Comparative assessment of chondral defect repair using human bone marrow- and adipose tissue-derived mesenchymal stem cells, adult and foetal articular cartilage-derived chondrocytes, and chondroprogenitors: an ex-vivo model.

Purpose: Cartilage repair necessitates adjunct therapies such as cell-based approaches, which commonly use MSCs and chondrocytes but is limited by the formation of fibro-hyaline cartilage. Articular cartilage-derived chondroprogenitors(CPs) offer promise in overcoming this, as they exhibit higher chondrogenic and lower hypertrophic phenotypes. The study aimed to compare the efficacy of various cell types derived from adult and foetal cartilage suspended in platelet-rich plasma(PRP) in repairing chondral defects in an Ex-vivo Osteochondral Unit(OCU) model.

The effect of prebiotic fibre on the gut microbiome and surgical outcomes in patients with prosthetic joint infection (PENGUIN) - study protocol for a randomised, double-blind, placebo-controlled trial (ACTRN12623001273673).

Background: Prosthetic Joint Infection (PJI) is the most devastating complication of arthroplasty surgery and affects 1-5% of patients. Despite strict adherence to aseptic protocols and preventive measures, infection is the most common reason for revision arthroplasty, and the incidence is increasing. Treatment of PJI is challenging and often requires repeated major surgeries with sequentially poor results.

Isolation of Chondrocytes and Chondroprogenitors using Fibronectin Adhesion and Migratory Assay.

Chondroprogenitor cells (CPCs), recently identified as a distinct subpopulation, exhibit promise due to their mesenchymal properties, heightened chondrogenesis, and limited hypertrophic traits. The enrichment of progenitors is achieved through differential fibronectin adhesion and migration-based explant assays, with Fibronectin Adhesion Assay-derived Chondroprogenitors (FAA-CPs) and Migratory Chondroprogenitors (MCPs) demonstrating superior potential compared to chondrocytes. This article delves into the details of isolating resident cartilage-derived cells, namely chondrocytes and chondroprogenitors.

Evaluation of Chondral Defect Repair Using Human Fibronectin Adhesion Assay-Derived Chondroprogenitors Suspended in Lyophilized Fetal Collagen Scaffold: An Ex Vivo Osteochondral Unit Model Study.

Introduction: Chondral defect repair is challenging due to a scarcity of reparative cells and the need to fill a large surface area, compounded by the absence of self-healing mechanisms. Fibronectin adhesion assay-derived chondroprogenitors (FAA-CPs) have emerged as a promising alternative with enhanced chondrogenic ability and reduced hypertrophy. De-cellularized bio-scaffolds are reported to act as extracellular matrix, mimicking the structural and functional characteristics of native tissue, thereby facilitating cell attachment and differentiation.

Virtual biomechanical assessment of porous tantalum and custom triflange components in the treatment of patients with acetabular defects and pelvic discontinuity.

Aims: The aim of this study was to compare the biomechanical models of two frequently used techniques for reconstructing severe acetabular defects with pelvic discontinuity in revision total hip arthroplasty (THA) - the Trabecular Metal Acetabular Revision System (TMARS) and custom triflange acetabular components (CTACs) - using virtual modelling.

Methods: Pre- and postoperative CT scans from ten patients who underwent revision with the TMARS for a Paprosky IIIB acetabular defect with pelvic discontinuity were retrospectively collated. Computer models of a CTAC implant were designed from the preoperative CT scans of these patients.

Patient-Related Predictors of Treatment Failure After Two-Stage Total Hip Arthroplasty Revision for Periprosthetic Joint Infection: A Systematic Review and Meta-Analysis.

Background: Periprosthetic joint infection (PJI) treatment has high failure rates even after 2-stage revision. Risk factors for treatment failure (TF) after staged revision for PJI are not well defined, nor is it well established how they correlate with the risks of developing an index PJI. Identifying modifiable risk factors may allow preoperative optimization, while identifying nonmodifiable risk factors can influence surgical options or advise against further surgery.

Comparative assessment of chondral defect repair using migratory chondroprogenitors suspended in either gelled or freeze-dried platelet-rich plasma: An in vitro and ex vivo human osteochondral unit model study.

Background: Chondroprogenitors, with enhanced chondrogenic potential, have emerged to be a promising alternative for cell-based therapy in cartilage repair. Platelet-rich plasma (PRP), widely used for intra-articular treatment, has a short half-life. Freeze-dried PRP (FD-PRP), with an extended half-life and retained growth factors, is gaining attention.

Long Cephalomedullary Nails Can Be a Cheap and Effective Interval Revision Prosthesis in Infected Hip Replacements That Require Proximal Femoral Replacement: A Small Case Series.

