Cartilage Transplantation Research Articles

Transplantation of Tissue-Engineered Cartilage in an Animal Model (Xenograft and Autograft): Construct Validation.

Tissue engineering holds great promise for cartilage repair with minimal donor-site morbidity. The in vivo maturation of a tissue-engineered construct can be tested in the subcutaneous tissues of the same species for autografts or of immunocompromised animals for allografts or xenografts. This section describes detailed protocols for the surgical transplantation of a tissue-engineered construct into an animal model to assess construct validity.

(iv) Treatment options for articular cartilage damage in the knee

Chondral damage within the knee of young patients remains a challenge to orthopaedic surgeons, with the chance of resulting mechanical symptoms limiting activity and the risk of progression to osteoarthritis. There are a number of different treatment options which utilize one of two principles for filling chondral defects: either bone marrow stimulation leading to fibrocartilaginous repair or transplantation of mature hyaline cartilage into the defect. In this article we review the current treatment options for symptomatic chondral damage within the knee, discussing the basic science, techniques involved and the evidence supporting each method.

3 Tesla high-resolution and delayed gadolinium enhanced MR imaging of cartilage (dGEMRIC) after autologous chondrocyte transplantation in the hip.

To evaluate the feasibility of 3 Tesla (T) high-resolution and gadolinium enhanced MRI of cartilage (dGEMRIC) in the thin and rounded hip cartilage of patients after acetabular matrix-based autologous chondrocyte transplantation (MACT). Under general ethics approval, 24 patients were prospectively examined 6-31 months after acetabular MACT at 3T using high-resolution proton-density weighted (PDw) images (bilateral PD SPACE, 0.8 mm isotropic; unilateral PD-TSE coronal/sagittal, 0.8 × 0.8 resp. 0.5 × 0.5 × 2.5 mm) as well as T1 mapping (3D-FLASH, 0.78 mm isotropic) in dGEMRIC technique, and clinically scored. The cartilage transplant was evaluated using an adapted MOCART score (maximum 85 points). T1 relaxation times were measured independently by two radiologists. Here, regions of interest were placed manually in automatically calculated relaxation-maps, both in the transplant and adjacent healthy cartilage regions. Interobserver reliability was estimated by means of intraclass-correlation (ICC). The transplant was morphologically definable in the PDw images of 23 patients with a mean MOCART score of 69 points (60-80 points, SD 6.5). T1 maps showed a clear differentiation between acetabular and femoral cartilage, but correlation with PDw images was necessary to identify the transplant. Mean T1 relaxation times of the transplant were 616.3 ms (observer 1) resp. 610.1 ms (observer 2), and of adjacent healthy acetabular cartilage 574.5 ms (observer 1) resp. 604.9 ms (observer 2). Interobserver reliability of the relaxation times in the transplant was excellent (ICC-coefficient 0.88) and in adjacent healthy regions good (0.77). High-resolution PDw imaging with adapted MOCART scoring and dGEMRIC is feasible after MACT in the thin and rounded hip cartilage.

Serial reconstruction of anophthalmic orbits with ‘bag-shaped’ flaps

The author's goal was to present an approach for serial surgical reconstruction of anophthalmic orbits with 'bag-shaped' flaps and cartilage transplantation. A review was performed of 53 patients who underwent serial physiological orbital reconstruction between 2006 and 2013. Orbital reconstruction was performed serially in stages, including "bag-shaped" flap transplantation, medial and lateral canthoplasty, tarsus reconstruction, and improvement of the strength of the levator palpebrae superior muscles. Curative effects were evaluated by the surgeons and patients jointly. Among the total of 53 cases, the curative effects were assessed as excellent in 28 patients, good in 17 patients, moderate in 6 patients, and poor in 2 patients. Two cases suffered necrosis of the bag-shaped flap, which was remedied with a frontal island flap and skin grafting; 4 cases experienced shallowness of the lower fornix, of which three were remedied by deepening of the lower fornix and the other by lower eyelid suspension. The appearance of the reconstructed eye socket was acceptable, natural and persistent. This procedure offers staged and serial reconstruction of anophthalmic orbits, according to the orbital shape and the volume loss of the orbital soft tissue. It is an ideal approach to reconstruct eye sockets, with a high survival rate of the flaps, acceptable appearance of the reconstructed eye socket, and stable depth of the upper and lower eyelid fornices.

