-
[show abstract]
[hide abstract]
ABSTRACT: The ideal artificial ligament graft should have favorable biocompatibility to facilitate cell adhesion, proliferation, and collagen regeneration. In this present study, surface modification was performed on a poly(ethylene terephthalate) (PET) artificial ligament graft by layer-by-layer (LBL) self-assembly coating of hyaluronic acid (HA) and chitosan (CS). The surface characterization of the ligament was examined using scanning electron microscopy, atomic force microscopy, and energy-dispersive X-ray spectroscopy. The results of in vitro culturing of human foreskin fibroblast cells supported the hypothesis that the LBL coating of CS-HA could promote the cell proliferation and adhesion on the sheets. A rabbit medical collateral ligament reconstruction model was used to evaluate the effect of this LBL coating in vivo. The final results proved that this LBL coating could significantly promote and enhance new collagen formation among the graft fibers. On the basis of these results, we conclude that such CS-HA assembly coating could enhance PET graft biocompatibility in vitro and in vivo, and a CS-HA-coated PET graft has considerable potential as a desirable substitute for ligament reconstruction.
Journal of Biomaterials Science Polymer Edition 03/2013; 24(4):431-46. · 1.69 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: A novel hydroxyapatite/regenerated silk fibroin scaffold was prepared and investigated for its potential to enhance both osteoinductivity and osteoconductivity of bone marrow-derived mesenchymal stromal cells in vitro. Approx. 12.4 ± 0.06 % (w/w) hydroxyapatite was deposited onto the scaffold, and cell viability and DNA content were significantly increased (18.5 ± 0.6 and 33 ± 1.2 %, respectively) compared with the hydroxyapatite scaffold after 14 days. Furthermore, alkaline phosphatase activity in the novel scaffold increased 41 ± 2.5 % after 14 days compared with the hydroxyapatite scaffold. The data indicate that this novel hydroxyapatite/regenerated silk fibroin scaffold has a positive effect on osteoinductivity and osteoconductivity, and may be useful for bone tissue engineering.
Biotechnology Letters 12/2012; · 1.68 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: PURPOSE: The aim of this study was to determine whether hydroxypropylcellulose (HPC) coating of polyethylene terephthalate (PET) artificial ligaments enhances graft osseointegration in the bone tunnel. METHODS: Thirty New Zealand white rabbits underwent artificial ligament graft transplantation in the bilateral proximal tibia tunnels. One limb was implanted with an HPC-coated PET graft, and the contralateral limb was implanted with a non-HPC-coated PET graft as a control. The rabbits were then randomly sacrificed at weeks four and eight after surgery for biomechanical testing, histological examination, and histomorphometric and real-time polymerase chain reaction analysis. RESULTS: At week four after surgery, there were no statistically significant differences in the load to failure or stiffness values between the experimental and control limbs (P = 0.328 and P = 0.128, respectively). At week eight after surgery, the mean load to failure and stiffness value of the experimental limbs was higher than that of the control limbs (P < 0.001 and P = 0.018, respectively). At week eight after surgery, some protruding new bone tissue from the host bone to the graft was found in the HPC-coated group, while a thick fibrous tissue band was observed at the interface between the graft and the host bone in the control group. Histomorphometric analysis showed that the graft-bone interface width in the HPC-coated group was significantly narrower than that in the control group at week eight after surgery (P < 0.001). At weeks four and eight after surgery, the mRNA expression level of bone morphogenetic protein-2 in the HPC group was higher than that in the control group (P = 0.001 and P = 0.010, respectively). The mRNA expression level of osteopontin in the HPC group was higher than that in the control group only at week four after surgery (P = 0.032). CONCLUSIONS: Our data show that an HPC coating on the surface of PET artificial ligament grafts may induce artificial ligament graft osseointegration in the bone tunnel.
