Full-thickness Articular Cartilage Research Articles

Comparison of MRI Osteoarthritis Knee Score with Clinico-Radiological Grading

Abstract Background Knee joint osteoarthritis (OA) is among the most prevalent degenerative diseases of the joints in the body. Various scoring system exists for grading OA, such as (1) magnetic resonance imaging (MRI) Osteoarthritis Knee Score (MOAKS), (2) clinical grading by Western Ontario and McMaster Universities Arthritis Index (WOMAC), and (3) X-ray grading of the Kellgren–Lawrence grading system (K-L). Objectives To study MRI findings and MOAKS scoring of knee OA and correlation with WOMAC and K-L scoring. Setting and Design Cross-sectional study in hospital population. Methods and Material A total 40 knee OA cases underwent an MRI of the knee. MOAKS scoring was done and compared with K-L grading and WOMAC scores. Statistical Analysis Collected data were compiled systematically and interpreted using IBM SPSS statistics software 25.0. A p-value of less than 0.05 was considered significant. Results The mean total WOMAC score was 9. K-L grade 2 was the most prevalent X-ray grade. Bone marrow lesion (BML) and cartilage loss in MOAKS score were greater in the medial femorotibial region. A moderate positive correlation was noted between the WOMAC score and K-L grade; full-thickness articular cartilage loss score at the medial femorotibial joint (MFTJ) and WOMAC score; partial-thickness articular cartilage loss score at lateral femorotibial joint (LFTJ) and WOMAC total pain score. No correlation was found between BML and pain severity score. Conclusion Higher WOMAC scores were associated with higher grades of K-L scoring and score of cartilage loss (partial and full thickness) of the MOAKS scoring system. The rest of the features of the MOAKS score (BML score, osteophyte, and synovitis) had no significant association with pain severity and K-L grading.

Catalpol promotes articular cartilage repair by enhancing the recruitment of endogenous mesenchymal stem cells.

Articular cartilage defect is challenged by insufficient regenerative ability of cartilage. Catalpol (CA), the primary active component of Rehmanniae Radix, could exert protective effects against various diseases. However, the impact of CA on the treatment of articular cartilage injuries is still unclear. In this study, full-thickness articular cartilage defect was induced in a mouse model via surgery. The animals were intraperitoneally injected with CA for 4 or 8 weeks. According to the results of macroscopic observation, micro-computed tomography CT (μCT), histological and immunohistochemistry staining, CA treatment could promote mouse cartilage repair, resulting in cartilage regeneration, bone structure improvement and matrix anabolism. Specifically, an increase in the expression of CD90, the marker of mesenchymal stem cells (MSCs), in the cartilage was observed. In addition, we evaluated the migratory and chondrogenic effects of CA on MSCs. Different concentration of CA was added to C3H10 T1/2 cells. The results showed that CA enhanced cell migration and chondrogenesis without affecting proliferation. Collectively, our findings indicate that CA may be effective for the treatment of cartilage defects via stimulation of endogenous MSCs.

All-Arthroscopic Matrix-Associated Autologous Chondrocyte Implantation for a Trochlear Defect

Matrix-associated autologous chondrocyte implantation (MACI) is a 2-step technique designed to treat symptomatic full-thickness articular cartilage defects of the knee. In this technique article, MACI (autologous cultured chondrocytes on porcine collagen membrane) is used to treat a femoral trochlear defect of the knee. Treating a defect with this technique leads to improved clinical outcomes by restoring the native chondral surface architecture and biomechanics of the knee. In addition, it has the potential to prevent or delay further progressive degeneration of the joint. It is a 2-stage procedure consisting of an initial arthroscopic cartilage biopsy, followed by 4 to 6 weeks of in vitro chondrocyte expansion and, finally, re-implantation. We recommend performing the MACI procedure arthroscopically for the second stage to treat a femoral trochlear defect. During the second surgical procedure, we examine and prepare the recipient site, followed by graft introduction in an all-arthroscopic manner via dry scoping, secured by a thin layer of fibrin glue.

