Surgical treatment options for articular cartilage defects of the glenohumeral joint: A systematic review

Background

Many joint-preserving surgical interventions for cartilage defects of the knee have been adapted for use in the shoulder; however, there still exists no clear consensus for treatment. Thus, the purpose of this systematic review was to evaluate the outcomes of different interventions in patients with focal chondral lesions of the glenohumeral joint.

Methods

A literature search was conducted using PubMed, Embase, and Medline. Patients who underwent a joint-preserving surgical procedure to treat a focal chondral defect of the glenoid, humeral head or both were included. Patients treated for diffuse cartilage defects or with shoulder arthroplasty were excluded.

Results

Ten studies were included, with follow-up data available for 194 shoulders. Eight joint-preserving procedures were evaluated, with microfracture being the most common. One study evaluating microfracture reported significant improvements in patient-reported outcomes at short-term and long-term follow-up compared to preoperative scores. Across all studies, 32 patients underwent subsequent shoulder surgery, with 22 being arthroplasties.

Conclusions

We found improvements in patient-reported and functional outcomes across all studies. Although joint-preserving procedures have shown reasonable outcomes for focal chondral defects of the glenohumeral joint, long-term outcomes remain unknown, and the progression of osteoarthritis remains a concern. Higher quality evidence is required to make definitive recommendations.

Level of Evidence

IV.

Immunohistochemical Analysis of Knee Chondral Defect Repair after Autologous Particulated Cartilage and Platelet-Rich Plasma Treatment in Sheep

This study performs an analysis that will enable the evaluation of the quality, durability, and structure of repaired cartilaginous extracellular matrix tissue using an autologous-based particulated autograft cartilage and platelet-rich plasma treatment (PACI + PRP). A single-blind controlled experiment was conducted on 28 sheep to evaluate the efficacy of the PACI + PRP treatment for cartilage defects. Full-thickness 8 mm diameter defects were created in the weight-bearing area of both knees. The right knees received PACI + PRP. The left knees were treated with Ringer's lactate solution (RLS) or hyaluronic acid (HA) injections. Sheep were euthanized at 9- or 18-months post-surgery. An extensive immunohistochemical analysis was performed to assess collagen types (I, II, III, V, VI, IX, X, XI) and aggrecan positivity. A semiquantitative scoring system provided a detailed evaluation of immunostaining. Collagens and aggrecan scores in the PACI + PRP groups were similar to healthy cartilage. Significant differences were found in collagens associated with matrix maturity (II and V), degradation (IX), structure and mechanics (VI), and hypertrophy (X) between healthy cartilage and RLS- or HA-repaired cartilage. The PACI + PRP treatment advanced the repair cartilage process in chondral defects with mature hyaline cartilage and enhanced the structural and mechanical qualities with better consistent cartilage, less susceptible to degradation and without hypertrophic formation over time.

Clinical and Magnetic Resonance Imaging Outcomes After Human Cord Blood-Derived Mesenchymal Stem Cell Implantation for Chondral Defects of the Knee

Background

There is a paucity of literature reporting clinical and magnetic resonance imaging (MRI) outcomes after allogeneic umbilical cord blood-derived mesenchymal stem cell (UCB-MSC) implantation for chondral defects of the knee.

Purpose

To report clinical and MRI outcomes after UCB-MSC implantation for chondral lesions of the knee.

Study Design

Case series; Level of evidence, 4.

Methods

Inclusion criteria were patients aged between 40 and 70 years with focal chondral lesions of grade 3 or 4 on the medial femoral condyle, defect sizes >4 cm², and intact ligaments. Exclusion criteria were patients who required realignment osteotomy or who had a meniscal deficiency, ligamentous instability, or a concomitant full-thickness chondral defect in the lateral or patellofemoral compartment. A mixture of human UCB-MSCs and sodium hyaluronate was implanted into the chondral defect through mini-arthrotomy. MRI at 1-year follow-up was performed to evaluate repaired cartilage hypertrophy. Repaired cartilage thickness was measured, and hypertrophy was classified as grade 1 (<125%), grade 2 (<150%), or grade 3 (<200%). Patient-reported outcomes (PROs; International Knee Documentation Committee, visual analog scale for pain, and Western Ontario and McMaster Universities Osteoarthritis Index) were evaluated preoperatively and at 1, 2, and 3 years postoperatively. Repaired cartilage hypertrophy was evaluated for a correlation with PRO scores.

Results

Enrolled were 85 patients with a mean age of 56.8 ± 6.1 years and a mean chondral defect size of 6.7 ± 2.0 cm². At follow-up, a significant improvement in all PRO scores was seen compared with preoperatively (P < .001 for all). MRI at 1-year follow-up demonstrated that 28 patients had grade 1 repaired cartilage hypertrophy, 41 patients had grade 2, and 16 patients had grade 3. MRI performed in 11 patients at 2 years after surgery indicated no difference in repaired cartilage hypertrophy between the 1- and 2-year time points. The grade of repaired cartilage hypertrophy did not correlate with PRO scores.

Conclusion

Clinical outcomes improved significantly at short-term follow-up after UCB-MSC implantation. Although all patients showed repaired cartilage hypertrophy, it did not correlate with clinical outcomes.

Intra-osseous plasma rich in growth factors enhances cartilage and subchondral bone regeneration in rabbits with acute full thickness chondral defects: Histological assessment

Background

Intra-articular (IA) combined with intra-osseous (IO) infiltration of plasma rich in growth factors (PRGF) have been proposed as an alternative approach to treat patients with severe osteoarthritis (OA) and subchondral bone damage. The aim of the study is to evaluate the efficacy of IO injections of PRGF to treat acute full depth chondral lesion in a rabbit model by using two histological validated scales (OARSI and ICRS II).

Methodology

A total of 40 rabbits were included in the study. A full depth chondral defect was created in the medial femoral condyle and then animals were divided into 2 groups depending on the IO treatment injected on surgery day: control group (IA injection of PRGF and IO injection of saline) and treatment group (IA combined with IO injection of PRGF). Animals were euthanized 56 and 84 days after surgery and the condyles were processed for posterior histological evaluation.

Results

Better scores were obtained in treatment group in both scoring systems at 56- and 84-days follow-up than in control group. Additionally, longer-term histological benefits have been obtained in the treatment group.

Conclusions

The results suggests that IO infiltration of PRGF enhances cartilage and subchondral bone healing more than the IA-only PRGF infiltration and provides longer-lasting beneficial effects.