Hip prosthetic joint infection management is complex and expensive, especially in severe bone loss. Reducing the price of interval prosthesis when performing staged revision could minimize costs without compromising outcomes. We present 2 similar techniques developed independently that use an antibiotic-coated cephalomedullary nail with a total hip arthroplasty bearing (head and cemented acetabular component) attached to it as an interval proximal femoral replacement prosthesis.

Human fetal cartilage-derived chondrocytes and chondroprogenitors display a greater commitment to chondrogenesis than adult cartilage resident cells.

Obtaining regeneration-competent cells and generating high-quality neocartilage are still challenges in articular cartilage tissue engineering. Although chondroprogenitor cells are a resident subpopulation of native cartilage and possess a high capacity for proliferation and cartilage formation, their potential for regenerative medicine has not been adequately explored. Fetal cartilage, another potential source with greater cellularity and a higher cell-matrix ratio than adult tissue, has been evaluated for sourcing cells to treat articular disorders.

RSA Measurements of Implant Instability in a Paprosky III Pelvic Defect with Discontinuity: A Case Report.

Case: We report a case of acetabular reconstruction for a large defect with pelvic discontinuity that underwent 4 revisions for dislocations over a 3-year period. This allowed assessment of implant stability both on imaging, using measurements on plain radiographs and radiostereometric analysis (RSA) against both ilium and ischium, and direct assessment during each surgery. Only implant stability measured with RSA correlated with intraoperative revision findings.

Systematic review of articular cartilage derived chondroprogenitors for cartilage repair in animal models.

Purpose Of Research: The potential for cartilage repair using articular cartilage derived chondroprogenitors has recently gained popularity due to promising results from in-vitro and in-vivo studies. Translation of results from in-vitro to a clinical setting requires a sufficient number of animal studies displaying significant positive outcomes. Thus, this systematic review comprehensively discusses the available literature (January 2000-March 2022) on animal models employing chondroprogenitors for cartilage regeneration, highlighting the results and limitations associated with their use.

Migratory chondroprogenitors retain superior intrinsic chondrogenic potential for regenerative cartilage repair as compared to human fibronectin derived chondroprogenitors.

Cell-based therapy for articular hyaline cartilage regeneration predominantly involves the use of mesenchymal stem cells and chondrocytes. However, the regenerated repair tissue is suboptimal due to the formation of mixed hyaline and fibrocartilage, resulting in inferior long-term functional outcomes. Current preclinical research points towards the potential use of cartilage-derived chondroprogenitors as a viable option for cartilage healing.

The Role of the Ilizarov Ring External Fixator in the Management of Tibial Fractures with Impending/Incomplete Compartment Syndrome.

 The management of tibia fractures complicated by compartment syndrome affects the treatment and functional outcome of patients due to the complications associated with fasciotomy. The purpose of the present study is to differentiate impending/incomplete compartment syndrome (ICS) from established acute compartment syndrome (ACS) in tibial fractures, and to assess the outcome of the fixation of the Ilizarov apparatus in patients with these fractures presenting with ICS, who were not submitted to fasciotomy.  After the establishment of the inclusion and exclusion criteria, 19 patients were included in the study from January 2007 to December 2017.

Prospective Isolation and Characterization of Chondroprogenitors from Human Chondrocytes Based on CD166/CD34/CD146 Surface Markers.

Purpose: Chondrocytes, isolated from articular cartilage, are routinely utilized in cell-based therapeutics for the treatment of cartilage pathologies. However, restoration of the biological tissue faces hindrance due to the formation of primarily fibrocartilaginous repair tissue. Chondroprogenitors have been reported to display superiority in terms of their chondrogenic potential and lesser proclivity for hypertrophy.

Use of an Angled Blade Plate for 31A3 Intertrochanteric Fractures.

Background: A subgroup of pertrochanteric fractures-namely, the AO/OTA 31A3 fracture-continues to be a difficult problem to treat, even with cephalomedullary nails. We present the results for 26 patients with a 31A3 fracture treated with the angled blade plate.

Methods: The records of 26 consecutive patients with a 31A3 fracture that was treated operatively with the angled blade plate device between 2007 and 2012 at our center were reviewed, and the patients were contacted for follow-up.

Association of Gut Microbiome and Vitamin D Deficiency in Knee Osteoarthritis Patients: A Pilot Study.

Background: Few preclinical studies have shown that Knee osteoarthritis (KOA) is linked to gut microbiome dysbiosis and chronic inflammation. This pilot study was designed to look at the gut microbiome composition in KOA patients and normal individuals with or without vitamin D deficiency (VDD, serum vitamin D <30 ng/mL).

Methods: This pilot study was conducted prospectively in 24 participants.

Articular chondroprogenitors in platelet rich plasma for treatment of osteoarthritis and osteochondral defects in a rabbit knee model.