International Orthopaedics 11/2012; · 2.03 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: PURPOSE: The aim of this study was to investigate whether cationised gelatin and hyaluronic acid (CH) coating could induce polyethylene terephthalate (PET) artificial ligament graft osseointegration in the bone tunnel. METHODS: Surface modification of PET artificial ligament graft was performed by layer-by-layer (LBL) self-assembly CH coating. Six pigs underwent anterior cruciate ligament (ACL) reconstruction on the right knees, with three pigs receiving the CH-coated PET grafts and the other three pigs non-CH-coated PET grafts as controls. They were sacrificed at three months after surgery and the graft-bone complexes were acquired for computed tomography (CT) scan and histological examination. RESULTS: CT scans showed a significant difference at the distal femoral site (p = 0.031) or at the distal tibial site (p = 0.0078), but no significant difference in the bone tunnel areas' enlargement at other sites (p > 0.05) between the CH group and the control group. Histologically, application of CH coating induced new bone formation between graft and bone at three months compared with the controls at the distal site. The interface width of the CH group was significantly lower than that of the control group at the distal femoral site (p = 0.0327) and at the distal tibial site (p = 0.0047). CONCLUSIONS: The study has shown that CH coating on the PET artificial ligament surface has a positive biological effect in the induction of artificial ligament osseointegration within the bone tunnel at the distal site of the bone tunnel.
International Orthopaedics 11/2012; · 2.03 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In this study layer by layer (LBL) self-assembled coatings of hyaluronic acid (HA) and cationized gelatin (CG) were used to modify polyethylene terephthalate (PET) artificial ligament grafts. Changes in the surface properties were characterized by scanning electron microscopy, attenuated total reflection Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and contact angle and biomechanical measurements. The cell compatibility of this HA-CG coating was investigated in vitro on PET films seeded with human foreskin dermal fibroblasts over 7days. The results of our in vitro studies demonstrated that the HA-CG coating significantly enhanced cell adhesion, facilitated cell growth, and suppressed the expression of inflammation-related genes relative to a pure PET graft. Furthermore, rabbit and porcine anterior cruciate ligament reconstruction models were used to evaluate the effect of this LBL coating in vivo. The animal experiment results proved that this LBL coating significantly inhibited inflammatory cell infiltration and promoted new ligament tissue regeneration among the graft fibers. In addition, the formation of type I collagen in the HA-CG coating group was much higher than in the control group. Based on these results we conclude that PET grafts coated with HA-CG have considerable potential as substitutes for ligament reconstruction.
Acta biomaterialia 07/2012; 8(11):4007-19. · 3.98 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Tendon-bone healing is a progressive and complex pathophysiological process after tendon graft transplantation into a bone tunnel. A fibrous scar tissue layer forms at the graft-bone interface, which means a weak bonding of the graft in the bone tunnel. Periosteum, a favourable autologous tissue, was confirmed to be effective in promoting tendon-bone healing in the human body. The advantages of a periosteum patch for tendon-bone repair include the fact that this tissue meets the three primary requirements for tissue engineering: a source of progenitor cells, a scaffold for recruiting cells and growth factors, and a source of local growth factors. Furthermore, the periosteum can prevent graft micromotion, alleviate inflammation and deter bone resorption. In this review, we highlight the role of progenitor cells in the periosteum, which contribute to the regeneration of new bone and/or fibrocartilage at the tendon-bone interface. In summary, the periosteum has shown significant potential for use in the enhancement of graft-bone healing. Our investigations may provoke further studies on the management of allograft-bone healing and artificial ligament graft healing using a periosteum patch in future.