Tips & tricks--collar button technique: safe and patient friendly myringoplasty technique

Background: The inlay cartilage butterfly myringoplasty is a simple technique with few complications for closure of tympanic membrane defects introduced by Eavey 1998, but still not often used. Its advantages consist in avoiding of exposure the tympanic cavity and possible blunting, option to operate both ears at once, safe local anaesthesia, reduction of operation time and cost, minimal postoperative care and patient comfort. Patients and Methods: We operated 10 patients using a to date not described simple cartilage transplant without perichondrium. Reason, localisation, extent and duration of the defect as well as complications, patient assessment and pure tone audiogram were analysed. Results: All defects were closed six months postoperative. Seven patients rated hearing as improved, two as non-changed and one patient showed deafness in the pure tone audiogram pre- and postoperative. The average air-bone gap of the thresholds at frequencies 0.5, 1, 2 and 3 kHz was 8.6 dB postoperative as compared to 16.3 dB preoperative. It could be shown that pure cartilage transplants without perichondrium used for defects up to 6mm in diameter were enwrapped by the tympanic membrane and covered by capillaries. Conclusion: The inlay cartilage butterfly myringoplasty is a safe and gentle technique for tympanic membrane defect closure.

AB0092 Controlled Expression of Endogenous Interleukin-4 for Gene Therapeutic Approaches towards Rheumatic Disorders

BackgroundRheumatic diseases such as osteoarthritis (OA) and rheumatoid arthritis (RA) rank among the most common musculoskeletal disorders around the globe accounting for marked loss of life quality, considerable disabilities and...

Experimental study of tissue-engineered cartilage allograft with RNAi chondrocytes in vivo.

PurposeTo determine the effects of RNA interference (RNAi) on chondrocyte proliferation, function, and immunological rejection after allogenic tissue-engineered cartilage transplantation within bone matrix gelatin scaffolds.MethodsSeven million rat normal and RNAi chondrocytes were harvested and separately composited with fibrin glue to make the cell suspension, and then transplanted subcutaneously into the back of Sprague Dawley rats after being cultured for 10 days in vitro. Untransplanted animals served as the control group. The allograft and immunological response were examined at 1, 2, 4, 8, and 12 months postoperatively with hematoxylin and eosin histochemical staining, immunohistochemical staining (aggrecan, type II collagen, class I and II major histocompatibility complex), and flow cytometry for peripheral blood cluster of differentiation 4+ (CD4+) and CD8+ T-cells.ResultsThere was no infection or death in the rats except one, which died in the first week. Compared to the control group, the RNAi group had fewer eukomonocytes infiltrated, which were only distributed around the graft. The ratio of CD4+/CD8+ T-cells in the RNAi group was significantly lower than the normal one (P<0.05). There were many more positively stained chondrocytes and positively stained areas around the cells in the RNAi group, which were not found in the control group.ConclusionThe aggrecanase-1 and aggrecanase-2 RNAi for chondrocytes decreased the immunological rejection effect.

The quality of healing: articular cartilage.

Articular cartilage lacks an intrinsic capacity for self-repair, and once damaged, it never heals. This creates an opportunity for surgical intervention, whether to stimulate a healing response that results in the formation of a lower-quality fibrocartilaginous scar or formal cartilage repair in the form of cartilage transplants. This article will review the nature of cartilage injury and discuss indications and techniques for repair.

