Autologous chondrocyte implantation of the ankle: a 2- to 5-year follow-up

Second-Look Arthroscopy Shows Inferior Cartilage after Bone Marrow Stimulation Compared with Other Operative Techniques for Osteochondral Lesions of the Talus: A Systematic Review and Meta-Analysis

OBJECTIVE

To compare cartilage quality after different surgical interventions for osteochondral lesions of the talus (OLT), evaluated by second-look arthroscopy. Secondary aims were to report concomitant diagnoses, and to correlate cartilage quality with clinical and radiological outcomes. This review hypothesizes that the cartilage repair after bone marrow stimulation (BMS) is inferior to the other available treatment options.

METHODS

PROSPERO ID: CRD42022311489. Studies were retrieved through PubMed, EMBASE (Ovid), and Cochrane Library. Studies were included if they reported cartilage quality after second-look investigation after surgical treatment of OLT. The primary outcome measure was the cartilage quality success and failure rates (%) per surgical intervention group. Correlations between the cartilage quality and clinical or radiological outcomes were calculated.

RESULTS

Twenty-nine studies were included, comprising 586 ankles that had undergone second-look arthroscopy on average 16 months after initial surgery. The success rate for BMS was 57% (95% confidence interval [CI] = 48%-65%), for fixation (FIX) 86% (95% CI = 70%-94%), for osteo(chondral) transplantation (OCT) 91% (95% CI = 80%-96%), for cartilage implementation techniques (CITs) 80% (95% CI = 69%-88%), and for retrograde drilling 100% (95% CI = 66%-100%). The success rate of BMS was significantly lower than FIX, OCT, and CIT (P < 0.01). There were no significant differences between other treatment groups. A moderate positive significant correlation between the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score and the International Cartilage Repair Society score (ICRS) was found (ρ = 0.51, P < 0.001).

CONCLUSIONS

Successful restoration of cartilage quality was found in the majority of surgically treated OLTs. However, BMS yields inferior cartilage quality compared with FIX, OCT, and CIT. Study Design. Systematic review and meta-analysis. Level of evidence. Level IV, systematic review and meta-analysis.

Large variation in postoperative rehabilitation protocols following operative treatment of osteochondral lesions of the talus: A systematic review and meta-analysis on >200 studies

PURPOSE

A treatment-specific rehabilitation protocol and well-defined return-to-play criteria guide clinical decision-making on return to normal function, activity, sports and performance after surgical treatment for osteochondral lesion of the talus (OLT). The optimal rehabilitation protocols in the current literature remain unclear. The purpose of this study was to explore the existing literature on rehabilitation protocols from the early postoperative phase to return to sport onwards after different types of surgical treatment of OLTs.

METHODS

PubMed, Embase, CDSR, DARE and Central were searched systematically from inception to February 2023 according to the PRISMA 2020 guidelines. All clinical studies with a description of postoperative rehabilitation criteria after surgical treatment of OLTs were included. The primary outcome of this study is the extent of reportage for each rehabilitation parameter expressed in percentage. The secondary outcome is the reported median time for each parameter in rehabilitation protocols for all different treatment modalities (type of surgery). The median time, expressed as number of weeks, for each parameter was compared between different types of surgery.

RESULTS

A total of 227 articles were included reporting on 255 different rehabilitation protocols from seven different types of surgery. Weight-bearing instructions were reported in 84%-100% and the use of a cast or walker was prescribed in 27%-100%. Range of motion exercises were described in 54%-100% whereas physical therapy was advised in 21%-67% of the protocols. Any advice on return to sport was described in 0%-67% protocols. A nonparametric analysis of variance showed significant differences between the different surgical treatment modalities for the following parameters between the treatment groups: time to full weight-bearing (p < 0.0003) and return to high impact level of sports (p < 0.0003). Subjective or objective criteria for progression during rehabilitation were reported in only 24% of the studies.

CONCLUSION

An in-depth exploration of the current literature showed substantial variation in postoperative rehabilitation guidelines with an associated underreporting of the most important rehabilitation parameters in postoperative protocols after surgical treatment of OLTs. Furthermore, nearly all rehabilitation protocols were constructed according to a time-based approach. Only one out of four reported either objective or subjective criteria.

LEVEL OF EVIDENCE

Level IV, systematic review.

Cartilage Defect Treatment Using High-Density Autologous Chondrocyte Implantation (HD-ACI)

Hyaline cartilage's inability to self-repair can lead to osteoarthritis and joint replacement. Various treatments, including cell therapy, have been developed for cartilage damage. Autologous chondrocyte implantation (ACI) is considered the best option for focal chondral lesions. In this article, we aimed to create a narrative review that highlights the evolution and enhancement of our chondrocyte implantation technique: High-Density-ACI (HD-ACI) Membrane-assisted Autologous Chondrocyte Implantation (MACI) improved ACI using a collagen membrane as a carrier. However, low cell density in MACI resulted in softer regenerated tissue. HD-ACI was developed to improve MACI, implanting 5 million chondrocytes per cm2, providing higher cell density. In animal models, HD-ACI formed hyaline-like cartilage, while other treatments led to fibrocartilage. HD-ACI was further evaluated in patients with knee or ankle defects and expanded to treat hip lesions and bilateral defects. HD-ACI offers a potential solution for cartilage defects, improving outcomes in regenerative medicine and cell therapy. HD-ACI, with its higher cell density, shows promise for treating chondral defects and advancing cartilage repair in regenerative medicine and cell therapy.

Republication of "Osteochondral Lesions of the Talus: Current Concepts in Diagnosis and Treatment"

Osteochondral lesions of the talus (OLTs) are a difficult pathologic entity to treat. They require a strong plan. Lesion size, location, chronicity, and characteristics such as displacement and the presence of subchondral cysts help dictate the appropriate treatment required to achieve a satisfactory result. In general, operative treatment is reserved for patients with displaced OLTs or for patients who have failed nonoperative treatment for 3 to 6 months. Operative treatments can be broken down into cartilage repair, replacement, and regenerative strategies. There are many promising treatment options, and research is needed to elucidate which are superior to minimize the morbidity from OLTs.

