocompatibility of the scaffolds. Characterization results showed that there were strong ionic interactions among chitosan, alginate and β-TCP and the layers showed interconnected porous structure with different swelling ratios. The relative cell viability and SIT results were greater than 70% indicating that the scaffolds are considered nontoxic according to the International Organization for Standardization (ISO) standard. All results taken together, biomimetic TLS can be considered to be suitable for osteochondral applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Spatial Engineering of Osteochondral Tissue Constructs Through Microfluidically Directed Differentiation of Mesenchymal Stem Cells.

    PubMed

    Goldman, Stephen M; Barabino, Gilda A

    2016-01-01

    The development of tissue engineered osteochondral units has been slowed by a number of technical hurdles associated with recapitulating their heterogeneous nature ex vivo. Subsequently, numerous approaches with respect to cell sourcing, scaffolding composition, and culture media formulation have been pursued, which have led to high variability in outcomes and ultimately the lack of a consensus bioprocessing strategy. As such, the objective of this study was to standardize the design process by focusing on differentially supporting formation of cartilaginous and bony matrix by a single cell source in a spatially controlled manner within a single material system. A cell-polymer solution of bovine mesenchymal stem cells and agarose was cast against micromolds of a serpentine network and stacked to produce tissue constructs containing two independent microfluidic networks. Constructs were fluidically connected to two controlled flow loops and supplied with independently tuned differentiation parameters for chondrogenic and osteogenic induction, respectively. Constructs receiving inductive media showed differential gene expression of both chondrogenic and osteogenic markers in opposite directions along the thickness of the construct that was recapitulated at the protein level with respect to collagens I, II, and X. A control group receiving noninductive media showed homogeneous expression of these biomarkers measured in lower concentrations at both the mRNA and protein level. This work represents an important step in the rational design of engineered osteochondral units through establishment of an enabling technology for further optimization of scaffolding formulations and bioprocessing conditions toward the production of commercially viable osteochondral tissue products.

  1. Changes in the osteochondral unit during osteoarthritis: structure, function and cartilage-bone crosstalk.

    PubMed

    Goldring, Steven R; Goldring, Mary B

    2016-11-01

    In diarthrodial joints, the articular cartilage, calcified cartilage, and subchondral cortical and trabecular bone form a biocomposite - referred to as the osteochondral unit - that is uniquely adapted to the transfer of load. During the evolution of the osteoarthritic process the compositions, functional properties, and structures of these tissues undergo marked alterations. Although pathological processes might selectively target a single joint tissue, ultimately all of the components of the osteochondral unit will be affected because of their intimate association, and thus the biological and physical crosstalk among them is of great importance. The development of targeted therapies against the osteoarthritic processes in cartilage or bone will, therefore, require an understanding of the state of these joint tissues at the time of the intervention. Importantly, these interventions will not be successful unless they are applied at the early stages of disease before considerable structural and functional alterations occur in the osteochondral unit. This Review describes the changes that occur in bone and cartilage during the osteoarthritic process, and highlights strategies for how this knowledge could be applied to develop new therapeutic interventions for osteoarthritis.

  2. Arthroscopic retrograde osteochondral autologous transplantation to chondral lesion in femoral head.

    PubMed

    Cetinkaya, Sarper; Toker, Berkin; Taser, Omer

    2014-06-01

    This report describes the treatment of 2 cases of full-thickness cartilage defect of the femoral head. The authors performed osteochondral autologous transplantation with a different technique that has not been reported to date. One patient was 37 years old, and the other was 42 years old. Both presented with hip pain. In both patients, radiograph and magnetic resonance imaging scan showed a focal chondral defect on the weight-bearing area of the femoral head and acetabular impingement. A retrograde osteochondral autologous transplantation technique combined with hip arthroscopy and arthroscopic impingement treatment was performed. After a 2-month recovery period, the symptoms were resolved. In the first year of follow-up, Harris Hip scores improved significantly (case 1, 56.6 to 87.6; case 2, 58.6 to 90). The technique described yielded good short- and midterm clinical and radiologic outcomes. To the authors' knowledge, this report is the first to describe a retrograde osteochondral transplantation technique performed with hip arthroscopy in the femoral head.

  3. Cochlear Implants.

    ERIC Educational Resources Information Center

    Clark, Catherine; Scott, Larry

    This brochure explains what a cochlear implant is, lists the types of individuals with deafness who may be helped by a cochlear implant, describes the process of evaluating people for cochlear implants, discusses the surgical process for implanting the aid, traces the path of sound through the cochlear implant to the brain, notes the costs of…

  4. Cochlear Implants.

    ERIC Educational Resources Information Center

    Clark, Catherine; Scott, Larry

    This brochure explains what a cochlear implant is, lists the types of individuals with deafness who may be helped by a cochlear implant, describes the process of evaluating people for cochlear implants, discusses the surgical process for implanting the aid, traces the path of sound through the cochlear implant to the brain, notes the costs of…

  5. Fabrication and development of artificial osteochondral constructs based on cancellous bone/hydrogel hybrid scaffold.

    PubMed

    Song, Kedong; Li, Liying; Yan, Xinyu; Zhang, Yu; Li, Ruipeng; Wang, Yiwei; Wang, Ling; Wang, Hong; Liu, Tianqing

    2016-06-01

    Using tissue engineering techniques, an artificial osteochondral construct was successfully fabricated to treat large osteochondral defects. In this study, porcine cancellous bones and chitosan/gelatin hydrogel scaffolds were used as substitutes to mimic bone and cartilage, respectively. The porosity and distribution of pore size in porcine bone was measured and the degradation ratio and swelling ratio for chitosan/gelatin hydrogel scaffolds was also determined in vitro. Surface morphology was analyzed with the scanning electron microscope (SEM). The physicochemical properties and the composition were tested by using an infrared instrument. A double layer composite scaffold was constructed via seeding adipose-derived stem cells (ADSCs) induced to chondrocytes and osteoblasts, followed by inoculation in cancellous bones and hydrogel scaffolds. Cell proliferation was assessed through Dead/Live staining and cellular activity was analyzed with IpWin5 software. Cell growth, adhesion and formation of extracellular matrix in composite scaffolds blank cancellous bones or hydrogel scaffolds were also analyzed. SEM analysis revealed a super porous internal structure of cancellous bone scaffolds and pore size was measured at an average of 410 ± 59 μm while porosity was recorded at 70.6 ± 1.7 %. In the hydrogel scaffold, the average pore size was measured at 117 ± 21 μm and the porosity and swelling rate were recorded at 83.4 ± 0.8 % and 362.0 ± 2.4 %, respectively. Furthermore, the remaining hydrogel weighed 80.76 ± 1.6 % of the original dry weight after hydration in PBS for 6 weeks. In summary, the cancellous bone and hydrogel composite scaffold is a promising biomaterial which shows an essential physical performance and strength with excellent osteochondral tissue interaction in situ. ADSCs are a suitable cell source for osteochondral composite reconstruction. Moreover, the bi-layered scaffold significantly enhanced cell proliferation compared to the cells seeded on

  6. Novel β-TCP/PVA bilayered hydrogels with considerable physical and bio-functional properties for osteochondral repair.

    PubMed

    Yao, Hang; Kang, Junpei; Li, Weichang; Liu, Jian; Xie, Renjian; Wang, Yingjun; Liu, Sa; Wang, Dong An; Ren, Li

    2017-08-09

    Cartilage repairing graft had been widely studied and the osteochondral replacement hydrogels were proved to be an excellent method in research and clinical. However, it was difficult to solve three main issues in osteochondral replacement preparation at one time: surface lubrication, overall mechanical support and good simulations of cell regeneration. A novel integrated bilayered hydrogel osteochondral replacement was constructed by blending polyvinyl alcohol (PVA) and β-tricalcium phosphate (β-TCP) in this study. Separated Nano-ball milling with ultrasound dispersion prepared β-TCP showed suitable properties of tiny particle size, high purity and ideal distribution, which made the novel integrated hydrogel acquired improved mechanical properties, cartilage-like lubrication effect and high biocompatibility including cytocompatibility and osteogenesis. The reinforcement of β-TCP and integrated molding technology made the hydrogel with excellent component compatibility and with good bonding exist between the two layers, which promoted the compression modulus and tensile modulus for up to 3 times strengthen by the mechanical test. The surface lubrication properties of the novel osteochondral hydrogel were similar to the natural cartilage by friction coefficient characterization. The two layer of novel integrated graft provided a considerable bio-function by co-cultured with chondrocytes and synovium mesenchymal stem cells: chondrocytes promoted adherence achieved by upper density layer and better osteogenesis performed by porous down layer. The design of bilayered β-TCP/PVA osteochondral hydrogel would be hopeful in articular cartilage repair. . © 2017 IOP Publishing Ltd.

  7. Penile Implants

    MedlinePlus

    Penile Implants Overview By Mayo Clinic Staff Penile implants are devices placed inside the penis to allow men with erectile dysfunction (ED) to get an erection. Penile implants are typically recommended after other treatments for ED ...

  8. Dental Implants.

    PubMed

    Griggs, Jason A

    2017-10-01

    Systematic reviews of literature over the period between 2008 and 2017 are discussed regarding clinical evidence for the factors affecting survival and failure of dental implants. The factors addressed include publication bias, tooth location, insertion torque, collar design, implant-abutment connection design, implant length, implant width, bone augmentation, platform switching, surface roughness, implant coatings, and the use of ceramic materials in the implant body and abutment. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Chances to Have A Boy after Gender Selection by Pre-Implantation Genetic Screening Are Reduced in Couples with only Girls and without A Boy Sired by The Male Partner

    PubMed Central

    Panahi, Soryya; Fahami, Fariba; Deemeh, Mohammad Reza; Tavalaee, Marziyeh; Gourabi, Hamid; Nasr-Esfahani, Mohammad Hossain

    2017-01-01

    Background Gender selection and family planning have their roots in human history. Despite great interest in these fields, very few scientific propositions exist which could explain why some family do not attain the desired sex. Therefore, the aim of this study was to evaluate whether sex of previous child or children could affect the outcomes of pre-implantation genetic screening (PGS). Materials and Methods This historical cohort study including 218 PGS cases referring to Isfahan Fertility and Infertility Center (IFIC). Couples were grouped as those who their male child passed away or her husbands’ has a son(s) from their previous marriage (n=70) and couples who just have daughter (n=148). Male normal blastocysts were transferred for both groups. The outcomes of PGS including pregnancy, implantation and abortion rates, along with possible confounding factors were compared between the two groups. Results Significant differences in pregnancy, implantation and abortion rates were observed between couples whose their male partner had/has one boy (n=70) compared to those who have just girl(s) (n=148) despite similar number and quality of male normal blastocyst transferred in the two groups. Confounding factors were also considered. Conclusion The Ybearing spermatozoa in male partners with no history of previous boy have lower ability to support a normal development to term, compared to male partners with previous history of boy requesting family balancing. PMID:28042415

  10. Autologous Chondrocyte Implantation: Past, Present, and Future.

    PubMed

    Welch, Tyler; Mandelbaum, Bert; Tom, Minas

    2016-06-01

    Focal cartilage defects of the knee are relatively common and may increase the risk of developing osteoarthritis. Autologous chondrocyte implantation (ACI) aims to restore the integrity of isolated cartilage lesions through the induction of hyaline-like cartilage formation. Although ACI has traditionally been used as a second-line treatment, recent evidence suggests that ACI should be considered as a first-line treatment option in certain patients. Recent controlled trials also suggest that there are improved clinical outcomes among those patients who undergo ACI over the mid-term and long-term compared with those treated with microfracture or osteochondral autograft/mosaicplasty, regardless of lesion size. Recent literature also indicates that arthroscopic, second-generation and third-generation techniques are associated with better outcomes and fewer complications than first-generation ACI. In summary, ACI is an effective tool for cartilage restoration that may be more efficacious and durable than other cartilage restoration techniques for appropriate candidates.

  11. Arthroscopic Particulated Juvenile Cartilage Allograft Transplantation for the Treatment of Osteochondral Lesions of the Talus

    PubMed Central

    Adams, Samuel B.; Demetracopoulos, Constantine A.; Parekh, Selene G.; Easley, Mark E.; Robbins, Justin

    2014-01-01

    Several options exist for the treatment of osteochondral lesions of the talus. Particulated juvenile cartilage allograft transplantation (PJCAT) has become a viable treatment modality for osteochondral lesions of the talus that are not amenable to microfracture or for which microfracture has failed. Arthroscopic placement of this type of graft obviates the need for osteotomy or plafondplasty and does not prevent additional procedures from being performed through an anterior approach. Special instrumentation and setup are not required to perform this procedure. Our arthroscopic technique for placement of particulated juvenile cartilage into osteochondral lesions of the talus is described. Case series and outcomes after arthroscopic ankle PJCAT are currently not reported within the literature; however, it is believed that the outcomes are at least similar to those of open ankle PJCAT. PMID:25264516

  12. Technical Report: Correlation Between the Repair of Cartilage and Subchondral Bone in an Osteochondral Defect Using Bilayered, Biodegradable Hydrogel Composites.

    PubMed

    Lu, Steven; Lam, Johnny; Trachtenberg, Jordan E; Lee, Esther J; Seyednejad, Hajar; van den Beucken, Jeroen J J P; Tabata, Yasuhiko; Kasper, F Kurtis; Scott, David W; Wong, Mark E; Jansen, John A; Mikos, Antonios G

    2015-12-01

    The present work investigated correlations between cartilage and subchondral bone repair, facilitated by a growth factor-delivering scaffold, in a rabbit osteochondral defect model. Histological scoring indices and microcomputed tomography morphological parameters were used to evaluate cartilage and bone repair, respectively, at 6 and 12 weeks. Correlation analysis revealed significant associations between specific cartilage indices and subchondral bone parameters that varied with location in the defect (cortical vs. trabecular region), time point (6 vs. 12 weeks), and experimental group (insulin-like growth factor-1 only, bone morphogenetic protein-2 only, or both growth factors). In particular, significant correlations consistently existed between cartilage surface regularity and bone quantity parameters. Overall, correlation analysis between cartilage and bone repair provided a fuller understanding of osteochondral repair and can help drive informed studies for future osteochondral regeneration strategies.

  13. High-throughput bone and cartilage micropellet manufacture, followed by assembly of micropellets into biphasic osteochondral tissue.

    PubMed

    Babur, Betul Kul; Futrega, Kathryn; Lott, William B; Klein, Travis Jacob; Cooper-White, Justin; Doran, Michael Robert

    2015-09-01

    Engineered biphasic osteochondral tissues may have utility in cartilage defect repair. As bone-marrow-derived mesenchymal stem/stromal cells (MSC) have the capacity to make both bone-like and cartilage-like tissues, they are an ideal cell population for use in the manufacture of osteochondral tissues. Effective differentiation of MSC to bone-like and cartilage-like tissues requires two unique medium formulations and this presents a challenge both in achieving initial MSC differentiation and in maintaining tissue stability when the unified osteochondral tissue is subsequently cultured in a single medium formulation. In this proof-of-principle study, we used an in-house fabricated microwell platform to manufacture thousands of micropellets formed from 166 MSC each. We then characterized the development of bone-like and cartilage-like tissue formation in the micropellets maintained for 8-14 days in sequential combinations of osteogenic or chondrogenic induction medium. When bone-like or cartilage-like micropellets were induced for only 8 days, they displayed significant phenotypic changes when the osteogenic or chondrogenic induction medium, respectively, was swapped. Based on these data, we developed an extended 14-day protocol for the pre-culture of bone-like and cartilage-like micropellets in their respective induction medium. Unified osteochondral tissues were formed by layering 12,000 osteogenic micropellets and 12,000 chondrogenic micropellets into a biphasic structure and then further culture in chondrogenic induction medium. The assembled tissue was cultured for a further 8 days and characterized via histology. The micropellets had amalgamated into a continuous structure with distinctive bone-like and cartilage-like regions. This proof-of-concept study demonstrates the feasibility of micropellet assembly for the formation of osteochondral-like tissues for possible use in osteochondral defect repair.

  14. The Use of Osteochondral Allograft Transplantation for Primary Treatment of Cartilage Lesions in the Knee

    PubMed Central

    Briggs, Dustin T.; Sadr, Kamran N.; Pulido, Pamela A.

    2015-01-01

    Objective: To assess the outcome of osteochondral allograft (OCA) transplantation as the primary treatment for cartilage injury in patients with no previous surgical treatment. Study Design: Case series. Patients were identified in our outcomes database. Patients undergoing primary OCA transplantation with no prior surgical treatment and a minimum of 2 years follow-up were selected. Pain and function were evaluated preoperatively and postoperatively. Patient satisfaction was assessed. Reoperations following OCA transplantation were captured. Failure was defined as revision OCA or conversion to arthroplasty. Results: Fifty-five patients (61 knees) were included in the analysis. The study consisted of 30 males and 25 females (mean age = 32.9 years; range = 15.7-67.8 years). The most common diagnoses for the OCA transplantation were osteochondritis dissecans (44.3%) and avascular necrosis (31.1%). Pain and function improved preoperatively to postoperatively on all outcome scales (P < 0.01). The majority of patients (86%) were “extremely satisfied” or “satisfied.” OCA survivorship was 89.5% at 5 years and 74.7% at 10 years. At latest follow-up (mean = 7.6 years; range = 1.9-22.6 years), OCA remained in situ in 50 knees (82%). Eighteen knees (29.5%) had further surgery; 11 OCA failures and 7 other surgical procedure(s). Of the failed knees (mean time to failure = 3.5 years; range = 0.5-13.7 years), 8 were converted to arthroplasty, 2 had OCA revisions, and 1 had a patellectomy. Conclusions: OCA transplantation is an acceptable primary treatment method for some chondral and osteochondral defects of the knee. Failure of previous treatment(s) is not a prerequisite for OCA transplantation. PMID:26425257

  15. The effects of low-dose radiotherapy on fresh osteochondral allografts: An experimental study in rabbits.

    PubMed

    Gönç, Uğur; Çetinkaya, Mehmet; Atabek, Mesut

    2016-10-01

    The aim of this study was to investigate the effects of low-dose fractionated radiotherapy on cartilage degeneration after distal femoral fresh massive osteochondral allograft transplantation. Twenty-four New Zealand White rabbits were divided into three groups of 8 rabbits each. All rabbits underwent distal femoral medial condyle fresh massive osteochondral allograft transplantation from California rabbits. The group 1 underwent transplantation without any preliminary process. The group 2 underwent fractionated local radiotherapy of 100 cGy for five days starting on the transplantation day. The group 3 included the rabbits to which the grafts transplanted after radiating in vitro by a single dose radiation of 1500 cGy. The hosts were sacrificed twelve weeks later. Anteroposterior and lateral radiographs were taken. Synovial tissue, cartilaginous tissue, and subchondral bone were assessed histopathologically. Nonunion was present in three cases of group 2 and one of group 3 in which cartilage degeneration was more severe. Synovial hypertrophy and pannus formation were more obvious in non-radiated rabbits. Hypocellularity and necrosis of the subchondral bone were rare in group 2. More cartilage tissue impairment was present in group 3 compared to group 1. In osteochondral massive allograft transplantations, the immune reaction of the host could be precluded with radiotherapy, and the side-effects can be prevented by low-dose fractionated regimen. The total dose of fractionated radiotherapy for an immune suppression should be adjusted not to damage the cartilage tissue, but to avoid articular degeneration in the long term. Copyright © 2016 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  16. Platelet-Rich Plasma May Improve Osteochondral Donor Site Healing in a Rabbit Model

    PubMed Central

    Smyth, Niall A.; Haleem, Amgad M.; Ross, Keir A.; Hannon, Charles P.; Murawski, Christopher D.; Do, Huong T.; Kennedy, John G.

    2016-01-01

    Purpose The purpose of this study was to assess the effect(s) of platelet-rich plasma (PRP) on osteochondral donor site healing in a rabbit model. Methods Osteochondral donor sites 3 mm in diameter and 5 mm in depth were created bilaterally on the femoral condyles of 12 New Zealand White rabbits. Knees were randomized such that one knee in each rabbit received an intra-articular injection of PRP and the other received saline (placebo). Rabbits were euthanized at 3, 6, and 12 weeks following surgery. Repair tissue was evaluated using the International Cartilage Repair Society (ICRS) macroscopic and histological scores. Results No complications occurred as a result of the interventions. There was no significant difference in macroscopic scores between the 2 groups (5.5 ± 3.8 vs. 3.8 ± 3.5; P = 0.13). Subjective macroscopic assessment determined greater tissue infill with fewer fissures and a more cartilage-like appearance in PRP-treated knees. Overall ICRS histological scores were better in the PRP group compared with the placebo (9.8 ± 2.0 vs. 7.8 ± 1.8; P = 0.04). Histological scores were also higher in the PRP group compared with the placebo group at each time point. Greater glycosaminoglycan and type II collagen content were noted in the repair tissue of the PRP group compared with the placebo group. Conclusion The results of this study indicate that PRP used as an intra-articular injection may improve osteochondral healing in a rabbit model. PMID:26958322

  17. Construction of tissue-engineered osteochondral composites and repair of large joint defects in rabbit.

    PubMed

    Deng, Tianzheng; Lv, Jing; Pang, Jianliang; Liu, Bing; Ke, Jie

    2014-07-01

    In this study, a novel three-dimensional (3D) heterogeneous/bilayered scaffold was constructed to repair large defects in rabbit joints. The scaffold includes two distinct but integrated layers corresponding to the cartilage and bone components. The upper layer consists of gelatin, chondroitin sulphate and sodium hyaluronate (GCH), and the lower layer consists of gelatin and ceramic bovine bone (GCBB). The two form a 3D bilayered scaffold (GCH-GCBB), which mimics the natural osteochondral matrix for use as a scaffold for osteochondral tissue engineering. The purpose of this study was to evaluate the efficacy of this novel scaffold, combined with chondrocytes and bone marrow stem cells (BMSCs) to repair large defects in rabbit joints. Thirty-six large defects in rabbit femoral condyles were created; 12 defects were treated with the same scaffold combined with cells (group A); another 12 defects were treated with cell-free scaffolds (group B); the others were untreated (group C). At 6 and 12 weeks, in group A hyaline-like cartilage formation could be observed by histological examination; the newly formed cartilage, which stained for type II collagen, was detected by RT-PCR at high-level expression. Most of the GCBB was replaced by bone, while little remained in the underlying cartilage. At 36 weeks, GCBB was completely resorbed and a tidemark was observed in some areas. In contrast, groups B and C showed no cartilage formation but a great amount of fibrous tissue, with only a little bone formation. In summary, this study demonstrated that a novel scaffold, comprising a top layer of GCH, having mechanical properties comparable to native cartilage, and a bottom layer composed of GCBB, could be used to repair large osteochondral defects in joints.

  18. Effect of Impaction Sequence on Osteochondral Graft Damage: The Role of Repeated and Varying Loads

    PubMed Central

    Kang, Richard W.; Friel, Nicole A.; Williams, James M.; Cole, Brian J.; Wimmer, Markus A.

    2013-01-01

    Background Osteochondral autografts and allografts require mechanical force for proper graft placement into the defect site; however, impaction compromises the tissue. This study aimed to determine the effect of impaction force and number of hits to seat the graft on cartilage integrity. Hypothesis Under constant impulse conditions, higher impaction load magnitudes are more detrimental to cell viability, matrix integrity and collagen network organization and will result in proteoglycan loss and nitric oxide release. Study Design Controlled laboratory study Methods Osteochondral explants, harvested from fresh bovine trochleas, were exposed to a series of consistent impact loads delivered by a pneumatically driven device. Each plug received the same overall impulse of 7 Ns, reflecting the mean of 23 clinically inserted plugs. Impaction loads of 37.5N, 75N, 150N, and 300N were matched with 74, 37, 21, and 11 hits respectively. Following impaction, the plugs were harvested and cartilage was analyzed for cell viability, histology by safranin-o and picosirius red, and release of sulfated glycosaminoglycans and nitric oxide. Data were compared with non-impacted control. Results Impacted plugs had significantly lower cell viability than non-impacted plugs. A dose response relationship in loss of cell viability with respect to load magnitude was seen immediately and after 4 days but lost after 8 days. Histologic analysis revealed intact cartilage surface in all samples (loaded or control), with loaded samples showing alterations in birefringence. While the sulfated GAG release was similar across varying impaction loads, release of nitric oxide increased with increasing impaction magnitudes and time. Conclusions Impaction loading parameters have a direct effect on the time course of the viability of the cartilage in the graft tissue. Clinical Relevance Optimal loading parameters for surgical impaction of osteochondral grafts are those with lower load magnitudes and a greater

  19. The therapeutic effect of low-level laser on repair of osteochondral defects in rabbit knee.

    PubMed

    Kamali, Fahimeh; Bayat, Mohammad; Torkaman, Giti; Ebrahimi, Esmaeel; Salavati, Mahyar

    2007-07-27

    Low level laser therapy (LLLT) has been shown to enhance collagen production and wound healing but its effect on cartilage repair from biomechanical point of view is not known yet. The aim of present study was to evaluate the biomechanical behaviour of repairing osteochondral defect in rabbits which received a pulsed low-level gallium-arsenide (Ga-As) laser irradiation. Osteochondral defects with 5mm diameter and 4mm in depth induced by drilling in right femoral patellar grooves of 41 adolescent male rabbits. They were divided into experimental and control groups. Experimental group received pulsed Ga-As (890nm) laser irradiation with energy density of 4.8J/cm(2). The rabbits in control group received placebo LLLT with shut-down equipment. The control defects were allowed to heal spontaneously. Each group were divided into three subgroups: A, B and C. Subgroups A, B and C were sacrificed on 4, 8, and 16 weeks after surgery. The knee joint were removed, and the defects were examined biomechanically by in situ-indentation method. The thickness, instantaneous and equilibrium indentation stiffness was measured during the test. Data were analysed using ANOVA and independent sample t-test. While no difference was observed in the repaired cartilage biomechanical properties among 4th, 8th, 16th weeks in study groups. The equilibrium indentation stiffness of experimental group was significantly higher in 8th week in comparison with control group. LLLT significantly enhances the stiffness of repairing tissue in the 8th week post injury in osteochondral defects in rabbits.

  20. Chondrocyte survival in osteochondral transplant cylinders depends on the harvesting technique.

    PubMed

    Hafke, Benedikt; Petri, Maximilian; Suero, Eduardo; Neunaber, Claudia; Kwisda, Sebastian; Krettek, Christian; Jagodzinski, Michael; Omar, Mohamed

    2016-07-01

    In autologous osteochondral transplantation, the edges of the harvested plug are particularly susceptible to mechanical or thermal damage to the chondrocytes. We hypothesised that the applied harvesting device has an impact on chondrocyte vitality. Both knees of five blackhead sheep (ten knees) underwent open osteochondral plug harvesting with three different circular harvesting devices (osteoarticular transfer system harvester [OATS; diameter 8 mm; Arthrex, Munich, Germany], diamond cutter [DC; diameter 8.35 mm; Karl Storz, Tuttlingen, Germany] and hollow reamer with cutting crown [HRCC; diameter 7 mm; Dannoritzer, Tuttlingen, Germany]) from distinctly assigned anatomical sites of the knee joint. The rotary cutters (DC and HRCC) were either used with (+) or without cooling (-). Surgical cuts of the cartilage with a scalpel blade were chosen as control method. After cryotomy cutting, chondrocyte vitality was assessed using fluorescence microscopy and a Live/Dead assay. There were distinct patterns of chondrocyte vitality, with reproducible accumulations of dead chondrocytes along the harvesting edge. No statistical difference in chondrocyte survivorship was seen between the OATS technique and the control method, or between the HRCC+ technique and the control method (P > 0.05). The DC+, HRCC- and DC- techniques yielded significantly lower chondrocyte survival rates compared with the control method (P < 0.05). Chondrocyte survival in osteochondral cylinders depends on the applied harvesting technique. The use of rotary cutters without cooling yielded worst results, while the traditional OATS punch and rotary cutters with cooling achieved comparable rates of chondrocyte vitality.

