Seven-Year Follow-up of Matrix-Induced Autologous Implantation in Talus Articular Defects

Clinical Applicability of Autologous Chondrocyte Implantation for the Treatment of Osteochondral Defects: A Meta-analysis

PURPOSE

Osteoarthritis and other joint disorders are the leading cause of disability in the elderly and the treatment of joint lesions is challenging. Autologous chondrocyte implantation (ACI) has been reported with variable effects for the treatment of osteochondral and other joint lesions. In this study, we performed a meta-analysis of the recent literature to determine the clinical applicability of ACI for osteochondral defects.

METHODS

A meta-analysis was performed on the recent literature showing the effects of ACI on osteochondral defects. The PUBMED, ScienceDirect and Google Scholar databases were used to identify eligible studies from Jan 2010 to Sep 2022. Both fixed and random models of meta-analysis were applied with all reported scoring systems to quantify the effectiveness of ACI on osteochondral defects.

RESULTS

The pool data of 965 patients as a case series after ACI from a fixed model showed a significant improvement in the osteochondral defects (odds ratio = 8.75, 95%CI = 7.127 to 10.743, p = 0.000). These results were further verified by a random model of meta-analysis. The data also showed a substantial heterogeneity among the studies used in the meta-analysis (Q-value = 160.41, I-squared = 87.53, p = 0.000). Furthermore, this meta-analysis also compared different ACI procedures with different scoring systems but the overall outcome remains the same as ACI was found to be useful for the healing of the osteochondral defects.

CONCLUSION

This meta-analysis of 965 case series revealed that the ACI markedly improved the damage osteochondral defects scores but the optimal treatment is still controversial, therefore further studies are needed to validate these findings in a clinical setting.

Retrograde Autologous Talar Osteocancellous Bone Grafting for the Treatment of Osteochondral Lesions of the Talus: A Technical Note

Osteochondral lesions of the talus (OLT) are common injuries in young athletes. Various kinds of surgical procedures are available for orthopaedic surgeons, but which surgical technique is the best remains controversial. Many surgical procedures require malleolar osteotomy to obtain appropriate surgical exposure to the OLT because of the anatomic characteristics of the ankle joint. However, malleolar osteotomy is invasive and has a potential risk of complications, such as tibial chondral damage and pseudoarthrosis. This article aims to introduce a novel surgical procedure for the treatment of OLTs: retrograde autologous talar osteocancellous bone grafting without the need for osteotomy and harvesting a graft from anywhere other than the talus. First, an arthroscopic evaluation is performed to verify the location, size, and cartilage quality of the OLT as well as concomitant lesions. After confirming the position of the guide pin using a guide device arthroscopically, a talar osteocancellous bone plug is harvested using a coring reamer. The OLT of the harvested talar bone plug is removed, and under arthroscopy, the talar osteocancellous bone plug is retrogradely inserted into the talar bone tunnel. To stabilize the implanted bone plug, one or two bioabsorbable pins are inserted from the lateral wall of the talus while applying counterforce to the articular surface of the bone plug. The present surgical technique can minimally invasively address the OLT without the need for malleolar osteotomy and harvesting a graft from the knee joint or iliac bone.

Efficacy and safety of autologous chondrocyte implantation for osteochondral defects of the talus: a systematic review and meta-analysis

INTRODUCTION

Studies have reported various effects of autologous chondrocyte implantation (ACI) on osteochondral defects of the talus. Therefore, to assess the effectiveness of ACI for osteochondral defects of the talus, we used the meta-analytic approach.

MATERIALS AND METHODS

Electronic databases PubMed, Embase, and the Cochrane Library were systematically searched to identify eligible studies from their inception until November 2020. The random-effects model was used to calculate the incidence of success rate and American Orthopaedic Foot and Ankle Society (AOFAS) score for patients after ACI treatment. Subgroup analyses were also conducted based on age, technique, indication, size, and follow-up duration.

RESULTS

For the final meta-analysis, we selected 23 case series studies with a total of 458 patients with osteochondral defects of the talus. Overall, after ACI for patients with osteochondral defects of the talus, we noted that the incidence of success rate was 89% (95% confidence interval (95% CI) 85%-92%; P < 0.001). Moreover, after ACI for patients with osteochondral defects of the talus, the AOFAS score was 86.33 (95% CI 83.33-89.33; P < 0.001). Subgroup analysis showed that the AOFAS score after ACI is significantly different when stratified by the mean age of the patients (P = 0.006).