Osteochondral Lesions of the Ankle and Foot

Osteochondral lesions (OCLs) in the ankle are more common than OCLs of the foot, but both share a similar imaging appearance. Knowledge of the various imaging modalities, as well as available surgical techniques, is important for radiologists. We discuss radiographs, ultrasonography, computed tomography, single-photon emission computed tomography/computed tomography, and magnetic resonance imaging to evaluate OCLs. In addition, various surgical techniques used to treat OCLs-debridement, retrograde drilling, microfracture, micronized cartilage-augmented microfracture, autografts, and allografts-are described with an emphasis on postoperative appearance following these techniques.

Retrograde Drilling, Ossoscopy, and Autologous Bone Grafting: An Alternative Technique for Treatment of Osteochondral Lesion of the Talus Stage 2 and 3 in Adults

BACKGROUND

Symptomatic osteochondral lesions of the talus (OLTs) often require surgical intervention. There are various surgical methods. A generally valid, stage-dependent therapeutic algorithm does not exist. The aim of our study is to show long- term results of an alternative technique that combines retrograde drilling, debridement performed under arthroscopic visualization, and autologous bone grafting.

METHODS

The surgical technique was performed in 24 patients with medial or lateral OLTs, and the data were analyzed retrospectively. In our technique, the affected subchondral bone was overdrilled retrogradely and resected under arthroscopic visualization (ossoscopy) without violating the cartilage. The resulting defect was filled with autologous bone from the medial tibia metaphysis. Outcome parameters were the numeric rating scale (NRS), the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, and range of motion (ROM). The Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score was assessed and a possible correlation with the clinical outcome scores was calculated. Data concerning complication rates were also collected.

RESULTS

The mean surface size of the OLTs was 0.9 ± 0.3 cm2. The mean follow-up was 89 months. The AOFAS score improved significantly from 57.7 points preoperatively to 88.8 points at the final follow-up (P < .0001). The pain value measured by the NRS decreased significantly from 8 to a pain level of 2. ROM improved in 37.5% of the patients for dorsiflexion and 29.2% for plantarflexion. There were no significant correlations between the MOCART score and the AOFAS score or the pain value on NRS.

CONCLUSION

Retrograde drilling, ossoscopy, and autologous bone grafting for OLTs is a promising technique with good long-term results. The patients' satisfaction rate, especially in OLT stages 2 and 3, was excellent.

LEVEL OF EVIDENCE

Level IV, case series.

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.

Cartilage regeneration using improved surface electrospun bilayer polycaprolactone scaffolds loaded with transforming growth factor-beta 3 and rabbit muscle-derived stem cells

Polycaprolactone (PCL) has recently received significant attention due to its mechanical strength, low immunogenicity, elasticity, and biodegradability. Therefore, it is perfectly suitable for cartilage tissue engineering. PCL is relatively hydrophobic in nature, so its hydrophilicity needs to be enhanced before its use in scaffolding. In our study, first, we aimed to improve the hydrophilicity properties after the network of the bilayer scaffold was formed by electrospinning. Electrospun bilayer PCL scaffolds were treated with ozone and further loaded with transforming growth factor-beta 3 (TGFβ3). In vitro studies were performed to determine the rabbit muscle-derived stem cells’ (rMDSCs) potential to differentiate into chondrocytes after the cells were seeded onto the scaffolds. Statistically significant results indicated that ozonated (O) scaffolds create a better environment for rMDSCs because collagen-II (Coll2) concentrations at day 21 were higher than non-ozonated (NO) scaffolds. In in vivo studies, we aimed to determine the cartilage regeneration outcomes by macroscopical and microscopical/histological evaluations at 3- and 6-month time-points. The Oswestry Arthroscopy Score (OAS) was the highest at both mentioned time-points using the scaffold loaded with TGFβ3 and rMDSCs. Evaluation of cartilage electromechanical quantitative parameters (QPs) showed significantly better results in cell-treated scaffolds at both 3 and 6 months. Safranin O staining indicated similar results as in macroscopical evaluations—cell-treated scaffolds revealed greater staining with safranin, although an empty defect also showed better results than non-cell-treated scaffolds. The scaffold with chondrocytes represented the best score when the scaffolds were evaluated with the Mankin histological grading scale. However, as in previous in vivo evaluations, cell-treated scaffolds showed better results than non-cell-treated scaffolds. In conclusion, we have investigated that an ozone-treated scaffold containing TGFβ3 with rMDSC is a proper combination and could be a promising scaffold for cartilage regeneration.

Nonoperative and Operative Soft-Tissue and Cartilage Regeneration and Orthopaedic Biologics of the Foot and Ankle: An Orthoregeneration Network Foundation Review

Orthoregeneration is defined as a solution for orthopaedic conditions that harnesses the benefits of biology to improve healing, reduce pain, improve function, and optimally, provide an environment for tissue regeneration. Options include drugs, surgical intervention, scaffolds, biologics as a product of cells, and physical and electromagnetic stimuli. The goal of regenerative medicine is to enhance the healing of tissue after musculoskeletal injuries as both isolated treatment and adjunct to surgical management, using novel therapies to improve recovery and outcomes. Various orthopaedic biologics (orthobiologics) have been investigated for the treatment of pathology involving the foot and ankle (including acute traumatic injuries and fractures, tumor, infection, osteochondral lesions, arthritis, and tendinopathy) and procedures, including osteotomy or fusion. Promising and established treatment modalities include 1) bone-based therapies (such as cancellous or cortical autograft from the iliac crest, proximal tibia, and/or calcaneus, fresh-frozen or freeze-dried cortical or cancellous allograft, including demineralized bone matrix putty or powder combined with growth factors, and synthetic bone graft substitutes, such as calcium sulfate, calcium phosphate, tricalcium phosphate, bioactive glasses (often in combination with bone marrow aspirate), and polymers; proteins such as bone morphogenic proteins; and platelet-derived growth factors; 2) cartilage-based therapies such as debridement, bone marrow stimulation (such as microfracture or drilling), scaffold-based techniques (such as autologous chondrocyte implantation [ACI] and matrix-induced ACI, autologous matrix-induced chondrogenesis, matrix-associated stem cell transplantation, particulated juvenile cartilage allograft transplantation, and minced local cartilage cells mixed with fibrin and platelet rich plasma [PRP]); and 3) blood, cell-based, and injectable therapies such as PRP, platelet-poor plasma biomatrix loaded with mesenchymal stromal cells, concentrated bone marrow aspirate, hyaluronic acid, and stem or stromal cell therapy, including mesenchymal stem cell allografts, and adipose tissue-derived stem cells, and micronized adipose tissue injections. LEVEL OF EVIDENCE: Level V, expert opinion.