  1. Return to running following knee osteochondral repair using an anti-gravity treadmill: A case report.

    PubMed

    Hambly, Karen; Poomsalood, Somruthai; Mundy, Emma

    2017-07-01

    The purpose of this study was to assess the impact of an anti-gravity treadmill return to running programme on self-efficacy and subjective knee function following knee osteochondral surgery. A 39-year-old otherwise healthy female endurance runner with a left knee femoral cartilage grade 3-4 defect 3 cm(2). The patient underwent single step arthroscopic microfracture with Bone Marrow Aspirate Concentrate. An AlterG(®) anti-gravity treadmill was used to manipulate loading during a graduated phased return to running over 8 weeks. Self-efficacy was evaluated using the Self-Efficacy for Rehabilitation outcomes scale (SER) and the Knee Self-Efficacy Scale (K-SES). Subjective knee function was evaluated using the Knee injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee Subjective Knee Form (IKDC). The programme resulted in improvements in SER (57%), K-SES present (89%) and K-SES future (65%) self-efficacy domains. The IKDC score demonstrated a clinically important improvement with an increase from 62.1 in week 1-86.2 in week 8 (39%). Only the KOOS Sport/Rec subscale showed a clinically important improvement from week 1 to week 8. The programme resulted in improved knee and rehabilitation self-efficacy and subjective knee function following osteochondral repair of the knee. This case report illustrates the importance of considering self-efficacy in rehabilitation after knee osteochondral surgery and highlights the potential role for anti-gravity treadmills in enhancing self-efficacy and subjective knee function in preparation for a return to sport. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  2. Anatomical Glenoid Reconstruction Using Fresh Osteochondral Distal Tibia Allograft After Failed Latarjet Procedure.

    PubMed

    Sanchez, Anthony; Ferrari, Marcio B; Akamefula, Ramesses A; Frank, Rachel M; Sanchez, George; Provencher, Matthew T

    2017-04-01

    In the treatment of recurrent anterior glenohumeral instability, the Latarjet procedure has been shown to fail. This results in a need for viable revisional procedures for patients who present with this challenging pathology. We report our preferred technique for anatomical glenoid reconstruction using a fresh osteochondral distal tibia allograft after a failed Latarjet procedure. This bony augmentation technique employs a readily available dense, weight-bearing osseous tissue source that has excellent conformity, as well as the added benefit of a cartilaginous surface to correct chondral deficiencies. Given its effectiveness in the Latarjet revision setting and low complication rate, the distal tibia allograft is a reasonable treatment option.

  3. Aspects of Magnetic Resonance in the surgical treatment of osteochondral lesions of the knee.

    PubMed

    Macarini, Luca; Murrone, Mario; Marini, Stefania; Moretti, Biagio; Patella, Vittorio

    2003-01-01

    To assess the magnetic resonance (MR) appearance of knee cartilage chondroplasty procedures and their evolution in order to evaluate the usefulness of the method in monitoring postoperative rehabilitation. Sixty-two patients treated with knee chondroplasty for high-grade cartilage injuries (Noyes' stages II and III) were examined with MR. Forty patients were treated with abrasion chondroplasty, fifteen with osteochondral graft in the injury site and seven with the matrix-induced autologous chondrocyte transplant technique. All patients were operated on by the same orthopaedic team and examined with the same MR protocol. The MR follow-up was performed six months and one year after surgery in the patients treated with abrasion chondroplasty and osteochondral graft, and one week, three months and one year after surgery in the patients treated with cartilage transplant. In the patients treated with abrasion chondroplasty we assessed the fibrocartilage repair and the subchondral bone features, in the patients treated with osteochondral graft we examined the cartilage, the subchondral bone and the graft borders, while in the patients treated with cartilage transplant we evaluated the features and the evolution of the transplant and the subchondral bone. Arthrosynovitis was assessed in all patients. In seven patients a cartilage repair biopsy was performed in arthroscopy. In all the patients MR imaging proved useful in monitoring the chondroplasty. In the patients treated with abrasion chondroplasty the cartilage repair appeared as a hypointense non-homogeneous irregular strip of tissue that replaced the articular surface. The subchondral bone was sclerotic with some geodes. In the later examination the repair was unchanged. In the patients treated with osteochondral graft the articular cartilage was similar to the adjacent hyaline cartilage, although more non-homogeneous. The subchondral bone was sclerotic and in three cases oedematous. In four cases the graft extended

  4. Treatment of isolated chondral and osteochondral defects in the knee by autologous matrix-induced chondrogenesis (AMIC).

    PubMed

    Kusano, Taro; Jakob, Roland P; Gautier, Emanuel; Magnussen, Robert A; Hoogewoud, Henri; Jacobi, Matthias

    2012-10-01

    The purpose of this study is to evaluate clinical and radiological outcomes of patients treated with autologous matrix-induced chondrogenesis (AMIC) for full-thickness chondral and osteochondral defects of the femoral condyles and patella. A retrospective evaluation of clinical and radiographic outcomes of patients treated with AMIC for chondral and osteochondral full-thickness cartilage defects of the knee was performed with a mean follow-up of 28.8 ± 1.5 months (range, 13-51 months). Significant improvements in clinical outcome scores (IKDC, Lysholm, Tegner, and VAS pain score) were noted. The largest improvements were seen in the osteochondral subgroup (mean age 25.9 years), whereas patients treated for chondral defects in the patellofemoral joint and on the femoral condyles improved less. Patients in all groups were generally satisfied with their results. MRI evaluation showed that tissue filling was present but generally not complete or homogenous. AMIC is a safe procedure and leads to clinical improvement of symptomatic full-thickness chondral and osteochondral defects and to regenerative defect filling. The value of AMIC relative to other cartilage repair procedures and to the natural course remains undefined. Case series, Level IV.

  5. Chondrolysis of the Ankle Joint following Ankle Arthroscopy and Microfracture of the Osteochondral Lesion of the Talar Dome

    PubMed Central

    Lui, Tun Hing

    2013-01-01

    Chondrolysis of the ankle is a very rare condition. We report a case of chondrolysis of the ankle following ankle arthroscopy and microfracture of the osteochondral lesion of the talar dome. The patient's symptoms were relieved after articulated distraction arthroplasty. PMID:24369518

  6. Focal Defects of the Knee Articular Surface: Evidence of a Regenerative Potential Pattern in Osteochondritis Dissecans and Degenerative Lesions

    PubMed Central

    Gabusi, Elena; Manferdini, Cristina; Paolella, Francesca; Gambari, Laura; Mariani, Erminia

    2017-01-01

    The surgical treatment of knee articular focal lesions may offer heterogeneous clinical results. Osteochondritis dissecans (OCD) lesions showed to heal better than degenerative lesions (DL) but the underlying biological reasons are unknown. We evaluated the basal histological and immunohistochemical characteristics of these lesions analyzing a series of osteochondral fragments from young patients with similar age but presenting different etiology. Osteochondral tissue samples were stained with Safranin O and graded using a histological score. Markers of mesenchymal progenitor cells (CD146), osteoclasts (tartrate-resistant acid phosphatase, TRAP), and vessels (CD34) were evaluated. Histological score showed a higher degeneration of both cartilage and bone compartments in OCD compared to DL fragments. Only CD146-positive cells were found at the same percentage in cartilage compartment of both DL and OCD patients. By contrast, in the bone compartment a significantly higher percentage of CD146, TRAP, and CD34 markers was found in OCD compared to DL patients. These data showed distinct histological characteristics of osteochondral focal lesions located in the same anatomical region but having a different etiology. The higher percentages of these markers in OCD than in DL, mainly associated with a high bone turnover, could help to explain the higher clinical healing potential of OCD patients. PMID:28770227

  7. The effect of interface microstructure on interfacial shear strength for osteochondral scaffolds based on biomimetic design and 3D printing.

    PubMed

    Zhang, Weijie; Lian, Qin; Li, Dichen; Wang, Kunzheng; Hao, Dingjun; Bian, Weiguo; Jin, Zhongmin

    2015-01-01

    Interface integration between chondral phase and osseous phase is crucial in engineered osteochondral scaffolds. However, the integration was poorly understood and commonly failed to meet the need of osteochondral scaffolds. In this paper, a biphasic polyethylene glycol (PEG)/β-tricalcium phosphate (β-TCP) scaffold with enhanced interfacial integration was developed. The chondral phase was a PEG hydrogel. The osseous phase was a β-TCP ceramic scaffold. The PEG hydrogel was directly cured on the ceramic interface layer by layer to fabricate osteochondral scaffolds by 3D printing technology. Meanwhile, a series of interface structure were designed with different interface pore area percentages (0/10/20/30/40/50/60%), and interfacial shear test was applied for interface structure optimization (n=6 samples/group). The interfacial shear strength of 30% pore area group was nearly three folds improved compared with that of 0% pore area percentage group, and more than fifty folds improved compared with that of traditional integration (5.91±0.59 kPa). In conclusion, the biomimetic PEG/β-TCP scaffolds with interface structure enhanced integration show promising potential application for osteochondral tissue engineering. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Advancements in Orthopedic Intervention: Retrograde Drilling and Bone Grafting of Osteochondral Lesions of the Knee Using Magnetic Resonance Imaging Guidance

    SciTech Connect

    Seebauer, Christian J.; Bail, Hermann J.; Rump, Jens C. Walter, Thula Teichgraeber, Ulf K. M.

    2010-12-15

    Computer-assisted surgery is currently a novel challenge for surgeons and interventional radiologists. Magnetic resonance imaging (MRI)-guided procedures are still evolving. In this experimental study, we describe and assess an innovative passive-navigation method for MRI-guided treatment of osteochondritis dissecans of the knee. A navigation principle using a passive-navigation device was evaluated in six cadaveric knee joint specimens for potential applicability in retrograde drilling and bone grafting of osteochondral lesions using MRI guidance. Feasibility and accuracy were evaluated in an open MRI scanner (1.0 T Philips Panorama HFO MRI System). Interactive MRI navigation allowed precise drilling and bone grafting of osteochondral lesions of the knee. All lesions were hit with an accuracy of 1.86 mm in the coronal plane and 1.4 mm the sagittal plane. Targeting of all lesions was possible with a single drilling. MRI allowed excellent assessment of correct positioning of the cancellous bone cylinder during bone grafting. The navigation device and anatomic structures could be clearly identified and distinguished throughout the entire drilling procedure. MRI-assisted navigation method using a passive navigation device is feasible for the treatment of osteochondral lesions of the knee under MRI guidance and allows precise and safe drilling without exposure to ionizing radiation. This method may be a viable alternative to other navigation principles, especially for pediatric and adolescent patients. This MRI-navigated method is also potentially applicable in many other MRI-guided interventions.

  9. Comparison of three novel biphasic scaffolds for one-stage treatment of osteochondral defects in a sheep model.

    PubMed

    Gervaso, F; Mangiavini, L; Di Giancamillo, A; Boschetti, F; Izzo, D; Zani, D D; Di Giancamillo, M; Tessaro, I; Domenicucci, M; Scalera, F; Domeneghini, C; Crovace, A M; Sannino, A; Peretti, G M

    2016-01-01

    In the last years, several tissue engineering techniques have been applied to develop different kinds of osteochondral substitutes to overcome the scarce reparative properties of this tissue. The aim of this study was to generate and compare three biphasic scaffolds in an osteochondral lesion in a large-animal model. A critical osteochondral defect was generated in the medial femoral condyle of 18 skeletally mature sheep. Three defects were left untreated, the remaining lesions were divided into three groups: 5 lesions were treated with a biphasic scaffold made of collagen type I and small cylinders of Magnesium Hydroxyapatite; 5 lesions were treated with a biphasic substituted formed by collagen type I and Wollastonite, 5 lesions were treated with a scaffold made of collagen type I and small cylinders of Wollastonite/Hydroxyapatite. Animals were sacrificed after 3 months and samples were analyzed by CT and MRI, macroscopic evaluation and histology. Our study demonstrated that one of these novel biphasic scaffolds possesses the potential for being applied for one-stage procedures for osteochondral defects.

  10. Three-dimensional osteogenic and chondrogenic systems to model osteochondral physiology and degenerative joint diseases.

    PubMed

    Alexander, Peter G; Gottardi, Riccardo; Lin, Hang; Lozito, Thomas P; Tuan, Rocky S

    2014-09-01

    Tissue engineered constructs have the potential to function as in vitro pre-clinical models of normal tissue function and disease pathogenesis for drug screening and toxicity assessment. Effective high throughput assays demand minimal systems with clearly defined performance parameters. These systems must accurately model the structure and function of the human organs and their physiological response to different stimuli. Musculoskeletal tissues present unique challenges in this respect, as they are load-bearing, matrix-rich tissues whose functionality is intimately connected to the extracellular matrix and its organization. Of particular clinical importance is the osteochondral junction, the target tissue affected in degenerative joint diseases, such as osteoarthritis (OA), which consists of hyaline articular cartilage in close interaction with subchondral bone. In this review, we present an overview of currently available in vitro three-dimensional systems for bone and cartilage tissue engineering that mimic native physiology, and the utility and limitations of these systems. Specifically, we address the need to combine bone, cartilage and other tissues to form an interactive microphysiological system (MPS) to fully capture the biological complexity and mechanical functions of the osteochondral junction of the articular joint. The potential applications of three-dimensional MPSs for musculoskeletal biology and medicine are highlighted.

  11. Osteochondral Defects of the Knee treated with Mosaicplasty. Results at Eight Years of Follow-Up

    PubMed Central

    Zicaro, Juan Pablo; Romoli, Agustin Molina; Revah, Mariano Agustin; Dere, Juan Jose; Yacuzzi, Carlos; Costa-Paz, Matias

    2017-01-01

    Objectives: There are several surgical options described for osteochondral defects of the knee depending on the size, location and condition of subchondral bone. The main indication for a mosaicplasty procedure is a less than 4 cm2 femoral condyle lesion. The purpose of this study was to analyze a series of patients treated with mosaicplasty with average eight years of follow-up. Methods: We retrospectively evaluated sixty-two patients with osteochondral defects of the knee who underwent a mosaicplasty between 2001 and 2014 with a minimum follow-up of 2 years. Patients were evaluated using the Lysholm score, International Knee Documentation Committee Score (IKDC) and Kellgren-Lawrence radiographic scale. Results: The mean Lysholm score was 80.1 and IKDC was 66.7. Forty-two patients had isolated mosaicplasty and 20 patients presented an associated surgical procedure (osteotomy, ACL reconstruction, meniscectomy). There were no significant differences between the Lysholm and IKDC scores in these two groups. Conclusion: We consider that mosaicplasty is a satisfactory procedure with good functional results in patients with focal articular cartilage lesions of the knee.

  12. Image-Guided Techniques Improve the Short-Term Outcome of Autologous Osteochondral Cartilage Repair Surgeries

    PubMed Central

    Devlin, Steven M.; Hurtig, Mark B.; Waldman, Stephen D.; Rudan, John F.; Bardana, Davide D.; Stewart, A. James

    2013-01-01

    Objective: Autologous osteochondral cartilage repair is a valuable reconstruction option for cartilage defects, but the accuracy to harvest and deliver osteochondral grafts remains problematic. We investigated whether image-guided methods (optically guided and template guided) can improve the outcome of these procedures. Design: Fifteen sheep were operated to create traumatic chondral injuries in each knee. After 4 months, the chondral defect in one knee was repaired using (a) conventional approach, (b) optically guided method, or (c) template-guided method. For both image-guided groups, harvest and delivery sites were preoperatively planned using custom-made software. During optically guided surgery, instrument position and orientation were tracked and superimposed onto the surgical plan. For the template-guided group, plastic templates were manufactured to allow an exact fit between template and the joint anatomy. Cylindrical holes within the template guided surgical tools according to the plan. Three months postsurgery, both knees were harvested and computed tomography scans were used to compare the reconstructed versus the native pre-injury joint surfaces. For each repaired defect, macroscopic (International Cartilage Repair Society [ICRS]) and histological repair (ICRS II) scores were assessed. Results: Three months after repair surgery, both image-guided surgical approaches resulted in significantly better histology scores compared with the conventional approach (improvement by 55%, P < 0.02). Interestingly, there were no significant differences found in cartilage surface reconstruction and macroscopic scores between the image-guided and the conventional surgeries. PMID:26069658

  13. Stem cell- and scaffold-based tissue engineering approaches to osteochondral regenerative medicine

    PubMed Central

    Sundelacruz, Sarah; Kaplan, David L.

    2009-01-01

    In osteochondral tissue engineering, cell recruitment, proliferation, differentiation, and patterning are critical for forming biologically and structurally viable constructs for repair of damaged or diseased tissue. However, since constructs prepared ex vivo lack the multitude of cues present in the in vivo microenvironment, cells often need to be supplied with external biological and physical stimuli to coax them towards targeted tissue functions. To determine which stimuli to present to cells, bioengineering strategies can benefit significantly from endogenous examples of skeletogenesis. As an example of developmental skeletogenesis, the developing limb bud serves as an excellent model system in which to study how an osteochondral structures form from undifferentiated precursor cells. Alongside skeletal formation during embryogenesis, bone also possesses innate regenerative capacity, displaying remarkable ability to heal after damage. Bone fracture healing shares many features with bone development, driving the hypothesis that the regenerative process generally recapitulates development. Similarities and differences between the two modes of bone formation may offer insight into the special requirements for healing damaged or diseased bone. Thus, endogenous fracture healing, as an example of regenerative skeletogenesis, may also inform bioengineering strategies. In this review, we summarize the key cellular events involving stem and progenitor cells in developmental and regenerative skeletogenesis, and discuss in parallel the corresponding cell- and scaffold-based strategies that tissue engineers employ to recapitulate these events in vitro. PMID:19508851

  14. Injectable and 3D Bioprinted Polysaccharide Hydrogels: From Cartilage to Osteochondral Tissue Engineering.

    PubMed

    Radhakrishnan, Janani; Subramanian, Anuradha; Krishnan, Uma Maheswari; Sethuraman, Swaminathan

    2017-01-09

    Biomechanical performance of functional cartilage is executed by the exclusive anisotropic composition and spatially varying intricate architecture in articulating ends of diarthrodial joint. Osteochondral tissue constituting the articulating ends comprise superfical soft cartilage over hard subchondral bone sandwiching interfacial soft-hard tissue. The shock-absorbent, lubricating property of cartilage and mechanical stability of subchondral bone regions are rendered by extended chemical structure of glycosaminoglycans and mineral deposition, respectively. Extracellular matrix glycosaminoglycans analogous polysaccharides are major class of hydrogels investigated for restoration of functional cartilage. Recently, injectable hydrogels have gained momentum as it offers patient compliance, tunable mechanical properties, cell deliverability, and facile administration at physiological condition with long-term functionality and hyaline cartilage construction. Interestingly, facile modifiable functional groups in carbohydrate polymers impart tailorability of desired physicochemical properties and versatile injectable chemistry for the development of highly potent biomimetic in situ forming scaffold. The scaffold design strategies have also evolved from single component to bi- or multilayered and graded constructs with osteogenic properties for deep subchondral regeneration. This review highlights the significance of polysaccharide structure-based functions in engineering cartilage tissue, injectable chemistries, strategies for combining analogous matrices with cells/stem cells and biomolecules and multicomponent approaches for osteochondral mimetic constructs. Further, the rheology and precise spatiotemporal positioning of cells in hydrogel bioink for rapid prototyping of complex three-dimensional anisotropic cartilage have also been discussed.

  15. Specific inductive potential of a novel nanocomposite biomimetic biomaterial for osteochondral tissue regeneration.

    PubMed

    Manferdini, C; Cavallo, C; Grigolo, B; Fiorini, M; Nicoletti, A; Gabusi, E; Zini, N; Pressato, D; Facchini, A; Lisignoli, G

    2016-05-01

    Osteochondral lesions require treatment to restore the biology and functionality of the joint. A novel nanostructured biomimetic gradient scaffold was developed to mimic the biochemical and biophysical properties of the different layers of native osteochondral structure. The present results show that the scaffold presents important physicochemical characteristics and can support the growth and differentiation of mesenchymal stromal cells (h-MSCs), which adhere and penetrate into the cartilaginous and bony layers. H-MSCs grown in chondrogenic or osteogenic medium decreased their proliferation during days 14-52 on both scaffold layers and in medium without inducing factors used as controls. Both chondrogenic and osteogenic differentiation of h-MSCs occurred from day 28 and were increased on day 52, but not in the control medium. Safranin O staining and collagen type II and proteoglycans immunostaining confirmed that chondrogenic differentiation was specifically induced only in the cartilaginous layer. Conversely, von Kossa staining, osteocalcin and osteopontin immunostaining confirmed that osteogenic differentiation occurred on both layers. This study shows the specific potential of each layer of the biomimetic scaffold to induce chondrogenic or osteogenic differentiation of h-MSCs. These processes depended mainly on the media used but not the biomaterial itself, suggesting that the local milieu is fundamental for guiding cell differentiation. Copyright © 2013 John Wiley & Sons, Ltd. Copyright © 2013 John Wiley & Sons, Ltd.

  16. Indentation of an osteochondral repair: sensitivity to experimental variables and boundary conditions.

    PubMed

    Smith, C L; Mansour, J M

    2000-11-01

    The sensitivity of the affects of indenter radius, defect depth, cartilage permeability and flow boundary conditions, on the indentation testing of a repairing osteochondral defect was investigated. Since the boundary condition on the flow across the cartilage repair-subchondral bone interface is not known, the effects of two different conditions were investigated: free-flow and no-flow. A poroelastic finite element model of an osteochondral defect at different stages of the repair process was developed using dimensions typical of the rabbit knee. Results showed when the radius of the indenter was much less than the thickness of the cartilage the sensitivity of the indentation displacement to flow boundary conditions decreased. Simulated indentation displacement was insensitive to bone regeneration up to 50% of the initial defect depth, which suggests that only the properties of the material in the upper-half of the defect are being evaluated. Small variations in permeability had little affect on the simulated indentation. In a fully repaired defect, the simulated indentation is independent of the boundary condition. However, while the defect is in the process of repair and the regenerated cartilage is deeper than the host, indentation is sensitive to the flow boundary condition. Based on these results, and feasible experimental conditions, we conclude that the boundary condition on the repair-subchondral bone interface must be known in all cases except when the defect approaches full repair, if accurate estimates of material properties are to be obtained from indentation.

  17. Repair of articular cartilage in rabbit osteochondral defects promoted by extracorporeal shock wave therapy

    NASA Astrophysics Data System (ADS)

    Chu, C.-H.; Yen, Y.-S.; Chen, P.-L.; Wen, C.-Y.

    2015-03-01

    This study investigated the stimulative effect of extracorporeal shock wave therapy (ESWT) on the articular cartilage regeneration in the rabbit osteochondral defect model for the first time. An osteochondral defect, 3 mm in diameter and 3 mm in depth, was drilled in the patellar groove at the distal end of each femur in 24 mature New Zealand rabbits. The right patellar defects received 500 impulses of shock waves of (at 14 kV) at 1 week after surgery and were designated as the experimental samples; the left patellar defects served as control. At 4, 8, and 12 weeks after ESWT, cartilage repair was evaluated macroscopically and histologically using a semiquantitative grading scale. The total scores of the macroscopic evaluation at 4, 8, and 12 weeks in the experimental group were superior to those in the control group (statistical significance level ). As to the total scores of the histologic evaluation, the experimental group showed a tendency toward a better recovery than the control group at 4 weeks (). At 8 and 12 weeks the differences between the experimental and control groups became mild and had no significance on statistical analysis. These findings suggested that regeneration of articular cartilage defects might be promoted by ESWT, especially at the early stage. The easy and safe ESWT is potentially viable for clinical application.

  18. Alterations of the subchondral bone in osteochondral repair--translational data and clinical evidence.

    PubMed

    Orth, P; Cucchiarini, M; Kohn, D; Madry, H

    2013-06-28

    Alterations of the subchondral bone are pathological features associated with spontaneous osteochondral repair following an acute injury and with articular cartilage repair procedures. The aim of this review is to discuss their incidence, extent and relevance, focusing on recent knowledge gained from both translational models and clinical studies of articular cartilage repair. Efforts to unravel the complexity of subchondral bone alterations have identified (1) the upward migration of the subchondral bone plate, (2) the formation of intralesional osteophytes, (3) the appearance of subchondral bone cysts, and (4) the impairment of the osseous microarchitecture as potential problems. Their incidence and extent varies among the different small and large animal models of cartilage repair, operative principles, and over time. When placed in the context of recent clinical investigations, these deteriorations of the subchondral bone likely are an additional, previously underestimated, factor that influences the long-term outcome of cartilage repair strategies. Understanding the role of the subchondral bone in both experimental and clinical articular cartilage repair thus holds great promise of being translated into further improved cell- or biomaterial-based techniques to preserve and restore the entire osteochondral unit.

  19. A Hydrogel-Mineral Composite Scaffold for Osteochondral Interface Tissue Engineering

    PubMed Central

    Khanarian, Nora T.; Jiang, Jie; Wan, Leo Q.; Mow, Van C.

    2012-01-01

    Osteoarthritis is the leading cause of physical disability among Americans, and tissue engineered cartilage grafts have emerged as a promising treatment option for this debilitating condition. Currently, the formation of a stable interface between the cartilage graft and subchondral bone remains a significant challenge. This study evaluates the potential of a hybrid scaffold of hydroxyapatite (HA) and alginate hydrogel for the regeneration of the osteochondral interface. Specifically, the effects of HA on the response of chondrocytes were determined, focusing on changes in matrix production and mineralization, as well as scaffold mechanical properties over time. Additionally, the optimal chondrocyte population for interface tissue engineering was evaluated. It was observed that the HA phase of the composite scaffold promoted the formation of a proteoglycan- and type II collagen–rich matrix when seeded with deep zone chondrocytes. More importantly, the elevated biosynthesis translated into significant increases in both compressive and shear moduli relative to the mineral-free control. Presence of HA also promoted chondrocyte hypertrophy and type X collagen deposition. These results demonstrate that the hydrogel–calcium phosphate composite supported the formation of a calcified cartilage-like matrix and is a promising scaffold design for osteochondral interface tissue engineering. PMID:21919797

  20. Novel Vanadium-Loaded Ordered Collagen Scaffold Promotes Osteochondral Differentiation of Bone Marrow Progenitor Cells

    PubMed Central

    Cortizo, Ana M.; Ruderman, Graciela; Mazzini, Flavia N.; Molinuevo, M. Silvina; Mogilner, Ines G.