Direct Expansion of Chondrocytes in a Dynamic Three‐Dimensional Culture System: Overcoming Dedifferentiation Effects in Monolayer Culture

Maintenance of the chondrocyte phenotype during cell culture to successful transplantation of cartilage is highly challenging. However, the question of the optimal method of isolation and expansion of chondrocytes for tissue engineering has not previously been investigated in detail. The present study investigates the possibility of improved in vitro maturation of chondrocytes through a method of cell duplication that does not subject chondrocytes to dedifferentiation. The culture chamber of the bioreactor was designed with an internal geometry that mimicked that of a ball-and-socket joint. The shear stresses exerted on the surface of the bioreactor chamber wall by a peristaltic pump operating at flow rates of 2 mL/min were simulated by computational fluid dynamics (CFD) modeling. Small pieces (5 mm) of calf nasal septum cartilage were prepared and exposed to trypsin and 0.2% collagenase type II in Dulbecco's modified Eagle's medium (DMEM), which was then replaced with unsupplemented DMEM. The cells were harvested and then immediately seeded into alginate scaffolds. All cell-seeded scaffolds were cultured for 3-5 days in flasks, then transferred to the bioreactor and dynamically cultured for 3-5 days under direct perfusion with 2 mL/min DMEM. After culture in the bioreactor, all cell-seeded scaffolds were fixed in Bouin fixative, dehydrated, cleared, and then embedded in paraffin wax. Sections of 5-7 μm were cut and stained with several histochemical staining methods. The results of CFD modeling indicated peak velocity and maximum wall shear stress were 3.406 × 10(-3) m/s and 0.0482 dyn/cm(2) (1 Pa = 10 dyn/cm(2) ), respectively. Histological examination of chondrocytes cultured in the bioreactor revealed evidence of cartilage-like tissue with lacuna and chondron formation. The cartilage-like matrix had accumulated within the lumen of clusters of round mature chondrocytes, with the cells surrounding the metachromatic territorial matrix-staining strongly with toluidine blue. Sections stained with the hematoxylin/safranin O/fast green and Alcian blue/nuclear fast red methods show sulfated glycosaminoglycans in the matrix (produced by the chondrocytes) as intense red and blue, respectively. The findings of the present study indicate that incubation in DMEM supplemented with enzymes followed by explant isolation and culture in a bioreactor is the optimal method for the direct expansion of chondrocytes for cartilage tissue engineering.

You Can Do Arthroplasty in a Young Patient, But…

You Can Do Arthroplasty in a Young Patient, But…

One-Step Surgery With Multipotent Stem Cells for the Treatment of Large Full-Thickness Chondral Defects of the Knee

Background: Chondral lesions in athletically active patients cause considerable morbidity, and treatment with existing cell-based therapies can be challenging. Bone marrow has been shown as a possible source of multipotent stem cells (MSCs) with chondrogenic potential and is easy to harvest during the same surgical procedure. Purpose: To investigate the clinical outcome in a group of active patients with large full-thickness chondral defects of the knee treated with 1-step surgery using bone marrow–derived MSCs and a second-generation matrix. Study Design: Case series; Level of evidence, 4. Methods: From January 2007 to February 2010, 25 patients (average age, 46.5 years) with symptomatic large chondral defects of the knee (International Cartilage Repair Society grade 4) who underwent cartilage transplantation with MSCs and a collagen type I/III matrix were followed up for a minimum of 3 years. The average lesion size was 8.3 cm2. Coexisting injuries were treated during the same surgical procedure in 18 patients. All patients underwent a standard postoperative rehabilitation program. Preoperative and postoperative evaluations at 1-year, 2-year, and final follow-up included radiographs, magnetic resonance imaging (MRI), and visual analog scale (VAS) for pain, International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm, Marx, and Tegner scores. Seven patients underwent second-look arthroscopic surgery, with 4 consenting to a tissue biopsy. Results: No patients were lost at final follow-up. The average preoperative values for the evaluated scores were significantly improved at final follow-up (P < .001): VAS, 5.4 ± 0.37 to 0.48 ± 0.19; IKDC subjective, 37.92 ± 4.52 to 81.73 ± 2.42; KOOS pain, 61.04 ± 3.95 to 93.32 ± 1.92; KOOS symptoms, 55.64 ± 3.23 to 89.32 ± 2.32; KOOS activities of daily living, 63.96 ± 4.48 to 91.20 ± 2.74; KOOS sports, 34.20 ± 5.04 to 80.00 ± 3.92; KOOS quality of life, 32.20 ± 4.43 to 83.04 ± 3.37; Lysholm, 46.36 ± 2.25 to 86.52 ± 2.73; Marx, 3.00 ± 0.79 to 9.04 ± 0.79; and Tegner, 2.12 ± 0.32 to 5.64 ± 0.26. Patients younger than 45 years of age and those with smaller or single lesions showed better outcomes. The MRI scans showed good stability of the implant and complete filling of the defect in 80% of patients, and hyaline-like cartilage was found in the histological analysis of the biopsied tissue. No adverse reactions or postoperative complications were noted. Conclusion: The treatment of large chondral defects with MSCs is an effective procedure and can be performed routinely in clinical practice. Moreover, it can be achieved with 1-step surgery, avoiding a previous surgical procedure to harvest cartilage and subsequent chondrocyte cultivation.