Management of Treatment Failures in Osteochondral Lesions of the Talus

Osteochondral lesions of the talus are a common result of traumatic ankle injury. Due to the low success rates of nonoperative management, surgical management of osteochondral lesions of the talus (OLTs) has evolved considerably over the past decade as more outcomes research has emerged, new techniques have been described, and we have developed a better understanding of the role of biologics in the treatment algorithm. We describe, in sequence, the surgical management options, including salvage procedures, for failed treatment of OLTs.

Acute Cartilage Injury Induced by Trans-Articular Sutures

OBJECTIVE

To determine the extent of acute cartilage injury by using trans-articular sutures.

METHODS

Five different absorbable sutures, monofilament polydioxanone (PDS) and braided polyglactin (Vicryl), were compared on viable human osteochondral explants. An atraumatic needle with 30 cm of thread was advanced through the cartilage with the final thread left in the tissue. A representative 300 μm transversal slice from the cartilage midportion was stained with Live/Dead probes, scanned under the confocal laser microscope, and analyzed for the diameters of (a) central "Black zone" without any cells, representing in situ thread thickness and (b) "Green zone," including the closest Live cells, representing the maximum injury to the tissue. The exact diameters of suture needles and threads were separately measured under an optical microscope.

RESULTS

The diameters of the Black (from 144 to 219 µm) and the Green zones (from 282 to 487 µm) varied between the different sutures (P < 0.001). The Green/Black zone ratio remained relatively constant (from 1.9 to 2.2; P = 0.767). A positive correlation between thread diameters and PDS suturing material, toward the Black and Green zone, was established, but needle diameters did not reveal any influence on the zones.

CONCLUSIONS

The width of acute cartilage injury induced by the trans-articular sutures is about twice the thread thickness inside of the tissue. Less compressible monofilament PDS induced wider tissue injury in comparison to a softer braided Vicryl. Needle diameter did not correlate to the extent of acute cartilage injury.

Demographics in Patients Receiving Matrix-Assisted Chondrocyte Implantation (MACI) in the Ankle

Objective. To compare demographics and cartilage lesion characteristics of patients enrolled in clinical trials investigating autologous chondrocyte implantation (ACI) in the ankle joint with those actually scheduled for matrix-assisted chondrocyte implantation (MACI) using database records. Design. Anonymized data from patients scheduled for MACI treatment in the ankle in Australia/Asia and Europe were obtained from the Genzyme/Sanofi database. Average age, defect size, and male-female ratio were analyzed and compared by country. A literature search was performed on PubMed and Google Scholar and clinical cohort studies and prospective comparative trials using ACI and related treatments in the ankle joint were identified. Weighted average age, weighted defect size, and male-female ratio were analyzed and compared with database data. Results. The 167 patients included from the databases from Europe and Australia had a mean age of 33.4 years (range 14-64 years) and a mean defect size of 2.27 cm² (range 0.25-16 cm²). Male-female ratio was 4:3. Patients from European countries were significantly younger and had significantly larger defects compared with patients from Australia. From the literature search a total of 472 patients were included from 28 studies. The mean age was 32.2 years (range 15-62 years). Male-female ratio was 3:2. Weighted mean size was 1.94cm² (range 0.3-16). There were no significant differences between previous studies and databases. Conclusion. No differences in sizes and age were found between patients enrolled in clinical trials and patients scheduled for MACI outside clinical trials. The sizes of treated defects followed the general recommendations. There were, however, significant differences between countries.

Long-term Patient-Reported Outcome Measures Following Particulated Juvenile Allograft Cartilage Implantation for Treatment of Difficult Osteochondral Lesions of the Talus

BACKGROUND

Conventional methods are not suitable for difficult to treat osteochondral lesions of the talus (OCLTs). The role of particulated juvenile allograft articular cartilage implantation is not well elucidated for long-term patient outcomes.

METHODS

Thirteen patients with difficult-to-treat OCLTs underwent arthroscopy-assisted implantation of particulated juvenile articular cartilage graft into defects from 2010 to 2012 by the same surgeon. "Difficult to treat" was defined as having at least 3 of the following features or 2 if both variables described lesion characteristics: (1) lesions size of 107 mm² or greater, (2) shoulder lesions, (3) patients who failed microfracture, (4) patient aged ≥40 years, or (5) patient body mass index (BMI) >25. Patients were evaluated using physical examination, patient interviews, and outcome score measures. Patients had follow-up at 2 years, 4 years, and between 6 and 10 years at their most recent follow-up. Differences in functional outcome scores were compared before and after surgery.

RESULTS

Patients (age: 46.5 ± 11.8 years, BMI: 28.5 ± 6.1) had, on average, most recent follow-up of 8.0 years (range 72-113 months). Average visual analog scale for pain score decreased for patients by 3.9 points (95% confidence interval [CI] 2.18-5.60), when compared to preoperative assessment. Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) and Sports subscale scores also improved from 46.5 to 80.9 (95% CI 21.35-47.43), and from 18.8 to 57.9 (95% CI 21.05-57.10), respectively. Short Form-36 Health Survey physical component scores showed significant improvement by an average of 45.5 points (95% CI 32.42-58.50). American Orthopaedic Foot & Ankle Society Ankle-Hindfoot Scale scores improved from 55.2 to 80.3 (95% CI 12.459-37.741).