    2016-01-01

    Bone and cartilage regeneration can be improved by designing a functionalized biomaterial that includes bioactive drugs in a biocompatible and biodegradable scaffold. Based on our previous studies, we designed a vanadium-loaded collagen scaffold for osteochondral tissue engineering. Collagen-vanadium loaded scaffolds were characterized by SEM, FTIR, and permeability studies. Rat bone marrow progenitor cells were plated on collagen or vanadium-loaded membranes to evaluate differences in cell attachment, growth and osteogenic or chondrocytic differentiation. The potential cytotoxicity of the scaffolds was assessed by the MTT assay and by evaluation of morphological changes in cultured RAW 264.7 macrophages. Our results show that loading of VOAsc did not alter the grooved ordered structure of the collagen membrane although it increased membrane permeability, suggesting a more open structure. The VOAsc was released to the media, suggesting diffusion-controlled drug release. Vanadium-loaded membranes proved to be a better substratum than C0 for all evaluated aspects of BMPC biocompatibility (adhesion, growth, and osteoblastic and chondrocytic differentiation). In addition, there was no detectable effect of collagen or vanadium-loaded scaffolds on macrophage viability or cytotoxicity. Based on these findings, we have developed a new ordered collagen scaffold loaded with VOAsc that shows potential for osteochondral tissue engineering. PMID:27293438

  1. Evaluation of cartilage, synovium and adipose tissue as cellular sources for osteochondral repair.

    PubMed

    Innes, J F; Gordon, C; Vaughan-Thomas, A; Rhodes, N P; Clegg, P D

    2013-09-01

    Osteochondral lesions are a major cause of pain and disability in several species including dogs, horses and human beings. The objective of this study was to assess three potential sources of canine cells for their osteochondral regenerative potential. Cartilage, synovium and adipose tissue cells were grown in pellet culture in chondrogenic or osteogenic media. Cartilage-derived pellets displayed the best chondrogenic differentiation as indicated by significantly higher COL2A1 and SOX9 mRNA expression, greater glycosaminoglycan content, and higher retention of Safranin-O stain compared to the synovium and adipose-derived cells. Following application of the osteogenic media, all three cell sources exhibited small areas of positive alizarin red staining. Poor intracellular alkaline phosphatase activity was found in all three cell types when stimulated although osteocalcin and RUNX2 expression were significantly increased. Cells isolated and cultured from canine articular cartilage retained their specific chondrocytic phenotype. Furthermore, canine adipocytes and synovial cells did not undergo chondrogenic differentiation and did not exhibit evidence of multipotency. Although osteogenic differentiation was initiated at a genomic level, phenotypic osteoblastic differentiation was not observed. The findings of this study suggest that cells isolated from canine adipose tissue and synovium are sub-optimal substitutes for chondrocytes when engineering articular cartilage in vitro.

  2. Joint laminate degradation assessed by reflected ultrasound from the cartilage surface and osteochondral junction

    NASA Astrophysics Data System (ADS)

    Brown, C. P.; Hughes, S. W.; Crawford, R. W.; Oloyede, A.

    2008-08-01

    The ability to quantify and qualify the progression of joint degeneration is becoming increasingly important in surgery. This paper examines the patterns of relative ultrasound reflection from normal, artificially and naturally degraded cartilage-on-bone, particularly investigating the potential of the ratio of reflection coefficients from the surface and osteochondral junction in distinguishing normal from osteoarthritic tissue. To this end, the reflection coefficients from the articular surface and osteochondral junction of normal cartilage-on-bone samples were calculated and compared to samples after the removal of proteoglycans, disruption of the collagen meshwork, delipidization of the articular surface and mechanical abrasion. Our results show that the large variation across normal and degraded joint samples negates the use of an isolated bone reflection measurement and to a lesser extent, an isolated surface reflection. The relative surface to bone reflections, calculated as a ratio of reflection coefficients, provided a more consistent and statistically significant (p < 0.001) method for distinguishing each type of degradation, especially osteoarthritic degradation, and due to the complementary relationship between surface and bone reflections was found to be an effective method for distinguishing degraded from normal tissue in the osteoarthritic joint, independent of the site of initiation of the osteoarthritic process.

  3. Dental Implants.

    PubMed

    Zohrabian, Vahe M; Sonick, Michael; Hwang, Debby; Abrahams, James J

    2015-10-01

    Dental implants restore function to near normal in partially or completely edentulous patients. A root-form implant is the most frequently used type of dental implant today. The basis for dental implants is osseointegration, in which osteoblasts grow and directly integrate with the surface of titanium posts surgically embedded into the jaw. Radiologic assessment is critical in the preoperative evaluation of the dental implant patient, as the exact height, width, and contour of the alveolar ridge must be determined. Moreover, the precise locations of the maxillary sinuses and mandibular canals, as well as their relationships to the site of implant surgery must be ascertained. As such, radiologists must be familiar with implant design and surgical placement, as well as augmentation procedures utilized in those patients with insufficient bone in the maxilla and mandible to support dental implants.

  4. Penile Implants

    MedlinePlus

    ... Three-piece inflatable implants use a fluid-filled reservoir implanted under the abdominal wall, a pump and ... an erection, you pump the fluid from the reservoir into the cylinders. Afterward, you release the valve ...

  5. Comparison of Clinical and Radiographic Outcomes Between Central and Lateral Lesions After Osteochondral Autograft Transplantation for Osteochondritis Dissecans of the Humeral Capitellum.

    PubMed

    Matsuura, Takeshi; Hashimoto, Yusuke; Nishino, Kazuya; Nishida, Yohei; Takahashi, Shinji; Shimada, Nagakazu

    2017-09-01

    Clinical studies have reported satisfactory results after osteochondral autograft transplantation (OAT) for central lesions of unstable osteochondritis dissecans (OCD) of the elbow. However, the outcomes after OAT for lateral lesions remain unclear. The clinical outcomes of OAT would be better for central lesions than for lateral lesions. Cohort study; Level of evidence, 3. The authors retrospectively evaluated 103 juvenile athletes (mean age, 13.2 years; range, 11-16 years) who underwent OAT for symptomatic OCD of the humeral capitellum from 2003 to 2014. Sixteen patients were excluded because they did not fit the inclusion criteria. The final cohort of 87 patients was divided by lesion type into central lesion (n = 43) and lateral lesion (n = 44) groups. When possible, a single large plug was created for grafting and trimmed to reconstruct the rounded joint surface. The clinical, radiographic, and magnetic resonance imaging outcomes were evaluated for each group at a mean follow-up of 43 months (range, 24-100 months). There were no significant differences in the age, sex, height, weight, duration of symptoms, follow-up time, preoperative range of motion, or Timmerman and Andrews score between the 2 groups. The preoperative osteoarthritic changes (0 of 43 for central vs 5 of 44 cases for lateral; P = .023), mean lesion size (12.2 ± 2.9 vs 18.2 ± 7.0 mm; P < .001), and graft number (1.6 vs 2.8; P < .001) were significantly greater in the lateral group versus the central group. The mean range of extension (2.3° ± 5.4° vs -3.2° ± 8.7°; P < .001) and Timmerman and Andrews score (194 vs 185; P = .006) at the final follow-up were significantly better for patients in the central group. More patients in the lateral group had postoperative radial head subluxation (0 of 43 vs 6 of 44; P = .012) and osteoarthritic changes (1 of 43 vs 9 of 44; P = .008). The mean MOCART score showed no significant differences between the groups (78.0 ± 15.7 vs 72.6 ± 20.9; P = .181

  6. Wireless power transfer to a cardiac implant

    NASA Astrophysics Data System (ADS)

    Kim, Sanghoek; Ho, John S.; Chen, Lisa Y.; Poon, Ada S. Y.

    2012-08-01

    We analyze wireless power transfer between a source and a weakly coupled implant on the heart. Numerical studies show that mid-field wireless powering achieves much higher power transfer efficiency than traditional inductively coupled systems. With proper system design, power sufficient to operate typical cardiac implants can be received by millimeter-sized coils.

  7. Post-traumatic malunion of the distal radial intra-articular fractures treated with autologous costal osteochondral grafts and bioabsorbable plates.

    PubMed

    Furukawa, Kayoko; Sakai, Akinori; Menuki, Kunitaka; Oshige, Toshihisa; Zenke, Yukichi; Nakamura, Toshitaka

    2014-03-01

    Intra-articular distal radial fractures with partial bone loss at the wrist were reconstructed using osteochondral grafts in 2 patients who were followed up for at least 18 months. Both patients experienced posttraumatic arthrosis of the wrist joint. The materials of the intra-articular fixation were bioabsorbable plates and screws. Reconstruction of a partially destroyed articular surface using a costal osteochondral graft is reliable and allows filling and resurfacing an articular cartilage void.

  8. Growth Factor Gradients via Microsphere Delivery in Biopolymer Scaffolds for Osteochondral Tissue Engineering

    PubMed Central

    Wang, Xiaoqin; Wenk, Esther; Zhang, Xiaohui; Meinel, Lorenz; Vunjak-Novakovic, Gordana; Kaplan, David L.

    2009-01-01

    Temporally and spatially controlled delivery of growth factors in polymeric scaffolds is crucial for engineering composite tissue structures, such as osteochondral constructs. In the present study, microsphere-mediated growth factor delivery in polymer scaffolds and its impact on osteochondral differentiation of human bone marrow-derived mesenchymal stem cells (hMSCs) was evaluated. Two growth factors, bone morphogenetic protein 2 (rhBMP-2) and insulin-like growth factor I (rhIGF-I), were incorporated as a single concentration gradient or reverse gradient combining two factors in the scaffolds. To assess the gradient making system and the delivery efficiency of polylactic-co-glycolic acid (PLGA) and silk fibroin microspheres, initially an alginate gel was fabricated into a cylinder shape with microspheres incorporated as gradients. Compared to PLGA microspheres, silk microspheres were more efficient in delivering rhBMP-2, probably due to sustained release of the growth factor, while less efficient in delivering rhIGF-I, likely due to loading efficiency. The growth factor gradients formed were shallow, inducing non-gradient trends in hMSC osteochondral differentiation. Aqueous-derived silk porous scaffolds were used to incorporate silk microspheres using the same gradient process. Both growth factors formed deep and linear concentration gradients in the scaffold, as shown by enzyme-linked immunosorbent assay (ELISA). After seeding with hMSCs and culturing for 5 weeks in a medium containing osteogenic and chondrogenic components, hMSCs exhibited osteogenic and chondrogenic differentiation along the concentration gradients of rhBMP-2 in the single gradient of rhBMP-2 and reverse gradient of rhBMP-2/rhIGF-I, but not the rhIGF-I gradient system, confirming that silk microspheres were more efficient in delivering rhBMP-2 than rhIGF-I for hMSCs osteochondrogenesis. This novel silk microsphere/scaffold system offers a new option for the delivery of multiple growth factors

  9. Operative Management of Osteochondritis Dissecans: Progression to Osteoarthritis and Arthroplasty in a Population Based Cohort

    PubMed Central

    Sanders, Thomas L.; Pareek, Ayoosh; Johnson, Nick R.; Mohan, Rohith; Carey, James L.; Stuart, Michael J.; Krych, Aaron John

    2017-01-01

    Objectives: Osteochondritis dissecans (OCD) is a disorder of subchondral bone that causes adverse effects on the overlying cartilage and commonly affects the knee. The purpose of this study is to (1) evaluate the rate of arthritis and knee arthroplasty in a population-based cohort of patients with OCD lesions treated operatively and (2) evaluate factors that may predispose patients to knee osteoarthritis and arthroplasty. Methods: 221 patients (mean age 26.1 ± 13.6 years) with OCD lesions treated operatively were identified between 1976 and 2014 and followed for a mean of 16.3 (±11.4) years from diagnosis. Information related to the diagnosis, laterality of lesion, details of treatment, and progression to arthritis was obtained from the medical record. Surgical treatment was classified as palliative (fragment excision) or restorative (lesion drilling, fragment fixation, osteochondral allograft or autograft). Factors predictive of arthritis and arthroplasty were examined. Results: In the palliative group, the cumulative incidence of arthritis was 12.0% at 5 years, 17.0% at 10 years, 26.0% at 15 years, 39.0% at 20 years, and 70% at 30 years. The cumulative incidence of arthroplasty was 2.0% at 5 years, 4.0% at 10 years, 4.0% at 15 years, 10.0% at 20 years, and 32.0% at 30 years. In the restorative group, the cumulative incidence of arthritis was 3.0% at 5 years, 7.0% at 10 years, 16.0% at 15 years, 25.0% at 20 years, and 51% at 30 years. The cumulative incidence of arthroplasty was 0.0% at 5 years, 0.0% at 10 years, 3.0% at 15 years, 6.0% at 20 years, and 11.0% at 30 years. BMI greater than 25 kg/m2 (HR 3.3, 95% CI: 1.6, 7.0), older age at diagnosis (HR 4.9, 95% CI: 1.8, 17.3) and fragment excision (HR 2.3, 95% CI: 1.2, 4.6) were predictive of arthritis. Conclusion: OCD patients treated with fragment excision have a high rate of arthritis and knee arthroplasty at long-term follow-up. In contrast, patients treated with fragment repair or osteochondral restoration

  10. Comparison of clinical outcomes between arthroscopic subchondral drilling and microfracture for osteochondral lesions of the talus.

    PubMed

    Choi, Jun-Ik; Lee, Keun-Bae

    2016-07-01

    The objectives of this study were to compare the clinical outcomes of the two common bone marrow stimulation techniques such as subchondral drilling and microfracture for symptomatic osteochondral lesions of the talus and to evaluate prognostic factors affecting the outcomes. Ninety patients (90 ankles) who underwent arthroscopic bone marrow stimulation for small- to mid-sized osteochondral lesions of the talus constituted the study cohort. The 90 ankles were divided into two groups: a drilling group (40 ankles) and a microfracture group (50 ankles). Each group was matched for age and gender, and both groups had characteristics similar to those obtained from pre-operative demographic data. The American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and the ankle activity score (AAS) were used to compare clinical outcomes, during a mean follow-up period of 43 months. The median AOFAS scores were 66.0 points (51-80) in drilling group and 66.5 points (45-81) in microfracture group pre-operatively, and these improved to 89.4 points (77-100) and 90.1 points (69-100) at the final follow-up, respectively. The median VAS scores improved at the final follow-up compared with the pre-operative condition. The median AAS for the drilling group improved from 4.5 (1-6) pre-operatively to 6.0 (1-8) at the final follow-up, while those for the microfracture group improved from 3.0 (2-8) to 6.0 (3-9). No significant differences were observed between the two groups in terms of the AOFAS scores, VAS, and AAS. The arthroscopic subchondral drilling and microfracture techniques that were used to stimulate bone marrow showed similar clinical outcomes. The results of this study suggest that both techniques are effective and reliable in treating small- to mid-sized osteochondral lesions of the talus, regardless of which of the two techniques is used. Level III, retrospective comparative study.

  11. Mapping of cartilage depth in the knee and elbow for use in osteochondral autograft procedures.

    PubMed

    Schub, David L; Frisch, Nicholas C; Bachmann, Keith R; Winalski, Carl; Saluan, Paul M

    2013-04-01

    Osteochondritis dissecans (OCD) of the elbow is a problematic condition that affects a fair number of young athletes. One treatment option is the use of osteochondral autografts, which are commonly taken from donor sites on the less weightbearing surfaces of the knee. To use magnetic resonance imaging (MRI) to assess the cartilage depths of sites in the knee and elbow that are commonly used as donor and recipient sites to optimize depth matching for osteochondral autograft procedures. Descriptive laboratory study. All knee and elbow MRI scans acquired from 3-T machines in patients aged 16 to 25 years within a single hospital system were reviewed. Studies were excluded if there had been previous surgery on the joint or if there were significant chondral defects in the areas to be measured. All cartilage depth measurements were independently performed by 3 different physicians to the nearest 0.01 mm. At the elbow, 6 locations on the capitellum and 2 on the trochlea were chosen. At the knee, 4 locations along the anterior-lateral femoral condyle, 5 surrounding the intercondylar notch, and 1 on both the medial- and lateral-posterior femoral condyles were chosen. There were 111 knee MRI (74 male, 37 female) and 94 elbow MRI (85 male, 9 female) scans that met all inclusion criteria. The average cartilage depths from each investigator were then averaged to provide an overall mean depth at each location. All average cartilage depths within the knee were thicker than those in the elbow, where the averaged mean thickness of all the 8 measured sites was 1.27 mm (range, 0.78-1.63 mm). Within the knee, the thinnest areas of cartilage, and therefore closest matches, were discovered at the posterior pole of the medial femoral condyle (mean ± SD, 1.95 ± 0.46 mm) and at the distal-most anterior-lateral femoral condyle (1.85 ± 0.46 mm). The average variance between the mean cartilage depths measured by each investigator for each location was 0.12 mm in the elbow and 0.22 mm in

  12. Effectiveness of Lavage Techniques in Removing Immunogenic Elements from Osteochondral Allografts.

    PubMed

    Meyer, Maximilian A; McCarthy, Mark A; Gitelis, Matthew E; Poland, Sarah G; Urita, Atsushi; Chubinskaya, Susan; Yanke, Adam B; Cole, Brian J

    2017-10-01

    Objective This study aimed to compare standard saline lavage to combination saline and high-pressure carbon dioxide (CO2) lavage in removing marrow elements from osteochondral allografts. Design Six fresh hemicondyles were obtained. Three osteochondral allograft plugs (15-mm diameter, 6-mm depth) were harvested from each hemicondyle and randomized to 1 of 3 treatment arms: A, no lavage; B, 1 L standard saline lavage; C, simultaneous saline (1 L) and 1-minute high-pressure CO2 lavage. After hematoxylin and eosin staining, a "percentage fill" of remaining marrow elements was calculated for each overall sample and then repeated in 3 distinct compartments for each sample based on depth from surface: 1, deepest third; 2, middle third; and 3, most superficial third. Trial arms B and C were compared with 1-tailed Student t tests. Results Group A had an overall percentage fill of 51.2% ± 8.8%. While both lavage techniques decreased overall remaining marrow elements, group B yielded significantly higher percentages of remaining marrow elements than group C (28.6% ± 16.5%, 14.6% ± 8.7%, P = 0.045). On depth analysis, group A exhibited homogenous filling of trabecular space (63.0% ± 15.5%, 67.6% ± 13.7%, and 55.2% ± 10.1% in zones 1, 2, and 3, respectively). Both lavage arms equally removed marrow elements from superficial zone 3 (B, 17.4% ± 9.2%; C, 15.6% ± 12.4%, P = 0.41) and middle zone 2 (B, 30.2% ± 17.7%; C, 21.4% ± 15.5%, P = 0.18). However, group C lavage removed significantly more marrow elements in deep zone 1 than group B (29.7% ± 10.9%, 58.5% ± 25.2%, P = 0.01). Conclusion Combination saline and high-pressure CO2 lavage more effectively clears marrow elements from osteochondral allografts than saline alone.

  13. Novel Application of Magnetic Resonance Imaging Demonstrates Characteristic Differences in Vasculature at Predilection Sites of Osteochondritis Dissecans

    PubMed Central

    Tóth, Ferenc; Nissi, Mikko J.; Ellermann, Jutta M.; Wang, Luning; Shea, Kevin G.; Polousky, John; Carlson, Cathy S.

    2016-01-01

    Background Understanding the pathogenesis of osteochondrosis/osteochondritis dissecans and other developmental orthopaedic diseases that are thought to occur secondary to defects in vascular supply to growth/epiphyseal cartilage has been hampered by the inability to image the vasculature in this tissue. This is particularly true in human beings due to limitations of current imaging techniques and the lack of availability of appropriate cadaveric samples for histological studies. Hypothesis Susceptibility weighted imaging, an MRI sequence, allows identification of characteristic differences in the vascular architecture in species that are affected by osteochondrosis/osteochondritis dissecans on the femoral condyle (humans and pigs) versus one that is free of the disease (goat). Study design Descriptive laboratory study Materials Distal femora from cadavers of juvenile humans (n=5), pigs (n=3), and goats (n=3) were scanned in a 9.4T MRI scanner using susceptibility weighted imaging. Three-dimensional reconstructions were created and minimum intensity projections were calculated in three planes to enhance visualization of the vascular architecture. Results Susceptibility weighted imaging allowed clear visualization of the epiphyseal vasculature in all species. Vascular architecture, with vessels primarily arising from the perichondrium, was similar in humans and pigs, which are predisposed to osteochondrosis/osteochondritis dissecans, and was starkly different from that present in goats, a species in which there are no reports of osteochondrosis/osteochondritis dissecans. Furthermore, vessels in the distal femoral predilection site disappeared with age in a similar pattern in humans as has been reported previously in pigs. Conclusion Nearly identical vascular architecture at the shared primary predilection site of osteochondrosis/osteochondritis dissecans in the femoral condyles in human beings and pigs suggests that vascular failure, which is known to be central to

  14. Scaphoid reconstruction by a free vascularized osteochondral graft from the rib: a case report.

    PubMed

    Lanzetta, Marco

    2009-01-01

    Nonunion and avascular necrosis of the proximal pole of the scaphoid remain one of the most difficult problems in wrist reconstructive surgery. A number of interpositional vascularized bone grafts have been proposed for scaphoid nonunion, in order to promote faster union at the contact site with both fragments. However, once the proximal pole has undergone avascular changes and is completely necrotic, there is no alternative other than to remove it. At present, more radical operations have been advocated in these cases, such as proximal row carpectomy or intercarpal arthrodesis. We present a case where the necrotic proximal pole of the scaphoid was removed and replaced with a remodeled osteochondral-free vascularized graft from the rib based on the inferior and superior intercostal arteries, branches of the internal mammary artery.

  15. From loose body to osteochondritis dissecans: a historical account of disease definition

    PubMed Central

    TARABELLA, VITTORIO; FILARDO, GIUSEPPE; DI MATTEO, BERARDO; ANDRIOLO, LUCA; TOMBA, PATRIZIA; VIGANÒ, ANNA; MARCACCI, MAURILIO

    2016-01-01

    Osteochondritis dissecans (OCD) is a rare yet fascinating disease affecting young, active patients. It remains a ‘mysterious disease’ whose etiopathology, still unclear, is the subject of ongoing studies aiming improving the knowledge of this condition and, therefore, treatment options, too. Even though the first descriptions of intra-articular loose bodies date back to very ancient times, it is only relatively recently that, thanks to the contribution of some very eminent physicians, it became recognized as a specific orthopaedic condition. The aim of the present manuscript is to trace the main steps in the journey that led to the acknowledgement of OCD as an autonomous clinical entity, and to recall the prominent figures involved. PMID:27900309

  16. Gadopentetate-dimeglumine-enhanced MR imaging of osteonecrosis and osteochondritis dissecans of the elbow: initial experience.

    PubMed

    Peiss, J; Adam, G; Casser, R; Urhahn, R; Günther, R W

    1995-01-01

    Magnetic resonance imaging (MRI) was performed on seven patients with aseptic osteonecrosis (n = 4) and osteochondritis dissecans (OCD; n = 3) of the elbow. Precontrast MRI was superior to plain radiographs, which did not show any abnormality in three cases of osteonecrosis. On gadopentetate-dimeglumine-enhanced T1-weighted images, which were obtained in three patients with osteonecrosis and three patients with OCD, all cases of osteonecrosis demonstrated homogeneous enhancement of the lesions. All cases of OCD were diagnosed on plain radiographs. On MRI one showed significant enhancement of the loose body. In another case an incompletely enhancing loose body was surrounded by a diffusely enhancing region. In the third patient only a small marginal enhancement of the defect was observed. Our results suggest that MRI can improve the accuracy in diagnosis of aseptic osteonecrosis of the elbow. The use of gadopentetate dimeglumine allows the viability of the lesions or the loose bodies to be demonstrated and reparative tissue to be detected.

  17. Return to Sport After Operative Management of Osteochondritis Dissecans of the Capitellum

    PubMed Central

    Westermann, Robert W.; Hancock, Kyle J.; Buckwalter, Joseph A.; Kopp, Benjamin; Glass, Natalie; Wolf, Brian R.

    2016-01-01

    Background: Capitellar osteochondritis dissecans (OCD) is commonly managed surgically in symptomatic adolesent throwers and gymnasts. Little is known about the impact that surgical technique has on return to sport. Purpose: To evaluate the clinical outcomes and return-to-sport rates after operative management of OCD lesions in adolescent athletes. Study Design: Systematic review; Level of evidence, 4. Methods: The PubMed, CINAHL, EMBASE, SPORTDiscus (EBSCO), and Cochrane Central Register of Controlled Trials databases were queried for studies evaluating outcomes and return to sport after surgical management of OCD of the capitellum. Two independent reviewers conducted a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies reporting patient outcomes with return-to-sport data and minimum 6-month follow-up were included in the review. Results: After review, 24 studies reporting outcomes in 492 patients (mean age ± SD, 14.3 ± 0.9 years) were analyzed. The overall return-to-sport rate was 86% at a mean 5.6 months. Return to the highest preoperative level of sport was most common after osteochondral autograft procedures (94%) compared with debridement and marrow stimulation procedures (71%) or OCD fixation surgery (64%). Elbow range of motion improved by 15.9° after surgery. The Timmerman-Andrews subjective and objective scores significantly improved after surgery. Complications were low (<5%), with 2 cases of donor site morbidity after osteoarticular autograft transfer (OAT) autograft harvest. The most common indications for reoperation were repeat debridement/loose body removal. Conclusion: A high rate of return to sport was observed after operative management of capitellar OCD. Patients were more likely to return to their highest level of preoperative sport after OAT autograft compared with debridement or fixation. Significant improvements in elbow range of motion and patient outcomes are

  18. The contribution of bone and cartilage to the near-infrared spectrum of osteochondral tissue

    PubMed Central

    McGoverin, Cushla M.; Lewis, Karl; Yang, Xu; Bostrom, Mathias P. G.; Pleshko, Nancy

    2014-01-01

    Near-infrared (NIR) spectroscopy has been utilized to assess hyaline cartilage quality in human and animal osteochondral tissues. However, due to the lack of NIR signal from bone phosphate, and the relatively deep penetration depth of the radiation, the separate contributions of cartilage and bone to the spectral signatures have not been well defined. The objectives of the current study were 1) to improve the understanding of the contributions of bone and cartilage to NIR spectra acquired from osteochondral tissue, and 2) to assess the ability of this non-destructive method to predict cartilage thickness and modified Mankin grade of human tibial plateau articular cartilage. NIR spectra were acquired from samples of bovine bone and cartilage with varying thicknesses, and from twenty-two tibial plateaus harvested from patients undergoing knee replacement surgery. Spectra were recorded from regions of the tibial plateaus with varying degrees of degradation, and the cartilage thickness and modified Mankin grade of these regions were assessed histologically. Spectra from bone and cartilage samples of known thicknesses were investigated to identify spectral regions that were distinct for these two tissues. Univariate and multivariate linear regression methods were used to correlate modified Mankin grade and cartilage thickness with NIR spectral changes. The ratio of the NIR absorbances associated with water at 5270 and 7085 cm−1 were the best differentiator of cartilage and bone spectra. NIR prediction models for thickness and Mankin grade calculated using partial least squares regression were more accurate than univariate-based prediction models, with root mean square errors of cross validation of 0.42 mm (thickness) and 1.3 (modified Mankin grade), respectively. We conclude that NIR spectroscopy may be used to simultaneously assess articular cartilage thickness and modified Mankin grade, based in part on differences in spectral contributions from bone and cartilage

  19. Prevalence and Clinical Characteristics of Osteochondritis Dissecans of the Humeral Capitellum Among Adolescent Baseball Players.