Revision cartilage cell transplantation for failed autologous chondrocyte transplantation in chronic osteochondral defects of the knee

The management of failed autologous chondrocyte implantation (ACI) and matrix-assisted autologous chondrocyte implantation (MACI) for the treatment of symptomatic osteochondral defects in the knee represents a major challenge. Patients are young, active and usually unsuitable for prosthetic replacement. This study reports the results in patients who underwent revision cartilage transplantation of their original ACI/MACI graft for clinical or graft-related failure. We assessed 22 patients (12 men and 10 women) with a mean age of 37.4 years (18 to 48) at a mean of 5.4 years (1.3 to 10.9). The mean period between primary and revision grafting was 46.1 months (7 to 89). The mean defect size was 446.6 mm(2) (150 to 875) and they were located on 11 medial and two lateral femoral condyles, eight patellae and one trochlea. The mean modified Cincinnati knee score improved from 40.5 (16 to 77) pre-operatively to 64.9 (8 to 94) at their most recent review (p < 0.001). The visual analogue pain score improved from 6.1 (3 to 9) to 4.7 (0 to 10) (p = 0.042). A total of 14 patients (63%) reported an 'excellent' (n = 6) or 'good' (n = 8) clinical outcome, 5 'fair' and one 'poor' outcome. Two patients underwent patellofemoral joint replacement. This study demonstrates that revision cartilage transplantation after primary ACI and MACI can yield acceptable functional results and continue to preserve the joint.

Surgical management of nasal alar rim and valve collapse

Introduction Nasal valve collapse can provoke sleep-related breathing disorders in adults. Congenital and acquired alar rim collapse necessitates surgical treatment. The purpose of the present communication is to share our experience with the procedures for reconstruction of the external nasal valve after septoplasty on the occasion of nasal septal deviation, reconstruction and rhinoplasty. Materials and methods During the period from 2000 till 2010, we treated 33 patients with bilateral alar rim collapse and 4 patients with unilateral one. Fifteen patients presented with a congenital pathology. Rhinoplasty was previously performed in 18 patients but septoplasty in four ones. There were nasal septum deformities in 32 patients. The following surgical techniques were applied: lateral rhinopexy, autologous cartilage transplantation, modified lateral rhinopexy, fixation of the cranial end of alar cartilage to the caudal end of triangular cartilages, and suturing techniques as well. In two cases, percutaneous fixation of the alar rims was carried out. Results The immediate postoperative results were satisfactory. A better aesthetics and an improved breathing function could be achieved in all the patients. The comparative evaluation of the surgical techniques identified the advantages of the external rhinoplasty approach, lateral rhinopexy, cartilage transplantation and suturing techniques. However, there patients complained of relapse two months after operation. Conclusion Based on our experience and the data from the world literature available the conclusion can be drawn that nasal valve and alar rim collapse represent a serious challenge for contemporary rhinosurgery. An individualized surgical approach to the single patients is obligatory. The aggressive surgical methods seem to be more effective. Acknowledgements P. Nedev M. Milkov R. Benchev D. Vicheva.