Intra-osseous infiltration of adipose mesenchymal stromal cells and plasma rich in growth factors to treat acute full depth cartilage defects in a rabbit model: Serum osteoarthritis biomarkers and macroscopical assessment

Introduction

Intra-articular infiltration of plasma rich in growth factors (PRGF) and adipose mesenchymal stromal cells (AMSCs) are known to inhibit osteoarthritis progression. However, in severely affected patients, the treatment cannot reach the deeper layers of the articular cartilage; thus, its potential is limited. To overcome this limitation, intra-osseous infiltrations have been suggested. The purpose of this study is to assess the impact of intra-osseous infiltration therapies on serum biomarkers of osteoarthritis and to assess cartilage regeneration macroscopically.

Materials and methods

A total of 80 rabbits were divided into four groups based on the intra-osseous treatment administered on the day of surgery: control, PRGF, AMSCs and a combination of PRGF + AMSCs. In addition, all groups received a single intra-articular administration of PRGF on the same day. Serum biomarker levels were measured before infiltration and 28-, 56-, and 84-days post infiltration, and macroscopical assessment was conducted at 56- and 84-days follow-up post infiltration.

Results

In the PRGF + AMSCs group, significantly lower concentrations of hyaluronic acid and type II collagen cleavage neoepitope were recorded at all time points during the study, followed by PRGF, AMSCs and control groups. Regarding macroscopical assessment, lower scores were obtained in PRGF + AMSCs group at all study times.

Discussion

The results suggest that the combination of intra-articular PRGF with intra-osseous PRGF or AMSCs achieves better results in rabbits with acute chondral defects and that intra-osseous infiltration is a safe procedure.

Small Chondral Defects Affect Tibiofemoral Contact Area and Stress: Should a Lower Threshold Be Used for Intervention?

BACKGROUND

Chondral defects in the knee have biomechanical differences because of defect size and location. Prior literature only compares the maximum stress experienced with large defects.

HYPOTHESIS

It was hypothesized that pressure surrounding the chondral defect would increase with size and vary in location, such that a size cutoff exists that suggests surgical intervention.

STUDY DESIGN

Controlled laboratory study.

METHODS

Isolated chondral defects from 0.09 to 1.0 cm2 were created on the medial and lateral femoral condyles of 6 human cadaveric knees. The knees were fixed to a uniaxial load frame and loaded from 0 to 600 N at full extension. Another defect was created at the point of tibiofemoral contact at 30° of flexion. Tibiofemoral contact pressures were measured. Peak contact pressure was the highest value in the area delimited within a 3-mm rim around the defect. The location of the peak contact pressure was determined.

RESULTS

At full extension, the mean maximum pressures on the medial femoral condyle ranged from 4.30 to 6.91 MPa at 0.09 and 1.0 cm2, respectively (P < .01). The location of the peak pressure was found posteromedial in defects between 0.09 and 0.25 cm2, shifting anterolaterally at sizes 0.49 and 1.0 cm2 (P < .01). The maximum pressures on the lateral femoral condyle ranged from 3.63 to 5.81 MPa at 0.09 and 1.0 cm2, respectively (P = .02). The location of the peak contact pressure point was anterolateral in defects between 0.09 and 0.25 cm2, shifting posterolaterally at 0.49 and 1.0 cm2 (P < .01). No differences in contact pressure between full extension and 30° of flexion were found for either the lateral or medial condyles.

CONCLUSION

Full-thickness chondral defects bilaterally had a significant increase in contact pressure between defect sizes of 0.49 and 1.0 cm2. The location of the maximum contact pressures surrounding the lesion also varied with larger defects. Contact area redistribution and cartilage stress change may affect adjacent cartilage integrity.

CLINICAL RELEVANCE

Size cutoffs may exist earlier in the natural history of chondral defects than previously realized, suggesting a lower threshold for intervention.

Autologous Matrix-Induced Chondrogenesis (AMIC) for Osteochondral Defects of the Talus: A Systematic Review

Autologous matrix-induced chondrogenesis (AMIC) has been advocated for the management of talar osteochondral lesions (OCLs). This systematic review, which was conducted according to the PRISMA 2020 guidelines, investigated the clinical and imaging efficacy and safety of the AMIC technique in the management of OCLs of the talus. Only studies investigating AMIC for talar chondral defects that were published in peer-reviewed journals were considered. In September 2022, the following databases were accessed: PubMed, Web of Science, Google Scholar, and Embase. Data on the visual analogue scale (VAS), American Orthopaedic Foot and Ankle Score (AOFAS), Tegner activity scale, and Foot Function Index (FFI) were retrieved. To evaluate the morphological MRI findings, data obtained from the magnetic resonance observation of cartilage repair tissue (MOCART) scores were evaluated. Data on hypertrophy, failures, and revision surgeries were also collected. Data from 778 patients (39% women, 61% men) were collected. The mean length of the follow-up was 37.4 ± 16.1 months. The mean age of the patients was 36.4 ± 5.1 years, and the mean BMI was 26.1 ± 1.6 kg/m2. The mean defect size was 2.1 ± 1.9 cm2. Following the AMIC technique, patients demonstrated an improved VAS (p < 0.001), AOFAS (p < 0.001), and FFI (p = 0.02) score. The MOCART score also improved from the baseline (p = 0.03). No difference was observed in the Tegner score (p = 0.08). No graft delamination and hypertrophy were reported in 353 patients. 7.8% (44 of 564) of patients required revision surgeries, and 6.2% (32 of 515) of patients were considered failures. The AMIC technique could be effective in improving symptoms and the function of chondral defects of the talus.

Fixation of the Membrane during Matrix-Induced Autologous Chondrocyte Implantation in the Knee: A Systematic Review

Introduction: It is unclear whether the type of membrane used for matrix-assisted autologous chondrocyte implantation (mACI) influences results. A systematic review was conducted to investigate the midterm results of the three most common types of membrane fixation for mACI. Methods: This systematic review was conducted according to the 2020 PRISMA checklist. PubMed, Google Scholar, Embase, and Scopus online databases were accessed in August 2022. All the prospective clinical trials reporting outcomes of mACI in the knee were considered. Studies that describe the modality of membrane fixation (glued, glued, and sutured, no fixation) used for mACI were eligible. Studies that conducted a minimum of 12 months of follow-up were considered. The outcomes of interest were the Tegner Activity Scale and International Knee Documentation Committee (IKDC) score. The rate of failure and revisions were also collected. Results: Data from 26 studies (1539 procedures; 554 of 1539 (36%) were women) were retrieved. The mean follow-up was 42.6 (12 to 84) months. No difference between the groups was found in terms of mean duration of symptoms, age, BMI, gender, and defect size (P > 0.1). No difference was found in terms of the Tegner score (P = 0.3). When no fixation was used, a statistically significant higher IKDC compared to the other groups (P = 0.02) was evidenced. No difference was found in the rate of failure (P = 0.1). The no-fixation group evidenced a statistically significant lower rate of revisions (P = 0.02). Conclusions: No membrane fixation for mACI in the knee scored better than the fastening techniques at the midterm follow-up.