Combination of a human articular cartilage-derived extracellular matrix scaffold and microfracture techniques for cartilage regeneration: A proof of concept in a sheep model

BackgroundThe utilization of decellularized extracellular matrix has gained considerable attention across numerous areas in regenerative research. Of particular interest is the human articular cartilage-derived extracellular matrix (hACECM), which presents as a promising facilitator for cartilage regeneration. Concurrently, the microfracture (MF) ​technique, a well-established marrow stimulation method, has proven efficacious in the repair of cartilage defects. However, as of the current literature review, no investigations have explored the potential of a combined application of hACECM and the microfracture technique in the repair of cartilage defects within a sheep model. HypothesisThe combination of hACECM scaffold and microfracture will result in improved repair of full-thickness femoral condyle articular cartilage defects compared to the use of either technique alone. Study designControlled laboratory study. MethodsFull-thickness femoral condyle articular cartilage defect (diameter, 7.0 ​mm; debrided down to the subchondral bone plate) were created in the weight-bearing area of the femoral medial and lateral condyles (n ​= ​24). All of defected sheep were randomly divided into four groups: control, microfracture, hACECM scaffold, and hACECM scaffold ​+ ​microfracture. After 3, 6 and 12 months, the chondral repair was assessed for standardized (semi-) quantitative macroscopic, imaging, histological, immunohistochemical, mechanics, and biochemical analyses in each group. ResultAt 3, 6 and 12 months after implantation, the gross view and pathological staining of regenerative tissues were better in the hACECM scaffold and hACECM scaffold ​+ ​microfracture groups than in the microfracture and control groups; Micro-CT result showed that the parameters about the calcified layer of cartilage and subchondral bone were better in the hACECM scaffold and hACECM scaffold ​+ ​microfracture groups than the others, and excessive subchondral bone proliferation in the microfracture group. The results demonstrate that human cartilage extracellular matrix scaffold alone is an efficient, safe and simple way to repair cartilage defects. ConclusionhACECM scaffolds combined with/without microfracture facilitate chondral defect repair. The translational potential of this articlePreclinical large animal models represent an important adjunct and surrogate for studies on articular cartilage repair, while the sheep stifle joint reflects many key features of the human knee and are therefore optimal experimental model for future clinical application in human. In this study, we developed a human articular cartilage-derived extracellular matrix scaffold and to verify the viability of its use in sheep animal models. Clinical studies are warranted to further quantify the effects of hACECM scaffolds in similar settings.

Tissue adhesive, ROS scavenging and injectable PRP-based 'plasticine' for promoting cartilage repair.

Platelet-rich plasma (PRP) that has various growth factors has been used clinically in cartilage repair. However, the short residence time and release time at the injury site limit its therapeutic effect. The present study fabricated a granular hydrogel that was assembled from gelatin microspheres and tannic acid through their abundant hydrogen bonding. Gelatin microspheres with the gelatin concentration of 10 wt% and the diameter distribution of 1-10 μm were used to assemble by tannic acid to form the granular hydrogel, which exhibited elasticity under low shear strain, but flowability under higher shear strain. The viscosity decreased with the increase in shear rate. Meanwhile, the granular hydrogel exhibited self-healing feature during rheology test. Thus, granular hydrogel carrying PRP not only exhibited well-performed injectability but also performed like a 'plasticine' that possessed good plasticity. The granular hydrogel showed tissue adhesion ability and reactive oxygen species scavenging ability. Granular hydrogel carrying PRP transplanted to full-thickness articular cartilage defects could integrate well with native cartilage, resulting in newly formed cartilage articular fully filled in defects and well-integrated with the native cartilage and subchondral bone. The unique features of the present granular hydrogel, including injectability, plasticity, porous structure, tissue adhesion and reactive oxygen species scavenging provided an ideal PRP carrier toward cartilage tissue engineering.