Treatment of a Patellar Chondral Defect Using Juvenile Articular Cartilage Allograft Implantation

Focal articular cartilage defects of the knee commonly occur. Various arthroscopic and open procedures have been developed to address these lesions when they are symptomatic, all aimed at defect filling. Juvenile cartilage transplantation procedures have recently been described as an option for managing symptomatic cartilage lesions. We present a technique using transfer of juvenile cartilage allograft transplantation into the defect with subsequent second-look arthroscopy and biopsy results after implantation.

Funktionelle und ästhetische Rehabilitation der Mikrotie bei Kindern und Jugendlichen

Microtia leads to a severe functional and aesthetic handicap. Traditionally, the auricle is often reconstructed with cartilage transplants, which is, however, associated with some partially substantial disadvantages. The authors have instead used implants of porous polyethylene for successful ear reconstruction for years, thus, avoiding some of these disadvantages. A significant benefit for the patient is achieved by simultaneous hearing rehabilitation by the implantation of active middle ear prostheses. The authors present their surgical concept which allows functional and aesthetic rehabilitation of microtia in children and adolescents in a single operation. In the respective patient collective, audiometric measurements in quiet and noisy environments were conducted pre- and postoperatively, and health-related quality of life was determined using a validated questionnaire. All patients experienced a substantial hearing gain both in quiet and noisy environments. The evaluation of health-related quality of life showed a significant benefit from the intervention. Functional and aesthetic rehabilitation of microtia with active middle ear implants and ear reconstruction using porous polyethylene leads to good and reliable long-term results and can increase the health-related quality of life of affected children and adolescents. The main advantage of this concept is the possibility of a single procedure.

Influence of cryopreservation, cultivation time and patient’s age on gene expression in Hyalograft® C cartilage transplants

Our aim was to evaluate the impact of cryopreservation, cultivation time and patient's age on the expression of specific chondrogenic markers in Hyalograft® C transplants. Gene expression of chondrocyte markers [collagen type I (COL1A1), COL2A1, aggrecan, versican, melanoma inhibitory activity (MIA) and interleukin (IL)-1β] was analysed in cartilage biopsies (n = 17) and Hyalograft® C transplant samples (non-cryopreserved = 78, cryopreserved = 13) by quantitative real-time polymerase chain reaction (PCR). Correlation analyses were performed to evaluate the influence of the above-named parameters on the level of gene expression. Cryopreservation of cells was found to decrease COL2A1 and MIA significantly (4.6-fold, p < 0.01 and 2-fold, p < 0.045, respectively). The duration of cryopreservation had no further influence on the expression of these factors. No correlation was detected between cultivation time (75 ± 31 days) and the expression level of any gene. Cartilage transplants from older patients (>35 years) exhibited a significantly higher IL-1β expression (3.7-fold, p < 0.039) than transplants from younger patients (≤ 35 years). Our data demonstrate that cryopreservation has a profound impact on chondrocyte metabolic activity by decreasing the expression of COL2A1 and MIA in Hyalograft® C transplants, independent of the duration of cryopreservation.