International Orthopaedics 03/2012; 36(3):665-9. · 2.03 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: A ligament advanced reinforcement system (LARS) artificial ligament has been proposed for use in anterior cruciate ligament reconstruction in some cases, and an emerging body of reports has shown its success in the short term. However, there are great concerns about the potential risks of complications, which might prevent its extensive use. We report a rare case of serious synovitis 3 years postoperatively in a 26-year-old man who underwent LARS artificial ligament reconstruction. During revision arthroscopy, we observed a large amount of synovial hyperplasia in the knee joint, containing a large amount of hemosiderin deposition. In addition, the femoral tunnel was placed too anteriorly, and the ligament was ruptured near the tibial tunnel. Histologically, there was thick fibrous scar tissue around the graft, and poorly organized fibrous scar tissue infiltrated into the graft fibers, which could cause loss of structural integrity of the ligament and eventual graft failure. Collectively, our findings might arouse further in-depth research on the development of artificial ligament.
Arthroscopy The Journal of Arthroscopic and Related Surgery 02/2012; 28(4):583-6. · 3.02 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: At present, due to the growing attention focused on the issue of tendon-bone healing, we carried out an animal study of the use of genetic intervention combined with cell transplantation for the promotion of this process. Here, the efficacy of bone marrow stromal cells infected with bone morphogenetic protein-2 (BMP-2) on tendon-bone healing was determined. A eukaryotic expression vector containing the BMP-2 gene was constructed and bone marrow-derived mesenchymal stem cells (bMSCs) were infected with a lentivirus. Next, we examined the viability of the infected cells and the mRNA and protein levels of BMP-2-infected bMSCs. Gastrocnemius tendons, gastrocnemius tendons wrapped by bMSCs infected with the control virus (bMSCs+Lv-Control), and gastrocnemius tendons wrapped by bMSCs infected with the recombinant BMP-2 virus (bMSCs+Lv-BMP-2) were used to reconstruct the anterior cruciate ligament (ACL) in New Zealand white rabbits. Specimens from each group were harvested four and eight weeks postoperatively and evaluated using biomechanical and histological methods. The bMSCs were infected with the lentivirus at an efficiency close to 100%. The BMP-2 mRNA and protein levels in bMSCs were significantly increased after lentiviral infection. The bMSCs and BMP-2-infected bMSCs on the gastrocnemius tendon improved the biomechanical properties of the graft in the bone tunnel; specifically, bMSCs infected with BMP-2 had a positive effect on tendon-bone healing. In the four-week and eight-week groups, bMSCs+Lv-BMP-2 group exhibited significantly higher maximum loads of 29.3 ± 7.4 N and 45.5 ± 11.9 N, respectively, compared with the control group (19.9 ± 6.4 N and 21.9 ± 4.9 N) (P = 0.041 and P = 0.001, respectively). In the eight-week groups, the stiffness of the bMSCs+Lv-BMP-2 group (32.5 ± 7.3) was significantly higher than that of the bMSCs+Lv-Control group (22.8 ± 7.4) or control groups (12.4 ± 6.0) (p = 0.036 and 0.001, respectively). Based on the histological findings, there was an increased amount of perpendicular collagen fibers formed between the tendon and bone in the bMSCs+Lv-Control and bMSCs+Lv-BMP-2 group, compared with the gastrocnemius tendons. The proliferation of cartilage-like cells and the formation of fibrocartilage-like tissue were highest within the bone tunnels in the bMSCs+Lv-BMP-2 group. These results suggest that this lentivirus can be used to efficiently infect bMSCs with BMP-2. Furthermore, tendons wrapped by bMSCs+Lv-BMP-2 improved tendon-bone healing.
International Journal of Molecular Sciences 01/2012; 13(10):13605-20. · 2.60 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The aim of the study was to investigate whether a bioactive glass (BG) coating on the polyethylene terephthalate (PET) artificial ligament could enhance graft osseointegration by promoting bone regeneration at the interface between PET graft and bone tunnel.
Thirty New Zealand white rabbits underwent artificial ligament graft transplantation in proximal tibial tunnels bilaterally. One limb was implanted with a 58S BG-coated PET graft, and the contralateral limb was implanted with a non-BG-coated PET graft as a control. The rabbits were randomly sacrificed at three, six and 12 weeks after surgery for biomechanical and histological examinations.