CONCLUSION

These results demonstrate positive patient-reported long-term outcomes for a cohort of patients with difficult OCLTs, followed over the course of 6-10 years after treatment with arthroscopy-assisted particulated juvenile articular cartilage implantation.

LEVEL OF EVIDENCE

Level II, prospective cohort study.

Sufficient Cartilage for Most Talar Articular Defects Can Be Harvested From the Non-Loadbearing Talus: A Cadaveric Analysis

Purpose

To assess the quantity of morselized cartilage that can be harvested from the non–load-bearing portion of the talus for immediate reimplantation.

Methods

Non–load-bearing talar cartilage was harvested from 5 cadaveric specimens using a standard arthroscopic approach. Cartilage was separated from the talus in maximum dorsiflexion at the junction of the talar head and neck, grasped, and morselized into a graft using a cartilage particulator. The volume of reclaimed cartilage was measured, and the extrapolated area of coverage was compared to average osteochondral lesions of the talus previously reported.

Results

The total yield of cartilage graft following processing that was obtained from 5 ankle joints ranged from 0.3 mL to 2.1 mL with a mean volume of 1.3 ± 0.7 mL, yielding a theoretical 13.2 ± 7.1 cm² coverage with a 1-mm monolayer. While the average size of osteochondral lesions of the talus is difficult to estimate, they may range from 0.5 cm² to 3.7 cm² according to the literature.

Conclusions

This study validated that it is possible to harvest sufficient amount of cartilage for an autologous morselized cartilage graft via a single-stage, single-site surgical and processing technique to address most talar articular cartilage defects.

Clinical Relevance

Particulated cartilage autografts have shown promise in surgical management of cartilage defects. A single-site, single-staged procedure that uses a patient’s autologous talar cartilage from the same joint has the potential to reduce morbidity associated with multiple surgical sites, multistaged procedure, or nonautologous tissue in ankle surgery.

High-Density Autologous Chondrocyte Implantation as Treatment for Ankle Osteochondral Defects

PURPOSE

Two-year follow-up to assess efficacy and safety of high-density autologous chondrocyte implantation (HD-ACI) in patients with cartilage lesions in the ankle.

DESIGN

Twenty-four consecutive patients with International Cartilage repair Society (ICRS) grade 3-4 cartilage lesions of the ankle were included. Five million chondrocytes per cm² of lesion were implanted using a type I/III collagen membrane as a carrier and treatment effectiveness was assessed by evaluating pain with the visual analogue scale (VAS) and American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score at baseline, 12-month, and 24-month follow-up, together with dorsal and plantar flexion. Magnetic resonance observation for cartilage repair tissue (MOCART) score was used to evaluate cartilage healing. Histological study was possible in 5 cases.

RESULTS

Patients' median age was 31 years (range 18-55 years). Median VAS score was 8 (range 5-10) at baseline, 1.5 (range 0-8) at 12-month follow-up, and 2 (rang e0-5) at 24-month follow-up (P < 0.001). Median AOFAS score was 39.5 (range 29-48) at baseline, 90 (range 38-100) at 12-month follow-up, and 90 (range 40-100) at 24-month follow-up (P < 0.001). Complete dorsal flexion significantly increased at 12 months (16/24, 66.7%) and 24 months (17/24, 70.8%) with regard to baseline (13/24, 54.2%) (P = 0.002). MOCART at 12- and 24-month follow-ups were 73.71 ± 15.99 and 72.33 ± 16.21. Histological study confirmed that neosynthetized tissue was cartilage with hyaline extracellular matrix and numerous viable chondrocytes.

CONCLUSION

HD-ACI is a safe and effective technique to treat osteochondral lesions in the talus, providing good clinical and histological results at short- and mid-term follow-ups.

Operative treatments for osteochondral lesions of the talus in adults: A systematic review and meta-analysis

PURPOSE

This systematic review aimed to identify the available evidence regarding the comparative effectiveness and safety of various operative treatments in adult patients with osteochondral lesions of the talus (OLT).

MATERIALS AND METHODS

The PubMed, Embase, ISI Web of Knowledge, and the Cochrane Controlled Trial Register of Controlled Trials were searched from their inception date to September 2019. Two reviewers selected the randomized controlled trials (RCTs) and non-RCTs assessing the comparative effectiveness and safety of various operative treatments for OLT. The meta-analysis was performed using Revman 5.3.

RESULTS

Eight studies (1 RCT and 7 non-RCTs) with 375 patients were included in this review. The difference in the American Orthopaedic Foot and Ankle Society (AOFAS) score between the cartilage repair and replacement was not significant. The cartilage regeneration with or without cartilage repair had significant superiority in improving the AOFAS score compared with the cartilage repair. The difference in the magnetic resonance observation of cartilage repair tissue score between the cartilage repair and replacement and between cartilage repair and cartilage repair plus regeneration was significant.

CONCLUSIONS

Cartilage regeneration and cartilage repair plus regeneration had significant superiority in improving the ankle function and radiological evaluation of OLT, although the trials included did not have high-level evidence. Moreover, which treatment between the 2 was safer could not be addressed in this review as most of the trials did not report the safety outcome. Further studies are needed to define the best surgical option for treating OLT.

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.

Treatment strategies for osteochondral lesions of the talus: A review of the recent evidence

BACKGROUND

There has been no consensus regarding the treatment of osteochondral lesions of the talus, there has been many attempts to formulate a treatment pathway, with multiple proposed modalities and adjuncts used.

OBJECTIVES

The aim of this paper was to investigate the evidence published in the recent history, identify the relevant papers, review and summarize the findings, to help clarify the available operative treatment options and their respective efficacies based on the level of evidence provided.

STUDY DESIGN & METHODS

A literature search through electronic databases MEDLINE and EMBASE was done, these databases were screened for publications and papers form June 2004 to June 2019. Key words were utilised in the search 'talus, talar, tibia, cartilage, osteochondral, ankle, osteochondritis dissecans, articular cartilage'. Studies on adults aged 18-60 years were included. Exclusion criteria were studies with less than 10 patients, or no clear outcome was recorded. Papers were reviewed by the authors and data extracted as per a pre-defined proforma.