Surgical Management of Focal Chondral Defects of the Talus: A Bayesian Network Meta-analysis

BACKGROUND

No consensus has been reached regarding the optimal surgical treatment for focal chondral defects of the talus.

PURPOSE

A Bayesian network meta-analysis was conducted to compare the clinical scores and complications of mosaicplasty, osteochondral auto- and allograft transplant, microfracture, matrix-assisted autologous chondrocyte transplant, and autologous matrix-induced chondrogenesis (AMIC) for chondral defects of the talus at midterm follow-up.

STUDY DESIGN

Bayesian network meta-analysis; Level of evidence, 4.

METHODS

This Bayesian network meta-analysis followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) extension statement for reporting of systematic reviews incorporating network meta-analyses of health care interventions. PubMed, Embase, Google Scholar, and Scopus databases were accessed in February 2021. All clinical trials comparing 2 or more surgical interventions for the management of chondral defects of the talus were accessed. The outcomes of interest were visual analog scale (VAS) score, American Orthopaedic Foot and Ankle Society (AOFAS) score, rate of failure, and rate of revision surgery. The network meta-analysis were performed through the routine for Bayesian hierarchical random-effects model analysis. The log odds ratio (LOR) effect measure was used for dichotomous variables, and the standardized mean difference (SMD) was used for continuous variables.

RESULTS

Data from 13 articles (521 procedures) were retrieved. The median length of the follow-up was 47.8 months (range, 31.7-66.8 months). Analysis of variance revealed no difference between the treatment groups at baseline in terms of age, sex, body mass index, AOFAS score, VAS score, and mean number of defects. AMIC demonstrated the greatest AOFAS score (SMD, 11.27) and lowest VAS score (SMD, -2.26) as well as the lowest rates of failure (LOR, 0.94) and revision (LOR, 0.94). The test for overall inconsistency was not significant.

CONCLUSION

At approximately 4 years of follow-up, the AMIC procedure for management of focal chondral defects of the talus produced the best outcome.

Matrix-induced autologous chondrocyte implantation (mACI) versus autologous matrix-induced chondrogenesis (AMIC) for chondral defects of the knee: a systematic review

INTRODUCTION

Chondral defects of the knee are common and their treatment is challenging.

SOURCE OF DATA

PubMed, Google scholar, Embase and Scopus databases.

AREAS OF AGREEMENT

Both autologous matrix-induced chondrogenesis (AMIC) and membrane-induced autologous chondrocyte implantation (mACI) have been used to manage chondral defects of the knee.

AREAS OF CONTROVERSY

It is debated whether AMIC and mACI provide equivalent outcomes for the management of chondral defects in the knee at midterm follow-up. Despite the large number of clinical studies, the optimal treatment is still controversial.

GROWING POINTS

To investigate whether AMIC provide superior outcomes than mACI at midterm follow-up.

AREAS TIMELY FOR DEVELOPING RESEARCH

AMIC may provide better outcomes than mACI for chondral defects of the knee. Further studies are required to verify these results in a clinical setting.

Hypothermically Stored Amniotic Membrane for the Treatment of Cartilage Lesions: A Single-Arm Prospective Study with 2-Year Follow-Up

OBJECTIVE

The purpose of this study was to determine the safety and efficacy of hypothermically stored amniotic membrane (HSAM) for the treatment of cartilage lesions of the knee using imaging, patient-reported outcomes (PROs), second-look arthroscopy, and histology. Patients were treated with HSAM and followed for 2 years.

DESIGN

Subjects with focal chondral lesions of the femur (International Cartilage Repair Society grade 3-4) were enrolled in this single-arm prospective study. Standard of care imaging was completed. PROs, including the Knee Injury and Osteoarthritis Outcome Score (KOOS), Marx Activity Scale, and Visual Analog Scale (VAS), were collected at baseline and at 3, 6, 12, 18, and 24 months. Three subjects underwent an optional arthroscopy and biopsy of the repair at 24 months.

RESULTS

Ten subjects were enrolled and completed the study. At 24 months, KOOS Sports & Recreation improved 173.3% and Quality of Life improved 195.3% from baseline. Marx Activity Scale increased 266.8% from 12 to 24 months. VAS scores improved 84.8% and 81.0% from baseline to 24 months for average and maximum pain. Modified Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) scoring showed that 7 of 10 subjects had complete defect repair and filling by 24 months. Biopsy staining for collagen II revealed integration and remodeling of HSAM into a mix of hyaline-like cartilage and fibrocartilage matrix.

CONCLUSION

This study provides evidence supporting the safety and efficacy of HSAM for treating symptomatic cartilage lesions. Subjects showed a high degree of defect fill and integration with the native cartilage and reported improvements in pain and function post-treatment. Results provide important original data for future clinical trials.

Membrane scaffolds for matrix-induced autologous chondrocyte implantation in the knee: a systematic review

INTRODUCTION

Chondral defects of the knee are common and their management is challenging.

SOURCE OF DATA

Current scientific literature published in PubMed, Google scholar, Embase and Scopus.

AREAS OF AGREEMENT

Membrane-induced autologous chondrocyte implantation (mACI) has been used to manage chondral defects of the knee.

AREAS OF CONTROVERSY

Hyaluronic acid membrane provides better outcomes than a collagenic membrane for mACI in the knee at midterm follow-up is controversial.

GROWING POINTS

To investigate whether hyaluronic acid membrane may provide comparable clinical outcomes than collagenic membranes for mACI in focal defects of the knee.

AREAS TIMELY FOR DEVELOPING RESEARCH

Hyaluronic acid membrane yields a lower rate of failures and revision surgeries for mACI in the management of focal articular cartilage defects of the knee compared with collagenic scaffolds at midterm follow-up. No difference was found in patient reported outcome measures (PROMs). Further comparative studies are required to validate these results in a clinical setting.