The maximum load to failures of the BG-coated experimental group were significantly higher than those of the control group at 12 weeks (p = 0.0051). Histologically, at 12 weeks, the BG-coated PET graft induced great new bone formation between graft and host bone, and the average graft-bone interface width of the BG group became significantly lower than that of the control group. Furthermore, the BG coating on the ligament graft surface also stimulated greater expression of bone morphogenetic protein 2 (BMP-2) and vascular endothelial growth factor (VEGF) around the graft in vivo compared to the control group at three weeks (p < 0.05).
This study has shown that a BG coating on the PET artificial ligament surface has a positive effect in the induction of artificial ligament osseointegration within the bone tunnel.
International Orthopaedics 05/2011; 36(1):191-7. · 2.03 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The purpose of this study was to investigate the feasibility and advantages of constructing a novel tissue engineering bone, using β-tricalcium phosphate (β-TCP) and rat bone marrow mesenchymal stem cells (MSCs), modified with human bone morphogenetic protein 2 gene (hBMP2) and human vascular endothelial growth factor 165 gene (hVEGF165), through lentiviral transfection. Both genes were successfully co-expressed in the co-transfection group for up to eight weeks confirmed by enzyme-linked immunosorbent assay (ELISA). After seeding MSCs onto the scaffolds, scanning electron microscopy (SEM) observation showed that MSCs grew and proliferated well in co-transfection group at 7 and 14 days. There was no significant difference among all the groups in hoechst DNA assay for cell proliferation for 14 days after cell seeding (P > 0.05), but the highest alkaline phosphatase (ALP) activity was observed in the co-transfection group at 14 days after cell seeding (p < 0.01). These results demonstrated that it was advantageous to construct tissue engineering bone using β-TCP combined with MSCs lentivirally co-transfected with BMP2 and VEGF165, providing an innovative way for treating bone defects.
International Journal of Molecular Sciences 01/2011; 12(3):1744-55. · 2.60 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To observe the outcome of arthroscopic meniscal plasty and suture repair to treat torn discoid lateral meniscus involving popliteal hiatus.
Between January 2008 and May 2009, 21 cases of torn discoid lateral meniscus involving popliteal hiatus were treated by arthroscopic surgery. There were 9 males and 12 females with an average age of 22.5 years (range, 12-45 years), including 12 left knees and 9 right knees. Seven cases had the history of injury and other 14 cases had uncertain trauma. The average disease duration was 6.4 months (range, 3 months to 2 years). All patients complained knee pain or locking with positive McMurray test and milling test before surgery. All cases had torn discoid lateral meniscus, and the tear extended to the popliteal hiatus, including 17 cases of complete type and 4 cases of incomplete type according to the Watanabe classification. After meniscal plasty, suture repair of torn popliteal lateral hiatus was performed. The anterior part to hiatus was repaired by the outside-in technique, and the posterior part underwent repair of all inside technique by FasT-Fix.
All wounds healed by first intention with no complications such as infection, stiffness of knee, or injury of common peroneal nerve. All patients were followed up 12-28 months with an average of 18 months. The symptoms of knee pain or locking disappeared postoperatively with negative McMurray test and milling test in all patients. The Lysholm score was improved from 54.0 +/- 13.4 to 90.0 +/- 6.6 at 12 months postoperatively, showing significant difference (t = -12.00, P = 0.00). Based on the improved Lysholm classification standard, the results were excellent in 14 cases, good in 5, and fair in 2; the excellent and good rate was 90.5%.
For torn discoid lateral meniscus involving popliteal hiatus, based on meniscal plasty, suture repair of the popliteal hiatus would contribute to preserve the peripheral part and restore its stability.
Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery 01/2011; 25(1):13-6.