Background: Articular chondroprogenitors are a promising contender for cartilage repair due to their inherent nature which stands primed for chondrogenesis and minimal hypertrophic preponderance. Platelet rich plasma (PRP) has been extensively used for treating cartilage defects and osteoarthritis (OA), due to its chondro-inductive properties and abundant pool of growth factors. The aim of this study was to assess the efficacy of chondroprogenitors injected with PRP versus PRP alone in the healing of experimentally created early OA and osteochondral defects (OCD) in a rabbit model.

In vitro chondrogenic differentiation of human articular cartilage derived chondroprogenitors using pulsed electromagnetic field.

Background: The ability to grow new cartilage remains the standard goal of any treatment strategy directed at cartilage repair. Chondroprogenitors have garnered interest due to their applicability in cell therapy. Pulsed electromagnetic field (PEMF) favors chondrogenesis by possible upregulation of genes belonging to TGFβ superfamily.

Pondering the Potential of Hyaline Cartilage-Derived Chondroprogenitors for Tissue Regeneration: A Systematic Review.

Objective: Chondroprogenitors have recently gained prominence due to promising results seen in and animal studies as a potential contender in cell-based therapy for cartilage repair. Lack of consensus regarding nomenclature, isolation techniques, and expansion protocols create substantial limitations for translational research, especially given the absence of distinct markers of identification. The objective of this systematic review was to identify and collate information pertaining to hyaline cartilage-derived chondroprogenitors, with regard to their isolation, culture, and outcome measures.

Characterization of human articular chondrocytes and chondroprogenitors derived from non-diseased and osteoarthritic knee joints to assess superiority for cell-based therapy.

Purpose: Cell based therapy is constantly underway since regeneration of genuine hyaline cartilage is under par. Much attention has been afforded to chondroprogenitors recently, as an alternative cell substitute for cartilage repair. Although single source derivation of chondrocytes and chondroprogenitors is advantageous, lack of a characteristic differentiating marker obscures clear identification, which is essential to create a biological profile and is also required to assess cell type superiority for cartilage repair.

Correlation between synovial fluid calcium containing crystal estimation and varying grades of osteoarthritis created using a rabbit model: Potential diagnostic tool.

Objectives: Accurate diagnosis of osteoarthritis (OA) is the first important step in ensuring appropriate management of the disease. A multitude of tests involving assessment of biomarkers help in assessment of severity and grading of osteoarthritic damage. However, most tests are time consuming and are limited by the paucity in synovial fluid volume.

Bilayer nanostructure coated AZ31 magnesium alloy implants: in vivo reconstruction of critical-sized rabbit femoral segmental bone defect.

Healing or reconstruction of critical-sized bone defects is still challenging in orthopaedic practice. In this study, we developed a new approach to control the degradation and improve the bone regeneration of the AZ31 magnesium substrate, fabricated as mesh cage implants. Subsequently, bilayer nanocomposite coating was carried out using polycaprolactone (PCL) and nano-hydroxyapatite (nHA) by dip-coating and electrospinning.

Comparison of the efficiency of laminin versus fibronectin as a differential adhesion assay for isolation of human articular cartilage derived chondroprogenitors.

: Cartilage repair following trauma or degeneration is poor, making cell-based therapy an important avenue of treatment. Chondrocytes and mesenchymal stem cells have been extensively studied as potential candidates, although tendency toward hypertrophy and formation of mixed hyaline-fibrocartilage necessitates further optimization. Chondroprogenitors, isolated using fibronectin adhesion assay are reported to show reduced hypertrophy and enhanced chondrogenesis.

Evaluation of CD49e as a distinguishing marker for human articular cartilage derived chondroprogenitors.

Background: Cell-based therapy in cartilage repair can benefit from the use of chondroprogenitors; a cell type classified as mesenchymal stem cells, demonstrating reduced hypertrophy. Fibronectin, routinely used to isolate chondroprogenitors, classically binds to α5β1 integrins (CD49e + CD29), of which CD49e is said to be highly expressed in progenitors. The aim of our study was to assess the specificity of CD49e as a distinguishing marker for chondroprogenitors; because studies report low expression in fresh chondrocytes (FCs), but recent conflicting data has exhibited incremental expression of CD49e in cultured chondrocytes.

Time to debridement in open high-grade lower limb fractures and its effect on union and infections: A prospective study in a tropical setting.

Purpose: To prospectively evaluate whether time to debridement has any correlation with union, infection, and quality of life in high-grade lower limb fractures in a tropical setting.

Methods: A prospective cohort study was conducted at a tertiary care center in South India. Two hundred fifty-four adult skeletally mature patients with 301 grade 3 fractures involving the femur, tibia, or fibula were recruited.