Combination of a Collagen Scaffold and an Adhesive Hyaluronan-Based Hydrogel for Cartilage Regeneration: A Proof of Concept in an Ovine Model

OBJECTIVE

Hyaluronic acid-transglutaminase (HA-TG) is an enzymatically crosslinkable adhesive hydrogel with chondrogenic properties demonstrated in vitro and in an ectopic mouse model. In this study, we investigated the feasibility of using HA-TG in a collagen scaffold to treat chondral lesions in an ovine model, to evaluate cartilage regeneration in a mechanically and biologically challenging joint environment, and the influence of the surgical procedure on the repair process.

DESIGN

Chondral defects of 6-mm diameter were created in the stifle joint of skeletally mature sheep. In a 3-month study, 6 defects were treated with HA-TG in a collagen scaffold to test the stability and biocompatibility of the defect filling. In a 6-month study, 6 sheep had 12 defects treated with HA-TG and collagen and 2 sheep had 4 untreated defects. Histologically observed quality of repair tissue and adjacent cartilage was semiquantitatively assessed.

RESULTS

HA-TG adhered to the native tissue and did not cause any detectable negative reaction in the surrounding tissue. HA-TG in a collagen scaffold supported infiltration and chondrogenic differentiation of mesenchymal cells, which migrated from the subchondral bone through the calcified cartilage layer. Additionally, HA-TG and collagen treatment led to better adjacent cartilage preservation compared with empty defects (P < 0.05).

CONCLUSIONS

This study demonstrates that the adhesive HA-TG hydrogel in a collagen scaffold shows good biocompatibility, supports in situ cartilage regeneration and preserves the surrounding cartilage. This proof-of-concept study shows the potential of this approach, which should be further considered in the treatment of cartilage lesions using a single-step procedure.

Using apheresis-derived cells to augment microdrilling in the treatment of chondral defects in an ovine model

The treatment of chondral defects using microdrilling often results in a mechanically weak fibrocartilagenous repair, rather than a more robust hyaline cartilage repair. Many different microfracture/microdrilling augmentation techniques have been described, including the use of cellular products to enhance healing. Autologous peripheral blood progenitor cells can be obtained via apheresis after administration of granulocyte colony-stimulating factor (G-CSF) and have been used successfully to augment microdrilling in clinical patients. The objective of this study was to use apheresis-derived mononuclear blood cells to augment microdrilling treatment of a cartilage defect in an ovine model to determine the effect on healing. Forty adult female sheep were used in this study and were divided into a control group (microdrilling alone) and a treatment group (microdrilling, hyaluronic acid, and apheretic product). Outcome measurements included weight-bearing on the operated limb, macroscopic scoring of the joint, histology, and immunohistochemistry. In addition, magnetic resonance imaging was used to attempt to identify SPION-labeled cells from the apheretic product in the operated limbs. The results showed a significant increase in healing as measured by the modified O'Driscoll sore in the treated group. No evidence of homing of SPION-labeled cells to the defect was found and no correlation was found between the response to G-CSF administration or concentration of CD34⁺  and outcome. A correlation was found between healing and the concentration of white blood cells and peripheral blood mononuclear cell numbers in the apheretic product.

Matrix-induced autologous chondrocyte implantation versus autologous matrix-induced chondrogenesis for chondral defects of the talus: a systematic review

INTRODUCTION

Chondral defects of the talus are common and their treatment is challenging.

SOURCE OF DATA

Recent published literatures.

AREAS OF AGREEMENT

Membrane-induced Autologous Chondrocyte Implantation (mACI) and Autologous Matrix-Induced Chondrogenesis (AMIC) have been proposed as management for chondral defects of the talus.

AREAS OF CONTROVERSY

It is debated whether AMIC provides greater outcomes compared to mACI for chondral regeneration. Several clinical studies showed controversial results, and the best treatment has not yet been clarified.

GROWING POINTS

To investigate whether AMIC provide superior outcomes than mACI at midterm follow-up.

AREAS TIMELY FOR DEVELOPING RESEARCH

AMIC exhibits similar clinical results to mACI. However, AMIC involves one single surgical procedure, no articular cartilage harvest and hence no morbidity from it, no need for chondrocyte expansion in a separate laboratory setting. For these reasons, AMIC may be preferred to mACI.

Autologous Matrix Induced Chondrogenesis (AMIC) Compared to Microfractures for Chondral Defects of the Talar Shoulder: A Five-Year Follow-Up Prospective Cohort Study

Introduction: Many procedures are available to manage cartilage defects of the talus, including microfracturing (MFx) and Autologous Matrix Induced Chondrogenesis (AMIC). Whether AMIC or MFx are equivalent for borderline sized defects of the talar shoulder is unclear. Thus, the present study compared the efficacy of primary isolated AMIC versus MFx for borderline sized focal unipolar chondral defects of the talar shoulder at midterm follow-up. Methods: Patients undergoing primary isolated AMIC or MFx for focal unipolar borderline sized chondral defects of the talar shoulder were recruited prospectively. For those patients who underwent AMIC, a type I/III collagen resorbable membrane was used. The outcomes of interest were: Visual Analogic Scale (VAS), Tegner Activity Scale, American Orthopedic Foot and Ankle Score (AOFAS). The Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) was assessed by a blinded radiologist, who had not been involved in the clinical management of the patients. Data concerning complication rate and additional procedures were also collected. Results: The mean follow-up was 43.5 months. The mean age of the 70 patients at operation was 32.0 years, with a mean defect size of 2.7 cm². The mean length of hospitalization was shorter in the MFx cohort (p = 0.01). No difference was found between the two cohorts in terms of length of prior surgery symptoms and follow-up, mean age and BMI, sex and side, and defect size. At a mean follow-up of 43.5 months, the AOFAS (p = 0.03), VAS (p = 0.003), and Tegner (p = 0.01) scores were greater in the AMIC group. No difference was found in the MOCART score (p = 0.08). The AMIC group evidenced lower rates of reoperation (p = 0.008) and failure (p = 0.003). Conclusion: At midterm follow-up, AMIC provides better results compared to MFx.

Surgical Fixation of Chondral-Only Fragments of the Knee: A Case Series With a Mean 4-Year Follow-up

Background:

Chondral-only fragments of the knee have traditionally been treated with excision, with or without cartilage restoration procedures. This is because of the historical assumption that cartilage has limited ability to heal to cancellous or subchondral bone. There is now a growing body of evidence supporting surgical fixation of these fragments.