-
[show abstract]
[hide abstract]
ABSTRACT: The purpose of this study was to investigate whether hydroxyapatite (HAp) coating could induce polyethylene terephthalate (PET) artificial ligament graft osseointegration in the bone tunnel. Twenty-four New Zealand white rabbits underwent artificial ligament graft transplantation in bilateral proximal tibia tunnels. One limb was implanted with HAp-coated PET graft, and the contralateral limb was implanted with non-HAp-coated PET graft as control. The rabbits were randomly sacrificed at four and eight weeks after surgery. The loads to failure of the experimental group at eight weeks were significantly higher than those of the control group (p = 0.0057). Histologically, application of HAp coating induced new bone formation between graft and bone at eight weeks compared with the controls. Real-time polymerase chain reaction examination revealed significantly elevated messenger ribonucleic acid expression levels of osteopontin and collagen I in the grafts of the HAp group compared with the controls at four weeks (p < 0.05). The study has shown that HAp coating on the PET artificial ligament surface has a positive effect in the induction of artificial ligament osseointegration within the bone tunnel.
International Orthopaedics 11/2010; 35(10):1561-7. · 2.03 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Displaced comminuted of the distal humerus in adults are among the most complex fractures to be managed effectively. The ulnar nerve is at high risk of impingement secondary to injury, operation, and postoperative rehabilitation in these fractures. In this study we focus on the incidence, management, and prognosis of early ulnar nerve dysfunction in the course of treating type C fractures of distal humerus.
We examine a patient sample of 117 consecutive AO type C fractures of distal humerus, between June 1998 and October 2005. Twenty-nine patients exhibited preoperative ulnar nerve compression symptoms (incidence 24.8%) and were divided into two groups randomly, which received treatment of anterior subfascial transposition or in situ decompression of the ulnar nerve respectively, in conjunction with internal fixation with medial and lateral plates.
The subgroup of 88 patients without preoperative ulnar nerve symptoms remained asymptomatic postoperatively (0% incidence of late ulnar nerve dysfunction). According to Bishop rating system, excellent and good results of ulnar nerve function were achieved in 13 of 15 patients (86.7%) in the transposition group, 8 of 14 patients (57.1%) in the in situ decompression group. The results difference is statistically significant (p < 0.05).
We conclude that neurolysis and anterior subfascial transposition of vascularized ulnar nerve during open reduction and internal fixation of type C fractures of the distal humerus is beneficial in cases of early ulnat nerve dysfunction.
The Journal of trauma 09/2009; 67(6):1397-401. · 2.48 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We proposed a novel combined gene therapy of human vascular endothelial growth factor 165 gene (hVEGF165) and human bone morphogenetic protein 2 gene (hBMP2) for bone regeneration by lentivirus-mediated co-transfection of both genes into rat bone marrow-derived mesenchymal stromal cells (MSCs). Both genes were successfully co-expressed in MSCs confirmed by real-time PCR and ELISA. And the alkaline phosphatase activity of MSCs was significantly augmented by the co-transfection with both genes than any single gene transfection (P < 0.01). These results demonstrated the feasibility of the combined gene therapy by using MSCs lentivirally co-transfected with hVEGF165 and hBMP2 for bone regeneration.
Biotechnology Letters 02/2008; 30(2):197-203. · 1.68 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To study the proliferation of artery after hydraulic dilation under different pressures.
Right carotid arteries of New Zealand white rabbits (group A, B, C, D) were dilated by hydraulic dilation under different pressures (0, 40, 80, 120 Kpa). The arterial caliber, thickness of tunica intima (TI) and smooth muscle (SM) were measured with TJTY-300 automatic medical photograph analyzer at 0, 1, 2 weeks, respectively after dilation.