    PubMed

    Kida, Yoshikazu; Morihara, Toru; Kotoura, Yoshihiro; Hojo, Tatsuya; Tachiiri, Hisakazu; Sukenari, Tsuyoshi; Iwata, Yoshio; Furukawa, Ryuhei; Oda, Ryo; Arai, Yuji; Fujiwara, Hiroyoshi; Kubo, Toshikazu

    2014-08-01

    The prevalence and clinical characteristics of osteochondritis dissecans (OCD) of the humeral capitellum among adolescent baseball players are unknown. To determine the OCD prevalence in adolescent competitive baseball players and to investigate the clinical characteristics of these patients. Cross-sectional and case-control study; Level of evidence, 3. A total of 2433 baseball players (mean age, 14.5 ± 1.5 years) belonging to junior high school and high school baseball clubs were enrolled. Players completed a questionnaire, and the elbow of each player's throwing arm was assessed by ultrasonography. Participants with abnormal results on ultrasonography were further examined through radiographic study. The OCD lesions were classified into stages based on radiographic results, and demographic data were compared between players with and without OCD lesions. Osteochondritis dissecans of the humeral capitellum was found in 82 (3.4%) elbows by ultrasonography. Players with an OCD lesion began playing baseball at an earlier age (P = .016), had a longer duration of competitive play (P = .0013), and had experienced more present (P = .0025) and past (P < .0001) elbow pain compared with players without a lesion. There were no differences between the 2 groups in the position played (P = .26). Sixty-eight patients underwent further radiographic examination for OCD (radiography, computed tomography, magnetic resonance imaging). Of these players, 10 (14.7%) were classified as having stage I OCD (radiolucent stage); 26 (38.2%), stage II (fragmentation stage); 9 (13.2%), stage III (loose body stage); 9 (13.2%), stage IV (residual stage); and 14 (23.5%), stage V (postoperative stage). The prevalence of OCD of the humeral capitellum, including latent cases, was 3.4% among adolescent baseball players. Players with OCD lesions began playing baseball at earlier ages, had played for longer periods, and had experienced more elbow pain. The player's current baseball position may not be

  20. The osteochondral ligament: a fibrous attachment between bone and articular cartilage in Rana catesbeiana.

    PubMed

    Felisbino, S L; Carvalho, H F

    2000-12-01

    The anuran epiphyseal cartilage shows a lateral expansion that covers the external surface of the bone, besides other features that distinguish it from the corresponding avian and mammalian structures. The fibrous structure that attaches the lateral cartilage to the bone was characterized in this work. It was designated osteochondral ligament (OCL) and presented two main areas. There was an inner area that was closer to the periosteal bone and contained a layer of osteoblasts and elongated cells aligned to and interspersed with thin collagen fibers. The thin processes of the cells in this area showed strong alkaline phosphatase activity. The outer area, which was closer to the cartilage, was rich in blood vessels and contained a few cells amongst thick collagen fibers. TRITC-phaloidin staining showed the cells of the inner area to be rich in F-actin, and were observed to form a net around the cell nucleus and to fill the cell processes which extended between the collagen fibers. Cells of the outer area were poor in actin cytoskeleton, while those associated with the blood vessels showed intense staining. Tubulin-staining was weak, regardless of the OCL region. The main fibers of the extracellular matrix in the OCL extended obliquely upwards from the cartilage to the bone. The collagen fibers inserted into the bone matrix as Sharpey's fibers and became progressively thicker as they made their way through the outer area to the cartilage. Immunocytochemistry showed the presence of type I and type III collagen. Microfibrils were found around the cells and amongst the collagen fibrils. These microfibrils were composed of either type VI collagen or fibrilin, as shown by immunocytochemistry. The results presented in this paper show that the osteochondral ligament of Rana catesbeiana is a complex and specialized fibrous attachment which guarantees a strong and flexible anchorage of the lateral articular cartilage to the periosteal bone shaft, besides playing a role in bone

  1. Femoral osteochondritis of the knee: prognostic value of the mechanical axis.

    PubMed

    Gonzalez-Herranz, P; Rodriguez, M L; de la Fuente, C

    2017-01-01

    Femoral osteochondritis dissecans (OCD) is a disorder of unknown aetiology and variable prognosis that causes knee pain. In this paper, the authors study the impact of lower limb malalignment on the development and prognosis of OCD. After anteroposterior (AP) and lateral radiograph and MRI of the knee, 53 cases of OCD were diagnosed. All patients were studied by standing full-length AP radiograph of the lower extremities in order to analyse the relationship between the femorotibial and mechanical axis and the location and stability of the osteochondritis. The OCD lesion was located in the medial condyle (zone 2) in 75.5% of cases (40 cases). The lateral condyle was affected in 24.5% of cases (zone 4 in nine cases and zone 5 in four cases). The femorotibial angle (anatomical axis) was normally aligned in 68% of cases. A valgus deformity was observed in 9.5% of cases and a varus deformity in 22.5%. The mechanical axis of the limb appeared normal in only 32% of cases, with medial deviation in 53%, and lateral deviation in 15% of cases. When the OCD lesion was located in the medial condyle (40 cases), the mechanical axis also crossed the knee through the medial zone in 28 cases. When the OCD lesion was located in the lateral condyle (13 cases), the mechanical axis crossed the knee through zones 1 or 2 in four cases. In stable OCD, the mechanical axis and location of the lesion coincided in 19 of 36 cases (52%), compared with 16 of 17 cases (94%) in unstable OCD. There is a high correlation between OCD location and lower limb mechanical axis deviation. The convergence of the mechanical axis with the location of the OCD lesion may be considered an associated factor in fragment instability. This convergence is more common in unstable OCD.

  2. Osteochondritis dissecans and Osgood Schlatter disease in a family with Stickler syndrome

    PubMed Central

    Al Kaissi, Ali; Klaushofer, Klaus; Grill, Franz

    2009-01-01

    Purpose Stickler syndrome is among the most common autosomal dominant connective tissue disorders but is often unrecognised and therefore not diagnosed by clinicians. Despite much speculation, the cause of osteochondrosis in general and osteochondritis dissecans (OCD) and Osgood Schlatter syndrome (OSS) in particular remain unclear. Etiological understanding is essential. We describe a pair of family subjects presented with OCD and OSS as a symptom complex rather than a diagnosis. Methods Detailed clinical and radiographic examinations were undertaken with emphasis on the role of MRI imaging. Magnetic resonance imaging may allow early prediction of articular lesion healing potential in patients with Stickler syndrome. Results The phenotype of Stickler syndrome can be diverse and therefore misleading. The expectation that the full clinical criteria of any given genetic disorder such as Stickler syndrome will always be present can easily lead to an underestimation of these serious inheritable disorders. We report here two family subjects, a male proband and his aunt (paternal sister), both presented with the major features of Stickler syndrome. Tall stature with marfanoid habitus, astigmatism/congenital vitreous abnormality and submucus cleft palate/cleft uvula, and enlarged painful joints with early onset osteoarthritis. Osteochondritis dissecans (OCD) and Osgood Schlatter syndrome (OSS) were the predominating joint abnormalities. Conclusion We observed that the nature of the articular and physeal abnormalities was consistent with a localised manifestation of a more generalised epiphyseal dysplasia affecting the weight-bearing joints. In these two patients, OCD and OSS appeared to be the predominant pathologic musculoskeletal consequences of an underlying Stickler's syndrome. It is empirical to consider generalised epiphyseal dysplasia as a major underlying causation that might drastically affect the weight-bearing joints. PMID:19193224

  3. Non-destructive monitoring of viability in an ex vivo organ culture model of osteochondral tissue.

    PubMed

    Elson, K M; Fox, N; Tipper, J L; Kirkham, J; Hall, R M; Fisher, J; Ingham, E

    2015-06-30

    Organ culture is an increasingly important tool in research, with advantages over monolayer cell culture due to the inherent natural environment of tissues. Successful organ cultures must retain cell viability. The aim of this study was to produce viable and non-viable osteochondral organ cultures, to assess the accumulation of soluble markers in the conditioned medium for predicting tissue viability. Porcine femoral osteochondral plugs were cultured for 20 days, with the addition of Triton X-100 on day 6 (to induce necrosis), camptothecin (to induce apoptosis) or no toxic additives. Tissue viability was assessed by the tissue destructive XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxyanilide tetrazolium salt) assay method and LIVE/DEAD® staining of the cartilage at days 0, 6 and 20. Tissue structure was assessed by histological evaluation using haematoxylin & eosin and safranin O. Conditioned medium was assessed every 3-4 days for glucose depletion, and levels of lactate dehydrogenase (LDH), alkaline phosphatase (AP), glycosaminoglycans (GAGs), and matrix metalloproteinase (MMP)-2 and MMP-9. Necrotic cultures immediately showed a reduction in glucose consumption, and an immediate increase in LDH, GAG, MMP-2 and MMP-9 levels. Apoptotic cultures showed a delayed reduction in glucose consumption and delayed increase in LDH, a small rise in MMP-2 and MMP-9, but no significant effect on GAGs released into the conditioned medium. The data showed that tissue viability could be monitored by assessing the conditioned medium for the aforementioned markers, negating the need for tissue destructive assays. Physiologically relevant whole- or part-joint organ culture models, necessary for research and pre-clinical assessment of therapies, could be monitored this way, reducing the need to sacrifice tissues to determine viability, and hence reducing the sample numbers necessary.

  4. Implantable Microimagers

    PubMed Central

    Ng, David C.; Tokuda, Takashi; Shiosaka, Sadao; Tano, Yasuo; Ohta, Jun

    2008-01-01

    Implantable devices such as cardiac pacemakers, drug-delivery systems, and defibrillators have had a tremendous impact on the quality of live for many disabled people. To date, many devices have been developed for implantation into various parts of the human body. In this paper, we focus on devices implanted in the head. In particular, we describe the technologies necessary to create implantable microimagers. Design, fabrication, and implementation issues are discussed vis-à-vis two examples of implantable microimagers; the retinal prosthesis and in vivo neuro-microimager. Testing of these devices in animals verify the use of the microimagers in the implanted state. We believe that further advancement of these devices will lead to the development of a new method for medical and scientific applications. PMID:27879873

  5. Surface modification by nitrogen plasma immersion ion implantation into new steel 460Li-21Cr in a capacitively coupled radio frequency discharge

    NASA Astrophysics Data System (ADS)

    Bhuyan, H.; Mändl, S.; Bora, B.; Favre, M.; Wyndham, E.; Maze, J. R.; Walczak, M.; Manova, D.

    2014-10-01

    A novel steel 460Li-21Cr belonging to a new generation of superferritic grade steel has been implanted with nitrogen in a low power 13.56 MHz radio frequency plasma by the plasma immersion ion implantation (PIII) technique in order to study its physical and chemical properties under different experimental conditions. We observed improved hardness and wear behavior of 460Li-21Cr steel with a layer thickness between 1.5 and 4.0 μm after 60 min implantation in the temperature range from 350 to 550 °C. The modified surface layer containing nitrogen does not show CrN in X-ray diffraction (XRD). Compared to untreated substrates, the hardness can be increased by a factor of 4, depending on the experimental conditions, and the wear behavior was also improved by two orders of magnitude. The results are very similar to those for austenitic stainless steel with a similar pronounced increase in wear resistance and plateau-like nitrogen depth profiles.

  6. High Productivity Implantation ''PARTIAL IMPLANT''

    SciTech Connect

    Hino, Masayoshi; Miyamoto, Naoki; Sakai, Shigeki; Matsumoto, Takao

    2008-11-03

    The patterned ion implantation 'PARTIAL IMPLANT' has been developed as a productivity improvement tool. The Partial Implant can form several different ion dose areas on the wafer surface by controlling the speed of wafer moving and the stepwise rotation of twist axis. The Partial Implant system contains two implant methods. One method is 'DIVIDE PARTIAL IMPLANT', that is aimed at reducing the consumption of the wafer. The Divide Partial Implant evenly divides dose area on one wafer surface into two or three different dose part. Any dose can be selected in each area. So the consumption of the wafer for experimental implantation can be reduced. The second method is 'RING PARTIAL IMPLANT' that is aimed at improving yield by correcting electrical characteristic of devices. The Ring Partial Implant can form concentric ion dose areas. The dose of wafer external area can be selected to be within plus or minus 30% of dose of wafer central area. So the electrical characteristic of devices can be corrected by controlling dose at edge side on the wafer.

  7. Clinical and imaging outcome of osteochondral lesions of the talus treated using autologous matrix-induced chondrogenesis technique with a biomimetic scaffold.

    PubMed

    Albano, Domenico; Martinelli, Nicolò; Bianchi, Alberto; Messina, Carmelo; Malerba, Francesco; Sconfienza, Luca Maria

    2017-07-18

    The purpose of our study was to assess the clinical and imaging outcome of autologous matrix-induced chondrogenesis (AMIC) technique consisting of microfractures followed by the filling of osteochondral lesions of the talus (OLTs) with a cell-free biphasic collagen-hydroxyapatite osteochondral scaffold (MaioRegen). Sixteen patients (eight males, age: 42.6 ± 18.4, range 14-74) with OLT repaired using AMIC technique, with implantation of MaioRegen, were clinically evaluated through the American Orthopedic Foot and Ankle Society Score (AOFAS) and a 10-point Visual Analogue Scale (VAS) pain score after a mean follow-up of 30 ± 16.9 months. The MRI examinations were performed 12 and 24 months after surgery. A paired t-test was applied to compare pre- and post-operative clinical findings (VAS and AOFAS) and Magnetic resonance observation of cartilage repair tissue (MOCART) score changes in the follow-up. To assess the correlation between variation of AOFAS and MOCART scores, the Pearson's correlation coefficient was calculated. No complications after surgery were encountered. From pre-operative to post-operative values, there was a significant (P < 0.001) reduction of mean VAS pain score (6.3 ± 0.9,range: 4-8 and 2.9 ± 1.8,range: 0-6, respectively) and increase of AOFAS score (60.2 ± 7.8,range: 50-74 and 77.4 ± 16.2,range: 50-100, respectively). Among 16 patients, six (37%) were not satisfied at the end of follow-up, six (37%) were moderately satisfied and four (25%) were highly satisfied. The treatment was considered failed in five out of 16 patients (31%). Among them, four (25%) required re-interventions with implantation of ankle prostheses, whereas one patient was treated with a further AMIC technique combined with autologous bone graft and platelet-rich plasma. The mean MOCART score was 41.9 ± 14.6 (25-70) 12 months after surgery and 51.9 ± 11.6 (30-70) after 24 months, with a statistically significant increase (P = 0.012). However

  8. Endodontic implants

    PubMed Central

    Yadav, Rakesh K.; Tikku, A. P.; Chandra, Anil; Wadhwani, K. K.; Ashutosh kr; Singh, Mayank

    2014-01-01

    Endodontic implants were introduced back in 1960. Endodontic implants enjoyed few successes and many failures. Various reasons for failures include improper case selection, improper use of materials and sealers and poor preparation for implants. Proper case selection had given remarkable long-term success. Two different cases are being presented here, which have been treated successfully with endodontic implants and mineral trioxide aggregate Fillapex (Andreaus, Brazil), an MTA based sealer. We suggest that carefully selected cases can give a higher success rate and this method should be considered as one of the treatment modalities. PMID:25298723

  9. Transplant of mesenchymal stem cells and hydroxyapatite ceramics to treat severe osteochondral damage after septic arthritis of the knee.

    PubMed

    Adachi, Nobuo; Ochi, Mitsuo; Deie, Masataka; Ito, Yohei

    2005-08-01

    We describe a 21-year-old man with a large osteochondral defect of the knee after septic arthritis, successfully treated by transplant of mesenchymal stem cells (MSC) from bone marrow and a new type of interconnected porous hydroxyapatite ceramic (IP-CHA). We confirmed successful cartilage-like tissue regeneration by a second arthroscopy. Biopsy of the repaired tissue revealed cartilage-like regeneration and bone formation. We were able to regenerate new bone and cartilage-like tissue in a one-stage operation, without sacrificing autologous bone or other tissue. This cultured MSC and IP-CHA hybrid material transplant represents a novel treatment for a severe osteochondral defect after septic arthritis.

  10. Surgical treatment of an osteochondral lesion associated with stress fracture of the tarsal navicular: a case report.

    PubMed

    Kanazawa, Kazuki; Yoshimura, Ichiro; Shiokawa, Teruaki; Hagio, Tomonobu; Naito, Masatoshi

    2013-01-01

    We surgically treated an osteochondral lesion associated with a stress fracture of the tarsal navicular. The surgical procedure involved the confirmation and complete resection of the lesion under direct vision, followed by the transplantation of block-shaped iliac bone grafts. The postoperative computed tomography scan showed that the lesions had disappeared, the grafted bone had fused, and the stress fracture had healed. However, the tarsal navicular joint surface was slightly irregular. The patient was able to resume her sports activities 15 weeks after surgery. We have described a novel method to reconstruct the tarsal navicular after osteochondral lesion resection. Copyright © 2013 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  11. Osteochondral Tissue Engineering In Vivo: A Comparative Study Using Layered Silk Fibroin Scaffolds from Mulberry and Nonmulberry Silkworms

    PubMed Central

    Saha, Sushmita; Kundu, Banani; Kirkham, Jennifer; Wood, David; Kundu, Subhas C.; Yang, Xuebin B.

    2013-01-01

    The ability to treat osteochondral defects is a major clinical need. Existing polymer systems cannot address the simultaneous requirements of regenerating bone and cartilage tissues together. The challenge still lies on how to improve the integration of newly formed tissue with the surrounding tissues and the cartilage-bone interface. This study investigated the potential use of different silk fibroin scaffolds: mulberry (Bombyx mori) and non-mulberry (Antheraea mylitta) for osteochondral regeneration in vitro and in vivo. After 4 to 8 weeks of in vitro culture in chondro- or osteo-inductive media, non-mulberry constructs pre-seeded with human bone marrow stromal cells exhibited prominent areas of the neo tissue containing chondrocyte-like cells, whereas mulberry constructs pre-seeded with human bone marrow stromal cells formed bone-like nodules. In vivo investigation demonstrated neo-osteochondral tissue formed on cell-free multi-layer silk scaffolds absorbed with transforming growth factor beta 3 or recombinant human bone morphogenetic protein-2. Good bio-integration was observed between native and neo-tissue within the osteochondrol defect in patellar grooves of Wistar rats. The in vivo neo-matrix formed comprised of a mixture of collagen and glycosaminoglycans except in mulberry silk without growth factors, where a predominantly collagenous matrix was observed. Immunohistochemical assay showed stronger staining of type I and type II collagen in the constructs of mulberry and non-mulberry scaffolds with growth factors. The study opens up a new avenue of using inter-species silk fibroin blended or multi-layered scaffolds of a combination of mulberry and non-mulberry origin for the regeneration of osteochondral defects. PMID:24260335

  12. Diagnostic sensitivity of radiography, ultrasonography, and magnetic resonance imaging for detecting shoulder osteochondrosis/osteochondritis dissecans in dogs.

    PubMed

    Wall, Corey R; Cook, Cristi R; Cook, James L

    2015-01-01

    Radiography, magnetic resonance imaging (MRI), and ultrasonography are commonly used for diagnosis of shoulder osteochondrosis and osteochondritis dissecans (OC/OCD) in dogs, however there is a lack of published information on the relative diagnostic sensitivities of these modalities. The purpose of this prospective study was to compare diagnostic sensitivities of these modalities for detecting shoulder OC/OCD in a group of dogs, using arthroscopy as the reference standard. Inclusion criteria were history and clinical findings consistent with osteochondrosis and/or osteochondritis dissecans involving at least one shoulder. With informed client consent, both shoulders for all included dogs were examined using standardized radiography, ultrasonography, MRI, and arthroscopy protocols. One of three veterinary surgeons recorded clinical and arthroscopic findings without knowledge of diagnostic imaging findings. One of two veterinary radiologists recorded diagnostic imaging findings without knowledge of clinical and arthroscopic findings. Eighteen client-owned dogs (n = 36 shoulders) met inclusion criteria. Diagnostic sensitivity, specificity, and accuracy (correct classification rate) values for detecting presence or absence of shoulder osteochondrosis/osteochondritis dissecans were as follows: radiography (88.5%, 90%, 88.9%), ultrasonography (92%, 60%, 82.6%), and MRI (96%, 88.9%, 94.4%). Odds of a correct diagnosis for MRI were 3.2 times more than ultrasonography and two times more than radiography. For MRI detection of lesions, the sagittal T2 or PD-FAT SAT sequences were considered to be most helpful. For radiographic detection of lesions, the additional supinated-mediolateral and pronated-mediolateral projections were considered to be most helpful. Findings from the current study support more evidence-based diagnostic imaging recommendations for dogs with clinically suspected shoulder osteochondrosis or osteochondritis dissecans. © 2014 American College of

  13. Does extracorporeal shock wave therapy enhance healing of osteochondritis dissecans of the rabbit knee?: a pilot study.

    PubMed

    Lyon, Roger; Liu, Xue Cheng; Kubin, Martin; Schwab, Joseph

    2013-04-01

    Severe osteochondritis dissecans (OCD) in children and adolescents often necessitates surgical interventions (ie, drilling, excision, or débridement). Since extracorporeal shock wave therapy (ESWT) enhances healing of long-bone nonunion fractures, we speculated ESWT would reactivate the healing process in OCD lesions. We asked whether ESWT would enhance articular cartilage quality, bone and cartilage density, and histopathology of osteochondral lesions compared to nontreated controls in an OCD rabbit model. We harvested a 4-mm-diameter plug of the weightbearing osteochondral surface on the medial femoral condyle of each knee in 20 skeletally immature (8-week-old) female rabbits. We placed a piece of acellular collagen-glycosaminoglycan matrix into the cavity and then replaced the plug. Two weeks after surgery, we sedated each rabbit and treated the right knee in a single setting with shock waves: 4000 impulses at 4 Hz and 18 kV. The left knee was a sham control. Ten weeks after surgery, we assessed cartilage morphology of the lesion using a modified Outerbridge Grading System, bone and cartilage density using histologic imaging, bone and cartilage morphology using the histopathology assessment system, and radiographic bone density and union and compared these parameters between ESWT-treated and control knees. Histologically, we observed more mature bone formation and better healing (1.1 versus 3.4) and density of the cartilage (60 versus 49) on the treated side. Radiographically, we noted an increase in bony density (154 versus 138) after ESWT. ESWT accelerated the healing rate and improved cartilage and subchondral bone quality in the OCD rabbit model. This therapeutic modality may be applicable in OCD treatment in the pediatric population. Future research will be necessary to determine whether it may play a role in healing of human osteochondral defects.

  14. Effect of insulin-like growth factor-1 and hyaluronic acid in experimentally produced osteochondral defects in rats

    PubMed Central

    Alemdar, Celil; Yücel, İstemi; Erbil, Barış; Erdem, Havva; Atiç, Ramazan; Özkul, Emin

    2016-01-01

    Background: The common purpose of almost all methods used to treat the osteochondral injuries is to produce a normal cartilage matrix. However current methods are not sufficient to provide a normal cartilage matrix. For that reason, researchers have studied to increase the effectiveness of this methods using chondrogenic and chondroprotective molecules in recent experimental studies. Insulin-like growth factor-1 (IGF-1) and hyaluronic acid (HA) are two important agents used in this field. This study compared the effects of IGF-1 and HA in an experimental osteochondral defect in rat femora. Materials and Methods: The rats were divided into three groups (n = 15 per group) as follows: The IGF-1 group, HA group, and control group. An osteochondral defect of a diameter of 1.5 mm and a depth of 2 mm was created on the patellar joint side of femoral condyles. The IGF-1 group received an absorbable gelatin sponge soaked with 15 μg/15 μl of IGF-1, and the HA group received an absorbable gelatin sponge soaked with 80 μg HA. The control group received only an absorbable gelatin sponge. Rats were sacrificed at the 6th week, and the femur condyles were evaluated histologically. Results: According to the total Mankin scale, there was a statistically significant difference between IGF-1 and HA groups and between IGF-1 and control groups. There was also a significant statistical difference between HA and control groups. Conclusion: It was shown histopathologically that IGF-1 is an effective molecule for osteochondral lesions. Although it is weaker than IGF-1, HA also strengthened the repair tissue. PMID:27512224

  15. Combination of bone marrow mesenchymal stem cells and cartilage fragments contribute to enhanced repair of osteochondral defects.

    PubMed

    Abbas, Mohammed

    2017-01-01

    Cartilage tissue engineering using stem cells and biomaterials is considered a promising approach despite poor outcomes. We hypothesise that articular cartilage fragments provides native environmental cues to enhance stem cell differentiation. As such we evaluated the chondrogenic differentiation and repair of critical size defect in a human explant osteochondral model (OD) using bone marrow derived mesenchymal stem cells (BM-MSCs) and homogenised cartilage. BM-MSCs were established from the bone-marrow plugs of patients undergoing total knee arthroplasty and characterized. Osteochondral tissue was trimmed and a central drill defect (∼2mm) was made. Chondrogenic repair was evaluated by filling the OD defect area with either BM-MSCs (Group II), homogenized cartilage (Group III) or a combination of both BM-MSCs and homogenized cartilage (Group IV). OD with no added cell or tissue served as control (Group I). Samples were maintained in chondrogenic differentiation medium for 28 days. Microscopic images showed maximal OD closure in Group IV. Partial OD closure was observed in Group II and to a lesser extent in Group III. Haematoxylin-eosin staining revealed immature cartilaginous matrix in Group II and more mature matrix in Group IV. Sircol™ Assay showed increased collagen deposition in both Group II and Group IV. Immunostaining for both groups revealed positive staining for type II collagen. Combining BM-MSCs and homogenised cartilage demonstrated enhanced cartilage formation and defect filling in a human ex-vivo osteochondral model.

  16. About Implantable Contraception

    MedlinePlus

    ... TV, Video Games, and the Internet About Implantable Contraception KidsHealth > For Parents > About Implantable Contraception Print A ... How Much Does It Cost? What Is Implantable Contraception? Implantable contraception (often called the birth control implant) ...

  17. In vitro generation of whole osteochondral constructs using rabbit bone marrow stromal cells, employing a two-chambered co-culture well design.

    PubMed

    Chen, Kelei; Ng, Kian Siang; Ravi, Sujata; Goh, James C H; Toh, Siew Lok

    2016-04-01

    The regeneration of whole osteochondral constructs with a physiological structure has been a significant issue, both clinically and academically. In this study, we present a method using rabbit bone marrow stromal cells (BMSCs) cultured on a silk-RADA peptide scaffold in a specially designed two-chambered co-culture well for the generation of multilayered osteochondral constructs in vitro. This specially designed two-chambered well can simultaneously provide osteogenic and chondrogenic stimulation to cells located in different regions of the scaffold. We demonstrated that this co-culture approach could successfully provide specific chemical stimulation to BMSCs located on different layers within a single scaffold, resulting in the formation of multilayered osteochondral constructs containing cartilage-like and subchondral bone-like tissue, as well as the intermediate osteochondral interface. The cells in the intermediate region were found to be hypertrophic chondrocytes, embedded in a calcified extracellular matrix containing glycosaminoglycans and collagen types I, II and X. In conclusion, this study provides a single-step approach that highlights the feasibility of rabbit BMSCs as a single-cell source for multilayered osteochondral construct generation in vitro.