Is the Transplant Quality at the Time of Surgery Adequate for Matrix-guided Autologous Cartilage Transplantation? A Pilot Study

Matrix-guided autologous chondrocyte transplantation (MACT) has been proposed as an option for treating large full-thickness cartilage defects. However, little is known about the chondrogenic potential of transplants for MACT at the time of implantation, although cell quality and chondrogenic differentiation of the implants are crucial for restoration of function after MACT. We therefore asked: (1) Do MACT implants allow deposition of extracellular cartilage matrix in an in vitro culture model? (2) Are these implants associated with improved knee function 1 year after MACT in large cartilage defects? We retrospectively reviewed all 125 patients with large localized cartilage defects (mean defect size 5 cm(2)) of the knee who were treated with MACT from 2005 to 2010. The mean age was 31 years (range, 16-53 years). Portions of the cell-matrix constructs (n = 50) that were not implanted in the cartilage defects were further cultured and tested for their potential to form articular cartilage. Knee function of all patients was analyzed preoperatively, 3 months, and 1 year postoperatively with the International Knee Documentation Committee (IKDC) score. In vitro assessment of the cell-matrix implants showed chondrogenic differentiation with positive staining for glycosaminoglycans and collagen II in all cultures. Enzyme-linked immunosorbent assay showed an increase of collagen II production. We observed an improvement in median IKDC score from 41 to 67 points at last followup. Cartilage extracellular matrix deposition shows adequate implant quality for MACT at the time of implantation and justifies the use for treatment of large cartilage defects.

Exposure of the Medial Talar Dome

Open surgical exposure of the medial aspect of the talus is primarily indicated for osteochondral lesions of the talus and talar body fractures. Secondary to the difficulty of access, a variety of techniques have been described. The surgical techniques described in the literature include transmalleolar access windows, medial and anterior tibial osteotomies, and resection osteotomies (plafondoplasty). The purpose of this article is to describe the surgical technique for the bi-planar chevron osteotomy of the medial malleolus. This osteotomy can provide full exposure to the entire medial aspect of the talus. The orientation of the osteotomy allows for perpendicular placement of instrumentation on the medial half of the talus and is particularly useful for cartilage transplant procedures. The technique is reproducible and has a low complication rate when performed correctly.

The Application of Tissue Engineering Cartilage and Bracket Constructed Biomaterials for Athletic Injury

The development of tissue engineering techniques for cartilage repair and regeneration provided a new way, according to their own characteristics and structure of the cartilage, as artificial cartilage replacement materials and scaffold materials should have good biomechanical properties. The effect of autologous cartilage transplantation is best in the field of articular cartilage repair, the study of bone marrow stromal cells in vitro tests and animal experiments was more, and the clinical application was less, which is still in the stage of exploration. Biomaterials material for tissue repair plays a more and more important role, especially in athletic injury.

Chondrogenesis of myoblasts in biodegradable poly-lactide-co-glycolide scaffolds

Myoblasts are considered to be an alternative cell source for cell-based meniscal repair due to their multiple differentiation potentials. This study addresses the chondrogenic differentiation of myoblasts seeded into poly-lactide-co-glycolide (PLGA) scaffolds following implantation in a subcutaneous pocket of nude mice. Canine myoblasts isolated from a Beagle were expanded and seeded into PLGA scaffolds and cultured in cartilage-derived morphogenetic protein-2 (CDMP-2) and transforming growth factor-β1(TGF-β1)-containing medium for 2weeks invitro. The constructs were implanted into a subcutaneous pocket of 24combined immunodeficiency mice and harvested after 8 and 12weeks, respectively. Hematoxylin and eosin staining of the sections of the engineered cartilage at 8 and 12weeks revealed the regeneration of fibrocartilage. Immunohistochemical staining confirmed a similar distribution of collagen typeⅡ in the engineered cartilage as the normal meniscus. At 12weeks, expression of mRNAs for typeⅠ collagen, typeⅡ collagen and aggrecan was detected by RT-PCR. The compressive moduli of engineered cartilage reached 85.72% of the normal meniscus at 12weeks, with a high level of glycosaminoglycan(GAG) content (no statistical difference from normal). Myoblast-seeded PLGA scaffolds express a stable chondrogenic phenotype in a heterotopic model of cartilage transplantation and represent a suitable tool for tissue engineering of cartilage.