1) The arterial caliber of group B was greater than that in group A (P < 0.05, P < 0.01) at 0 and 1 week after hydraulic dilation, but no difference was found in 2 weeks after dilation. The thickness of TI and SM of group B was not different from group A at every time point. 2) The arterial calibers of group C, D were significantly larger than that of group A immediately and at 1 week (P < 0.01, P < 0.01). Group B, D showed no difference with group A (P > 0.05) at 2 weeks. The thickness of TI and SM of group C, D had no difference with group A (P > 0.05) immediately, but greater than group A at 1 and 2 weeks (P < 0.01, P < 0.01).
1) Arterial caliber can be increased by hydraulic dilation under different pressures. But hydraulic dilation over 80 Kpa pressure may lead to proliferation of TI and SM. 2) It is safe for arterial hydraulic dilation to be conducted under pressure of 40 Kpa.
Microsurgery 01/2008; 28(1):76-81. · 1.61 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To employ reverse first dorsal metatarsal artery island flap to recover the donor site of great toe after free lateral pulp flap transfer, and decrease the morbidity of microsurgical donor site.
From February 2000 to June 2004, 12 cases of soft tissue defect in thumb and finger were treated by free lateral pulp flap of great toe transplantation, and that the secondary defect of great toes were repaired by reverse first dorsal metatarsal artery flap according to the anatomical communicating between first dorsal metatarsal artery and plantar metatarsal artery. The donor exposure of dorsal pedis were straightly sutured.
All the lateral pulp flaps of great toe and the reversed first dorsal metatarsal flaps survived uneventfully with desirable appearance and sensation. In thumb and finger defect reconstructed with lateral pulp flaps of the great toe, there was in mean static two-point discrimination of 6 mm at 10 month follow-up, that was 10 mm in reverse flaps.
It is an instructive and practical creation to adopt the reverse first dorsal metatarsal artery flap to recover the raw surface in the lateral aspect of the great toe, which minimizes the morbidity at the donor site and gains the twin-win results.
Zhonghua zheng xing wai ke za zhi = Zhonghua zhengxing waike zazhi = Chinese journal of plastic surgery 12/2007; 23(6):476-9.
-
[show abstract]
[hide abstract]
ABSTRACT: To introduce a new technique of 1-stage reconstruction for thumb loss complicated by thumb-index web space contracture and to report its clinical effectiveness.
From November 1994 to September 2004 there were 11 patients with thumb loss and contracture in the thumb-index web space who had a combined transplantation of free tissues to reconstruct the missing thumb and to rebuild the web space. The reconstructive procedure used the second toe and the anterolateral thigh flap in 5 patients, the second toe and the scapular flap in 2, the big toe wraparound flap and the anterolateral thigh flap in 3, and the big toe wrapround flap and the scapular flap in 1. The 2 independent free tissues were connected together by a vascular combination to form an assembly with 1 common vascular pedicle, which then was anastomosed to the selected vessels in the recipient hand. In this vascular series the dorsalis pedis artery and the greater saphenous vein served as the common vascular pedicle of the flap transfers and the radial artery and the cephalic vein provided the recipient vessels. The outcomes of the reconstructions were evaluated using the Michigan Hand Outcomes Questionnaire.
The flaps survived completely in all patients except 1. In this patient a small area in the distal part of the transplanted anterolateral thigh flap became necrotic but healed after dressing changes without the need for further surgical intervention. A mean follow-up period of 3.6 years showed a mean increase of 4.3 cm in the width of the thumb-index web space and a considerable improvement in overall hand function was noted on the Michigan Hand Outcomes Questionnaire with effect sizes of greater than 3 (large effect) in all domains.
Combined transplantation of the second toe or the big toe wraparound flap and a free skin flap is suitable to reconstruct a missing thumb and repair the associated skin defect in the adjacent thumb-index web space. We found good functional recovery and an acceptable appearance in this series of patients. Type of study/level of evidence: Therapeutic, Level IV.
Therapeutic, Level IV.
The Journal Of Hand Surgery 03/2006; 31(2):236-41. · 1.35 Impact Factor