Hypothesis:

We hypothesized that surgical fixation of chondral fragments would result in acceptable rates of healing with improvement in clinical outcome scores.

Study Design:

Case series; Level of evidence, 4.

Methods:

Data were collected on 15 surgically fixed chondral-only fragments in 14 patients. We retrospectively collected participant demographic information, lesion characteristics, primary mechanism (osteochondritis dissecans vs traumatic shear injury), fixation methods, reoperation information, second-look arthroscopic information, and clinical outcome scores. The mean clinical follow-up was 3.96 years, with a minimum of 1-year follow-up. All patients underwent follow-up magnetic resonance imaging at a mean of 2 years after the index procedure.

Results:

The mean age of our cohort was 17.7 years. We found an 80% survival rate for fixation of the fragments at a mean 4-year follow-up. There were statistically significant improvements in postoperative Knee injury and Osteoarthritis Outcome Score and Tegner scores compared with preoperative scores. Follow-up magnetic resonance imaging scans showed complete healing in 10 knees, partial healing in 2 knees, and loss of fixation in 3 knees. Second-look arthroscopic surgery of 3 knees for reasons other than fragment symptoms showed healing of the fragment, while arthroscopic surgery of 3 symptomatic knees showed loss of fixation.

Conclusion:

Surgical fixation of chondral-only lesions showed an 80% success rate with improvements in the KOOS and Tegner scores.

Human Stem Cell Based Tissue Engineering for In Vivo Cartilage Repair: A Systematic Review

Pure chondral defects represent the most clinically significant articular cartilage injuries. To inform the development of clinically suitable tissue-engineering strategies for chondral repair using cells from a human patient, the combination of human stem cells (HSCs), biomaterial scaffolds, and growth factors has been widely harnessed in preclinical animal models. Due to the large heterogeneity in study designs and outcome reporting in such studies, we aimed to systematically review literature pertaining to HSC based tissue engineering strategies in animal models of chondral repair such that trends may be identified and the utility of HSCs in chondral repair can be elucidated. An extensive search strategy was carried out through PubMed, MEDLINE, and EMBASE databases to identify relevant studies. Initially the title and abstract of 787 studies were screened after which inclusion and exclusion criteria sorted 56 studies for full-text evaluation. Following full text review, a final number of 22 articles were included. Out of 22 included studies, 16 used scaffold implantation, 2 used cell pellet implantation, and 4 used intra-articular injection to administer HSCs to the region of chondral defects. HSC-containing implants outperformed scaffold-only or untreated control groups in both large and small animals for chondral regeneration. Umbilical cord mesenchymal stem cells and hyaluronic acid-containing scaffolds emerged as popular stem cell and scaffold choices, respectively. However, the short analysis timepoints post cell implantation was a key limitation in many studies. This review highlights the versatility of HSCs in achieving chondral regeneration in vivo and the enhancement of chondral repair through the selection of appropriate three-dimensional scaffolds and growth factors which are essential to support cell growth, attachment, migration, and extracellular matrix synthesis. Considerable heterogeneity exists in outcome reporting, and only one article reported biomechanical evaluation of neocartilage. Standardized outcome reporting systems that include comprehensive biomechanical testing protocols should be utilized in future in vivo studies of cartilage tissue engineering as the biomechanical quality of neocartilage is of great functional significance.

Evaluation of autologous adipose-derived mesenchymal stem cell therapy in focal chondral defects of the knee: a pilot case series

Aim: To evaluate the safety, pain, functional and structural improvements after autologous adipose-derived mesenchymal stem cell (ADMSC) therapy in combination with arthroscopic abrasion arthroplasty in focal chondral defects of the knee. Methods: Eight patients with a focal full thickness chondral defect of the knee underwent arthroscopic abrasion arthroplasty followed by postoperative intra-articular injections of autologous ADMSCs (50 × 10⁶ ADMSCs at baseline and 6 months). Clinical outcome was assessed using numeric pain rating scale, Knee Injury and Osteoarthritis Outcome Score and the Western Ontario and McMaster Universities Osteoarthritis Index. Structural outcome was determined by magnetic resonance imaging. Outcome was assessed over 24 months. Results: No serious adverse events occurred. Participants observed clinically significant improvement in pain and function. Magnetic resonance imaging analysis showed cartilage regeneration with T2 mapping values comparable to hyaline cartilage. Conclusion: Arthroscopic abrasion arthroplasty in combination with intra-articular ADMSC therapy results in reproducible pain, functional and structural improvements with regeneration of hyaline-like cartilage. Trial registration number: ACTRN12617000638336.

Better Clinicoradiological Results of BST-CarGel Treatment in Cartilage Repair Compared With Microfracture in Acetabular Chondral Defects at 2 Years

BACKGROUND

BST-CarGel (CarGel) is an injectable chitosan scaffold that is mixed with fresh, autologous blood and injected into the site of microfracture (MF) to physically stabilize clots and enhance cartilage repair.

PURPOSE

To evaluate short-term clinicoradiological outcomes of patients treated arthroscopically for acetabular chondral defects with CarGel in conjunction with MF compared with those treated with MF alone.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

All patients who underwent hip arthroscopy and received MF with or without CarGel for acetabular chondral defects between 2014 and 2018 with a minimum 2-year clinicoradiological follow-up were included. Intraoperative details, postoperative complications, and clinical outcome scores, including the international Hip Outcome Tool-33 (iHOT-33), Hip Outcome Score (HOS)-Activities of Daily Living (HOS-ADL), and Hip Outcome Score-Sports Profile, were analyzed. Serial plain radiographs were assessed independently by 2 blinded observers. A survival analysis was performed to identify the number of cases converted to total hip arthroplasty (THA) in both groups, which was correlated with the cartilage defect size at the time of surgery.

RESULTS

Eighty patients (54 CarGel and 26 MF) were evaluated, including 56 men (70%) and 48 right hips (60%). Three patients were lost to follow-up. There were no major adverse events in either group. The average defect size was 3.63 and 4.97 cm² in MF and CarGel, respectively (P = .002). There was a statistically significant improvement in iHOT-33 (from 43.24 to 60.17 in MF and from 41.13 to 58.39 in CarGel) and HOS-ADL (from 62.25 to 76.75 in MF and from 44.69 to 79.16 in CarGel) scores. There was no difference between the 2 groups in the outcome scores after adjusting for covariates. Survival analysis showed 34.6% of MF cases and 5.9% of CarGel cases were converted to THA (P = .001). The mean defect size of the failure group was higher in CarGel than in MF (8.83 and 3.72 cm², respectively). Mean joint space reduction was 1.41 mm in MF and 0.19 mm in CarGel (P < .001).