  18. Results of Bone Peg Grafting for Capitellar Osteochondritis Dissecans in Adolescent Baseball Players.

    PubMed

    Oshiba, Hiroyuki; Itsubo, Toshiro; Ikegami, Shota; Nakamura, Koichi; Uchiyama, Shigeharu; Kato, Hiroyuki

    2016-12-01

    Bone peg grafting (BPG) has been advocated for early-stage humeral capitellar osteochondritis dissecans (COCD). However, the clinical and radiological results of BPG, along with its indications, have not been described in detail. COCD classified as International Cartilage Repair Society (ICRS) osteochondritis dissecans (OCD) I or II in adolescent baseball players can be treated successfully by BPG. Case series; Level of evidence, 4 METHODS: Eleven male baseball players (age range at surgery, 13-16 years) who underwent BPG for COCD were enrolled in this study. No improvement had been seen in any patient after 6 months of preoperative nonthrowing observation. During surgery, 2 to 5 bone pegs were inserted into the COCD lesion after confirmation of lesion stability to the bony floor. All patients were directly evaluated at 12 and 24 months after surgery by physical findings, radiological prognosis, and magnetic resonance imaging (MRI). Of the 11 patients, 10 could return to comparable baseball ability levels within 12 months. The Timmerman-Andrews score improved significantly from a mean ± SD of 171.8 ± 12.1 preoperatively to 192.3 ± 6.5 at the final observation. Radiological healing of the lesions was determined as complete in 8 patients and partial in 3. Patients possessing a centrally positioned lesion or a lesion <75% of the size of the capitellum tended most strongly to achieve complete radiological healing, while growth plate status appeared unrelated to outcome. The mean Henderson MRI score improved from 6.3 ± 1.5 to 4.8 ± 1.6 at 12 and 24 months after BPG, respectively. MRI findings also suggested that remodeling of COCD lesions had continued to up to 24 months postoperatively. BPG enabled 91% of COCD patients with ICRS OCD I or II to return to preoperative baseball abilities within 12 months. Integration of the grafted site may continue until at least 24 months postoperatively. An ICRS OCD I or II lesion with central positioning and/or occupying <75% of

  19. The Incidence of Surgery in Osteochondritis Dissecans in Children and Adolescents

    PubMed Central

    Weiss, Jennifer M.; Nikizad, Hooman; Shea, Kevin G.; Gyurdzhyan, Samvel; Jacobs, John C.; Cannamela, Peter C.; Kessler, Jeffrey I.

    2016-01-01

    Background: The frequency of osteochondritis dissecans (OCD), a disorder of the subchondral bone and articular cartilage, is not well described. Purpose: To assess the frequency of pediatric OCD lesions that progress to surgery based on sex, joint involvement, and age. Study Design: Descriptive epidemiology study. Methods: A retrospective chart review (2007-2011) was performed on OCD. Inclusion criteria included OCD of any joint and patients aged 2 to 19 years. Exclusion criteria included traumatic osteochondral fractures or coexistence of non-OCD intra-articular lesions. Differences in progression toward surgery were compared between age groups, sex, and joint location. Logistical regression analysis was performed by sex, age, and ethnicity. Results: Overall, 317 patients with a total of 334 OCD lesions were found. The majority of lesions (61.7%) were in the knee, with ankle, elbow, shoulder, and foot lesions representing 25.4%, 12.0%, 0.6%, and 0.3% of all lesions, respectively. The majority of joints needing surgery were in the knee (58.5%), with ankle and elbow lesions representing 22.9% and 18.6% of surgeries performed, respectively. The percentage of all OCD lesions progressing to surgery was 35.3%; surgical progression for knee, ankle, and elbow joints was 33.5%, 31.8%, and 55.0%, respectively. Logistic regression analysis found no statistically significant different risk of progressing to surgery for OCD of the knee, elbow, and ankle between sexes. Patients aged 12 to 19 years had a 7.4-times greater risk of progression to surgery for knee OCD lesions than 6- to 11-year-olds. Patients aged 12 to 19 years were 8.2 times more likely to progress to surgery for all OCD lesions than patients aged 6 to 11 years. Progression to surgery of ankle OCD did not significantly differ based on location. Three of 4 trochlear lesions progressed to surgery, along with 1 of 1 tibial, 1 of 3 patellar, 40.3% of lateral femoral condylar, and 28.2% of medial femoral condylar

  20. Can Competitive Athletes Sustain High-Level Play Following Osteochondral Allograft Transplantation of the Knee?

    PubMed Central

    McCarthy, Mark A.; Meyer, Maximilian A.; Weber, Alexander E.; Levy, David; Tilton, Annemarie K.; Yanke, Adam Blair; Cole, Brian J.

    2017-01-01

    Objectives: The purpose of this study is to investigate the ability of competitive athletes to remain at a high level of competition following osteochondral allograft transplantation (OCA) of the knee. Methods: A retrospective review was performed to identify all competitive athletes (high school, collegiate, professional) who underwent an isolated femoral condyle OCA between 2004 and 2012. Patient reported outcome (PRO) questionnaires (Lysholm, International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMasters Universities Arthritis Index (WOMAC), Short Form-12 (SF-12), Tegner, and Marx) and custom return-to-sport surveys were administered. All subsequent reoperations were documented. Results: A total of 13 (7 male, 6 female) athletes were identified with an average follow-up of 5.9 ± 2.5 years. Four athletes competed at an intercollegiate level, while 9 played high-level high-school sports. Seven athletes returned to competitive sport (54%) at an average of 7.9 ± 3.5 months, five of whom were returned to pre-injury levels of play. Of the eight athletes who either did not return to sport or failed to sustain their high level of play, the most common reasons cited were a change in life circumstances, such as graduation, or a fear of re-injury (Figure 1). At final follow-up, regardless of return-to-play, all athletes had significant improvements in all PRO scores except for KOOS-Sport, WOMAC-Stiffness, and SF-12 Mental subscales. Tegner Activity scores dropped significantly from pre-injury to final follow-up (8.2 ± 2.4, 4.5 ± 2.1, p < 0.01). There were three reoperations and zero instances of graft failure. Conclusion: OCAs provide acceptable rates of return-to-play and excellent long-term outcomes for high-level athletes with large osteochondral defects. Social factors are three times more likely than persistent pain to prevent return to sport.

  1. First metatarsal head osteoarticular transfer system for salvage of a failed hemicap-implant: a case report.

    PubMed

    Hopson, Matthew; Stone, Paul; Paden, Matthew

    2009-01-01

    Osteochondral defects are frequently seen in patients with hallux limitus. Historically, such patients have been treated with cheilectomy, arthroplasty, osteotomy, fusion, and other joint destructive procedures. We present a case of a 54-year-old man who presented with a failed hemicap implant of the first metatarsal head. Seven months after his initial implant surgery, the patient was still experiencing pain and limited function despite conservative treatment efforts. In an effort to salvage the joint, an osteoarticular transfer system procedure was undertaken. After removal of the 12-mm hemicap implant, a 15 x 12 mm osteochondral plug was taken from the ipsilateral femoral condyle and press fit into the defect in the first metatarsal head. At 6 weeks postoperatively, complete consolidation of the graft was observed radiographically. By 6 months postoperatively, the patient was able to walk more than 15 miles per week without pain while wearing regular shoes. He was subsequently discharged at 1-year postoperatively, at which time he neither described nor demonstrated any signs or symptoms related to hallux limitus/rigidus. To our knowledge, this particular technique has not been previously reported for lesions of this size in the first metatarsal head. 4.

  2. Cochlear implant

    MedlinePlus

    ... bilateral cochlear implantation: a review. Curr Opin Otolaryngol Head Neck Surg . 2007;15(5):315-318. PMID: 17823546. ... BH, Lund V, et al, eds. Cummings Otolaryngology: Head & Neck Surgery . 6th ed. Philadelphia, PA: Elsevier Saunders; 2015: ...

  3. Histrelin Implant

    MedlinePlus

    ... implant (Supprelin LA) is used to treat central precocious puberty (CPP; a condition causing children to enter puberty too soon, resulting in faster than normal bone growth and development of sexual characteristics) in girls ...

  4. Breast Implants

    MedlinePlus

    ... in the United States: saline-filled and silicone gel-filled. Both types have a silicone outer shell. ... them. Provide information on saline-filled and silicone gel-filled breast implants, including data supporting a reasonable ...

  5. Cochlear implants.

    PubMed

    Connell, Sarah S; Balkany, Thomas J

    2006-08-01

    Cochlear implants are cost-effective auditory prostheses that safely provide a high-quality sensation of hearing to adults who are severely or profoundly deaf. In the past 5 years, progress has been made in hardware and software design, candidate selection, surgical techniques, device programming, education and rehabilitation,and, most importantly, outcomes. Cochlear implantation in the elderly is well tolerated and provides marked improvement in auditory performance and psychosocial functioning.

  6. Design parameters and the material coupling are decisive for the micromotion magnitude at the stem-neck interface of bi-modular hip implants.

    PubMed

    Jauch, S Y; Huber, G; Haschke, H; Sellenschloh, K; Morlock, M M

    2014-03-01

    Several bi-modular hip prostheses exhibit an elevated number of fretting-related postoperative complications most probably caused by excessive micromotions at taper connections. This study investigated micromotions at the stem-neck interface of two different designs: one design (Metha, Aesculap AG) has demonstrated a substantial number of in vivo neck fractures for Ti-Ti couplings, but there are no documented fractures for Ti-CoCr couplings. Conversely, for a comparable design (H-Max M, Limacorporate) with a Ti-Ti coupling only one clinical failure has been reported. Prostheses were mechanically tested and the micromotions were recorded using a contactless measurement system. For Ti-Ti couplings, the Metha prosthesis showed a trend towards higher micromotions compared to the H-Max M (6.5 ± 1.6 μm vs. 3.6 ± 1.5 μm, p=0.08). Independent of the design, prostheses with Ti neck adapter caused significantly higher interface micromotions than those with CoCr ones (5.1 ± 2.1 μm vs. 0.8 ± 1.6 μm, p=0.001). No differences in micromotions between the Metha prosthesis with CoCr neck and the H-Max M with Ti neck were observed (2.6 ± 2.0 μm, p=0.25). The material coupling and the design are both crucial for the micromotions magnitude. The extent of micromotions seems to correspond to the number of clinically observed fractures and confirm the relationship between those and the occurrence of fretting corrosion. Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.

  7. Contraceptive implants.

    PubMed

    McDonald-Mosley, Raegan; Burke, Anne E

    2010-03-01

    Implantable contraception has been extensively used worldwide. Implants are one of the most effective and reversible methods of contraception available. These devices may be particularly appropriate for certain populations of women, including women who cannot use estrogen-containing contraception. Implants are safe for use by women with many chronic medical problems. The newest implant, Implanon (Organon International, Oss, The Netherlands), is the only device currently available in the United States and was approved in 2006. It is registered for 3 years of pregnancy prevention. Contraceptive implants have failure rates similar to tubal ligation, and yet they are readily reversible with a return to fertility within days of removal. Moreover, these contraceptive devices can be safely placed in the immediate postpartum period, ensuring good contraceptive coverage for women who may be at risk for an unintended pregnancy. Irregular bleeding is a common side effect for all progestin-only contraceptive implants. Preinsertion counseling should address possible side effects, and treatment may be offered to women who experience prolonged or frequent bleeding.

  8. Rescuing failed oral implants via Wnt activation

    PubMed Central

    Yin, Xing; Li, Jingtao; Chen, Tao; Mouraret, Sylvain; Dhamdhere, Girija; Brunski, John B.; Zou, Shujuan; Helms, Jill A.

    2016-01-01

    Aim Implant osseointegration is not always guaranteed and once fibrous encapsulation occurs clinicians have few options other than implant removal. Our goal was to test whether a WNT protein therapeutic could rescue such failed implants. Material and Methods Titanium implants were placed in over-sized murine oral osteotomies. A lack of primary stability was verified by mechanical testing. Interfacial strains were estimated by finite element modelling and histology coupled with histomorphometry confirmed the lack of peri-implant bone. After fibrous encapsulation was established peri-implant injections of a liposomal formulation of WNT3A protein (L-WNT3A) or liposomal PBS (L-PBS) were then initiated. Quantitative assays were employed to analyse the effects of L-WNT3A treatment. Results Implants in gap-type interfaces exhibited high interfacial strains and no primary stability. After verification of implant failure, L-WNT3A or L-PBS injections were initiated. L-WNT3A induced a rapid, significant increase in Wnt responsiveness in the peri-implant environment, cell proliferation and osteogenic protein expression. The amount of peri-implant bone and bone in contact with the implant were significantly higher in L-WNT3A cases. Conclusions These data demonstrate L-WNT3A can induce peri-implant bone formation even in cases where fibrous encapsulation predominates. PMID:26718012

  9. Challenges in engineering osteochondral tissue grafts with hierarchical structures Ivana Gadjanski, Gordana Vunjak Novakovic

    PubMed Central

    Gadjanski, Ivana; Vunjak-Novakovic, Gordana

    2015-01-01

    Introduction A major hurdle in treating osteochondral (OC) defects are the different healing abilities of two types of tissues involved - articular cartilage and subchondral bone. Biomimetic approaches to OC-construct-engineering, based on recapitulation of biological principles of tissue development and regeneration, have potential for providing new treatments and advancing fundamental studies of OC tissue repair. Areas covered This review on state of the art in hierarchical OC tissue graft engineering is focused on tissue engineering approaches designed to recapitulate the native milieu of cartilage and bone development. These biomimetic systems are discussed with relevance to bioreactor cultivation of clinically sized, anatomically shaped human cartilage/bone constructs with physiologic stratification and mechanical properties. The utility of engineered OC tissue constructs is evaluated for their use as grafts in regenerative medicine, and as high-fidelity models in biological research. Expert opinion A major challenge in engineering OC tissues is to generate a functionally integrated stratified cartilage-bone structure starting from one single population of mesenchymal cells, while incorporating perfusable vasculature into the bone, and in bone-cartilage interface. To this end, new generations of advanced scaffolds and bioreactors, implementation of mechanical loading regimens, and harnessing of inflammatory responses of the host will likely drive the further progress. PMID:26195329

  10. Design of a multiphase osteochondral scaffold. II. Fabrication of a mineralized collagen-glycosaminoglycan scaffold.

    PubMed

    Harley, Brendan A; Lynn, Andrew K; Wissner-Gross, Zachary; Bonfield, William; Yannas, Ioannis V; Gibson, Lorna J

    2010-03-01

    This paper is the second in a series of papers describing the design and development of an osteochondral scaffold using collagen-glycosaminoglycan and calcium phosphate technologies engineered for the regenerative repair of articular cartilage defects. The previous paper described a technology (concurrent mapping) for systematic variation and control of the chemical composition of triple coprecipitated collagen, glycosaminoglycan, and calcium phosphate (CGCaP) nanocomposites without using titrants. This paper describes (1) fabricating porous, three-dimensional scaffolds from the CGCaP suspensions, (2) characterizing the microstructure and mechanical properties of such scaffolds, and (3) modifying the calcium phosphate mineral phase. The methods build on the previously demonstrated ability to vary the composition of a CGCaP suspension (calcium phosphate mass fraction between 0 and 80 wt %) and enable the production of scaffolds whose pore architecture (mean pore size: 50-1000 microm), CaP phase chemistry (brushite, octacalcium phosphate, apatite) and crosslinking density (therefore mechanical properties and degradation rate) can be independently controlled. The scaffolds described in this paper combine the desirable biochemical properties and pore architecture of porous collagen-glycosaminoglycan scaffolds with the strength and direct bone-bonding properties of calcium phosphate biomaterials in a manner that can be tailored to meet the demands of a range of applications in orthopedics and regenerative medicine.

  11. Diagnostic Value of CT Arthrography for Evaluation of Osteochondral Lesions at the Ankle

    PubMed Central

    Kirschke, Jan S.; Braun, Sepp; Baum, Thomas; Holwein, Christian; Schaeffeler, Christoph; Imhoff, Andreas B.; Rummeny, Ernst J.; Woertler, Klaus

    2016-01-01

    Background. To retrospectively determine the diagnostic value of computed tomography arthrography (CTA) of the ankle in the evaluation of (osteo)chondral lesions in comparison to conventional magnetic resonance imaging (MRI) and intraoperative findings. Methods. A total of N = 79 patients had CTAs and MRI of the ankle; in 17/79 cases surgical reports with statements on cartilage integrity were available. Cartilage lesions and bony defects at talus and tibia were scored according to defect depth and size by two radiologists. Statistical analysis included sensitivity analyses and Cohen's kappa calculations. Results. On CTA, 41/79 and 31/79 patients had full thickness cartilage defects at the talus and at the tibia, respectively. MRI was able to detect 54% of these defects. For the detection of full thickness cartilage lesions, interobserver agreement was substantial (0.72 ± 0.05) for CTA and moderate (0.55 ± 0.07) for MRI. In surgical reports, 88–92% and 46–62% of full thickness defects detected by CTA and MRI were described. CTA findings changed the further clinical management in 15.4% of cases. Conclusions. As compared to conventional MRI, CTA improves detection and visualization of cartilage defects at the ankle and is a relevant tool for treatment decisions in unclear cases. PMID:27891511

  12. Management strategies for osteochondritis dissecans of the knee in the skeletally immature athlete.

    PubMed

    Eismann, Emily A; Pettit, Robert J; Wall, Eric J; Myer, Gregory D

    2014-09-01

    Osteochondritis dissecans (OCD) is a disorder resulting in focal breakdown of the subchondral bone, with potential disruption of the overlying articular cartilage. The femoral condyles of the knee are the most common locations for OCD, and the incidence of OCD appears to be increasing among active children. Juvenile OCD (JOCD) can be distinguished from adult OCD by the presence of open growth plates. Due to a lack of evidence on its early diagnosis, optimal treatment, and long-term course of healing, JOCD presents a unique challenge for the health care team. Approximately 50% to 67% of stable JOCD lesions heal successfully with nonoperative treatment. For unstable lesions and stable lesions that fail nonoperative treatment, a variety of surgical interventions can be utilized to stimulate bony healing and address articular cartilage lesions. It is recommended that rehabilitation of JOCD be tailored to the individual patient, based on the stage and radiographic status of the lesion and the mode of surgery employed when surgically addressed. Although there is a growing body of literature on this condition, the etiology and optimal methods for treatment, rehabilitation, and evaluating outcomes remain inconclusive due to a lack of quality evidence. Therapy, level 5.

  13. Lunate Osteochondral Fracture Treated by Excision: A Case Report and Literature Review

    PubMed Central

    Saberi, Sadegh; Arabzadeh, Aidin; Farhoud, Amir Reza

    2016-01-01

    Introduction Lunate fracture is a rare injury. Most reports are associated with other wrist injuries such as perilunate dislocation and distal radius fracture. Isolated lunate fracture has been reported even more rarely. The choice of treatment and outcomes are consequently undetermined. Case Presentation In this case report we will describe a lunate avulsion fracture as an isolated injury after a fall from nine meters treated operatively by excision of the comminuted avulsed fragment. After 33 months of follow-up radiographs showed no sign of degenerative joint disorder on simple X-ray, but slight Volar Intercalated Segment Instability (VISI) by a capitolunate angle of 26 degrees was noted. Clinically, the patient was pain free near full wrist and forearm range of motion and could perform his previous vocational and recreational tasks without any limitations. Conclusions Despite apparently good short and mid-term clinical outcome, slight volar intercalated segment instability after 33 months of follow-up revealed that lunotriquetral ligament function was probably lost, which led to static instability. This ligament injury may be missed primarily. Excision of the avulsed osteochondral fragment should be the last option of treatment and most attempts should be tried to fix and/or restore the normal anatomy of ligamentous structure. PMID:27626007

  14. A unique procedure for treatment of osteochondral lesions of the tarsal navicular: three cases in athletes.

    PubMed

    Saxena, Amol; Fullem, Brian W

    2013-01-01

    Surgery in the athlete can present unique challenges, particularly when articular damage and osteoarthritic changes are noted. To allow athletes to return to their desired activity level, an alternative to the traditional approach of fusion must be developed. We prospectively reviewed 3 cases of osteochondral lesions and degenerative changes of the tarsal navicular joint involving a unique surgical approach consisting of microfracture of the lesions with concomitant arthrodiastasis. All 3 patients were treated with a miniexternal fixator to provide distraction for 4 weeks. The patients were aged 15, 17, and 21 years, with follow-up ranging from 2 to 4 years, at which point each patient was competing at their desired activity level and pain free. Each patient was initially treated at different stages of a navicular injury with patient 3 having undergone 2 courses of casted non-weightbearing. This new treatment gives more options to a potentially athletic career-ending injury. Copyright © 2013 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  15. Feasibility of ultrasound imaging of osteochondral defects in the ankle: a clinical pilot study.

    PubMed

    Kok, A C; Terra, M P; Muller, S; Askeland, C; van Dijk, C N; Kerkhoffs, G M M J; Tuijthof, G J M

    2014-10-01

    Talar osteochondral defects (OCDs) are imaged using magnetic resonance imaging (MRI) or computed tomography (CT). For extensive follow-up, ultrasound might be a fast, non-invasive alternative that images both bone and cartilage. In this study the potential of ultrasound, as compared with CT, in the imaging and grading of OCDs is explored. On the basis of prior CT scans, nine ankles of patients without OCDs and nine ankles of patients with anterocentral OCDs were selected and classified using the Loomer CT classification. A blinded expert skeletal radiologist imaged all ankles with ultrasound and recorded the presence of OCDs. Similarly to CT, ultrasound revealed typical morphologic OCD features, for example, cortex irregularities and loose fragments. Cartilage disruptions, Loomer grades IV (displaced fragment) and V (cyst with fibrous roof), were visible as well. This study encourages further research on the use of ultrasound as a follow-up imaging modality for OCDs located anteriorly or centrally on the talar dome. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  16. Joint immobilization inhibits spontaneous hyaline cartilage regeneration induced by a novel double-network gel implantation.

    PubMed

    Arakaki, Kazunobu; Kitamura, Nobuto; Kurokawa, Takayuki; Onodera, Shin; Kanaya, Fuminori; Gong, Jian-Ping; Yasuda, Kazunori

    2011-02-01

    We have recently discovered that spontaneous hyaline cartilage regeneration can be induced in an osteochondral defect in the rabbit, when we implant a novel double-network (DN) gel plug at the bottom of the defect. To clarify whether joint immobilization inhibits the spontaneous hyaline cartilage regeneration, we conducted this study with 20 rabbits. At 4 or 12 weeks after surgery, the defect in the mobile knees was filled with a sufficient volume of the hyaline cartilage tissue rich in proteoglycan and type-2 collagen, while no cartilage tissues were observed in the defect in the immobilized knees. Type-2 collagen, Aggrecan, and SOX9 mRNAs were expressed only in the mobile knees at each period. This study demonstrated that joint immobilization significantly inhibits the spontaneous hyaline cartilage regeneration induced by the DN gel implantation. This fact suggested that the mechanical environment is one of the significant factors to induce this phenomenon.

  17. Bone-Induced Chondroinduction in Sheep Jamshidi Biopsy Defects with and without Treatment by Subchondral Chitosan-Blood Implant

    PubMed Central

    Bell, Angela D.; Lascau-Coman, Viorica; Sun, Jun; Chen, Gaoping; Lowerison, Mark W.; Hurtig, Mark B.

    2013-01-01

    Objective: Delivery of chitosan to subchondral bone is a novel approach for augmented marrow stimulation. We evaluated the effect of 3 presolidified chitosan-blood implant formulations on osteochondral repair progression compared with untreated defects. Design: In N = 5 adult sheep, six 2-mm diameter Jamshidi biopsy holes were created bilaterally in the medial femoral condyle and treated with presolidified chitosan-blood implant with fluorescent chitosan tracer (10 kDa, 40 kDa, or 150k Da chitosan, left knee) or left to bleed (untreated, right knee). Implant residency and osteochondral repair were assessed at 1 day (N = 1), 3 weeks (N = 2), or 3 months (N = 2) postoperative using fluorescence microscopy, histomorphometry, stereology, and micro–computed tomography. Results: Chitosan implants were retained in 89% of treated Jamshidi holes up to 3 weeks postoperative. At 3 weeks, biopsy sites were variably covered by cartilage flow, and most bone holes contained cartilage flow fragments and heterogeneous granulation tissues with sparse leukocytes, stromal cells, and occasional adipocytes (volume density 1% to 3%). After 3 months of repair, most Jamshidi bone holes were deeper, remodeling at the edges, filled with angiogenic granulation tissue, and lined with variably sized chondrogenic foci fused to bone trabeculae or actively repairing bone plate. The 150-kDa chitosan implant elicited more subchondral cartilage formation compared with 40-kDa chitosan-treated and control defects (P < 0.05, N = 4). Treated defects contained more mineralized repair tissue than control defects at 3 months (P < 0.05, N = 12). Conclusion: Bone plate–induced chondroinduction is an articular cartilage repair mechanism. Jamshidi biopsy repair takes longer than 3 months and can be influenced by subchondral chitosan-blood implant. PMID:26069656

  18. Acute hyperextension/valgus trauma to the elbow in top-level adult male water polo goalkeepers: a cause of osteochondritis disecans of the capitellum?

    PubMed

    Rod, Eduard; Ivkovic, Alan; Boric, Igor; Jankovic, Sasa; Radic, Andrej; Hudetz, Damir

    2013-09-01

    We report on 2 cases of hyperextension/valgus elbow injuries in two adult male national team water polo goalkeepers. Both were healthy and had never sustained any major injuries of the elbow. Mechanism and type of injury in both of them was identical. Different medical treatment protocols of these injuries possibly have led to different outcomes, with one of them developing osteochondritis dissecans (OCD). Inadequate medical treatment of acute impact elbow injuries could lead to osteochondritis disecans of the elbow in top-level adult male water polo goalkeepers.

  19. Arthroscopically Assisted Treatment of Navicular Osteochondral Defect Using Flowable Collagen, Iliac Crest Bone Marrow Aspirate and Fibrin Glue: A Case Report.

    PubMed

    Keller, Thomas C; Dempsey, Ian J; Park, Joseph S

    2015-10-01

    A 32-year-old male recreational athlete presented with activity-related chronic dorsal midfoot pain. Conservative treatment, including a prolonged period of immobilization, physical therapy, nonsteroidal anti-inflammatory drugs, and use of a bone stimulator, failed to resolve his symptoms. Computed tomography and magnetic resonance imaging demonstrated a cystic appearing focus within the navicular in conjunction with a osteochondral lesion within the proximal articular surface of the navicular. This case report presents an arthroscopically assisted treatment of a navicular osteochondral lesion using curettage and backfilling with fibrin glue, flowable collagen, and autogenous bone grafting. Therapeutic, Level IV. © 2014 The Author(s).

  20. Enhancement of docosahexaenoic acid production by low-energy ion implantation coupled with screening method based on Sudan black B staining in Schizochytrium sp.

    PubMed

    Fu, Jie; Chen, Tao; Lu, Hao; Lin, Yuanfeng; Xie, Xinlei; Tian, Hua; Zheng, Cao; He, Dongping

    2016-12-01

    Schizochytrium sp. is a hopeful docosahexaenoic acid (DHA) producing candidate due to its rapid growth rate and high DHA proportion in total lipid content. In this study, low-energy ion implantation was applied to Schizochytrium sp. to induce high DHA-producing mutants. Screening these mutants by Sudan black B staining, a mutant strain S1 which showed a 61% improvement in DHA production than that of the parent strain was successfully selected. Subsequently, parameters of DHA production of mutant strain S1 were optimized in a 500-mL Erlenmeyer flask. Under the optimum fermentation conditions, the production of DHA and the percentage of DHA in total lipid of mutant strain S1 were 6.52g/L and 46.2%, respectively. This study provides an effective breeding strategy for improved DHA production of Schizochytrium sp. through combination of the novel mutagenesis technology, the effective screening method and fermentation optimization. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Exploring Effectiveness of Computer-Aided Planning in Implant Positioning for a Single Immediate Implant Placement.

    PubMed

    Edelmann, Alexander R; Hosseini, Bashir; Byrd, Warren C; Preisser, John S; Tyndall, Donald A; Nguyen, Tung; Bencharit, Sompop

    2016-06-01

    The value of computer-aided implant planning using cone-beam computerized tomography (CBCT) for single immediate implants was explored. Eighteen patients requiring extraction of a tooth followed by a single immediate implant were enrolled. Small volume preoperative CBCT scans were used to plan the position of the implant. A taper screwed-type implant was immediately placed into a fresh socket using only the final 1 or 2 drills for osteotomy. Postoperative CBCTs were used for the analysis of actual implant placement positioning. Measurements of the planned and the actual implant position were made with respect to their position relative to the adjacent teeth. Mesio-distal displacements and the facial-lingual deviation of the implant from the planned position were determined. Changes in the angulation of the planned and actual implant position in relation to the clinical crown were also measured. To statistically summarize the results, box plots and 95% CIs for means of paired differences were used. The analysis showed no statistical difference between the planned position and final implant placement position in any measurement. The CBCT scans coupled with the computer-aided implant planning program along with a final 1-to-2 drill protocol may improve the accuracy of single immediate implant placement for taper screwed-type implants.