Construction of ultrasonically treated collagen/silk fibroin composite scaffolds to induce cartilage regeneration

A novel tissue-specific functional tissue engineering scaffold for cartilage repair should have a three-dimensional structure, good biosafety and biological activity, and should be able to promote cartilage tissue regeneration. This study aimed to determine the effect of ultrasound-treated collagen/silk fibroin (Col/SF) composite scaffolds with good mechanical properties and high biological activity on cartilage repair. The characteristics of the scaffolds with different Col/SF ratios (7:3, 8:2, and 9:1) were determined by scanning electron microscopy, Fourier-transform infrared spectroscopy, and porosity, water absorption, and compression tests. In vitro evaluations revealed the biocompatibility of the Col/SF scaffolds. Results suggested that the optimal ratio of Col/SF composite scaffolds was 7:3. The Col/SF scaffolds induced adipose-derived stem cells to undergo chondrogenic differentiation under chondrogenic culture conditions. The efficiency of Col/SF scaffolds for cartilage regeneration applications was further evaluated using an in vivo model of full-thickness articular cartilage defects in New Zealand rabbits. The Col/SF scaffolds effectively promoted osteochondral regeneration as evidenced by macroscopic, histological, and immunohistochemical evaluation. The study demonstrates that ultrasound-treated Col/SF scaffolds show great potential for repairing cartilage defects.

Repair of full-thickness articular cartilage defects with a 3DP-anchored three-phase complex

IntroductionTo repair cartilage defect as well as the calcified cartilage layer (CCL) and bone tissue, there is need to fabricate a three-phase complex that mimics the natural cartilage tissue. Materials and methodsSF/Col-Ⅱ/HA scaffolds were constructed by low-temperature 3D printing, and to prepare a three-phase complex. The microstructure were showed using a SEM image analysis program. To observe collagen and glycosaminoglycan expression and analyze morphometric parameters, HE staining was performed to reveal new cartilage. Immunohistochemical were performed to investigate the collagen content and defect repair status in the new cartilage group in vitro and vivo. ResultsPhysical and biochemical properties and biocompatibility of three-phase complex met the requirements of constructing tissue-engineered cartilage. The OD values increased gradually at different time points. With increasing culture time, the OD values showed an upward trend. The HE and immunohistochemical staining results showed that new cartilage had formed at the defect and new cartilage formation occurred during in vivo repair. Conclusion3DP-anchored three-phase complexes have good physical and biochemical properties and biocompatibility and thus represent an alternative cartilage tissue engineering material.

Outcomes after Bipolar Osteochondral Allograft Transplantation in the Ankle

Category: Ankle Arthritis; Ankle Introduction/Purpose: Surgical treatment options for symptomatic, full-thickness articular cartilage loss in the ankle are not consistently effective in restoring ankle function. Osteochondral allograft transplantation provides a standard-of-care alternative for patients, however, outcomes reported to date have been only fair, with a high incidence of reoperation and revision. However, recent cartilage storage and preservation techniques have significantly improved the percent viable chondrocytes at the time of implantation in OCAs. These high-chondrocyte-viability allografts should lead to improved survivability of OCAs and improved outcome measures. This study aimed to document the initial outcomes for patients undergoing bipolar OCA transplantation in the ankle after advances in tissue preservation, transplantation techniques, and patient management strategies. Methods: Patients with symptomatic tibiotalar arthritis were prospectively enrolled into a registry designed to follow outcomes after OCA surgeries in the ankle. All patients underwent complete OCA replacement of their tibial plafond and talar dome, with most undergoing fibular articular resurfacing. All OCA were size and side matched and preserved in Missouri Osteochondral Allograft Preservation System (MOPS). Patients followed a standardized, procedure-specific rehabilitation protocol after surgery, including remaining non-weight bearing for 8 weeks, weekly therapy visits, limited step count during recovery, and avoidance of high impact activities until 1 year after surgery. Patients followed-up with their physician at regular post-operative timepoints. Radiographs and patient reported outcome measures (VAS, AAOS Foot and Ankle, PROMIS PF, PROMIS Mobility) were obtained at each follow-up visit. Demographic and operative data were collected from the electronic medical record. All reported complications, reoperations, revisions, and failures were recorded in the EMR. Results: 14 patients were included for analyses with 12 undergoing primary OCA transplantation, and 2 undergoing revision OCA transplantation. Mean age and follow up was 36 and 44.1 months, respectively. All patients underwent tibia and talus OCA transplantation, with 10/14 including a fibula OCA transplantation. Initial success was 92.9% with one documented failure (tibial OCA collapse). Radiographic assessments indicated OCA integration and maintenance of joint space in 12 patients (85.7%). AAOS and VAS pain scores improved significantly from preoperative measures at each timepoint (p=.002, p=.03), while postoperative improvements in PROMIS Mobility and PROMIS Physical Function scores did not reach significance (p>0.15) (Table 1). Patients that were non-adherent to postoperative restriction and rehabilitation protocols, all 1-year postoperative PROs were significantly lower than for patients who were adherent. Conclusion: Ankle osteoarthritis in young patients continues to present a challenging dilemma. Previous attempts at large bipolar OCAs in the ankle have yielded fair, to poor, results. However, recent advances in bulk osteochondral allograft preservation has improved chondrocyte viability. Based on the results of our study, the use of high-chondrocyte-viability allografts for OCA transplantation is a viable option for the treatment of symptomatic bipolar osteochondral defects in the ankle joint. However, post operative rehab protocols are equally important in determining outcomes, and patient selection and education is key to ensuring successful outcomes. Longer term follow up is ongoing.