CONCLUSIONS

This study revealed that the use of ACI could provide a relatively high success rate and improve the AOFAS score for patients with osteochondral defects of the talus, which should be recommended in clinical practice.

Prognostic factors for the management of chondral defects of the knee and ankle joint: a systematic review

Purpose

Different surgical techniques to manage cartilage defects are available, including microfracture (MFx), autologous chondrocyte implantation (ACI), osteoarticular auto- or allograft transplantation (OAT), autologous matrix-induced chondrogenesis (AMIC). This study investigated the patient-related prognostic factors on the clinical outcomes of surgically treated knee and ankle cartilage defects.

Methods

This study followed the PRISMA statement. In May 2022, the following databases were accessed: PubMed, Google Scholar, Embase, and Scopus. All the studies investigating the outcomes of surgical management for knee and/or talus chondral defects were accessed. Only studies performing mesenchymal stem cells transplantation, OAT, MFx, ACI, and AMIC were considered. A multiple linear model regression analysis through the Pearson Product–Moment Correlation Coefficient was used.

Results

Data from 184 articles (8905 procedures) were retrieved. Female sex showed a positive moderate association with visual analogue scale at last follow-up (P = 0.02). Patient age had a negative association with the American Orthopaedic Foot and Ankle Score (P = 0.04) and Lysholm Knee Scoring Scale (P = 0.03). BMI was strongly associated with graft hypertrophy (P = 0.01). Greater values of VAS at baseline negatively correlate with lower values of Tegner Activity Scale at last follow-up (P < 0.0001).

Conclusion

The clinical outcomes were mostly related to the patients’ performance status prior surgery. A greater BMI was associated with greater rate of hypertrophy. Female sex and older age evidenced fair influence, while symptom duration prior to the surgical intervention and cartilage defect size evidenced no association with the surgical outcome. Lesion size and symptom duration did not evidence any association with the surgical outcome.

Fibrin glue does not assist migration and proliferation of chondrocytes in collagenic membranes: an in vitro study

Background

Some authors secured the membrane during matrix-induced autologous chondrocyte implantation (mACI) with fibrin glue or did not use a formal fixation. The real impact of fibrin glue addition on chondrocytes migration and proliferation has not yet been clarified. This study evaluated the impact of fibrin glue on a chondrocyte loaded collagenic membrane.

Methods

A resorbable collagen I/III porcine derived membrane commonly employed in AMIC was used for all experiments. Chondrocytes from three difference donors were used. At 1-, 2-, 3-, 4-, 6-, and at 8-week the membranes were embedded in Mounting Medium with Dapi (ABCAM, Cambridge, UK). The Dapi contained in the mounting medium ties the DNA of the cell nucleus and emits a blue fluorescence. In this way, the spreading of the cells in the membrane can be easily monitored. The outcomes of interest were to evaluate (1) cell migration and (2) cell proliferation within the porous membrane layer. DAPI/nuclei signals were analysed with fluorescence microscope under a magnification of 100-fold.

Results

The no-fibrin group demonstrated greater migration of the cells within the membrane. Although migration resulted higher in the no-fibrin group at every follow-up, this difference was significant only at week 1 (P < 0.001), 2 (P = 0.004), and 3 (P = 0.03). No difference was found at week 3, 6, and 8. The no-fibrin group demonstrated greater proliferation of the chondrocytes within the membrane. These differences were significant at week 4 (P < 0.0001), 6 (P < 0.0001), 8 (P < 0.0001).

Conclusion

The use of fibrin glue over a resorbable membrane leads to lower in vitro proliferation and migration of chondrocytes.

AMIC for traumatic focal osteochondral defect of the talar shoulder: a 5 years follow-up prospective cohort study

BACKGROUND

Autologous Matrix-Induced Chondrogenesis (AMIC) is addressed to osteochondral defects of the talus. However, evidence concerning the midterm efficacy and safety of AMIC are limited. This study assessed reliability and feasibility of AMIC at 60 months follow-up. We hypothesize that AMIC leads to good clinical outcome at midterm follow-up.

METHODS

Surgeries were approached with an arthrotomy via malleolar osteotomy. A resorbable porcine I/III collagen membrane (Chondro-Gide®, Geistlich Pharma AG, Wolhusen, Switzerland) was used. Patients were followed at 24 and 60 months. The primary outcome of interest was to analyse the Foot Function Index (FFI), and the subscale hindfoot of the American Orthopaedic Foot and Ankle Score (AOFAS). Complications such as failure, revision surgeries, graft delamination, and hypertrophy were also recorded. The secondary outcome of interest was to investigate the association between the clinical outcome and patient characteristics at admission.