RESULTS

Following screening, 28 published articles were included and reviewed. Of these publications 5 were level I, 7 level II, 4 level III and 12 level IV. The total number of patients was 1061 patients. Treatment modalities included arthroscopic microfracture, drilling, hyaluronic acid injection, platelet rich plasma, osteochondral autologous transplantation (OAT), vascularised free bone graft among others. The most common functional measures used to assess efficacy were the Visual analogue scale (VAS) and the American Orthopaedic Foot and Ankle (AOFAS) score. Follow up ranged from 26 weeks upto 4 years.

CONCLUSIONS

Despite the abundance of treatment options, high level evidence (level I) remains limited and does not conclude a definitive treatment modality as superior to others. Further research, in the form highly organised randomised clinical trials, is needed to help improve the efficacy and develop new treatment modalities in the future.

HemiCAP® implantation after failed previous surgery for osteochondral lesions of the talus

BACKGROUND

The aim of this study is to enhance data about the effectiveness of HemiCAP® implantation after failed previous surgery for osteochondral defects (OCDs).

METHODS

12 consecutive patients were retrospectively included in this study. The American Orthopedic Foot and Ankle Society Score (AOFAS), the Visual Analogue Scale (VAS) score for pain, the sub-scales Pain and Disability of the Foot Function Index (FFI-P and FFI-D) Score, and the patients' satisfaction were evaluated.

RESULTS

AOFAS increased from poor to fair (p < 0.001), VAS score decreased from moderate to mild pain (p = 0.001), the final FFI-P and FFI-D were 37.50 ± 18.54 and 33.44 ± 16.24, respectively (p < 0.001). Five patients were not satisfied, three were moderately satisfied and four were highly satisfied. One implant repositioning, one ankle fusion (implant failing) and an additional surgery (double arthrodesis) were performed during the follow-up. Neither intra- nor postoperative complications were registered.

CONCLUSION

Despite the clinical improvement, pain was still present at the final follow-up. Metal resurfacing might not be considered a definitely valid alternative for treatment of OCDs after failed previous surgery.

LEVEL OF EVIDENCE

Level III, retrospective study.

A prospective evaluation of bone marrow aspirate concentrate and microfracture in the treatment of osteochondral lesions of the talus

BACKGROUND

The term osteochondral lesion (OCL) refers to a defect involving the chondral surface and or subchondral bone. These lesions are associated with ankle injuries with bony and soft tissue and cause pain, decreased range of motion, swelling and impact adversely on quality of life. To date the standard treatment has been isolated microfracture (BMS). The aim of this study was to compare the outcomes of BMS alone to BMS augmented with bone marrow aspirate concentrate (BMAC) in the treatment of ankle OCLs.

METHODS

This study was a prospective cohort study carried out from 2010-2015 in a single surgeon's practice. Patients from 2010-2012 were treated with microfracture alone while patients from 2013-2015 were treated with micro fracture augmented with bone marrow aspirate concentrate and fibrin glue. Self-reported patient outcome measures were measured. Complications, revision rates, and visual analogue pain scores were compared.

RESULTS

101 patients were included in the study. 52 patients were in the microfracture group while 49 patients were in the microfracture/BMAC group. The minimum follow-up for both groups was 36 months. Both groups had a statistically significant improvement in pain scores, quality of life scores, participation in sport and activities of daily living. The revision rate was 28.8% in the microfracture group versus 12.2% in the microfracture/BMAC group, which was statistically significant, p=0.0145. The majority of the lesions were less than 1.5cm² in diameter in both cohorts.

CONCLUSIONS

Microfracture and bone marrow aspirate concentrate appears to be a safe and effective treatment option for osteochondral lesions of the talus. The addition of bone marrow aspirate concentrate does not result in any increase in ankle or donor site morbidity. It is a well-tolerated therapy which decreases revision rates for treatment of the osteochondral lesions when compared to microfracture alone.

LEVEL OF EVIDENCE

Level III.

Large Osteochondral Lesions of the Talus Treated With Autologous Bone Graft and Periosteum Transfer

Background:

The treatment of large osteochondral lesions of the talus (OLTs) is challenging due to the poor intrinsic reparative capability of the damaged articular cartilage. Autologous transfer of bone and periosteum has been used successfully in the treatment of large defects in animals, and therefore it was believed that this technique might show similar results in humans. The purpose of this study was to assess the outcome of an innovative technique for autologous transplantation of cancellous tibial graft with periosteal transfer in large OLTs.

Methods:

Forty-one patients (22 females, 19 males), with a mean age of 34.9 years (range, 18-72 years), with a large OLT (>200 mm²) were treated with autologous bone graft and periosteum transfer. OLTs averaging 310 mm² were identified on a preoperative computed tomography scan. The procedure consisted of malleolar osteotomy, curettage of sclerotic bone, autologous bone graft from the proximal tibia, and transfixion of periosteum over the graft. Outcome measures, including the pain visual analog scale (VAS), ankle range of motion (ROM), American Orthopaedic Foot & Ankle Society (AOFAS) score, and Foot & Ankle Disability Index (FADI), were compared between preoperative and 1 and 2 years following surgery.

Results:

There were significant improvements in VAS pain score from 7.7 before surgery to 1.1 at 1 year after surgery and 0.4 at 2 years or more after surgery. The AOFAS and FADI scores were also significantly improved from 40.3 and 53.3 preoperatively to 95 and 93.2 postoperatively at 1 year and 95 and 93.2 at 2 or more years postoperatively, respectively. Postoperative complications included 2 patients who required removal of medial malleolar osteotomy tension bands due to symptomatic hardware. There were no nonunions or malunions of the osteotomies and no donor site complications.

Conclusion:

Autologous bone graft and periosteum transfer was an effective treatment for large OLTs leading to significant decreases in pain and improvement in functional scores at more than 2 years after surgery.

Level of Evidence:

Level IV, retrospective case series.