Construction of 3D-Bioprinted cartilage-mimicking substitute based on photo-crosslinkable Wharton's jelly bioinks for full-thickness articular cartilage defect repair.

Three-dimensional (3D) bioprinted cartilage-mimicking substitutes for full-thickness articular cartilage defect repair have emerged as alternatives to in situ defect repair models. However, there has been very limited breakthrough in cartilage regeneration based on 3D bioprinting owing to the lack of ideal bioinks with printability, biocompatibility, bioactivity, and suitable physicochemical properties. In contrast to animal-derived natural polymers or acellular matrices, human-derived Wharton's jelly is biocompatible and hypoimmunogenic with an abundant source. Although acellular Wharton's jelly can mimic the chondrogenic microenvironment, it remains challenging to prepare both printable and biologically active bioinks from this material. Here, we firstly prepared methacryloyl-modified acellular Wharton's jelly (AWJMA) using a previously established photo-crosslinking strategy. Subsequently, we combined methacryloyl-modified gelatin with AWJMA to obtain a hybrid hydrogel that exhibited both physicochemical properties and biological activities that were suitable for 3D bioprinting. Moreover, bone marrow mesenchymal stem cell-loaded 3D-bioprinted cartilage-mimicking substitutes had superior advantages for the survival, proliferation, spreading, and chondrogenic differentiation of bone marrow mesenchymal stem cells, which enabled satisfactory repair of a model of full-thickness articular cartilage defect in the rabbit knee joint. The current study provides a novel strategy based on 3D bioprinting of cartilage-mimicking substitutes for full-thickness articular cartilage defect repair.

Demonstration of the Medial Subvastus Knee Exposure for MACI Implantation

Background: There are several techniques for knee exposure in treating chondral defects with restorative procedures. The medial subvastus knee exposure is often overlooked when choosing the surgical approach. When properly performed, the medial subvastus approach can allow for the treatment of a wide range of pathology while preserving the extensor mechanism. Indications: We present a case of an active 40-year-old man with persistent left knee pain noted to have a full-thickness medial femoral condylar articular cartilage defect in an otherwise healthy appearing knee. Technique Description: The rationale and considerations for the medial subvastus knee exposure in treating a chondral defect with an autologous chondrocyte implant are discussed. Careful consideration of the approach, intra-articular exposure, and closure are emphasized to achieve optimal outcomes. Results: At 18 months postoperative, the patient reported no knee pain with improvements made in Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm, and International Knee Documentation Committee (IKDC) scores. These results are consistent with our institutions larger cohort of 26 patients undergoing matrix-induced autologous chondrocyte implantation (MACI) using the subvastus approach. These improvements in patient-reported outcomes are maintained at 2 years postoperative and are consistent with other published outcomes of the MACI procedure. Discussion/Conclusion: Excellent results in addressing chondral pathology about the knee can be achieved by selecting the appropriate surgical access. The subvastus approach has several advantages such as preserving the quadriceps mechanism, improving postoperative quadriceps muscle strength, conservation of the patellar genicular blood supply and possibly reducing postoperative pain that can result in a faster rehabilitation. When performed systematically and carefully, complete exposure of the knee can be achieved to facilitate a wide variety of surgical interventions. In patients undergoing cartilage restoration procedures, the medial subvastus approach should be considered in the surgeon’s armamentarium. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Evaluation of a modified subchondroplasty technique in an equine full-thickness cartilage defect model: a pilot study