RESULTS

Data from 19 patients were included. The mean age at admission was 47.3 ± 13.2 years, and the mean BMI 24.1 ± 4.9 kg/m². 53% (10 of 19 patients) were female. At a mean of 66.2 ± 11.6 months, the FFI decreased at 24-months follow-up of 22.5% (P = 0.003) and of further 1.3% (P = 0.8) at 60-months follow-up. AOFAS increased at 24-months follow-up of 17.2% (P = 0.003) and of further 3.4 (P = 0.2) at 60-months follow-up. There were two symptomatic recurrences within the follow-up in two patients. There was evidence of a strong positive association between FFI and AOFAS at baseline and the same scores last follow-up (P = 0.001 and P = 0.0002, respectively).

CONCLUSION

AMIC enhanced with cancellous bone graft demonstrated efficacy and feasibility for osteochondral defects of the talus at five years follow-up. The greatest improvement was evidenced within the first two years. These results suggest that clinical outcome is influenced by the preoperative status of the ankle. High quality studies involving a larger sample size are required to detect seldom complications and identify prognostic factors leading to better clinical outcome.

LEVEL OF EVIDENCE

II, prospective cohort study.

Osteochondritis Dissecans: Current Understanding of Epidemiology, Etiology, Management, and Outcomes

➤

Osteochondritis dissecans occurs most frequently in the active pediatric and young adult populations, commonly affecting the knee, elbow, or ankle, and may lead to premature osteoarthritis.

➤

While generally considered an idiopathic phenomenon, various etiopathogenetic theories are being investigated, including local ischemia, aberrant endochondral ossification of the secondary subarticular physis, repetitive microtrauma, and genetic predisposition.

➤

Diagnosis is based on the history, physical examination, radiography, and advanced imaging, with elbow ultrasonography and novel magnetic resonance imaging protocols potentially enabling early detection and in-depth staging.

➤

Treatment largely depends on skeletal maturity and lesion stability, defined by the presence or absence of articular cartilage fracture and subchondral bone separation, as determined by imaging and arthroscopy, and is typically nonoperative for stable lesions in skeletally immature patients and operative for those who have had failure of conservative management or have unstable lesions.

➤

Clinical practice guidelines have been limited by a paucity of high-level evidence, but a multicenter effort is ongoing to develop accurate and reliable classification systems and multimodal decision-making algorithms with prognostic value.

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.

Midterm Results of Fresh-Frozen Osteochondral Allografting for Osteochondral Lesions of the Talus

BACKGROUND

Osteochondral lesions of the talus (OLT) are relatively common. Following the failure of conservative treatment, many operative options have yielded varied results. In this study, midterm outcomes after fresh-frozen osteochondral allograft transplantation for the treatment of OLT were evaluated.

METHODS

Twenty-five patients (12 women and 13 men) with a mean age 40.4 (range 18-70) years between 2009 and 2014 were enrolled. Of 25 ankles, 3, 13, 4, and 4 were involved with the talus at Raikin zone 3, 4, 6, and 7 as well as one coexisted with zone 4 and 6 lesion. The mean OLT area was 1.82 cm² (range, 1.1-3.0). The mean follow-up period was 5.5 years (range, 4-9.3). Outcomes evaluation included the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, visual analog scale score, and 12-item Short Form Health Survey (SF-12).

RESULT

AOFAS ankle-hindfoot score increased from 74 preoperatively to 94 at 2 years postoperatively (P < .001) and the SF-12 physical health component scores increased from 32 to 46 points (P < .001). Incorporation was inspected in all patients in the latest follow-up, and graft subsidence and radiolucency were observed in 2 and 7 cases, respectively, whereas graft collapse and revision OLT graft were not observed. Bone sclerosis was found in 6 of 25 patients.

CONCLUSION

With respect to midterm results, fresh, frozen-stored allograft transplantation might be an option in the management of symptomatic OLT.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Matrix-Induced Autologous Chondrocyte Implantation (MACI) Grafting for Osteochondral Lesions of the Talus

BACKGROUND

Matrix-induced autologous chondrocyte implantation (MACI) is an established treatment method for larger joints and has shown promising results in the ankle as well. We present a series of patients after ankle MACI with long-term follow-up of clinical and radiological outcomes.