Matrix-associated stem cell transplantation (MAST) in chondral lesions at the ankle as part of a complex surgical approach- 5-year-follow-up in 100 patients

BACKGROUND

The aim of the study was to assess the 5-year-follow-up after matrix-associated stem cell transplantation (MAST) in chondral lesions at the ankle as part of a complex surgical approach.

METHODS

In a prospective consecutive non-controlled clinical follow-up study, all patients with chondral lesion at the ankle that were treated with MAST from April 1, 2009 to May 31, 2012 were included. Size and location of the chondral lesions, method-associated problems and the Visual-Analogue-Scale Foot and Ankle (VAS FA) before treatment and at follow-up were analysed. Stem cell-rich blood was harvested from the ipsilateral pelvic bone marrow and centrifuged (10min, 1500RPM). The supernatant was used to impregnate a collagen I/III matrix (Chondro-Gide) that was fixed into the chondral lesion with fibrin glue.

RESULTS

One hundred and twenty patients with 124 chondral lesions were included in the study. Age at the time of surgery was 35 years on average (range, 12-65 years), 74 (62%) were male. VAS FA before surgery was 45.2 on average (range, 16.4-73.5). Lesions were located at medial talar shoulder, n=55; lateral talar shoulder, n=58 (medial and lateral, n=4); tibia, n=11. Lesion size was 1.7cm² on average (range, .8-6cm²). One hundred patients (83%) completed 5-year-follow-up after. VAS FA improved to 84.4 (range, 54.1-100; t-test, p<0.01).

CONCLUSIONS

MAST as part of a complex surgical approach led to improved and high validated outcome scores in the mid-term-follow-up. No method related complications were registered. Even though a control group is missing, we conclude that MAST as part of a complex surgical approach is an effective method for the treatment of chondral lesions of the ankle for at least five years.

Particulated Autograft Cartilage Implantation for the Treatment of Osteochondral Lesions of the Talus: A Novel Technique

Osteochondral lesions of the talus often occur following ankle sprains and fractures. Operative intervention is typically required because of the diminished intrinsic repair capability of talar articular cartilage. Several techniques have evolved that emphasize replacing the defect with cartilage that closely mimics the biological properties of hyaline articular cartilage. The goals of operative treatment are resolution of symptoms, physiologic healing, and restoration of function while eliminating the need for further intervention. This article describes a novel, single-step technique for the treatment of osteochondral lesions of the talus with the use of particulated autograft cartilage implantation.

LEVELS OF EVIDENCE

Level V.

Osteochondral Lesions of the Talus

Osteochondral lesions of the talus (OLTs) are a difficult pathologic entity to treat. They require a strong plan. Lesion size, location, chronicity, and characteristics such as displacement and the presence of subchondral cysts help dictate the appropriate treatment required to achieve a satisfactory result. In general, operative treatment is reserved for patients with displaced OLTs or for patients who have failed nonoperative treatment for 3 to 6 months. Operative treatments can be broken down into cartilage repair, replacement, and regenerative strategies. There are many promising treatment options, and research is needed to elucidate which are superior to minimize the morbidity from OLTs.

Scaffold-Based Therapies: Proceedings of the International Consensus Meeting on Cartilage Repair of the Ankle

BACKGROUND

The evidence supporting best practice guidelines in the field of cartilage repair of the ankle are based on both low quality and low levels of evidence. Therefore, an international consensus group of experts was convened to collaboratively advance toward consensus opinions based on the best available evidence on key topics within cartilage repair of the ankle. The purpose of this article is to report the consensus statements on "Scaffold-Based Therapies" developed at the 2017 International Consensus Meeting on Cartilage Repair of the Ankle.

METHODS

Seventy-five international experts in cartilage repair of the ankle representing 25 countries and 1 territory were convened and participated in a process based on the Delphi method of achieving consensus. Questions and statements were drafted within 11 working groups focusing on specific topics within cartilage repair of the ankle, after which a comprehensive literature review was performed and the available evidence for each statement was graded. Discussion and debate occurred in cases where statements were not agreed upon in unanimous fashion within the working groups. A final vote was then held, and the strength of consensus was characterized as follows: consensus, 51% to 74%; strong consensus, 75% to 99%; unanimous, 100%.

RESULTS

A total of 9 statements on scaffold-based therapies reached consensus during the 2017 International Consensus Meeting on Cartilage Repair of the Ankle. One achieved unanimous support, 8 reached strong consensus (greater than 75% agreement), and 1 was removed because of redundancy in the information provided. All statements reached at least 80% agreement.

CONCLUSIONS

This international consensus derived from leaders in the field will assist clinicians with applying scaffold-based therapies as a treatment strategy for osteochondral lesions of the talus.

LEVEL OF EVIDENCE

Level V, expert opinion.

Revision and Salvage Management: Proceedings of the International Consensus Meeting on Cartilage Repair of the Ankle

BACKGROUND

The evidence supporting best practice guidelines in the field of cartilage repair of the ankle are based on both low quality and low levels of evidence. Therefore, an international consensus group of experts was convened to collaboratively advance toward consensus opinions based on the best available evidence on key topics within cartilage repair of the ankle. The purpose of this article was to report on the consensus statements on "Revision and Salvage Management" developed at the 2017 International Consensus Meeting on Cartilage Repair of the Ankle.

METHODS

Seventy-five international experts in cartilage repair of the ankle representing 25 countries and 1 territory were convened and participated in a process based on the Delphi method of achieving consensus. Questions and statements were drafted within 11 working groups focusing on specific topics within cartilage repair of the ankle, after which a comprehensive literature review was performed and the available evidence for each statement was graded. Discussion and debate occurred in cases where statements were not agreed on in unanimous fashion within the working groups. A final vote was then held, and the strength of consensus was characterized as follows: consensus, 51% to 74%; strong consensus, 75% to 99%; unanimous, 100%.

RESULTS

A total of 8 statements on revision and salvage management reached consensus during the 2017 International Consensus Meeting on Cartilage Repair of the Ankle. One achieved unanimous support and 7 reached strong consensus (greater than 75% agreement). All statements reached at least 85% agreement.