To perform a pilot study with the intent of assessing the feasibility of a modified subchondroplasty (mSCP) technique in a validated preclinical equine model of full-thickness articular cartilage loss and evaluate the short-term patient response to the injected materials. 3 adult horses. Two 15-mm-diameter full-thickness cartilage defects were created on the medial trochlear ridge of each femur. Defects were treated with microfracture and then filled by 1 of 4 techniques: (1) autologous fibrin graft (FG) via subchondral injection of fibrin glue (FG), (2) autologous fibrin graft via direct injection of FG, (3) subchondral injection of a calcium phosphate bone substitute material (BSM) with direct injection of FG, and (4) untreated control. Horses were euthanized after 2 weeks. Patient response was evaluated via serial lameness examination, radiography, magnetic resonance imaging, computed tomography, gross evaluation, microcomputed tomography, and histopathology. All treatments were successfully administered. The injected material perfused through the underlying bone into the respective defects without adversely affecting the surrounding bone and articular cartilage. Increased new bone formation was seen at the margins of the trabecular spaces containing BSM. There was no treatment effect on the amount or composition of tissue within defects. The mSCP technique was a simple, well-tolerated technique in this equine articular cartilage defect model without significant adverse effects to host tissues after 2 weeks. Larger studies with long-term follow-ups are warranted.

Exploring the Mechanism of Microfracture in the Treatment of Porcine Full-Thickness Cartilage Defect

Background: Microfracture has the most extensive clinical application because of its advantages of a single operation, unified process, and low operation cost. Because research on the repair mechanism of microfractures in the treatment of cartilage defects is not in-depth, this study aimed to elucidate the mechanism. Purpose: To identify the characteristic cell subsets at different repair stages after microfracture, systematically analyze the repair process of the defect area after microfracture, and investigate the mechanism of fibrocartilage repair. Study Design: Descriptive laboratory study. Methods: Full-thickness articular cartilage defects and microfractures was established in the right knee of Bama miniature pigs. Single-cell transcriptional assays were used to identify the characteristics of cells isolated from healthy articular cartilage and regenerated tissues. Results: Microfractures induced mature fibrous repair in the full-thickness cartilage defect six months after surgery, while early stages of repair occurred within six weeks. Based on single-cell sequencing results, eight subsets and specific marker genes were identified. Two processes may occur after microfracture: normal hyaline cartilage regeneration and abnormal fibrocartilage repair. Regulatory chondrocytes, proliferative chondrocytes and cartilage progenitor cells (CPCs) may play important roles in the normal regeneration process. During abnormal repair, CPCs and skeletal stem cells may have different functions, and macrophages and endothelial cells may play important regulatory roles in the formation of fibrochondrocytes. Conclusions: Using single-cell transcriptome sequencing, this study investigated the tissue regeneration process and identified key cell subsets after microfracture. Clinical Relevance: These results provide future targets for optimizing the repair effect of microfracture.

Histopathological study of the effect of using repeated doses of platelets-rich plasma on articular cartilage repair in Rabbits

The present study was performed on platelet-rich plasma compound from animals engaged in this work, to be directly injected in the joint space of the affected stifle joint 5mm diameter full-thickness articular cartilage removal in the knee joint manually using the same instrument 5 mm drill to remove the cartilage, by different doses to evaluate its influence on articular cartilage repair. In this experiment, 28 adult rabbits were used. The same defect is created on the lateral condyle of the distal end of the femur. Three identical groups of animals were formed randomly. Group I was untreated. Group II was treated with a single dose of PRP (which was administered immediately after the creation of the defect), and group III was treated with two doses of PRP (the first dose was given immediately after the creation of the defect, and the second doses after 15 days of the first one. The histological examinations were recorded of four rabbits of each group, which were euthanized one and two months after treatment, and the assessment of cartilage tissue repair was checked. The control group showed destruction of articular cartilage at the site of the lesion with involvement of subchondral bone in both periods 30 and 60 days of examination, while specimens taken from groups II and III after 30 days showed a new tissue formation which is characterized as the homogenous extracellular matrix, with the proliferation of active chondrocytes. At the same time, slides on day 60 of treatment showed an increased number of newly formed chondrocytes and a clear line of demarcation between articular cartilage and subchondral bone, representing the tissue filling the gap had been created at the beginning of the experiment.