  2. Reconfigurable Resonant Regulating Rectifier With Primary Equalization for Extended Coupling- and Loading-Range in Bio-Implant Wireless Power Transfer.

    PubMed

    Li, Xing; Meng, Xiaodong; Tsui, Chi-Ying; Ki, Wing-Hung

    2015-12-01

    Wireless power transfer using reconfigurable resonant regulating (R(3)) rectification suffers from limited range in accommodating varying coupling and loading conditions. A primary-assisted regulation principle is proposed to mitigate these limitations, of which the amplitude of the rectifier input voltage on the secondary side is regulated by accordingly adjusting the voltage amplitude Veq on the primary side. A novel current-sensing method and calibration scheme track Veq on the primary side. A ramp generator simultaneously provides three clock signals for different modules. Both the primary equalizer and the R(3) rectifier are implemented as custom integrated circuits fabricated in a 0.35 μm CMOS process, with the global control implemented in FPGA. Measurements show that with the primary equalizer, the workable coupling and loading ranges are extended by 250% at 120 mW load and 300% at 1.2 cm coil distance compared to the same system without the primary equalizer. A maximum rectifier efficiency of 92.5% and a total system efficiency of 62.4% are demonstrated.

  3. A genome-wide association study of osteochondritis dissecans in the Thoroughbred.

    PubMed

    Corbin, Laura J; Blott, Sarah C; Swinburne, June E; Sibbons, Charlene; Fox-Clipsham, Laura Y; Helwegen, Maud; Parkin, Tim D H; Newton, J Richard; Bramlage, Lawrence R; McIlwraith, C Wayne; Bishop, Stephen C; Woolliams, John A; Vaudin, Mark

    2012-04-01

    Osteochondrosis is a developmental orthopaedic disease that occurs in horses, other livestock species, companion animal species, and humans. The principal aim of this study was to identify quantitative trait loci (QTL) associated with osteochondritis dissecans (OCD) in the Thoroughbred using a genome-wide association study. A secondary objective was to test the effect of previously identified QTL in the current population. Over 300 horses, classified as cases or controls according to clinical findings, were genotyped for the Illumina Equine SNP50 BeadChip. An animal model was first implemented in order to adjust each horse's phenotypic status for average relatedness among horses and other potentially confounding factors which were present in the data. The genome-wide association test was then conducted on the residuals from the animal model. A single SNP on chromosome 3 was found to be associated with OCD at a genome-wide level of significance, as determined by permutation. According to the current sequence annotation, the SNP is located in an intergenic region of the genome. The effects of 24 SNPs, representing QTL previously identified in a sample of Hanoverian Warmblood horses, were tested directly in the animal model. When fitted alongside the significant SNP on ECA3, two of these SNPs were found to be associated with OCD. Confirmation of the putative QTL identified on ECA3 requires validation in an independent sample. The results of this study suggest that a significant challenge faced by equine researchers is the generation of sufficiently large data sets to effectively study complex diseases such as osteochondrosis.

  4. Osteochondritis dissecans of the humeral capitellum: reliability of four classification systems using radiographs and computed tomography.

    PubMed

    Claessen, Femke M A P; van den Ende, Kimberly I M; Doornberg, Job N; Guitton, Thierry G; Eygendaal, Denise; van den Bekerom, Michel P J

    2015-10-01

    The radiographic appearance of osteochondritis dissecans (OCD) of the humeral capitellum varies according to the stage of the lesion. It is important to evaluate the stage of OCD lesion carefully to guide treatment. We compared the interobserver reliability of currently used classification systems for OCD of the humeral capitellum to identify the most reliable classification system. Thirty-two musculoskeletal radiologists and orthopaedic surgeons specialized in elbow surgery from several countries evaluated anteroposterior and lateral radiographs and corresponding computed tomography (CT) scans of 22 patients to classify the stage of OCD of the humeral capitellum according to the classification systems developed by (1) Minami, (2) Berndt and Harty, (3) Ferkel and Sgaglione, and (4) Anderson on a Web-based study platform including a Digital Imaging and Communications in Medicine viewer. Magnetic resonance imaging was not evaluated as part of this study. We measured agreement among observers using the Siegel and Castellan multirater κ. All OCD classification systems, except for Berndt and Harty, which had poor agreement among observers (κ = 0.20), had fair interobserver agreement: κ was 0.27 for the Minami, 0.23 for Anderson, and 0.22 for Ferkel and Sgaglione classifications. The Minami Classification was significantly more reliable than the other classifications (P < .001). The Minami Classification was the most reliable for classifying different stages of OCD of the humeral capitellum. However, it is unclear whether radiographic evidence of OCD of the humeral capitellum, as categorized by the Minami Classification, guides treatment in clinical practice as a result of this fair agreement. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  5. Osteochondritis Dissecans of the Humeral Capitellum: The Significance of Lesion Location.

    PubMed

    Kolmodin, Joel; Saluan, Paul

    2014-04-01

    There is a paucity of information regarding the effect of lesion location on surgical outcomes in the treatment of osteochondritis dissecans (OCD) of the humeral capitellum. To survey the literature for conclusions that can be drawn regarding the effect of lesion location on treatment of capitellar OCD lesion. The hypothesis was that lesion severity and the need for more aggressive surgical interventions are increased for lesions that are located laterally on the capitellum. Systematic review; Level of evidence, 4. All studies from the past 20 years were determined using a literature search of PubMed, Scopus, and Cochrane databases. Included studies were clinical studies that specifically commented on the location of the OCD defect on the capitellum. Excluded studies were case reports, review articles, and those that did not include information regarding the location of the OCD lesion on the capitellum. Six studies met the inclusion criteria. Autograft reconstruction was found to yield reliable outcomes regardless of lesion location, as 87% (26/30) of lateral lesions had excellent or good outcomes using the Timmerman and Andrews score, while 91% (21/23) of central lesions had excellent or good outcomes. There was a trend toward improved outcomes with more aggressive surgical management of lateral lesions, specifically those involving the lateral cartilage margin. The failure rate for nonreconstructive operative management for lateral lesions was noted to be significant, as failure rates for peg fixation of lateral lesions was seen to be as high as 44% (4/9) in one of the studies. Studies regarding capitellar OCD lesion location, as it relates to symptom severity and surgical outcome, are limited. The literature suggests that lesions located on the lateral capitellum-particularly those involving the lateral cartilage margin-require more aggressive surgical management than those located medially. A refinement of the Takahara classification is proposed, which includes

  6. Unique Anatomic Feature of the Posterior Cruciate Ligament in Knees Associated With Osteochondritis Dissecans

    PubMed Central

    Ishikawa, Masakazu; Adachi, Nobuo; Yoshikawa, Masahiro; Nakamae, Atsuo; Nakasa, Tomoyuki; Ikuta, Yasunari; Hayashi, Seiju; Deie, Masataka; Ochi, Mitsuo

    2016-01-01

    Background: Osteochondritis dissecans (OCD) of the knee is a disorder in juveniles and young adults; however, its etiology still remains unclear. For OCD at the medial femoral condyle (MFC), it is sometimes observed that the lesion has a connection with fibers of the posterior cruciate ligament (PCL). Although this could be important information related to the etiology of MFC OCD, there is no report examining an association between the MFC OCD and the PCL anatomy. Purpose: To investigate the anatomic features of knees associated with MFC OCD, focusing especially on the femoral attachment of the PCL, and to compare them with knees associated with lateral femoral condyle (LFC) OCD and non-OCD lesions. Study Design: Case-control study; Level of evidence, 3. Methods: We retrospectively reviewed 39 patients (46 knees) with OCD lesions who had undergone surgical treatment. Using magnetic resonance imaging (MRI) scans, the PCL attachment at the lateral wall of the MFC was measured on the coronal sections, and the knee flexion angle was also measured on the sagittal sections. As with non-OCD knees, we reviewed and analyzed 25 knees with anterior cruciate ligament (ACL) injuries and 16 knees with meniscal injuries. Results: MRIs revealed that the femoral PCL footprint was located in a significantly more distal position in the patients with MFC OCD compared with patients with LFC OCD and ACL and meniscal injuries. There was no significant difference in knee flexion angle among the 4 groups. Conclusion: The PCL in patients with MFC OCD attached more distally at the lateral aspect of the MFC compared with knees with LFC OCD and ACL and meniscal injuries. PMID:27294170

  7. Influence of juvenile osteochondral conditions on racing performance in Thoroughbreds born in Normandy.

    PubMed

    Robert, Céline; Valette, Jean-Paul; Jacquet, Sandrine; Denoix, Jean-Marie

    2013-07-01

    The relationship between osteoarticular status and future athletic capacity is commonly accepted in equine practice, but there is little to support this belief in Thoroughbreds. The objective of this study was to assess the prevalence of juvenile osteochondral conditions (JOCC) in Thoroughbred yearlings and to investigate the significance of these with regard to subsequent racing performance. The radiographic files from 328 Thoroughbred yearlings born in Normandy were assessed in a consistent manner and entered into a database together with racing records. Logistic regression models were used to quantify the association between each radiographic parameter and racing performance (raced/not raced, placed/not placed, performer/not performer) at 2, 3, 4 and 5years of age. The front fetlock (30.2% of horses), the dorsal aspect of the hind fetlock (18%), the carpus (15.9%) and the distal part of the hock (15.5%) were the most commonly affected joints. Most horses (87.5%) raced either in turf flat races or in hurdle races. Starting a race at 2years old was more frequent for yearlings without radiographic findings (RF) on the carpus or with less than one RF of moderate severity. The proportions of horses placed at 3years old decreased with increasing number or severity of RF. In racing horses, there was no association between the presence of RF and earnings. The radiographic score, calculated as the sum of all the severity indices found on the radiographic file of the horse appeared well correlated with performance. Using this synthetic index might help veterinarians to evaluate radiographs of Thoroughbred yearlings for potential buyers. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Comparison of radiography and ultrasonography for the diagnosis of osteochondritis dissecans in the equine femoropatellar joint.

    PubMed

    Bourzac, C; Alexander, K; Rossier, Y; Laverty, S

    2009-09-01

    Osteochondritis dissecans (OCD) lesions of the femoropatellar (FP) joint are diagnosed routinely by radiography, but lesions located in the trochlear groove or without accompanying subchondral bone changes can be difficult to visualise. Ultrasonography allows evaluation of articular cartilage and subchondral bone in the FPjoint. To document the radiographic and ultrasonographic appearance of OCD lesions in the equine FP joint, grade ultrasonographic lesions and compare their accuracy in the diagnosis of these lesions. The medical records of all horses diagnosed with FP OCD between 1995 and 2006 were assessed. Inclusion criteria included availability of both radiographic and ultrasonographic images. Lesion characteristics were evaluated in each trochlear ridge and trochlear groove. For assessment of the accuracy (sensitivity and specificity) of both imaging techniques in the diagnosis of OCD, only cases with an arthroscopic or necropsy examination were studied. Twenty-one horses were included. OCD lesions were diagnosed by radiography (30/32 joints) and ultrasound (32/32 joints). The lateral trochlear ridge (LTR, 91%) and the medial trochlear ridge (MTR, 17%) were involved on radiography. The localisation on ultrasound examination was similar (97% LTR, 25% MTR). All but one lesion seen on radiography were also detected with ultrasound; 2 LTR and 3 MTR lesions, not seen on radiography were diagnosed by ultrasound and confirmed at arthroscopy or necropsy. The specificity was 100% regardless of the site and imaging procedure except for the distal third of the MTR (94% for ultrasound). The sensitivity varied, depending on lesion site. Ultrasonography is a valuable diagnostic tool to diagnose OCD lesions in the FP joint and more sensitive than radiography for lesions affecting the MTR of the distal femur. Ultrasound should be considered as a useful adjunct to radiography for diagnosing equine FP OCD, especially in cases of high clinical suspicion but equivocal

  9. Photocrosslinked layered gelatin-chitosan hydrogel with graded compositions for osteochondral defect repair.

    PubMed

    Han, Fengxuan; Yang, Xiaoling; Zhao, Jin; Zhao, Yunhui; Yuan, Xiaoyan

    2015-04-01

    A layered gelatin-chitosan hydrogel with graded composition was prepared via photocrosslinking to simulate the polysaccharide/collagen composition of the natural tissue and mimic the multi-layered gradient structure of the cartilage-bone interface tissue. Firstly, gelatin and carboxymethyl chitosan were reacted with glycidyl methacrylate (GMA) to obtain methacrylated gelatin (Gtn-GMA) and carboxymethyl chitosan (CS-GMA). Then, the mixed solutions of Gtn-GMA in different methacrylation degrees with CS-GMA were prepared to form the superficial, transitional and deep layers of the hydrogel, respectively under the irradiation of ultraviolet light, while polyhedral oligomeric silsesquioxane was introduced in the deep layer to improve the mechanical properties. Results suggested that the pore sizes of the superficial, transitional and deep layers of the layered hydrogel were 115 ± 30, 94 ± 34, 51 ± 12 μm, respectively and their porosities were all higher than 80 %. The compressive strengths of them were 165 ± 54, 565 ± 50 and 993 ± 108 kPa, respectively and the strain of the gradient hydrogel decreased along the thickness direction, similar to the natural tissue. The in vitro cytotoxicity results showed that the hydrogel had good cytocompatibility and the in vivo repair results of osteochondral defect demonstrated remarkable recovery by using the gradient gelatin-chitosan hydrogel, especially when the hydrogel loading transforming growth factor-β1. Therefore, it was suggested that the prepared layered gelatin-chitosan hydrogel in this study could be potentially used to promote cartilage-bone interface tissue repair.

  10. Osteochondral fragmentation of the distal aspect of the patella in horses.

    PubMed

    McIlwraith, C W

    1990-05-01

    A condition characterised by osteochondral fragmentation of the distal aspect of the patella in 15 horses is described. The problem was unilateral in six horses and bilateral in nine. There were eight Quarterhorses, three Thoroughbreds, two American Saddlebreds, one American Paint and one Warmblood-Thoroughbred cross. A previous medial patellar desmotomy had been performed on 12 of the 15 horses. The condition manifested as hindlimb lameness and stiffness ranging from mild to severe. There was fibrous thickening in the stifle area in the 12 cases with a previous medial patellar desmotomy, and synovial effusion in seven of 12 cases. Synovial effusion was present in two of the three cases in which a previous medial patellar desmotomy was not performed. The radiographic changes included bony fragmentation, spurring (with or without an associated subchondral defect), subchondral roughening and subchondral lysis of the distal aspect of the patella. All horses were treated with arthroscopic surgery. The lesions at arthroscopy varied from flaking, fissuring, undermining or fragmentation of the articular cartilage to fragmentation or lysis of the bone at the distal aspect of the patella. The subchondral bone was involved in all cases that had a previous medial patellar desmotomy. Of the 12 horses that had a previous medial patellar desmotomy, eight became sound at their intended use, one was sold in training without problems, one is in early training without problems, one never improved and one is in convalescence. Of the three that did not have a patellar desmotomy, two performed their intended use well but one was unsatisfactory.

  11. Prospective Computed Tomographic Analysis of Osteochondral Lesions of the Ankle Joint Associated With Ankle Fractures.

    PubMed

    Nosewicz, Tomasz L; Beerekamp, M Suzan H; De Muinck Keizer, Robert-Jan O; Schepers, Tim; Maas, Mario; Niek van Dijk, C; Goslings, J Carel

    2016-08-01

    Osteochondral lesions (OCLs) associated with ankle fracture correlate with unfavorable outcome. The goals of this study were to detect OCLs following ankle fracture, to associate fracture type to OCLs and to investigate whether OCLs affect clinical outcome. 100 ankle fractures requiring operative treatment were prospectively included (46 men, 54 women; mean age 44 ± 14 years, range 20-77). All ankle fractures (conventional radiography; 71 Weber B, 22 Weber C, 1 Weber A, 4 isolated medial malleolus and 2 isolated posterior malleolus fractures) were treated by open reduction and internal fixation. Multidetector computed tomography (CT) was performed postoperatively. For each OCL, the location, size, and Loomer OCL classification (CT modified Berndt and Harty classification) were determined. The subjective Foot and Ankle Outcome Scoring (FAOS) was used for clinical outcome at 1 year. OCLs were found in 10/100 ankle fractures (10.0%). All OCLs were solitary talar lesions. Four OCLs were located posteromedial, 4 posterolateral, 1 anterolateral, and 1 anteromedial. There were 2 type I OCLs (subchondral compression), 6 type II OCLs (partial, nondisplaced fracture) and 2 type IV OCLs (displaced fracture). Mean OCL size (largest diameter) was 4.4 ± 1.7 mm (range, 1.7 mm to 6.2 mm). Chi-square analysis showed no significant association between ankle fracture type and occurrence of OCLs. OCLs did occur only in Lauge-Hansen stage III/IV ankle fractures. There were no significant differences in FAOS outcome between patients with or without OCLs. Ten percent of investigated ankle fractures had associated OCLs on CT. Although no significant association between fracture type and OCL was found, OCLs only occurred in Lauge-Hansen stage III/IV ankle fractures. With the numbers available, OCLs did not significantly affect clinical outcome at 1 year according to FAOS. Level IV, observational study. © The Author(s) 2016.

  12. Cartilage repair of experimentally 11 induced osteochondral defects in New Zealand White rabbits.

    PubMed

    Aulin, C; Jensen-Waern, M; Ekman, S; Hägglund, M; Engstrand, T; Hilborn, J; Hedenqvist, P

    2013-01-01

    Articular cartilage has a limited capacity for self-repair in adult humans, and methods used to stimulate regeneration often result in re-growth of fibrous cartilage, which has lower durability. No current treatment option can provide complete repair. The possibility of growth factor delivery into the joint for cartilage regeneration after injury would be an attractive treatment option. A full thickness osteochondral defect of 4 mm in diameter and 2 mm deep was created by mechanical drilling in the medial femoral condyle in 20 female adult New Zealand White rabbits. In an attempt to improve regeneration a hyaluronic hydrogel system, with or without bone morphogenetic protein-2 (BMP-2) was delivered intraarticularly. The contralateral joint defect was treated with saline as control. Throughout the study, rabbits were clinically examined and after 12 (n = 6) or 24 (n = 9) weeks, the rabbits were euthanized and the joints evaluated by histology. The defects healed with fibrocartilage like tissue, and the filling of the defects ranged from less than 25% to complete. The healing of the defects varied both inter- and intra-group wise. Treatment with hyaluronan gel with or without BMP-2 had no effect on cartilage regeneration compared with controls. Instead, severe ectopic bone formation was found in seven joints treated with BMP-2. In conclusion, the present study shows that neither treatment with hyaluronic gel alone, nor in combination with BMP-2, improves the healing of an induced cartilage defect in rabbits. It further shows that BMP-2 can induce ectopic bone formation, which severely affects the functionality of the joint.

  13. Treatment of osteochondral lesions of the talus in athletes: what is the evidence?

    PubMed Central

    VANNINI, FRANCESCA; COSTA, GIUSEPPE GIANLUCA; CARAVELLI, SILVIO; PAGLIAZZI, GHERARDO; MOSCA, MASSIMILIANO

    2016-01-01

    Purpose ankle injuries make up 15% of all sports injuries and osteochondral lesions of the talus (OLTs) are an increasingly frequent problem in active patients. There exist no widely shared guidelines on OLT treatment in the athletic population. The aim of this paper is to review all the existing literature evidence on the surgical treatment of OLTs in athletes, in order to determine the current state of the art in this specific population, underlining both the limits and the potential of the strategies used. Methods a systematic review of the literature was performed focusing on the different types of surgical treatment used for OLTs in athletes. The screening process and analysis were performed separately by two independent researchers. The inclusion criteria for relevant articles were: clinical reports of any level of evidence, written in English, with no time limitation, or clinical reports describing the treatment of OLTs in the athletic population. Results with the consensus of the two observers, relevant data were then extracted and collected in a single database to be analyzed for the purposes of the present manuscript. At the end of the process, 16 papers met the selection criteria. These papers report a total of 642 athletic patients with OCTs. Conclusions the ideal treatment for cartilage lesions in athletes is a controversial topic, due to the need for an early return to sports, especially in elite players; this need leads to extensive use of microfractures in this population, despite the poor quality of repair associated with this technique. None of the surgical strategies described in this paper seems to be superior to the others. Level of evidence systematic review of level IV studies, level IV. PMID:27602351

  14. Prevalence of Osteochondritis Dissecans of the Capitellum in Young Baseball Players: Results Based on Ultrasonographic Findings.

    PubMed

    Matsuura, Tetsuya; Suzue, Naoto; Iwame, Toshiyuki; Nishio, Susumu; Sairyo, Koichi

    2014-08-01

    Osteochondritis dissecans (OCD) of the capitellum is a well-recognized cause of elbow pain and disability in adolescent athletes. However, little is known about the prevalence of OCD in adolescent baseball players. To determine the prevalence of OCD in baseball players aged 10 to 12 years based on ultrasonographic findings and to investigate the clinical characteristics of those with OCD lesions. Descriptive epidemiology study. A total of 1040 players aged 10 to 12 years completed a questionnaire, ultrasound imaging, and radiographic examination to investigate OCD. Sonographic findings were classified into 5 grades (0, 1a, 1b, 2, and 3). Subjects with grade 1a, 1b, 2, or 3 were considered to have abnormal findings of the capitellum and were advised to undergo radiography. Radiographic and ultrasonographic findings were then compared. The prevalence of OCD was calculated, and differences by age and player position were determined. Of the 1040 players, 33 (3.2%) had an abnormal finding on initial ultrasonography screening, and all 33 agreed to undergo radiography. Of them, 22 (66.7%) were found to have OCD of the capitellum on radiographs, giving an overall prevalence of 2.1%. Seven subjects (31.8%) had no history of elbow pain. Based on the radiographic classification, 20 subjects (90.9%) had stage I lesions. Analysis of OCD by age and player position revealed no significant differences. The prevalence of OCD of the capitellum was 2.1% in 1000 baseball players aged 10 to 12 years, with no differences in prevalence according to age or player position.

  15. Bone shape difference between control and osteochondral defect groups of the ankle joint.

    PubMed

    Tümer, N; Blankevoort, L; van de Giessen, M; Terra, M P; de Jong, P A; Weinans, H; Tuijthof, G J M; Zadpoor, A A

    2016-12-01

    The etiology of osteochondral defects (OCDs), for which the ankle (talocrural) joint is one of the common sites, is not yet fully understood. In this study, we hypothesized that bone shape plays a role in development of OCDs. Therefore, we quantitatively compared the morphology of the talus and the distal tibia between an OCD group and a control group. The shape variations of the talus and distal tibia were described separately by constructing two statistical shape models (SSMs) based on the segmentation of the bones from ankle computed tomography (CT) scans obtained from control (i.e., 35 CT scans) and OCD (i.e., 37 CT scans) groups. The first five modes of shape variation for the SSM corresponding to each bone were statistically compared between control and OCD groups using an analysis of variance (ANOVA) corrected with the Bonferroni for multiple comparisons. The first five modes of variation in the SSMs respectively represented 49% and 40% of the total variance of talus and tibia. Less than 5% of the variance per mode was described by the higher modes. Mode 5 of the talus (P = 0.004) primarily describing changes in the vertical neck angle and Mode 1 of the tibia (P < 0.0001) representing variations at the medial malleolus, showed statistically significant difference between the control and OCD groups. Shape differences exist between control and OCD groups. This indicates that a geometry modulated biomechanical behavior of the talocrural joint may be a risk factor for OCD. Copyright © 2016. Published by Elsevier Ltd.

  16. Cochlear Implants

    MedlinePlus

    ... outside of the body, behind the ear. A second part is surgically placed under the skin. An implant does not restore normal hearing. It can help a person understand speech. Children and adults can benefit from them. National Institute on Deafness and Other Communication Disorders

  17. Osteochondral lesions of the capitellum do not affect elbow kinematics and stability with intact collateral ligaments: an in vitro biomechanical study.

    PubMed

    Sabo, Marlis T; McDonald, Colin P; Ferreira, Louis M; Johnson, Jim A; King, Graham J

    2011-01-01

    Osteochondritis dissecans (OCD) of the capitellum most commonly affects adolescent pitchers and gymnasts, who present with pain and mechanical symptoms. Patients with larger lesions have poorer outcomes, possibly related to increased contact pressures on the surrounding articular surface with or without instability. The purpose of this in vitro study was to determine whether displaced OCD lesions of the capitellum lead to altered kinematics and stability of the elbow. We mounted 9 fresh-frozen cadaveric arms in an upper extremity joint testing system, with cables attaching the tendons of the major muscles to motors and pneumatic actuators. An electromagnetic receiver on the ulna enabled quantification of the kinematics of the radius and ulna with respect to the humerus. We used 3-dimensional computed tomography scans and computer-assisted techniques to navigate sequential osteochondral defects ranging in size from 12.5% to 100% of the capitellum. The arms were subjected to active and passive flexion in both the vertical and valgus positions with the forearm in both pronation and supination. We found no significant differences in valgus angulation or ulnar rotation between any of the OCD lesions and the intact elbow during flexion, regardless of arm position or forearm rotation. Osteochondritis dissecans lesions of the capitellum, both small and large, did not alter the ulnohumeral kinematics and stability with intact collateral ligaments. Therefore, excision of unfixable osteochondral fragments of the capitellum in the setting of intact collateral ligaments can be considered without the risk of creating instability. Copyright © 2011. Published by Elsevier Inc.

  18. Composite scaffolds for osteochondral repair obtained by combination of additive manufacturing, leaching processes and hMSC-CM functionalization.

    PubMed

    Díaz Lantada, Andrés; Alarcón Iniesta, Hernán; García-Ruíz, Josefa Predestinación

    2016-02-01

    Articular repair is a relevant and challenging area for the emerging fields of tissue engineering and biofabrication. The need of significant gradients of properties, for the promotion of osteochondral repair, has led to the development of several families of composite biomaterials and scaffolds, using different effective approaches, although a perfect solution has not yet been found. In this study we present the design, modeling, rapid manufacturing and in vitro testing of a composite scaffold aimed at osteochondral repair. The presented composite scaffold stands out for having a functional gradient of density and stiffness in the bony phase, obtained in titanium by means of computer-aided design combined with additive manufacture using selective laser sintering. The chondral phase is obtained by sugar leaching, using a PDMS matrix and sugar as porogen, and is joined to the bony phase during the polymerization of PDMS, therefore avoiding the use of supporting adhesives or additional intermediate layers. The mechanical performance of the construct is biomimetic and the stiffness values of the bony and chondral phases can be tuned to the desired applications, by means of controlled modifications of different parameters. A human mesenchymal stem cell (h-MSC) conditioned medium (CM) is used for improving scaffold response. Cell culture results provide relevant information regarding the viability of the composite scaffolds used. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. The effects of early or late treatment of osteochondral defects on joint homoeostasis: an experimental study in rabbits.