CONCLUSIONS

This international consensus derived from leaders in the field will assist clinicians with revision and salvage management in the cartilage repair of the ankle.

Surgical management of large talar osteochondral defects using autologous chondrocyte implantation

BACKGROUND

Talar osteochondral lesions (OLT) occur frequently in ankle sprains and fractures. We hypothesize that matrix-induced autologous chondrocyte implantation (MACI) will have a low reoperation rate and high patient satisfaction rate in treating OLT less than 2.5cm².

METHODS

A systematic review was registered with PROSPERO and performed with PRISMA guidelines using three publicly available free databases. Clinical outcome investigations reporting OLT outcomes with levels of evidence I-IV were eligible for inclusion. All study, subject, and surgical technique demographics were analyzed and compared. Statistics were calculated using Student's t-tests, one-way ANOVA, chi-squared, and two-proportion Z-tests.

RESULTS

Nineteen articles met our inclusion criteria, which resulted in a total of 343 patients. Six studies pertained to arthroscopic MACI, 8 to open MACI, and 5 studies to open periosteal ACI (PACI). All studies were Level IV evidence. Due to study quality, imprecise and sparse data, and potential for reporting bias, the quality of evidence is low. In comparison of open and arthroscopic MACI, we found both advantages favoring open MACI. However, open MACI had higher complication rates.

CONCLUSIONS

No procedure demonstrates superiority or inferiority between the combination of open or arthroscopic MACI and PACI in the management of OLT less than 2.5cm². Ultimately, well-designed randomized trials are needed to address the limitation of the available literature and further our understanding of the optimal treatment options.

Osteochondral lesions of the ankle: The current evidence supporting scaffold-based techniques and biological adjuncts

BACKGROUND

Talar osteochondral lesions are more common than has been previously recognized. Optimal treatment remains unclear and the subject of much debate in the literature. Although reparative techniques such as microfracture have produced initial good results and remain the gold standard in the management of these lesions, the literature is deficient in long-term data. Recently, techniques focused on enhancing the local biological environment have been developed which have demonstrated promising outcomes.

METHODS

We reviewed the available evidence concerning scaffold-based techniques and biological adjuncts in the management of talar osteochondral lesions published in the English language on PubMed.

RESULTS

An update is provided on the current evidence concerning the role of biological adjuncts in the management of osteochondral lesions of the talus.

CONCLUSIONS

There has been an explosion of interest among the orthopaedic community in the role of biologics in the management of complex talar osteochondral lesions. A number of exciting new techniques have been developed which show promise. Robust randomized control trials are required to identify the optimal surgical strategy.

Use of mesenchymal stem cells seeded on the scaffold in articular cartilage repair

Articular cartilage has poor capacity for repair. Once damaged, they degenerate, causing functional impairment of joints. Allogeneic cartilage transplantation has been performed for functional recovery of articular cartilage. However, there is only a limited amount of articular cartilage available for transplantation. Mesenchymal stem cells (MSCs) could be potentially suitable for local implantation. MSCs can differentiate into chondrocytes. Several studies have demonstrated the therapeutic potential of MSCs in the repair of articular cartilage in animal models of articular cartilage damage and in patients with damaged articular cartilage. To boost post-implantation MSC differentiation into chondrocytes, the alternative delivery methods by scaffolds, using hyaluronic acid (HA) or poly-lactic-co-glycolic-acid (PLGA), have developed. In this review, we report recent data on the repair of articular cartilage and discuss future developments.

Efficacy of Particulated Juvenile Cartilage Allograft Transplantation for Osteochondral Lesions of the Talus

BACKGROUND

Particulated juvenile cartilage allograft transplantation (PJCAT) is a novel treatment option for osteochondral lesions of the talus (OLTs). It is typically employed as a salvage procedure after initial debridement and microfracture has failed as it is theorized to deliver viable hyaline cartilage. We hypothesized that PJCAT would be a safe and effective treatment option for OLTs.

METHODS

This is a retrospective case-control study of patients who underwent PJCAT for the treatment of OLTs at a single academic institution. Failure of the procedure was defined as no change or worsening of symptoms and/or the need for a subsequent cartilage restoration procedure. Variables recorded included preoperative magnetic resonance imaging (MRI) area and volume, intraoperative size, etiology, lesion location, sex, age, body mass index (BMI), history of prior surgery, American Orthopaedic Foot & Ankle Society score, and foot and ankle outcome score. Fifteen patients completed a minimum of 12 months of follow-up (mean, 34.6 months).

RESULTS

The failure rate of PJCAT in this series was 40% (6/15). Preoperative MRI area and intraoperative OLT size along with male sex were predictive of failure ( P < .05). Age, BMI, etiology, technique (open vs arthroscopic), history of prior surgery, and location of lesion were not predictors of failure in this limited series ( P > .05). Patients with lesions greater than 125 mm² area had a significant increased risk of clinical failure ( P < .05). Functional outcome scores were significantly better at final follow-up in the patients who had undergone successful treatment vs those who did not.

CONCLUSION

These findings demonstrate the association of preoperative MRI lesion area, intraoperative lesion size, and male sex as risk factors for failure of PJCAT setting of an already difficult to treat pathology.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Correlation of MRI Appearance of Autologous Chondrocyte Implantation in the Ankle with Clinical Outcome

The objective of this study was to characterize magnetic resonance imaging (MRI) findings and correlate with clinical results in patients who underwent autologous chondrocyte implantation (ACI) of osteochondral lesions of the talus (OLT).

METHODS

Twenty-four grafts were evaluated at a mean 65.8 months after ACI for OLT. MRI was performed on a 1.5-T GE scanner using multiple sequences. Graft appearance was compared with preoperative MRI and evaluated for 6 criteria: defect fill, surface regularity, signal pattern, bone marrow edema, subchondral plate irregularity, and presence of cystic lesions. Clinical outcome was measured with the American Orthopaedic Foot and Ankle Society (AOFAS) clinical outcome score.