METHODS

We present the follow-up of 15 patients who underwent MACI grafting from August 2003 to February 2006. The mean follow-up was 12.9 years. Clinical evaluations were conducted using the American Orthopaedic Foot & Ankle Society (AOFAS), Foot and Ankle Activity Measurement (FAAM), and visual analog scale (VAS) scoring systems and the magnetic resonance observation of cartilage repair tissue (MOCART) scoring system for radiological evaluation.

RESULTS

The mean size of the talar osteochondral defects was 204 mm². We found a significant improvement in mean AOFAS score from 60 preoperatively to a mean of 84 at 12 years postoperatively. The 12-year FAAM score for Activities of Daily Living was 89% (range, 62%-99%). The mean 12-year MOCART score was 65 points (range, 30-100 points) with significant agreement between assessors (P < .001). However, the MOCART scores did not correlate with the FAAM scores (P = .86).

CONCLUSION

Considering our long-term follow-up, we believe MACI is a reliable treatment method for talar osteochondral defects providing lasting pain relief and satisfying clinical results. However, with an equivalent outcome, but at higher costs, and the requirement for 2 operative procedures, the results do not seem to be superior to other established methods. The clinical utility of the MOCART score requires further scrutiny since we were not able to show any correlation between the score and clinical outcome.

LEVEL OF EVIDENCE

Level IV, case series.

Viscoelasticity of hydrazone crosslinked poly(ethylene glycol) hydrogels directs chondrocyte morphology during mechanical deformation

Chondrocyte deformation influences disease progression and tissue regeneration in load-bearing joints. In this work, we found that viscoelasticity of dynamic covalent crosslinks temporally modulates the biophysical transmission of physiologically relevant compressive strains to encapsulated chondrocytes. Chondrocytes in viscoelastic alky-hydrazone hydrogels demonstrated (91.4 ± 4.5%) recovery of native rounded morphologies during mechanical deformation, whereas primarily elastic benzyl-hydrazone hydrogels significantly limited morphological recovery (21.2 ± 1.4%).

[Research progress in surgical procedures for osteochondral lesions of talus]

OBJECTIVE

To summarize the research progress of surgical procedures in osteochondral lesions of the talus (OLT).

METHODS

By consulting the related literature of OLT in recent years, the advantages and disadvantages of various surgical treatment schemes were analyzed and summarized.

RESULTS

There are many surgical treatments for OLT, including bone marrow stimulation, osteochondral transplantation, autologous chondrocyte transplantation, and biologically assisted therapy. Various schemes have different indications and limitations. With the continuous development of various technologies, the effectiveness of OLT treatment will gradually improve.

CONCLUSION

There are still many difficulties and controversies in the treatment of OLT, and there is no unified treatment plan. It is suggested that individualized operation plan should be formulated according to the specific conditions of patients.

Evaluation of Different Seeding Methods for Cell-Seeded Collagen Matrix-Supported Autologous Chondrocyte Transplantation

Purpose  The aim of the present study was to evaluate different methods for the intraoperative seeding of chondrocytes on commercially available collagen I/III matrix, in the context of cell-seeded collagen matrix-supported autologous chondrocyte transplantation (ACT-CS).

Methods  Human chondrocytes were enzymatically isolated from cartilage portion of discarded femoral heads of patients who underwent total hip replacement. Chondrocytes were cultured until passage 3, and then used for the experiments. The cells (5.0 × 10 ⁵ ) were suspended in two different volumes, 75 and 250 µL, and seeded on a matrix sample with a surface of 1 cm ² by means of a micropipette. Moreover, the direct immersion of the matrix in the cell suspension was evaluated as a possible protocol for chondrocyte seeding. Cell adhesion was allowed for 10, 30, or 60 minutes in all samples before evaluation.

Results  Data showed that the seeding time did not affect cell viability and distribution, but there was a great difference between the two volumes of injection. In fact, the use of 75 µL significantly reduced cell viability with respect to both 250 µL seeding volume and the immersion protocol. Indeed, cell distribution resulted homogeneous in the samples seeded with the larger volume and with the immersion protocol.

Conclusion  The use of 250 µL/cm ² volume or the immersion protocol for 10 minutes are valuable methods for chondrocyte seeding on collagen matrix in an intraoperative scenario.

Clinical Relevance  The protocol of chondrocyte seeding in ACT-CS is extremely variable among available literature reports. Chondrocytes adhesion to the matrix represents a crucial step in this methodology, and the present study provides in vitro indication for the choice of the seeding protocol in the context of ACT-CS.