    PubMed

    Ozsoy, Mehmet Hakan; Aydogdu, Semih; Taskiran, Dilek; Sezak, Murat; Hayran, Mutlu; Oztop, Fikri; Ozsoy, Arzu

    2009-06-01

    A 3.5 x 4 mm tubular osteochondral defect was created on the right medial femoral condyles of 51 adult rabbits. In the control group (CG), defects were left untreated. In the early-(ETG) and late-(LTG) treatment groups, defects were treated by an osteoperiosteal graft 1 and 12 weeks, respectively, after the index procedure. Synovial fluid (SF) samples were collected regularly and proteoglycan fragments (PF), total collagen (TC) and collagenase (MMP-1) levels were measured. Rabbits were killed at 4 (early period), 12 (intermediate period), or 24 (late period) weeks postoperatively. Histological examination indicated a more successful healing in both grafting groups than in the CG, but without any difference at any time period between the grafting groups. In the CG, PF, and TC levels in SF increased continuously until the late period, indicating an ongoing degenerative activity in the joints. In contrast, SF marker levels in both grafting groups indicated that normalization in joint metabolism could be achieved-at least partially-after treatment. However, PF levels in the SF showed that the treatment of defects in earlier stages might result in better outcomes since the negative effects were more prominent in chronic stages, presumably due to the more prolonged period of disturbed homeostasis. Thus, histological values and SF marker levels indicated that treatment of osteochondral defects at any time of the disease had a positive effect on healing when compared to no treatment. Early treatment might better assist the recovery of joint homeostasis than late treatment.

  20. AG-041R, a cholecystokinin-B/gastrin receptor antagonist, stimulates the repair of osteochondral defect in rabbit model.

    PubMed

    Nakanishi, Toru; Kawasaki, Kenzo; Uchio, Yuji; Kataoka, Hiroko; Terashima, Masaharu; Ochi, Mitsuo

    2002-03-29

    A newly synthesized compound (AG-041R), 3R-1-(2,2Diethoxyethyl)-((4methylphenyl) amino-carbonyl methyl)-3-((4methylphenyl) ureido-indoline-2-one), is a cholecystokinin-B/gastrin receptor antagonist which has stimulatory effects on the matrix synthesis of chondrocytes in vitro. In this study, we examined the effect of AG-041R on the repair of osteochondral defects (cylindrical, 4 mm diameter) in the patellar groove of the rabbit knee joint. At the time of operation, 100 microl of 1 microM of AG-041R was administered, followed by 200 microl with an osmotic pump for 14 days. Histological and biochemical evaluations were performed at 12 and 24 weeks after surgery. The histological score of the AG-041R-treated group, the quantity of glycosaminoglycan and the ratio of chondroitin sulfate in the AG-041R-treated tissue were significantly higher than in the untreated group. Moreover, the degeneration of cartilage around the defect was suppressed in the AG-041R-treated group. These findings suggest that AG-041R is effective for the repair of osteochondral defects.

  1. Expression of colony-stimulating factor 1 is associated with occurrence of osteochondral change in pigmented villonodular synovitis.

    PubMed

    Ota, Takehiro; Urakawa, Hiroshi; Kozawa, Eiji; Ikuta, Kunihiro; Hamada, Shunsuke; Tsukushi, Satoshi; Shimoyama, Yoshie; Ishiguro, Naoki; Nishida, Yoshihiro

    2015-07-01

    Pigmented villonodular synovitis (PVNS) is a benign, translocation-derived neoplasm. Because of its high local recurrence rate after surgery and occurrence of osteochondral destruction, a novel therapeutic target is required. The present study aimed to evaluate the significance of protein expression possibly associated with the pathogenesis during the clinical course of PVNS. In 40 cases of PVNS, positivity of colony-stimulated factor 1 (CSF1), its receptor (CSF1R), and receptor activator of nuclear factor kappa-B ligand (RANKL) were immunohistochemically determined. The relationship between the positivity and clinical outcomes was investigated. High positivity of CSF1 staining intensity was associated with an increased incidence of osteochondral lesions (bone erosion and osteoarthritis) (p = 0.009), but not with the rate of local recurrence. Positivity of CSF1R and RANKL staining was not associated with any clinical variables. The number of giant cells was not correlated with positivity of any of the three proteins, or with the clinical outcome. Focusing on knee cases, CSF1 positivity was also associated with the incidence of osteochondal change (p = 0.02). CSF1R positivity was high in cases which had local recurrence, but not significantly so (p = 0.129). Determination of CSF1 and CSF1R expression may be useful as a prognosticator of the clinical course and/or outcomes of PVNS.

  2. All-Arthroscopic Autologous Matrix-Induced Chondrogenesis for the Treatment of Osteochondral Lesions of the Talus.

    PubMed

    Usuelli, Federico Giuseppe; de Girolamo, Laura; Grassi, Miriam; D'Ambrosi, Riccardo; Montrasio, Umberto Alfieri; Boga, Michele

    2015-06-01

    Several surgical techniques have been described for the treatment of talar chondral lesions. Among them, microfracture is well established. Autologous matrix-induced chondrogenesis (AMIC), using microfracture and biomaterials, has shown promising results for the treatment of knee osteochondral lesions and has been proposed for the ankle as an open technique. We describe an all-arthroscopic AMIC technique. The benefits of an all-arthroscopic procedure include smaller incisions with less soft-tissue dissection, better visualization of the joint, and a quicker recovery compared with open surgery. The use of matrix to support cartilage regeneration promotes good-quality cartilage tissue with satisfactory long-term outcomes. Our all-arthroscopic AMIC technique uses a type I-type III porcine collagen matrix (Chondro-Gide; Geistlich Pharma, Wolhusen, Switzerland) and is characterized by 2 different arthroscopic surgical phases. First, adequate exposure is achieved through use of a Hintermann spreader (Integra LifeSciences, Plainsboro, NJ) with sufficient joint distraction and wet lesion preparation. The second surgical step is performed dry, involving matrix placement and fixation. The all-arthroscopic AMIC technique for the treatment of osteochondral lesions of the talus allows a very precise reconstruction in the case of cartilage defects and avoids the need for a more invasive operation associated with higher morbidity and a longer surgical time.

  3. All-Arthroscopic Autologous Matrix-Induced Chondrogenesis for the Treatment of Osteochondral Lesions of the Talus

    PubMed Central

    Usuelli, Federico Giuseppe; de Girolamo, Laura; Grassi, Miriam; D'Ambrosi, Riccardo; Montrasio, Umberto Alfieri; Boga, Michele

    2015-01-01

    Several surgical techniques have been described for the treatment of talar chondral lesions. Among them, microfracture is well established. Autologous matrix-induced chondrogenesis (AMIC), using microfracture and biomaterials, has shown promising results for the treatment of knee osteochondral lesions and has been proposed for the ankle as an open technique. We describe an all-arthroscopic AMIC technique. The benefits of an all-arthroscopic procedure include smaller incisions with less soft-tissue dissection, better visualization of the joint, and a quicker recovery compared with open surgery. The use of matrix to support cartilage regeneration promotes good-quality cartilage tissue with satisfactory long-term outcomes. Our all-arthroscopic AMIC technique uses a type I–type III porcine collagen matrix (Chondro-Gide; Geistlich Pharma, Wolhusen, Switzerland) and is characterized by 2 different arthroscopic surgical phases. First, adequate exposure is achieved through use of a Hintermann spreader (Integra LifeSciences, Plainsboro, NJ) with sufficient joint distraction and wet lesion preparation. The second surgical step is performed dry, involving matrix placement and fixation. The all-arthroscopic AMIC technique for the treatment of osteochondral lesions of the talus allows a very precise reconstruction in the case of cartilage defects and avoids the need for a more invasive operation associated with higher morbidity and a longer surgical time. PMID:26258040

  4. Combined autologous chondrocyte implantation (ACI) with supra-condylar femoral varus osteotomy, following lateral growth-plate damage in an adolescent knee: 8-year follow-up

    PubMed Central

    2011-01-01

    We report the 8-year clinical and radiographic outcome of an adolescent patient with a large osteochondral defect of the lateral femoral condyle, and ipsilateral genu valgum secondary to an epiphyseal injury, managed with autologous chondrocyte implantation (ACI) and supracondylar re-alignment femoral osteotomy. Long-term clinical success was achieved using this method, illustrating the effective use of re-alignment osteotomy in correcting mal-alignment of the knee, protecting the ACI graft site and providing the optimum environment for cartilage repair and regeneration. This is the first report of the combined use of ACI and femoral osteotomy for such a case. PMID:21418566

  5. Combined autologous chondrocyte implantation (ACI) with supra-condylar femoral varus osteotomy, following lateral growth-plate damage in an adolescent knee: 8-year follow-up.

    PubMed

    Vijayan, Sridhar; Bentley, George

    2011-03-18

    We report the 8-year clinical and radiographic outcome of an adolescent patient with a large osteochondral defect of the lateral femoral condyle, and ipsilateral genu valgum secondary to an epiphyseal injury, managed with autologous chondrocyte implantation (ACI) and supracondylar re-alignment femoral osteotomy. Long-term clinical success was achieved using this method, illustrating the effective use of re-alignment osteotomy in correcting mal-alignment of the knee, protecting the ACI graft site and providing the optimum environment for cartilage repair and regeneration. This is the first report of the combined use of ACI and femoral osteotomy for such a case.

  6. Biodegradable implants in traumatology: a review on the state-of-the-art.

    PubMed

    Hofmann, G O

    1995-01-01

    Up to now the internal fixation of fractured bones and joints has been managed by metal implants. There are certain associated disadvantages: the mechanical properties of the metals are stronger than those of cortical bone ("stress-protection"); the removal of the implants requires a second operation; an increasing number of patients are confronted with problems of sensitivity to metal components of the implants, especially nickel. About 40 different biodegradable polymers, copolymers and composites have been developed as substitutes for metal implants in internal fracture fixation. The early experimental and clinical results demonstrate their limitations. From the current point of view, it is not possible to transfer the designs and assembling principles of metal implants in orthopaedic surgery to biodegradable polymers. The attempt to simply mimic metal implants in polymers is condemned to fail from the very beginning. This is a review of the literature and of our first 100 patients operated on using implants made of self-reinforced polyglycolide acid and polydioxanone. The main difficulty with the material is the loss of stiffness in a time interval which is not long enough to guarantee bone healing. The development of a sterile sinus over the site of implantation is a problem also reported by other groups. Certain additives have to be inserted into the polymers to make them visible on conventional X-radiographs. Despite these drawbacks, however, there are indications for the isolated or adjuvant implantation of biodegradable materials. They could be employed in the treatment of osteochondral fractures and other defined injuries. The available literature on these indications will be discussed.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. The use of autologous chondrocyte implantation following and combined with anterior cruciate ligament reconstruction

    PubMed Central

    Bartlett, W.; Gooding, C. R.; Sood, M.; Skinner, J. A.; Carrington, R. W.J.; Briggs, T. W.R.; Bentley, G.

    2005-01-01

    We report our experience of using autologous chondrocyte implantation (ACI) to treat osteochondral defects of the knee in combination with anterior cruciate ligament (ACL) reconstruction. The outcome of symptomatic osteochondral lesions treated with ACI following previous successful ACL reconstruction is also reviewed. Patients were followed for a mean of 23 months. Nine patients underwent ACL reconstruction in combination with ACI. Mean modified Cincinnati knee scores improved from 42 to 69 following surgery. Seven patients described their knee as better and two as the same. A second group of nine patients underwent ACI for symptomatic articular cartilage defects following previous ACL reconstruction. In this group, the mean modified Cincinnati knee score improved from 53 to 62 after surgery. Six patients described their knee as better and three as worse. Combined treatment using ACI with ACL reconstruction is technically feasible and resulted in sustained improvement in pain and function. The results following previous ACL reconstruction also resulted in clinical improvement, although results were not as good as following the combined procedure. PMID:16320051

  8. Outcome of combined autologous chondrocyte implantation and anterior cruciate ligament reconstruction.

    PubMed

    Dhinsa, Baljinder S; Nawaz, Syed Z; Gallagher, Kieran R; Skinner, John; Briggs, Tim; Bentley, George

    2015-01-01

    Instability of the knee joint, after anterior cruciate ligament (ACL) injury, is contraindication to osteochondral defect repair. This prospective study is to investigate the role of combined autologous chondrocyte implantation (ACI) with ACL reconstruction. Three independent groups of patients with previous ACL injuries undergoing ACI were identified and prospectively followed up. The first group had ACI in combination with ACL reconstruction (combined group); the 2(nd) group consisted of individuals who had an ACI procedure having had a previously successful ACL reconstruction (ACL first group); and the third group included patients who had an ACI procedure to a clinically stable knee with documented nonreconstructed ACL disruption (No ACL group). Their outcomes were assessed using the modified cincinnati rating system, the Bentley functional (BF) rating system (BF) and a visual analog scale (VAS). At a mean followup of 64.24 months for the ACL first group, 63 months for combined group and 78.33 months for the No ACL group; 60% of ACL first patients, 72.73% of combined group and 83.33% of the No ACL group felt their outcome was better following surgery. There was no significant difference demonstrated in BF and VAS between the combined and ACL first groups. Results revealed a significant affect of osteochondral defect size on outcome measures. The study confirms that ACI in combination with ACL reconstruction is a viable option with similar outcomes as those patients who have had the procedures staged.

  9. Associations of horse age, joint type, and osteochondral injury with serum and synovial fluid concentrations of type II collagen biomarkers in Thoroughbreds.

    PubMed

    Nicholson, Anne M; Trumble, Troy N; Merritt, Kelly A; Brown, Murray P

    2010-07-01

    To determine the effects of horse age, osteochondral injury, and joint type on a synthesis biomarker and 3 degradative biomarkers of type II collagen in Thoroughbreds. Healthy rested adult (3- to 12-year-old) Thoroughbreds (n = 19), yearling (1- to 2-year-old) Thoroughbreds (40), and Thoroughbred racehorses (2 to 7 years old) undergoing arthroscopic surgery for removal of osteochondral fragments that resulted from training or racing (41). Samples of blood and metacarpophalangeal, metatarsophalangeal, or carpal joint synovial fluid (SF) were collected from all horses. Commercially available assays were used to analyze SF and serum concentrations of type II collagen biomarkers of synthesis (carboxy propeptide of type II collagen [CPII]) and degradation (cross-linked C-telopeptide fragments of type II collagen [CTX II], neoepitope generated by collagenase cleavage of type I and II collagen [C1,2C], and neoepitope generated by collagenase cleavage of type II collagen [C2C]). Osteochondral injury affected concentrations of CPII, CTX II, C1,2C, and C2C in SF, serum, or both, compared with concentrations in healthy adult horses. Compared with adult horses, yearling horses had increased SF or serum concentrations of degradative biomarkers (CTX II, C1,2C, and C2C). Concentrations were higher in carpal than metacarpophalangeal or metatarsophalangeal joints for all biomarkers in osteochondral-injured horses. Variable differences in SF concentrations between joint types were detected in healthy adult and yearling horses. Horse age, osteochondral injury, and joint type all significantly affected type II collagen biomarker concentrations in SF and serum of Thoroughbreds.

  10. Subchondral bone cysts, osteochondritis dissecans, and Legg-Calvé-Perthes disease: a correlation and proposal of their possible common etiology and pathogenesis.

    PubMed

    Levine, B; Kanat, I O

    1988-01-01

    Various theoretical hypotheses have been proposed for the nontraumatic etiology of osteochondritis dissecans, subchondral bone cyst formation, and Legg-Calvé-Perthes disease. Although a direct relationship between these distinct clinical entities has sparse referral in the literature, their common theories of etiology and evolution have been extensively documented, although not correlated. The various etiologic theories of osteochondritis dissecans, Legg-Calvé-Perthes disease, and subchondral bone cyst formation have been individually presented. The conclusion drawn upon review of these theories would prove that all of the proposed etiologies for the above syndromes are remarkably similar. Furthermore, as referred to in the contents of this paper, the signs, symptoms, and roentgenographic findings also appear to be common to all three syndromes. Various clinicopathologic studies have demonstrated similar gross pathologic and histologic findings between osteochondritis dissecans, subchondral bone cysts formation, and Legg-Calvé-Perthes disease. The authors, therefore, contend that the most likely nontraumatic etiology of this condition is a common multifactorial causation with an identical pathogenesis. They propose a common etiology resulting in a pathologic process, originating in subchondral cyst formation. Eventually, a communication between the cysts and the joint will occur secondary to either the duration and progression of the cystic process, endogenous, or exogenous stress resulting in collapse of the articular surface. A complete or partially detached osteochondral fragment results from these forces. Osteochondritis dissecans and Legg-Calvé-Perthes disease may represent the same stage in the pathologic process. Degenerative joint disease is the final stage of this pathologic process. Further studies need to be performed to explore this relationship and the proposed pathogenesis.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Axial load-bearing capacity of an osteochondral autograft stabilized with a resorbable osteoconductive bone cement compared with a press-fit graft in a bovine model.

    PubMed

    Kiss, Marc-Olivier; Levasseur, Annie; Petit, Yvan; Lavigne, Patrick

    2012-05-01

    Osteochondral autografts in mosaicplasty are inserted in a press-fit fashion, and hence, patients are kept nonweightbearing for up to 2 months after surgery to allow bone healing and prevent complications. Very little has been published regarding alternative fixation techniques of those grafts. Osteochondral autografts stabilized with a resorbable osteoconductive bone cement would have a greater load-bearing capacity than standard press-fit grafts. Controlled laboratory study. Biomechanical testing was conducted on 8 pairs of cadaveric bovine distal femurs. For the first 4 pairs, 6 single osteochondral autografts were inserted in a press-fit fashion on one femur. On the contralateral femur, 6 grafts were stabilized with a calcium triglyceride osteoconductive bone cement. For the 4 remaining pairs of femurs, 4 groups of 3 adjacent press-fit grafts were inserted on one femur, whereas on the contralateral femur, grafts were cemented. After a maturation period of 48 hours, axial loading was applied on all single grafts and on the middle graft of each 3-in-a-row series. For the single-graft configuration, median loads required to sink the press-fit and cemented grafts by 2 and 3 mm were 281.87 N versus 345.56 N (P = .015) and 336.29 N versus 454.08 N (P = .018), respectively. For the 3-in-a-row configuration, median loads required to sink the press-fit and cemented grafts by 2 and 3 mm were 260.31 N versus 353.47 N (P = .035) and 384.83 N versus 455.68 N (P = .029), respectively. Fixation of osteochondral grafts using bone cement appears to improve immediate stability over the original mosaicplasty technique for both single- and multiple-graft configurations. Achieving greater primary stability of osteochondral grafts could potentially accelerate postoperative recovery, allowing early weightbearing and physical therapy.

  12. Short Implants: New Horizon in Implant Dentistry

    PubMed Central

    Gulati, Manisha; Garg, Meenu; Pathak, Chetan

    2016-01-01

    The choice of implant length is an essential factor in deciding the survival rates of these implants and the overall success of the prosthesis. Placing an implant in the posterior part of the maxilla and mandible has always been very critical due to poor bone quality and quantity. Long implants can be placed in association with complex surgical procedures such as sinus lift and bone augmentation. These techniques are associated with higher cost, increased treatment time and greater morbidity. Hence, there is need for a less invasive treatment option in areas of poor bone quantity and quality. Data related to survival rates of short implants, their design and prosthetic considerations has been compiled and structured in this manuscript with emphasis on the indications, advantages of short implants and critical biomechanical factors to be taken into consideration when choosing to place them. Studies have shown that comparable success rates can be achieved with short implants as those with long implants by decreasing the lateral forces to the prosthesis, eliminating cantilevers, increasing implant surface area and improving implant to abutment connection. Short implants can be considered as an effective treatment alternative in resorbed ridges. Short implants can be considered as a viable treatment option in atrophic ridge cases in order to avoid complex surgical procedures required to place long implants. With improvement in the implant surface geometry and surface texture, there is an increase in the bone implant contact area which provides a good primary stability during osseo-integration. PMID:27790598

  13. Short Implants: New Horizon in Implant Dentistry.

    PubMed

    Jain, Neha; Gulati, Manisha; Garg, Meenu; Pathak, Chetan

    2016-09-01

    The choice of implant length is an essential factor in deciding the survival rates of these implants and the overall success of the prosthesis. Placing an implant in the posterior part of the maxilla and mandible has always been very critical due to poor bone quality and quantity. Long implants can be placed in association with complex surgical procedures such as sinus lift and bone augmentation. These techniques are associated with higher cost, increased treatment time and greater morbidity. Hence, there is need for a less invasive treatment option in areas of poor bone quantity and quality. Data related to survival rates of short implants, their design and prosthetic considerations has been compiled and structured in this manuscript with emphasis on the indications, advantages of short implants and critical biomechanical factors to be taken into consideration when choosing to place them. Studies have shown that comparable success rates can be achieved with short implants as those with long implants by decreasing the lateral forces to the prosthesis, eliminating cantilevers, increasing implant surface area and improving implant to abutment connection. Short implants can be considered as an effective treatment alternative in resorbed ridges. Short implants can be considered as a viable treatment option in atrophic ridge cases in order to avoid complex surgical procedures required to place long implants. With improvement in the implant surface geometry and surface texture, there is an increase in the bone implant contact area which provides a good primary stability during osseo-integration.

  14. Results of Surgical Management of Osteochondritis Dissecans of the Ankle in the Pediatric and Adolescent Population.

    PubMed

    Kramer, Dennis E; Glotzbecker, Michael P; Shore, Benjamin J; Zurakowski, David; Yen, Yi-Meng; Kocher, Mininder S; Micheli, Lyle J

    2015-01-01

    There is a paucity of published literature on operative management of osteochondritis dissecans (OCD) in the ankle in adolescents. This study seeks to elucidate patient and lesion characteristics associated with surgical success and failure as well as reporting functional outcomes. Retrospective chart review identified all patients aged 18 years old or younger surgically treated for OCD of the ankle at our institution from 2001 to 2010. This included 109 ankles in 100 patients (75 female, 25 male), mean age 14.3 ± 2.3 years (range, 7 to 18 y), with a median follow-up of 3.3 years (range, 1 to 10.8 y). Patient and lesion data, surgical procedure, clinical results, and complications were recorded. Postoperative radiographs were reviewed in 80 ankles. A return to sport survey and a Foot and Ankle Outcome Score (FAOS) was sent to all patients. Multivariate statistical analysis evaluated predictors of reoperation rate, Berndt and Harty clinical grade, and FAOS scores. Kaplan-Meier analysis was applied to determine freedom from reoperation. The OCD lesion was most commonly found on the medial talus (80, 73%). The most common procedures performed included transarticular drilling (59, 54%), fixation (22, 20%), and excision microfracture (27, 26%). The overall rate of reoperation was 27% (29/109). Berndt and Harty clinical grade was poor (33, 30%), fair (23, 21%), and good (53, 49%). Reoperation rates were significantly higher for OCD lesions in which postoperative radiographs had no change or looked worse (10/16, 63%) (P = 0.002). Thirty-six of 44 survey respondents (82%) were satisfied and 37 (84%) returned to sports at a median time of 6 months. Average FAOS score was 77 ± 18. Multiple linear regression confirmed that female sex and elevated body mass index were significant negative predictors for FAOS score. The reoperation rate following surgical intervention for OCD of the ankle is high. Females and those with a higher body mass index may have worse subjective

  15. Quantification Analysis of the Intraoperative Bacterial Contamination Rate and Level in Osteochondral Autografts.

    PubMed

    Alomar, Abdulaziz Z; Somily, Ali Mohammed; Alraiyes, Thamer M; Bin Nasser, Ahmad S; Aljassir, Fawzi F

    2016-03-01

    Inadvertent contamination of osteochondral (OC) autografts during harvesting and preparation can lead to significant complications and can cause the operating team to weigh the infection risk after reimplantation against discarding the OC fragment. The most commonly reported contamination mechanism is the accidental dropping of an OC fragment; however, associated contamination levels remain unclear. The rate and level of contamination during standard harvesting and preparation are also unknown. To quantitatively evaluate the rate and level of bacterial contamination of OC autografts during harvesting and preparation compared with those of accidently dropped autografts. Controlled laboratory study. Under sterile conditions, 138 fresh OC specimens were harvested and retrieved from 23 primary total knee arthroplasties (TKAs). Six OC fragments were retrieved from each TKA: 3 were used as controls, and 3 were dropped onto the operating room floor. Each specimen was incubated to allow for aerobic and anaerobic growth, and the number of colony-forming units (CFUs) per gram was calculated. Contamination rates (positive cultures) for the control and dropped groups were 29% (n = 20/69) and 42% (n = 29/69), respectively. The difference in the contamination rate between groups was not statistically significant (P = .109). The most common organisms identified were Staphylococcus aureus (40%) in the control group and Staphylococcus epidermidis (24.1%) and Bacillus species (20.7%) in the dropped group. The contamination level (CFUs/g) for both groups was low. The median (range) CFUs/g among the contaminated specimens in the dropped and control groups were 27 (1-120) and 3 (1-15), respectively (P < .0001). A relatively high rate of OC autograft contamination can be expected during harvesting and preparation (29%) or after accidentally dropping a specimen (42%). Although the types of organisms isolated differed between specimens contaminated during harvesting and preparation and

  16. Can Competitive Athletes Return to High-Level Play After Osteochondral Allograft Transplantation of the Knee?

    PubMed

    McCarthy, Mark A; Meyer, Maximilian A; Weber, Alexander E; Levy, David M; Tilton, Annemarie K; Yanke, Adam B; Cole, Brian J

    2017-09-01

    To investigate functional outcomes among competitive athletes undergoing osteochondral allograft (OCA) transplantation of the knee, including rates of return to play (RTP), and factors preventing RTP. A retrospective review identified all competitive athletes (high school, intercollegiate, professional) undergoing isolated femoral condyle OCA from 2004 to 2013. Patient-reported outcome (PRO) questionnaires (Lysholm, International Knee Documentation Committee [IKDC], Knee Injury and Osteoarthritis Outcome Score [KOOS], Western Ontario and McMasters Universities Arthritis Index [WOMAC], 12-Item Short Form Health Survey [SF-12], Tegner, and Marx) and custom RTP surveys were administered. All subsequent reoperations were documented. Thirteen athletes (4 intercollegiate, 9 high-school) were identified with an average follow-up of 5.9 ± 2.5 years. Seven athletes (54%) returned to competitive sport at an average of 7.9 ± 3.5 months, 5 of whom returned to preinjury functional levels. Of the 8 athletes who either did not return to competitive sport or failed to sustain their high level of play, the most common reasons cited were graduation from high school or college (4 patients, 50%) or fear of reinjury (3 patients, 38%). All 4 patients citing graduation as the primary factor preventing return to preinjury level of competitive sport resumed recreational sport without limitations, yielding an adjusted RTP rate of 10 patients (77%) who either returned to competitive play or believed they could return if they had not graduated. At final follow-up, athletes reported significant improvements in all PRO scores except for KOOS-Sport, WOMAC-Stiffness, and SF-12 Mental subscales. There were 3 reoperations at an average of 3.8 ± 3.3 years after the index OCA. There were no instances of graft failure. OCAs provide an adjusted RTP rate of 77% for high-level adolescent athletes. Social factors may be more likely than persistent pain to prevent return to sport. Level IV

  17. Osteochondral Allograft Donor-Host Matching by the Femoral Condyle Radius of Curvature.

    PubMed

    Bernstein, Derek T; O'Neill, Craig A; Kim, Ryan S; Jones, Hugh L; Noble, Philip C; Harris, Joshua D; McCulloch, Patrick C

    2017-02-01

    Conventional osteochondral allograft (OCA) matching, requiring orthotopic, size-matched condyles, and narrow surgical time windows often prohibit timely transplantation. The femoral condyle radius of curvature (RoC) is an appropriate, isolated criterion for donor-host matching in fresh OCAs, potentially enhancing matching efficiency when compared with conventional matching techniques. Descriptive laboratory study. In part 1 of this study, 3-dimensional digital reconstructions of 14 randomly selected, cadaveric distal femoral hemicondyles were performed. Each condyle was divided into anterior, middle, and posterior zones. A virtual best-fit grid was applied to each, and each zone's sagittal- and coronal-plane RoCs were determined. Seven nonorthotopic OCA transplantations were performed based on RoC matching with 1-mm tolerance, and the preoperative and postoperative surface geometry were quantified to assess the accuracy of articular surface restoration. Of note, each donor-host pair did not match by the conventional method. In part 2 of this study, 12 cadaveric distal femora were categorized by size and digitized in the aforementioned manner. Simulated circular defects measuring 20, 25, and 30 mm in diameter were introduced into each zone. OCA matches were determined based on donor and host RoCs, and the total number of potential matches (of 71 total comparisons) was recorded as a percentage for each simulated defect. Finally, the results of RoC matching were compared with the conventional method for simulated defects in all zones of both the medial and lateral femoral condyles. Part 1: The mean surface deviation after OCA transplantation was -0.09 mm, with a mean maximum protrusion at any point of 0.59 mm. Part 2: Using the RoC, 20-mm defects had a 100% chance of being matched. Defects of 25 and 30 mm had a 91% and 64% chance of being matched, respectively. Compared with the conventional method, the RoC method yielded a 3.2-fold greater match rate for lesions of

  18. Hybrid quantum circuit with implanted erbium ions

    SciTech Connect

    Probst, S.; Rotzinger, H.; Tkalčec, A.; Kukharchyk, N.; Wieck, A. D.; Wünsch, S.; Siegel, M.; Ustinov, A. V.; Bushev, P. A.