CONCLUSION

Two-year clinicoradiological results were promising in these lesions that are difficult to treat. Arthroscopic treatment of chondral acetabular defects with CarGel demonstrated a significant decrease in progressive loss of joint space and conversion to THA compared with MF as an isolated procedure.

The Use of Bone Marrow Concentrate in the Treatment of Full-Thickness Chondral Defects

This article is a critical analysis of a study, "Minimally Manipulated Bone Marrow Concentrate Compared with Microfracture Treatment of Full-Thickness Chondral Defects: A One-Year Study in an Equine Model," by Chu et al. (J Bone Joint Surg Am. 100(2):138-146, 2018). The investigation compared two interventions in the management of full-thickness chondral defects in an equine model: autologous bone marrow concentrate without concomitant microfracture treatment versus microfracture treatment alone. This review analyzes the methodology and results of their investigation and examines how their findings may influence the continued development of therapeutic options for full-thickness cartilage injuries. The study utilized in vitro analysis, arthroscopic assessment, magnetic resonance imaging (MRI) evaluation, and histological analysis to compare the treatments and their influence on the quality of cartilage repair. Although Chu et al. reported similar results between groups, their findings offer insight into the role of arthroscopy, MRI, and histology in the evaluation of repair quality. We compare their findings to those of similar investigations, highlighting the limited therapeutic options and variable clinical outcomes related to the treatment of full-thickness articular cartilage defects.

A Preliminary Study Comparing Microfracture and Local Adherent Transplantation of Autologous Adipose-Derived Stem Cells Followed by Intraarticular Injection of Platelet-Rich Plasma for the Treatment of Chondral Defects in Rabbits

Objective This study aimed to compare microfracture and application of adipose-derived stem cells (ADSCs) by local adherent technique enhanced by platelet-rich plasma (PRP) to provide a new approach for the repair of cartilage defect. Design Full-thickness cylindrical defects were created in the medial femoral condyle in 9 New Zealand White rabbits (5 months old, 4.65 ± 0.20 kg). Two groups of rabbits ( n = 3) were either treated with ADSCs (Group 1) or the microfracture technique (Group 2) following intraarticular injection of PRP 3 times in weekly intervals. Rabbits in control group ( n = 3) remained untreated. The outcome was assessed macroscopically, histologically, and immunohistochemically. Results At the end of week 12, Group 1 showed better defect filling compared with Group 2. Specimens treated with the combination of ADSCs and PRP exhibited significant differences from the other groups in all criteria of International Cartilage Repair Society macroscopic scoring system. Conclusions Intraarticular injection of autologous PRP in combination with transplantation of autologous ADSCs by local adherent technique enhances the quality of cartilage defect repair with better results in comparison with microfracture surgery in a rabbit model.

Safety Profile and Short-term Outcomes of BST-CarGel as an Adjunct to Microfracture for the Treatment of Chondral Lesions of the Hip

Background

Acetabular cartilage lesions are a common abnormality found in patients undergoing hip arthroscopic surgery and may cause pain and functional limitations. Several strategies have been developed to treat chondral defects, with no overwhelming success. Recently, BST-CarGel has gained interest as a scaffolding material that can be injected into the microfracture site to stabilize the clot and facilitate cartilage repair.

Purpose

To perform a retrospective analysis of prospectively collected data to evaluate the safety profile and short-term clinical and radiographic outcomes of patients treated arthroscopically with BST-CarGel for acetabular chondral defects in conjunction with microfracture.

Study Design

Case series; Level of evidence, 4.

Methods

A retrospective chart review was performed on all patients who underwent hip arthroscopic surgery by the senior surgeon to identify those who had BST-CarGel applied to their hip from November 2014 to July 2016, and basic demographic information for those patients was obtained. Operative reports and patient charts were reviewed to assess intraoperative and postoperative complications as well as to obtain the details of surgery, including lesion size and treatment method of the labrum (repair vs reconstruction). All patients filled out self-reported questionnaires, including the international Hip Outcome Tool (iHOT), Hip Outcome Score-Activities of Daily Living (HOS-ADL), and Hip Outcome Score-Sports Profile (HOS-SP) at the time of consultation and at 1 year postoperatively, and results were used to assess the clinical outcomes of surgery.

Results

Thirty-seven patients (37 hips) with a mean age of 36.19 years at the time of the index procedure were evaluated. There were 30 male patients, and 20 procedures were performed on the right hip. The minimum follow-up was 1 year, with a mean follow-up of 12.72 months. There were no major adverse events of deep vein thrombosis, blood vessel or nerve damage, hemarthrosis, arthralgia, or device-related adverse events. Two patients (5.4%) were readmitted because of pain, probably resulting from an inflammatory reaction to BST-CarGel. At 1 year postoperatively, there were statistically significant improvements in the iHOT (40.4 to 59.1; P < .001), HOS-ADL (60.6 to 71.4; P = .02), and HOS-SP (36.9 to 51.6; P = .01) scores. When the patients were subdivided based on the chondral defect size, the iHOT score improved for all chondral defect sizes, and the HOS-SP score improved in patients with medium (2-4 cm²) and very large (>6 cm²) chondral defects. In addition, the iHOT score improved whether the patients had their labrum repaired or reconstructed (P < .001 and P = .02, respectively).

Conclusion

The arthroscopic treatment of chondral acetabular defects with BST-CarGel demonstrates a satisfactory safety profile, with statistically significant improvement in patient-reported clinical outcome scores, even for those with very large chondral defect sizes.

Acetabular Focal Chondral Lesions Are Not Associated With Worse Outcomes After Periacetabular Osteotomy: A Matched Group Analyses

BACKGROUND

The purpose of this study was to assess the outcomes of patients who underwent combined hip arthroscopy and periacetabular osteotomy with acetabular focal chondral defects and compare these outcomes with a group of patients without focal chondral defects.

METHODS

A retrospective review looking at patients who underwent hip arthroscopy and/or periacetabular osteotomy was performed. Minimum 2-year follow-up, Tönnis grade 0-1, and a Beck chondromalacia stages 4-5 were included. Twenty-eight hips met inclusion criteria. These patients were then matched 1:1 and compared.