Direct Reprogramming of Mouse Subchondral Bone Osteoblasts into Chondrocyte-like Cells.

Treatment of full-thickness articular cartilage defects with exposure of subchondral bone often seen in osteoarthritic conditions has long been a great challenge, especially with a focus on the feasibility of in situ cartilage regeneration through minimally invasive procedures. Osteoblasts that situate in the subchondral bone plate may be considered a potentially vital endogenous source of cells for cartilage resurfacing through direct reprogramming into chondrocytes. Microarray-based gene expression profiles were generated to compare tissue-specific transcripts between subchondral bone and cartilage of mice and to assess age-dependent differences of chondrocytes as well. On osteoblast cell lines established from mouse proximal tibial subchondral bone, sequential screening by co-transduction of transcription factor (TF) genes that distinguish chondrocytes from osteoblasts reveals a shortlist of potential reprogramming factors exhibiting combined effects in inducing chondrogenesis of subchondral bone osteoblasts. A further combinatorial approach unexpectedly identified two 3-TF combinations containing Sox9 and Sox5 that exhibit differences in reprogramming propensity with the third TF c-Myc or Plagl1, which appeared to direct the converted chondrocytes toward either a superficial or a deeper zone phenotype. Thus, our approach demonstrates the possibility of converting osteoblasts into two major chondrocyte subpopulations with two combinations of three genes (Sox9, Sox5, and c-Myc or Plagl1). The findings may have important implications for developing novel in situ regeneration strategies for the reconstruction of full-thickness cartilage defects.

Effect of platelet-rich plasma scaffolding combined with osteochondral autograft transfer for full-thickness articular cartilage defects of the femoral condyle

We aimed to investigate the local application methods of platelet-rich plasma (PRP) and the effect and safety of PRP scaffolding combined with osteochondral autograft transfer (OAT) in the treatment of full-thickness articular cartilage defects of the femoral condyle. Patients with cartilage defects of the femoral condyle were treated with OAT combined with PRP scaffolding between July 2017 and December 2020. Preoperative magnetic resonance imaging (MRI) and computed tomography were utilized to assess the size, location, and severity of the osteochondral defects. X-ray and MRI images of the knee were obtained at the final follow-up to assess the osseointegration and integrity of the implanted articular cartilage. Osteoarthritic changes in the knee joint were evaluated using the Kellgren–Lawrence grading system. Clinical status was assessed using the visual analog scale (VAS), International Knee Documentation Committee (IKDC), and Lysholm scores before the treatment and at the final follow-up. Complications and patient satisfaction were recorded to assess the safety of this combination therapy. Twenty-one patients were recruited, with a mean follow-up duration of 18.23 ± 6.84 months. The mean lesion size was 2.3 ± 0.59 cm2. The mean platelet concentration in PRP at baseline was 6.27 ± 0.63 times greater than that in the peripheral blood. The VAS, IKDC, and Lysholm scores had improved significantly at the final follow-up (P < 0.001). No serious complications such as joint infection, deep venous thrombosis, or hematoma were observed. Eighteen patients (85.72%) were satisfied with their knee function and quality of life at the final follow-up. Three patients (14.28%) complained of mild anterior knee pain, which was relieved by oral administration of nonsteroidal anti-inflammatory drugs. MRI examinations of all patients showed bony consolidation and the defect surface was covered with cartilage-like tissue. X-ray evaluations indicated that osteoarthritis in two knees (9.5%) had progressed from grade 1 to grade 2 at the final follow-up. The preliminary results showed that OAT combined with PRP may be a safe and effective technique for the treatment of full-thickness articular cartilage defects in the knee.