    2014-10-20

    We report on hybrid circuit quantum electrodynamics experiments with focused ion beam implanted Er{sup 3+} ions in Y{sub 2}SiO{sub 5} coupled to an array of superconducting lumped element microwave resonators. The Y{sub 2}SiO{sub 5} crystal is divided into several areas with distinct erbium doping concentrations, each coupled to a separate resonator. The coupling strength is varied from 5 MHz to 18.7 MHz, while the linewidth ranges between 50 MHz and 130 MHz. We confirm the paramagnetic properties of the implanted spin ensemble by evaluating the temperature dependence of the coupling. The efficiency of the implantation process is analyzed and the results are compared to a bulk doped Er:Y{sub 2}SiO{sub 5} sample. We demonstrate the integration of these engineered erbium spin ensembles with superconducting circuits.

  19. Dental Implant Surgery

    MedlinePlus

    Dental implant surgery Overview By Mayo Clinic Staff Dental implant surgery is a procedure that replaces tooth roots ... that look and function much like real ones. Dental implant surgery can offer a welcome alternative to dentures ...

  20. Hip Implant Systems

    MedlinePlus

    ... Medical Devices Products and Medical Procedures Implants and Prosthetics Metal-on-Metal Hip Implants Hip Implants Share ... femoral head) is removed and replaced with a prosthetic ball made of metal or ceramic, and the ...

  1. Knee Osteochondritis Dissecans Treated by the AO Hook Fixation System: A Four Year Follow-Up of an Alternative Technique

    PubMed Central

    Pengas, Ioannis P; Assiotis, Angelos; Kokkinakis, Michail; Khan, Wasim S; Meyers, Paul; Arbuthnot, James; Mcnicholas, Michael J

    2014-01-01

    Surgical fixation is recommended for stable osteochondritis dissecans (OCD) lesions that have failed nonoperative management and for all unstable lesions. In this study we set out to describe and evaluate an alternative method of surgical fixation for such lesions. Five knees with unstable OCD lesions in four male adolescent patients with open physes were treated with the AO Hook Fixation System. The outcome was evaluated both clinically and with three separate outcome systems (IKDC 2000, KOOS, Lysholm) at one and a mean four year follow-up. We demonstrated excellent clinical results in all patients. At four years, all scoring systems demonstrated statistically significant improvement when compared to the preoperative status. Our study suggests that the AO Hook Fixation System is an alternative method of surgical intervention with comparable medium term results with other existing modes of fixation and the added biomechanical advantage of the absence of distracting forces during hardware removal. PMID:25067976

  2. [Cochlear implants].

    PubMed

    Lehnhardt, E; Battmer, R D; Nakahodo, K; Laszig, R

    1986-07-01

    Since the middle of 1984, the HNO-Klinik der Medizinischen Hochschule Hannover has provided deaf adults with a 22-channel cochlear implant (CI) device of Clark-NUCLEUS. The digital working system consists of an implantable stimulator/receiver and an externally worn speech processor. Energy and signals are transmitted transcutaneously via a transmitter coil. During the prevailing 26 operations (April 1986) the electrode array could be inserted at least 17 mm into the cochlea. The threshold and comfort levels of all patients were adjusted very quickly; the dynamic range usually grows during the first postoperative weeks. The individual rehabilitation results vary greatly, but all patients show a significant increase of vowel and consonant comprehension while using the speech processor and an improvement of words understood per minute in speech tracking from lip-reading alone to lip-reading with speech processor. Four months after surgery seven of 17 patients (group I) are able to understand on average 42.7 words per minute by speech tracking without lip-reading. Six patients (group II) recognise 69.2% of vowels and 42.5% of consonants by speech processor alone. Four patients (group III) can correctly repeat only vowels (52.3%) without lip-reading, but using the speech processor together with lip reading they have an improvement in consonant understanding of 37.9% and under freefield conditions they are able to understand up to 17.8% numbers of the Freiburg speech test.

  3. Capacitive Feedthroughs for Medical Implants

    PubMed Central

    Grob, Sven; Tass, Peter A.; Hauptmann, Christian

    2016-01-01

    Important technological advances in the last decades paved the road to a great success story for electrically stimulating medical implants, including cochlear implants or implants for deep brain stimulation. However, there are still many challenges in reducing side effects and improving functionality and comfort for the patient. Two of the main challenges are the wish for smaller implants on one hand, and the demand for more stimulation channels on the other hand. But these two aims lead to a conflict of interests. This paper presents a novel design for an electrical feedthrough, the so called capacitive feedthrough, which allows both reducing the size, and increasing the number of included channels. Capacitive feedthroughs combine the functionality of a coupling capacitor and an electrical feedthrough within one and the same structure. The paper also discusses the progress and the challenges of the first produced demonstrators. The concept bears a high potential in improving current feedthrough technology, and could be applied on all kinds of electrical medical implants, even if its implementation might be challenging. PMID:27660602

  4. Functional evaluation of patients treated with osteochondral allograft transplantation for post-traumatic ankle arthritis: one year follow-up.

    PubMed

    Berti, L; Vannini, F; Lullini, G; Caravaggi, P; Leardini, A; Giannini, S

    2013-09-01

    Severe post-traumatic ankle arthritis poses a reconstructive challenge in active patients. Whereas traditional surgical treatments, i.e. arthrodesis and arthroplasty, provide good pain relief, arthrodesis is associated to functional and psychological limitations, and arthroplasty is prone to failure in the active patient. More recently the use of bipolar fresh osteochondral allografts transplantation has been proposed as a promising alternative to the traditional treatments. Preliminary short- and long-term clinical outcomes for this procedure have been reported, but no functional evaluations have been performed to date. The clinical and functional outcomes of a series of 10 patients who underwent allograft transplantation at a mean follow-up of 14 months are reported. Clinical evaluation was performed with the AOFAS score, functional assessment by state-of-the-art gait analysis. The clinical score significantly improved from a median of 54 (range 12-65) pre-op to 76.5 (range 61-86) post-op (p=0.002). No significant changes were observed for the spatial-temporal parameters, but motion at the hip and knee joints during early stance, and the range of motion of the ankle joint in the frontal plane (control: 13.8°±2.9°; pre-op: 10.4°±3.1°, post-op: 12.9°±4.2°; p=0.02) showed significant improvements. EMG signals revealed a good recovery in activation of the biceps femoris. This study showed that osteochondral allograft transplantation improves gait patterns. Although re-evaluation at longer follow-ups is required, this technique may represent the right choice for patients who want to delay the need for more invasive joint reconstruction procedures.

  5. Discrepancy between morphological findings in juvenile osteochondritis dissecans (OCD): a comparison of magnetic resonance imaging (MRI) and arthroscopy.

    PubMed

    Roßbach, Björn Peter; Paulus, Alexander Christoph; Niethammer, Thomas Richard; Wegener, Veronika; Gülecyüz, Mehmet Fatih; Jansson, Volkmar; Müller, Peter Ernst; Utzschneider, Sandra

    2016-04-01

    The aim of this study was to assess the reliability of preoperative MRI for the staging of osteochondritis dissecans (OCD) lesions of the knee and the talus in juvenile patients, using arthroscopy as the gold standard of diagnosis. Sixty-three juvenile patients (range 8-16 years) with an OCD of the knee or the talus underwent arthroscopy after MRI. In 54/9 out of 63 cases, 1.5/3 T MR scanners were used. The OCD stage was classified according the staging criteria of Dipaola et al. Arthroscopic findings were compared with MRI reports in each patient. From the 63 juvenile patients, MRI/arthroscopy revealed a stage I OCD in 4/19 patients, stage II in 31/22 patients, stage III in 22/9 patients and stage IV in 6/6 patients. No osteochondral pathology was evident in arthroscopy in seven out of 63 patients. The overall accuracy of preoperative MRI in staging an OCD lesion of the knee or the talus was 41.3%. In 33 out of 63 patients (52.4%), arthroscopy revealed a lower OCD stage than in the preoperative MRI grading, and in four out of 63 cases (6.4%), the intraoperative arthroscopic grading was worse than in preoperative MRI prior to surgery. The utilization of the 3 T MRI provided a correct diagnosis with 44.4%. Even with today's modern MRI scanners, it is not possible to predict an accurate OCD stage in children. The children's orthopaedist should not solely rely on the MRI when it comes to the decision to further conservative or surgical treatment of a juvenile OCD, but rather should take surgical therapy in consideration within persisting symptoms despite a low OCD stage provided by MRI. III.

  6. Osteochondral lesions in distal tarsal joints of Icelandic horses reveal strong associations between hyaline and calcified cartilage abnormalities.

    PubMed

    Ley, C J; Ekman, S; Hansson, K; Björnsdóttir, S; Boyde, A

    2014-03-25

    Osteochondral lesions in the joints of the distal tarsal region of young Icelandic horses provide a natural model for the early stages of osteoarthritis (OA) in low-motion joints. We describe and characterise mineralised and non-mineralised osteochondral lesions in left distal tarsal region joint specimens from twenty-two 30 ±1 month-old Icelandic horses. Combinations of confocal scanning light microscopy, backscattered electron scanning electron microscopy (including, importantly, iodine staining) and three-dimensional microcomputed tomography were used on specimens obtained with guidance from clinical imaging. Lesion-types were described and classified into groups according to morphological features. Their locations in the hyaline articular cartilage (HAC), articular calcified cartilage (ACC), subchondral bone (SCB) and the joint margin tissues were identified and their frequency in the joints recorded. Associations and correlations between lesion-types were investigated for centrodistal joints only. In centrodistal joints the lesion-types HAC chondrocyte loss, HAC fibrillation, HAC central chondrocyte clusters, ACC arrest and ACC advance had significant associations and strong correlations. These lesion-types had moderate to high frequency in centrodistal joints but low frequencies in tarsometatarsal and talocalcaneal-centroquartal joints. Joint margin lesion-types had no significant associations with other lesion-types in the centrodistal joints but high frequency in both the centrodistal and tarsometatarsal joints. The frequency of SCB lesion-types in all joints was low. Hypermineralised infill phase lesion-types were detected. Our results emphasise close associations between HAC and ACC lesions in equine centrodistal joints and the importance of ACC lesions in the development of OA in low-motion compression-loaded equine joints.

  7. Implant marketing: cost effective implant dentistry.

    PubMed

    Wohrle, P S; Levin, R P

    1996-01-01

    The application of the KAL-Technique to the field of implant dentistry allows both patients and dental practices to benefit. It is an exciting advance that decreases frustration and stress in providing implant procedures and lowers overall costs. Professionals using the KAL-Technique report significant predictability in achieving passive framework fit. They are also lowering overall cost of implant cases, which increases the number of patients who can accept implant treatment. It has been well established that the more individuals in a practice that receive implants, the more referrals a practice will gain. This is because implant patients find tremendous advances in the quality of life, and do not hesitate to tell others who can take advantage of this opportunity. Implant dentistry is one of the fastest growing fields in dentistry today. While some other areas of dentistry begin to decline in volume and need, implant dentistry provides the opportunity to keep practices strong and to insure long-term success.

  8. Distant energy transfer for artificial human implants.

    PubMed

    Theodoridis, Michael P; Mollov, Stefan V

    2005-11-01

    The powering of human implants via inductive coupling has been an object of interest for the past two decades. This paper discusses some of the issues concerning a distant energy link used for supplying artificial human implants, operating at the frequency of 13.56 MHz. A procedure for the design of an energy-receiving coil is given for general applications. A design procedure is also developed, with focus on coils used for supplying human implants. The correctness of the analysis of this later design procedure has been verified by experimental results. Measurements with a human tissue simulant also show little deviation from the predictions.

  9. Cumulative Incidence of Osteochondritis Dissecans of the Capitellum in Child and Adolescent Baseball Players

    PubMed Central

    Iwame, Toshiyuki; Matsuura, Tetsuya; Suzue, Naoto; Sairyo, Koichi

    2016-01-01

    Objectives: Prevalence of osteochondritis dissecans (OCD) of the capitellum is high among individuals who have played baseball since childhood. Recently two cross-sectional studies according to prevalence of OCD have been published. In a study of 1040 baseball players aged 10 to 12 years, Matsuura et al found that 2.1% of players had OCD, with no differences in prevalence according to age or player position. Kida et al., in their study of 2433 baseball players aged 12 to 18 years, found OCD in 3.4% of subjects. Furthermore, they found that players with OCD began playing baseball at earlier ages, had played for longer periods, and had experienced more elbow pain. The player’s current baseball position may not be related to the existence of OCD lesions. Together, these findings led us to examine the longitudinal study for examining the risk factors for occurrence of OCD. Our objectives were to determine (1) cumulative incidence rates of OCD in the school child players aged 6-11 years old, (2) the relative risk of OCD by age, beginning age playing baseball, playing period, experimental hours per week, playing position, and elbow pain. Methods: A total of 1,275 players aged 6-11 years (mean, 9.4 years) belonged to youth baseball teams without OCD lesions received examination in the next year and were the subjects of this investigation. Subjects were examined by questionnaire, and ultrasonographic and radiographic examination. Questionnaire items included age, player position, beginning age of playing baseball, playing period of baseball, number of training hours per week and history of elbow pain. Ultrasonography of the lateral aspect of the elbow was performed. An irregularity of the subchondral bone of the capitellum was regarded as an abnormality. Radiographic examination was recommended to players who had an abnormal finding on ultrasonographic examination. We investigated the following risk factors for occurrence of OCD: age, player position, beginning age of

  10. A rare case of an osteochondral lesion of the tarsal navicular with a subacute stress fracture in a high level athlete.

    PubMed

    Nunag, Perrico; Quah, Colin; Pillai, Anand

    2014-12-01

    In this report, an osteochondral lesion of the tarsal navicular associated with a subacute stress fracture in a professional basketball player surgical treatment is presented. The surgical technique involved extra-articular curettage, bone grafting and plate stabilisation. Postoperative CT scan confirmed that both the osteochondral lesion and the stress fracture healed. The talonavicular joint showed no signs of arthritis on imaging. Clinical foot scores showed marked improvement after surgery. At 6 months patient managed to return to competitive play without pain in the foot and ankle. The outcome of this case indicates that the combination of curettage, bone grating and plate stabilisation works well for this rare and potentially career ending dual lesions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Establishing proof of concept: Platelet-rich plasma and bone marrow aspirate concentrate may improve cartilage repair following surgical treatment for osteochondral lesions of the talus.

    PubMed

    Smyth, Niall A; Murawski, Christopher D; Haleem, Amgad M; Hannon, Charles P; Savage-Elliott, Ian; Kennedy, John G

    2012-07-18

    Osteochondral lesions of the talus are common injuries in the athletic patient. They present a challenging clinical problem as cartilage has a poor potential for healing. Current surgical treatments consist of reparative (microfracture) or replacement (autologous osteochondral graft) strategies and demonstrate good clinical outcomes at the short and medium term follow-up. Radiological findings and second-look arthroscopy however, indicate possible poor cartilage repair with evidence of fibrous infill and fissuring of the regenerative tissue following microfracture. Longer-term follow-up echoes these findings as it demonstrates a decline in clinical outcome. The nature of the cartilage repair that occurs for an osteochondral graft to become integrated with the native surround tissue is also of concern. Studies have shown evidence of poor cartilage integration, with chondrocyte death at the periphery of the graft, possibly causing cyst formation due to synovial fluid ingress. Biological adjuncts, in the form of platelet-rich plasma (PRP) and bone marrow aspirate concentrate (BMAC), have been investigated with regard to their potential in improving cartilage repair in both in vitro and in vitro settings. The in vitro literature indicates that these biological adjuncts may increase chondrocyte proliferation as well as synthetic capability, while limiting the catabolic effects of an inflammatory joint environment. These findings have been extrapolated to in vitro animal models, with results showing that both PRP and BMAC improve cartilage repair. The basic science literature therefore establishes the proof of concept that biological adjuncts may improve cartilage repair when used in conjunction with reparative and replacement treatment strategies for osteochondral lesions of the talus.

  12. Combination therapy with intra-articular injection of mesenchymal stem cells and articulated joint distraction for repair of a chronic osteochondral defect in the rabbit.

    PubMed

    Harada, Yohei; Nakasa, Tomoyuki; Mahmoud, Elhussein Elbadry; Kamei, Goki; Adachi, Nobuo; Deie, Masataka; Ochi, Mitsuo

    2015-10-01

    The present study investigated intra-articular injection of bone-marrow-derived mesenchymal stem cells (MSCs) combined with articulated joint distraction as treatment for osteochondral defects. Large osteochondral defects were created in the weight-bearing area of the medial femoral condyle in rabbit knees. Four weeks after defect creation, rabbits were divided into six groups: control group, MSC group, distraction group, distraction + MSC group, temporary distraction group, and temporary distraction + MSC group. Groups with MSC received intra-articular injection of MSCs. Groups with distraction underwent articulated distraction arthroplasty. Groups with temporary distraction discontinued the distraction after 4 weeks. The rabbits were euthanized at 4, 8, and 12 weeks after treatment except temporary distraction groups which were euthanized at only 12 weeks. Histological scores in the distraction + MSC group were significantly better than in the control, MSC group or distraction group at 4 and 8 weeks, but showed no further improvement. At 12 weeks, the temporary distraction + MSC group showed the best results, demonstrating hyaline cartilage repair with regeneration of the osteochondral junction. In conclusion, joint distraction with intra-articular injection of MSCs promotes early cartilage repair, and compressive loading of the repair tissue after temporary distraction stimulates articular cartilage regeneration. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  13. Bioprinting of a mechanically enhanced three-dimensional dual cell-laden construct for osteochondral tissue engineering using a multi-head tissue/organ building system

    NASA Astrophysics Data System (ADS)

    Shim, Jin-Hyung; Lee, Jung-Seob; Kim, Jong Young; Cho, Dong-Woo

    2012-08-01

    The aim of this study was to build a mechanically enhanced three-dimensional (3D) bioprinted construct containing two different cell types for osteochondral tissue regeneration. Recently, the production of 3D cell-laden structures using various scaffold-free cell printing technologies has opened up new possibilities. However, ideal 3D complex tissues or organs have not yet been printed because gel-state hydrogels have been used as the principal material and are unable to maintain the desired 3D structure due to their poor mechanical strength. In this study, thermoplastic biomaterial polycaprolactone (PCL), which shows relatively high mechanical properties as compared with hydrogel, was used as a framework for enhancing the mechanical stability of the bioprinted construct. Two different alginate solutions were then infused into the previously prepared framework consisting of PCL to create the 3D construct for osteochondral printing. For this work, a multi-head tissue/organ building system (MtoBS), which was particularly designed to dispense thermoplastic biomaterial and hydrogel having completely different rheology properties, was newly developed and used to bioprint osteochondral tissue. It was confirmed that the line width, position and volume control of PCL and alginate solutions were adjustable in the MtoBS. Most importantly, dual cell-laden 3D constructs consisting of osteoblasts and chondrocytes were successfully fabricated. Further, the separately dispensed osteoblasts and chondrocytes not only retained their initial position and viability, but also proliferated up to 7 days after being dispensed.

  14. Cartilage storage at 4 °C with regular culture medium replacement benefits chondrocyte viability of osteochondral grafts in vitro.

    PubMed

    Qi, Jianhong; Hu, Zunjie; Song, Hongqiang; Chen, Bin; Xie, Di; Zhou, Lu; Zhang, Yanming

    2016-09-01

    Maintenance of articular cartilage allografts in culture media is a common method of tissue storage; however, the technical parameters of graft storage remain controversial. In this study, we examined the optimal temperature and culture medium exchange rate for the storage of osteochondral allografts in vitro. Cylindrical osteochondral grafts (n = 120), harvested from the talar joint surface of ten Boer goats, were randomly classified into four groups and stored under the following conditions: Group A1 was maintained at 4 °C in culture medium that was refreshed every 2 days; Group A2 was maintained at 4 °C in the same culture medium, without refreshing; Group B1, was maintained at 37 °C in culture medium that was refreshed every 2 days; Group B2, was maintained at 37 °C in the same culture medium, without refreshing. Chondrocyte viability in the grafts was determined by ethidium bromide/fluorescein diacetate staining on days 7, 21, and 35. Proteoglycan content was measured by Safranin-O staining. Group A1 exhibited the highest chondrocyte survival rates of 90.88 %, 88.31 % and 78.69 % on days 7, 21, and 35, respectively. Safranin O staining revealed no significant differences between groups on days 21 and 35. These results suggest that storage of osteochondral grafts at 4 °C with regular culture medium replacement should be highly suitable for clinical application.

  15. [Bilateral cochlear implantation].

    PubMed

    Kronenberg, Jona; Migirov, Lela; Taitelbaum-Swead, Rikey; Hildesheimer, Minka

    2010-06-01

    Cochlear implant surgery became the standard of care in hearing rehabilitation of patients with severe to profound sensorineural hearing loss. This procedure may alter the lives of children and adults enabling them to integrate with the hearing population. In the past, implantation was performed only in one ear, despite the fact that binaural hearing is superior to unilateral, especially in noisy conditions. Cochlear implantation may be performed sequentially or simultaneously. The "sensitive period" of time between hearing loss and implantation and between the two implantations, when performed sequentially, significantly influences the results. Shorter time spans between implantations improve the hearing results after implantation. Hearing success after implantation is highly dependent on the rehabilitation process which includes mapping, implant adjustments and hearing training. Bilateral cochlear implantation in children is recommended as the proposed procedure in spite of the additional financial burden.

  16. A novel method for effective sodium ion implantation into silicon.

    PubMed

    Lu, Qiu Yuan; Chu, Paul K

    2012-07-01

    Although sodium ion implantation is useful to the surface modification of biomaterials and nano-electronic materials, it is a challenging to conduct effective sodium implantation by traditional implantation methods due to its high chemical reactivity. In this paper, we present a novel method by coupling a Na dispenser with plasma immersion ion implantation and radio frequency discharge. X-ray photoelectron spectroscopy (XPS) depth profiling reveals that sodium is effectively implanted into a silicon wafer using this apparatus. The Na 1s XPS spectra disclose Na(2)O-SiO(2) bonds and the implantation effects are confirmed by tapping mode atomic force microscopy. Our setup provides a feasible way to conduct sodium ion implantation effectively.

  17. A novel method for effective sodium ion implantation into silicon

    SciTech Connect

    Lu Qiuyuan; Chu, Paul K.

    2012-07-15

    Although sodium ion implantation is useful to the surface modification of biomaterials and nano-electronic materials, it is a challenging to conduct effective sodium implantation by traditional implantation methods due to its high chemical reactivity. In this paper, we present a novel method by coupling a Na dispenser with plasma immersion ion implantation and radio frequency discharge. X-ray photoelectron spectroscopy (XPS) depth profiling reveals that sodium is effectively implanted into a silicon wafer using this apparatus. The Na 1s XPS spectra disclose Na{sub 2}O-SiO{sub 2} bonds and the implantation effects are confirmed by tapping mode atomic force microscopy. Our setup provides a feasible way to conduct sodium ion implantation effectively.

  18. Topical Review: MACI as an Emerging Technology for the Treatment of Talar Osteochondral Lesions.

    PubMed

    Dekker, Travis J; Erickson, Brandon; Adams, Samuel B; Gross, Christopher E

    2017-09-01

    Matrix-induced autologous chondrocyte implantation (MACI) is a viable procedure that can be used as both a primary or revision cartilage regenerative procedure in high-functioning individuals without tibiotalar arthritis. Both short-term and midterm follow-up results demonstrate clinical, radiographic, and functional improvements with high rates of return to full activities. Cost remains a chief concern with the use of this technique, but theoretical improvements in the durability of repair with type II cartilage replacement may offer long-term benefits. Level V, expert opinion.

  19. The effect of defect localization on spontaneous repair of osteochondral defects in a Gottingen minipig model: a retrospective analysis of the medial patellar groove versus the medial femoral condyle.

    PubMed

    Jung, Martin; Breusch, Steffen; Daecke, Wolfgang; Gotterbarm, Tobias

    2009-04-01

    Various animal models for experimental osteochondral defect healing have been used in orthopaedic research. Two main defect locations were chosen: the patellar groove or the central part of the medial femoral condyles (MFC). To date, it is not clear whether both locations display similar patterns in critical size osteochondral defect healing. We retrospectively analysed both locations in our minipig model hypothesizing that they show similar healing pattern. Thirty-five defects were analysed after three or 12 months. Osteochondral defects were 10 mm deep and 6.3 mm (MFC, n = 19) in diameter or 8 mm and 5.4 mm, respectively (trochlear groove [TG], n = 16). Semi-quantitative histological scoring and histomorphological evaluation were carried out. Both defect locations showed fillings of fibrous and fibrocartilage-like repair tissue. The osseous defect was closed by endochondral bone formation in the MFC. Semi-quantitative scoring did not show differences, whereas qualitative histomorphological analysis more frequently showed cartilaginous repair tissue in MFC defects. There was more frequent subchondral bone cyst formation in MFC location (P = 0.05), TG defects resulted in lower postoperative pain. Both defect localizations are suitable for studies on osteochondral healing. Since regenerating with less hyaline-like repair tissue and less subchondral cyst formation, TG is more favourable for experimental osteochondral defect healing in this model.

  20. Parents' narratives on cochlear implantation: reconstructing the experience of having a child with cochlear implant.

    PubMed

    Peñaranda, Augusto; Suárez, Roberto M; Niño, Natalia M; Aparicio, Maria Leonor; García, Juan Manuel; Barón, Clemencia

    2011-08-01

    This paper discusses parents' narratives on cochlear implantation in Bogotá, Colombia using a qualitative approach. The main research objective was to identify how parents perceived the processes of diagnosis of their child's hearing loss, making the decision for cochlear implantation and the post-surgery period. All participants were hearing couples (n = 13) with similar socio-cultural backgrounds whose children had undergone cochlear implant surgery. Results show why cochlear implants are a very highly valued technological device with great symbolic power for parents. The study also deals with how perceptions about oral/sign language and disability, as well as social expectations for their children's lifetime opportunities, determine how the parents themselves have experienced their journey through the process of their children's cochlear implantation.