RESULTS

The average acetabular chondral defect size was 144.3 mm² ± standard deviation 116.2. Postoperative, modified Harris Hip Score, Hip Disability and Osteoarthritis Outcome Score, and University of California Los Angeles scores were similar between groups (P = .382, P = .755, P = .763, respectively). At the last follow-up, Tönnis grade was similar between groups (P = .552). No association between having a defect and increased risk of failure was noted (hazard ratio 1.35 [95% CI 0.43-4.24], P = .607).

CONCLUSION

We found that patients with focal chondral defects did similar to a comparison group of patients without chondral defects.

The Effect of Growth Hormone on Chondral Defect Repair

Objective Focal chondral defects alter joint mechanics and cause pain and debilitation. Microfracture is a surgical technique used to treat such defects. This technique involves penetration of subchondral bone to release progenitor cells and growth factors from the marrow to promote cartilage regeneration. Often this results in fibrocartilage formation rather than structured hyaline cartilage. Some reports have suggested use of growth hormone (GH) with microfracture to augment cartilage regeneration. Our objective was to test whether intra-articular (IA) GH in conjunction with microfracture, improves cartilage repair in a rabbit chondral defect model. We hypothesized that GH would exhibit a dose-dependent improvement in regeneration. Design Sixteen New Zealand white rabbits received bilateral femoral chondral defects and standardized microfracture repair. One group of animals ( n = 8) received low-dose GH by IA injection in the left knee, and the other group ( n = 8) received high-dose GH in the same manner. All animals received IA injection of saline in the contralateral knee as control. Serum assays, macroscopic grading, and histological analyses were used to assess any improvements in cartilage repair. Results Peripheral serum GH was not elevated postoperatively ( P = 0.21). There was no improvement in macroscopic grading scores among either of the GH dosages ( P = 0.83). Scoring of safranin-O-stained sections showed no improvement in cartilage regeneration and some evidence of increased bone formation in the GH-treated knees. Conclusions Treatment with either low- or high-dose IA GH does not appear to enhance short-term repair in a rabbit chondral defect model.

A Comparison of 2-Year Outcomes in Patients Undergoing Tibiofemoral or Patellofemoral Matrix-Induced Autologous Chondrocyte Implantation

BACKGROUND

Matrix-induced autologous chondrocyte implantation (MACI) has demonstrated encouraging clinical results in the treatment of knee chondral defects. However, earlier studies suggested that chondrocyte implantation in the patellofemoral (PF) joint was less effective than in the tibiofemoral (TF) joint.

PURPOSE

To compare the radiological and clinical outcomes of those undergoing MACI to either the femoral condyles or PF joint.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A total of 194 patients were included in this analysis, including 127 undergoing MACI to the medial (n = 94) and lateral (n = 33) femoral condyle, as well as 67 to the patella (n = 35) or trochlea (n = 32). All patients were evaluated clinically (Knee injury and Osteoarthritis Outcome Score [KOOS], visual analog scale, Short Form-36) before surgery and at 3, 12, and 24 months after surgery, while magnetic resonance imaging (MRI) was undertaken at 3, 12, and 24 months, with the MOCART (magnetic resonance observation of cartilage repair tissue) scoring system employed to evaluate the quality and quantity of repair tissue, as well as an MRI composite score. Patient satisfaction was evaluated.

RESULTS

No significant group differences ( P > .05) were seen in demographics, defect size, prior injury, or surgical history, while the majority of clinical scores were similar preoperatively. All clinical scores significantly improved over time ( P < .05), with a significant group effect observed for KOOS activities of daily living ( P = .008), quality of life ( P = .008), and sport ( P = .017), reflecting better postoperative scores in the TF group. While the PF group had significantly lower values at baseline for the KOOS activities of daily living and quality of life subscales, it actually displayed a similar net improvement over time compared with the TF group. At 24 months, 93.7% (n = 119) and 91.0% (n = 61) of patients were satisfied with the ability of MACI to relieve their knee pain, 74.0% (n = 94) and 65.7% (n = 44) with their ability to participate in sport, and 90.5% (n = 115) and 83.6% (n = 56) satisfied overall, in the TF and PF groups, respectively. MRI evaluation via the MOCART score revealed a significant time effect ( P < .05) for the MRI composite score and graft infill over the 24-month period. While subchondral lamina scored significantly better ( P = .002) in the TF group, subchondral bone scored significantly worse ( P < .001). At 24 months, the overall MRI composite score was classified as good/excellent in 98 TF patients (77%) and 54 PF patients (81%).

CONCLUSION

MACI in the PF joint with concurrent correction of PF maltracking if required leads to similar clinical and radiological outcomes compared with MACI on the femoral condyles.

A Registry for Evaluation of Efficiency and Safety of Surgical Treatment of Cartilage Defects: The German Cartilage Registry (KnorpelRegister DGOU)

Background

The need for documentation in cartilage defects is as obvious as in other medical specialties. Cartilage defects can cause significant pain, and lead to reduced quality of life and loss of function of the affected joint. The risk of developing osteoarthritis is high. Therefore, the socioeconomic burden of cartilage defects should not be underestimated.

Objective

The objective of our study was to implement and maintain a registry of all patients undergoing surgical treatment of cartilage defects.

Methods

We designed this multicenter registry for adults whose cartilage defects of a knee, ankle, or hip joint are treated surgically. The registry consists of two parts: one for the physician and one for the patient. Data for both parts will be gathered at baseline and at 6-, 12-, 24-, 36-, 60-, and 120-month follow-ups.

Results

To date, a wide range of German, Swiss, and Austrian trial sites are taking part in the German Cartilage Registry, soon to be followed by further sites. More than 2124 (as of January 31, 2016) cases are already documented and the first publications have been released.

Conclusions

The German Cartilage Registry addresses fundamental issues regarding the current medical care situation of patients with cartilage defects of knee, ankle, and hip joints. In addition, the registry will help to identify various procedure-specific complications, along with putative advantages and disadvantages of different chondrocyte products. It provides an expanding large-scale, unselected, standardized database for cost and care research for further retrospective studies.

Trial Registration

German Clinical Trials Register: DRKS00005617; https://drks-neu.uniklinik-freiburg.de/ drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00005617 (Archived by WebCite at http://www.webcitation.org/6hbFqSws0)

Humeral Chondral Defect and Labral Tear Associated with Paraglenoid Labral Cyst: A Case Report

OBJECTIVE

To report an unusual combination of paraglenoid labral cyst and labral tear with chondral defect of the humeral head.