Anchor Arthropathy Caused by Cartilage Penetration: An Approach to Revision Hip Arthroscopy With Removal of Problematic Anchors

Hip arthroscopy has been proven to effectively treat labral tears in the setting of femoroacetabular impingement. Anchors used for this treatment have constantly evolved and improved to ensure safety and minimal invasion. However, acetabular drilling and anchor placement are technically challenging due to the concavity of the acetabular articular surface, limited angles for anchor insertion, and finite bone availability in the anterior and posterior column. Inadequate technique can result in protruding anchors, which may lead to full-thickness articular cartilage damage, manifesting in pain, mechanical symptoms, and impaired function. This Technical Note demonstrates arthroscopic removal of protruding anchors and management of the iatrogenic grade IV cartilage damage. In this description, the technical pearls and pitfalls of acetabular anchor placement to treat labral pathology are presented along with the aforementioned technique.

Effect of uniform capacitively coupled electric fields on matrix metabolism of osteoarthritic cartilage

BackgroundOsteoarthritis (OA) is a common and debilitating condition characterized by degeneration of hyaline cartilage. Currently, there is no treatment for OA that directly targets degradation of cartilage matrix. Capacitively coupled electric fields (CCEFs) represent a noninvasive and cost-effective treatment modality that can potentially restore articular cartilage homeostasis. Previous studies showed that stimulation of articular cartilage with CCEFs resulted in upregulation of anabolic factors and downregulation of catabolic factors. These studies didn’t explain the derivation of the CCEFs or verify their uniformity and field strength, so it’s possible that cartilage wasn’t exposed to uniform field strength. The present study aims to employ CCEFs with verified uniform field strength in two in-vitro models of OA to investigate its potential to preserve cartilage matrix and validate the results of the aforementioned studies.MethodsRabbit hyaline chondrocytes and full-thickness bovine articular cartilage explants were cultured in the absence or presence of CCEF and in the absence or presence of Interleukin1-B (IL-1B). Quantitative polymerase chain reaction (QPCR) was performed on chondrocytes to measure gene expression of ADAM-TS4, MMP3, MMP9, IL-6, TIMP1, and TIMP2. QPCR was performed on explants to measure gene expression of MMP3, Aggrecan, Collagen-2, and TIMP1. Aggrecan concentration in explants was measured with histology. Statistical analysis was performed using one-way analysis of variance and Tukey–Kramer multiple comparison test.ResultsThe treatment of chondrocytes with IL-1B resulted in upregulated expression of ADAM-TS4, MMP3, MMP9, and IL-6, while simultaneous administration of IL-1B and CCEF led to a relative decrease in ADAM-TS4, MMP3, MMP9, and IL-6 expression and a relative increase in TIMP1 and TIMP2 expression. Application of IL-1B and CCEF to the explants resulted in decreased expression of MMP3 and increased expression of Aggrecan, Collagen-2, and TIMP1 when compared to application of IL-1B alone.ConclusionThe data indicate that application of a CCEF with verified uniformity may result in upregulation of cartilage anabolic factors even in the presence of IL-1B while attenuating IL-1B induced upregulation of catabolic factors in both monolayer culture and whole tissue. These results demonstrate the potential of CCEFs to suppress the progression of OA and regenerate articular cartilage matrix.

Short term clinical outcomes of a Prochondrix® thin laser-etched osteochondral allograft for the treatment of articular cartilage defects in the knee.

Objective: The purpose of this study is to evaluate the short-term clinical outcomes of Prochondrix® novel thin, laser-etched osteochondral allograft on isolated articular cartilage defects. Methods: Eighteen patients with isolated, symptomatic, full-thickness articular cartilage lesions were treated with marrow stimulation followed by placement of a T-LE allograft. Demographic and intra-operative data was recorded as well as pre- and post-operative International Knee Documentation Committee (IKDC), Short Form-36 (SF-36), Knee Injury and Osteoarthritis Outcome Score (KOOS), Visual Analogue Scale (VAS) and Tegner scores. Pre- and post-operative data was compared at 6, 12, 24 and 36months post operatively. Failures requiring reoperation were also recorded. Results: At a mean follow-up of 2.5years (6-43months), VAS decreased from 6.55 to 2.55 (p = .02) and subjective IKDC scores increased from 37.61 to 59.65 (p = .02). Statistically significant increases were also seen in KOOS Function-Sports and Recreational Activities (+26.04, p = .04) and KOOS QOL (+18.76, p = .007) as well as in SF-36 Physical Functioning (+25.20, p = .04), Energy/Fatigue (+16.50, p = .02), Social Functioning (+11.79, p = .04), and Bodily Pain (+25.18, p = .04). There were two failures requiring reoperation: one conversion to a patellofemoral arthroplasty (PFA), and one graft dislodgement which required removal. Conclusion: Treatment of articular cartilage lesions of the knee with ProChondrix® has demonstrated sustained positive results out to a mean follow-up of two and a half years in this prospective case series with a low failure rate that required reoperation (2 patients) in this series. These results are comparable to the short-term results of other cartilage restoration procedures currently in use today. A meta-analysis of osteochondral allografting demonstrated a mean 86.7% survival rate at 5 years with significant improvements in clinical outcome scores reaching MCID values.