Osteochondral Allograft Transplantation for Osteochondral Lesions of the Talus: Midterm Follow-up

BACKGROUND:

Fresh osteochondral allograft (OCA) transplantation represents a biologic restoration technique as an alternative treatment option for larger osteochondral lesions of the talus (OLT). The purpose of this study was to evaluate midterm outcomes after OCA transplantation for the treatment of OLT.

METHODS:

Nineteen patients (20 ankles) received partial unipolar OCA transplant for symptomatic OLT between January 1998 and October 2014. The mean age was 34.7 years, and 53% were male. The average graft size was 3.8 cm². All patients had a minimum follow-up of 2 years. Outcomes included the American Academy of Orthopaedic Surgeons Foot and Ankle Module (AAOS-FAM), the Olerud-Molander Ankle Score (OMAS), and pain and satisfaction questionnaires. Failure of OCA was defined as conversion to arthrodesis or revision OCA transplantation.

RESULTS:

Five of 20 ankles (25%) required further surgery, of which 3 (5%) were considered OCA failures (2 arthrodesis and 1 OCA revision). The mean time to failure was 3.5 (range, 0.9 to 6.7) years. Survivorship was 88.7% at 5 years and 81.3% at 10 years. The median follow-up of the 17 patients with grafts in situ was 9.7 years. The mean OMAS improved significantly from 40 points preoperatively to 71 points postoperatively ( P < .05; range, 5 to 55). The mean postoperative AAOS-FAM core score was 81.5 ± 15 (range, 40.5 to 96.6). Fifteen of 17 patients responded to follow-up questions regarding their ankle; 14 patients reported less pain and better function, and 13 patients were satisfied with the results of the procedure.

CONCLUSION:

Our study of midterm results after OCA transplantations showed that this procedure was a reasonable treatment option for large OLT.

LEVEL OF EVIDENCE:

Level IV, case series.

Hydrazone covalent adaptable networks modulate extracellular matrix deposition for cartilage tissue engineering

Cartilage tissue engineering strategies often rely on hydrogels with fixed covalent crosslinks for chondrocyte encapsulation, yet the resulting material properties are largely elastic and can impede matrix deposition. To address this limitation, hydrazone crosslinked poly(ethylene glycol) hydrogels were formulated to achieve tunable viscoelastic properties and to study how chondrocyte proliferation and matrix deposition vary with the time-dependent material properties of covalent adaptable networks. Hydrazone equilibrium differences were leveraged to produce average stress relaxation times from hours (4.01 × 103 s) to months (2.78 × 106 s) by varying the percentage of alkyl-hydrazone (aHz) and benzyl-hydrazone (bHz) crosslinks. Swelling behavior and degradation associated with adaptability were characterized to quantify temporal network changes that can influence the behavior of encapsulated chondrocytes. After four weeks, mass swelling ratios varied from 36 ± 3 to 17 ± 0.4 and polymer retention ranged from 46 ± 4% to 92 ± 5%, with higher aHz content leading to loss of network connectivity with time. Hydrogels were formulated near the Flory-Stockmayer bHz percolation threshold (17% bHz) to investigate chondrocyte response to distinct levels of covalent architecture adaptability. Four weeks post-encapsulation, formulations with average relaxation times of 3 days (2.6 × 105s) revealed increased cellularity and an interconnected articular cartilage-specific matrix. Chondrocytes embedded in this adaptable formulation (22% bHz) deposited 190 ± 30% more collagen and 140 ± 20% more sulfated glycosaminoglycans compared to the 100% bHz control, which constrained matrix deposition to pericellular space. Collectively, these findings indicate that incorporating highly adaptable aHz crosslinks enhanced regenerative outcomes. However, connected networks containing more stable bHz bonds were required to achieve the highest quality neocartilaginous tissue. STATEMENT OF SIGNIFICANCE: Covalently crosslinked hydrogels provide robust mechanical support for cartilage tissue engineering applications in articulating joints. However, these materials traditionally demonstrate purely elastic responses to deformation despite the dynamic viscoelastic properties of native cartilage tissue. Here, we present hydrazone poly(ethylene glycol) hydrogels with tunable viscoelastic properties and study covalent adaptable networks for cartilage tissue engineering. Using hydrazone equilibrium and Flory-Stockmayer theory we identified average relaxation times leading to enhanced regenerative outcomes and showed that extracellular matrix deposition was biphasic as a function of the hydrazone covalent adaptability. We also showed that the incorporation of highly adaptable covalent crosslinks could improve cellularity of neotissue, but that a percolating network of more stable bonds was required to maintain scaffold integrity and form the highest quality neocartilaginous tissue.