CLINICAL PRESENTATION AND INTERVENTION

A 34-year-old man presented with right shoulder pain. Conventional MR imaging showed paraglenoid labral cyst. MR arthrography revealed a humeral chondral defect and labral tear associated with paraglenoid labral cyst, and a defect of the posterior inferior labrum extending to the superior labrum and humeral chondral defect. The patient underwent arthroscopic surgery.

CONCLUSION

This case showed the importance of MR arthrography in a case that involved an unusual combination of paraglenoid labral cyst and labral tear with chondral defect.

Cartilage Repair With Autologous Bone Marrow Mesenchymal Stem Cell Transplantation: Review of Preclinical and Clinical Studies

Clinical trials of various procedures, including bone marrow stimulation, mosaicplasty, and autologous chondrocyte implantation, have been explored to treat articular cartilage defects. However, all of them have some demerits. We focused on autologous culture-expanded bone marrow mesenchymal stem cells (BMSC), which can proliferate without losing their capacity for differentiation. First, we transplanted BMSC into the defective articular cartilage of rabbit and succeeded in regenerating osteochondral tissue. We then applied this transplantation in humans. Our previous reports showed that treatment with BMSC relieves the clinical symptoms of chondral defects in the knee and elbow joint. We investigated the efficacy of BMSC for osteoarthritic knee treated with high tibial osteotomy, by comparing 12 BMSC-transplanted patients with 12 cell-free patients. At 16-month follow-up, although the difference in clinical improvement between both groups was not significant, the arthroscopic and histological grading score was better in the cell-transplanted group. At the over 10-year follow-up, Hospital for Special Surgery knee scores improved to 76 and 73 in the BMSC-transplanted and cell-free groups, respectively, which were better than preoperative scores. Additionally, neither tumors nor infections were observed in all patients, and in the clinical study, we have never observed hypertrophy of repaired tissue, thereby guaranteeing the clinical safety of this therapy. Although we have never observed calcification above the tidemark in rabbit model and human histologically, the repair cartilage was not completely hyaline cartilage. To elucidate the optimum conditions for cell therapy, other stem cells, culture conditions, growth factors, and gene transfection methods should be explored.

Durability of partial humeral head resurfacing

BACKGROUND

Partial humeral head resurfacing arthroplasty uses a stemless device, which conserves bone and restores normal anatomy. We hypothesized that this does not offer a reasonable alternative to full resurfacing or total shoulder arthroplasty.

METHODS

We performed a retrospective study of 39 shoulders with focal chondral defects of the humeral head treated with partial resurfacing arthroplasty. A minimum of 2 years' follow-up was reported, unless failure and operative intervention superseded this duration. The mean follow-up period was 51.3 months. The mean age was 45.6 years (range, 27-76 years). Preoperative and postoperative evaluation included history, physical examination, radiographs, and clinical scoring with the American Shoulder and Elbow Surgeons Shoulder Score Index and Subjective Shoulder Value.

RESULTS

Of the 39 shoulders, 25 (64.1%) showed functional improvement and decreased pain. Significant mean improvements were observed in forward flexion (121° to 152°, P = .002), external rotation (37° to 58°, P = .0003), mean Subjective Shoulder Value (31% to 74%, P < .0001), and ASES score (29 to 70, P < .0001). However, at a mean of 26.6 months' follow-up, the failure group included 6 patients (15.3%) who underwent revision and another 4 (10.2%) who were recommended to undergo revision. Patients with no prior or concomitant procedures were rare (n = 5) but had the most reliable outcomes with partial resurfacing, with no failures in that group. Of the 24 patients with prior procedures, 5 had undergone revision, and the clinical outcome scores for the remaining patients were consistently lower than those seen in patients without prior procedures.

CONCLUSION

Concomitant pathology and prior or concomitant surgical procedures potentially impair the outcome of the resurfacing procedure and could be a contraindication. Long-term success remains guarded with this treatment modality, especially in patients whose chondral injury is not an isolated finding.

Incidence and treatment of intra-articular lesions associated with anterior cruciate ligament tears

The aim of the study is to retrospectively review the patients admitted and treated in the “Alexandru Rădulescu” Orthopedics and Traumatology Clinic, Cluj-Napoca for an anterior cruciate ligament tear over a 2-year period and document the intra-articular lesions found at arthroscopy as well as the treatment used for these associated lesions.

Homing and reparative effect of intra-articular injection of autologus mesenchymal stem cells in osteoarthritic animal model

BACKGROUND

This work aimed to study the homing evidence and the reparative effect of mesenchymal stem cells (MSCs) in the healing process of induced osteoarthritis in experimental animal model (donkeys).

METHODS

Twenty-seven donkeys were equally divided into 3 groups based on the observation period after induction of arthritis (3, 6 and 9 weeks) to achieve different degrees of osteoarthritis. Each group was subdivided into three subgroups of three animals each based on the follow-up period (1, 2 and 6 months) after treatment. The induction was done through intra-articular (IA) injection of 2 ml of Amphotericin-B in both carpal joints. MSCs were harvested in a separate procedure, labeled with green fluorescent protein (GFP) using monster GFP vector and suspended in hyaluronic acid for IA injection. Treatment approaches consisted of cell-treatment using MSCs suspended in 3 ml of hyaluronic acid (HA) for the right carpal joint; and using the same amount of (HA) but without MSCs for the left contralateral carpal joint to serve as a control. Animals were assessed clinically and radiologically before and after treatment. Synovial fluid was also evaluated. Histopathologically; articular cartilage structural changes, reduction of articular cartilage matrix staining, osteophyte formation, and subchondral bone plate thickening were graded. Data was summarized using median and percentile for scores of histopathologic grading. Comparison between groups was done using non-parametric Mann Whitney test.

RESULTS

The reparative effect of MSCs was significant both clinically and radiologically in all treated groups (P < 0.05) compared to the control groups. Fluorescence microscopy of sections of the cell-treated joints of all animals indicated that the GFP-transduced injected cells have participated effectively in the reparative process of the damaged articular surface and have integrated within the existing articular cartilage. The cells were associated with the surface of the cartilage and, were also detected in the interior.

CONCLUSIONS

Homing was confirmed by the incorporation of injected GFP-labeled MSCs within the repaired newly formed cartilage. Significant recovery proves that the use of IA injection of autologous MSCs is a viable and a practical option for treating different degrees of osteoarthritis.