Оценка синовита голеностопного сустава при диабетической нейроостеоартропатии в зависимости от воспалительной фазы хронического остеомиелита

Diabetic neuroosteoarthropathy complicated by osteomyelitis is one of the severe conditions of the ankle joint in patients with diabetes. The role of the synovium in the pathogenesis of this disease remains poorly understood. Purpose To identify structural changes in the synovium of the Charcot ankle depending on the inflammatory phase of chronic osteomyelitis. Material and methods The synovium and osteochondral fragments of the ankle were studied in 33 patients. Paraffin sections stained according to the three-color Masson method, hematoxylin and eosin, and semi-thin sections stained with methylene blue and basic fuchsin were studied using an AxioScope. A1 microscope with an AxioCam digital camera (Carl Zeiss MicroImaging GmbH, Germany) and Zenblue software (Carl Zeiss MicroImaging GmbH, Germany). The phase of the inflammatory process of chronic osteomyelitis was assessed according to the HOES of Tiemann et al (2014) and synovitis according to Krenn et al (2006). Results Full-thickness articular cartilage defects, synovial pannus, foci of osteonecrosis in the subchondral zone, bone microsequesters, osteoclastic resorption of the subchondral bone plate, replacement of bone marrow structures with granulation tissue, the severity which depended on the inflammatory stage of chronic osteomyelitis, were recorded in the process of studying osteochondral fragments. In 82 % of patients, the inflammatory phase of chronic osteomyelitis was characterized as active and subacute. In all the cases, hyperplasia, hypervascularization and hyperemia of the synovium with the presence of bone and cartilage fragments were observed, as well as inflammatory infiltrate, synovial pannus invading the articular cartilage. The vessels featured a pronounced narrowing of the lumens or their complete closure. The severity of synovitis correlated positively with the inflammatory phase of chronic osteomyelitis; Spearman's correlation coefficient of 0.76 indicated high relationship. Conclusions In diabetic osteoarthropathy of the ankle joint complicated by chronic osteomyelitis, the irreversible structural changes revealed in the synovium contribute to the formation of synovial pannus and the progression of destruction of the articular cartilage and subchondral bone. The severity of synovitis positively correlates with the inflammatory phase of chronic osteomyelitis.

Functionalized Hydrogels for Articular Cartilage Tissue Engineering

Articular cartilage (AC) is an avascular and flexible connective tissue located on the bone surface in the diarthrodial joints. AC defects are common in the knees of young and physically active individuals. Because of the lack of suitable tissue-engineered artificial matrices, current therapies for AC defects, especially full-thickness AC defects and osteochondral interfaces, fail to replace or regenerate damaged cartilage adequately. With rapid research and development advancements in AC tissue engineering (ACTE), functionalized hydrogels have emerged as promising cartilage matrix substitutes because of their favorable biomechanical properties, water content, swelling ability, cytocompatibility, biodegradability, and lubricating behaviors. They can be rationally designed and conveniently tuned to simulate the extracellular matrix of cartilage. This article briefly introduces the composition, structure, and function of AC and its defects, followed by a comprehensive review of the exquisite (bio)design and (bio)fabrication of functionalized hydrogels for AC repair. Finally, we summarize the challenges encountered in functionalized hydrogel-based strategies for ACTE both in vivo and in vitro and the future directions for clinical translation.