RESULTS

Of 24 grafts, 22 (92%) demonstrated >75% defect fill. Eighteen (75%) had a mildly irregular and 6 (25%) had a moderately irregular articular surface. The signal pattern of the repair tissue was heterogenous in 23 (96%); 14 (58%) layered and 9 (38%) mottled. Fourteen grafts (58%) showed decreased amount of bone marrow edema while 4 (17%) had no change and 5 (21%) had an increase in the amount of bone marrow edema. The subchondral bone plate was abnormal in most grafts, with focal defects seen in 10, slight depression in 7, and both in 5. Seven had an increase in cystic lesions while the others had no change, decrease or no cysts seen. Mean postoperative AOFAS score was 87.5 with mean improvement of 39.4.

CONCLUSIONS

At 66-month mean follow-up, MRI appearance of the ACI grafts show imaging abnormalities but demonstrate good clinical results. While MRI is an important tool in the postoperative assessment of ACI grafts, the various variations from a normal/nonoperative ankle must be interpreted with caution.

Matrix-associated stem cell transplantation (MAST) in chondral defects of the ankle is safe and effective - 2-year-followup in 130 patients

BACKGROUND

The aim of the study was to assess the 2-year-follow-up of matrix-associated stem cell transplantation (MAST) in chondral defects of the ankle.

METHODS

In a prospective consecutive non-controlled clinical follow-up study, all patients with chondral defect that were treated with MAST from October 1, 2011 to July 31, 2013 were analyzed. Size and location of the chondral defects, method-associated problems and the Visual Analogue Scale Foot and Ankle (VAS FA) before treatment and at follow-up were analyzed. Stem cell-rich blood was harvested from the ipsilateral pelvic bone marrow and centrifuged (10min, 1500rpm). The supernatant was used to impregnate a collagen I/III matrix (Chondro-Gide). The matrix was fixed into the chondral defect with fibrin glue.

RESULTS

One hundred and forty-four patients with 150 chondral defects were included in the study. The age of the patients was 35 years on average (range, 12-68 years), 85 (59%) were male. The VAS FA before surgery was 48.5 on average (range, 16.5-78.8). The defects were located as follows, medial talar shoulder, n=62; lateral talar shoulder, n=66 (medial and lateral talar shoulder, n=6), tibia, n=22. The defect size was 1.6cm² on average (range, .6-6cm²). 130 patients (90%) completed 2-year-follow-up. The VAS FA improved to an average of 87.5 (range, 62.1-100; t-test (comparison with preoperative scores), p=.01).

CONCLUSIONS

MAST led to improved and high validated outcome scores. No method related complications were registered. Even though a control group is missing, we conclude that MAST is a safe and effective method for the treatment of chondral defects of the ankle.

Topical Review: MACI as an Emerging Technology for the Treatment of Talar Osteochondral Lesions

Matrix-induced autologous chondrocyte implantation (MACI) is a viable procedure that can be used as both a primary or revision cartilage regenerative procedure in high-functioning individuals without tibiotalar arthritis. Both short-term and midterm follow-up results demonstrate clinical, radiographic, and functional improvements with high rates of return to full activities. Cost remains a chief concern with the use of this technique, but theoretical improvements in the durability of repair with type II cartilage replacement may offer long-term benefits.

LEVEL OF EVIDENCE

Level V, expert opinion.

Restorative Tissue Transplantation Options for Osteochondral Lesions of the Talus: A Review

Symptomatic osteochondral lesions of the talus remain a challenging problem due to inability for cartilage lesions to heal. Numerous treatment options exist, including nonoperative management, marrow stimulating techniques, and autograft-allograft. Arthroscopic marrow stimulation forms fibrocartilage that has been shown to be biomechanically weaker than hyaline cartilage. Restorative tissue transplantation options are being used more for larger and cystic lesions. Newer biologics and particulated juvenile cartilage are currently under investigation for possible clinical efficacy. This article provides an evidenced-based summary of available literature on the use of biologics for treatment of osteochondral lesions of the talus.

Osteochondral lesions of the talus in the athlete: up to date review

PURPOSE OF REVIEW

Osteochondral lesions of the talus (OLT) are common injuries in athletes. The purpose of this study is to comprehensively review the clinical results and return to sport capacity in athletes following treatment for OLT.

RECENT FINDINGS

Reparative procedures, such as bone marrow stimulation, and replacement procedures, such as autologous osteochondral transplantation, provide good clinical outcomes in short- and mid-term follow-up in the athlete. Recently, biological augmentation and scaffold-based therapies have been shown to improve clinical and radiological outcomes in OLT in both the general population and athletes. Most studies are of a low level of evidence. Studies analyzing the return to sport capability in athletes are further lacking. High-level evidence and well-designed clinical trials are required to establish the most effective treatment protocol.

Evaluation and Management of Osteochondral Lesions of the Talus

Osteochondral lesions of the talus are common injuries that affect a wide variety of active patients. The majority of these lesions are associated with ankle sprains and fractures though several nontraumatic etiologies have also been recognized. Patients normally present with a history of prior ankle injury and/or instability. In addition to standard ankle radiographs, magnetic resonance imaging and computed tomography are used to characterize the extent of the lesion and involvement of the subchondral bone. Symptomatic nondisplaced lesions can often be treated conservatively within the pediatric population though this treatment is less successful in adults. Bone marrow stimulation techniques such as microfracture have yielded favorable results for the treatment of small (<15 mm) lesions. Osteochondral autograft can be harvested most commonly from the ipsilateral knee and carries the benefit of repairing defects with native hyaline cartilage. Osteochondral allograft transplant is reserved for large cystic lesions that lack subchondral bone integrity. Cell-based repair techniques such as autologous chondrocyte implantation and matrix-associated chondrocyte implantation have been increasingly used in an attempt to repair the lesion with hyaline cartilage though these techniques require adequate subchondral bone. Biological agents such as platelet-rich plasma and bone marrow aspirate have been more recently studied as an adjunct to operative treatment but their use remains theoretical. The present article reviews the current concepts in the evaluation and management of osteochondral lesions of the talus, with a focus on the available surgical treatment options.

Repair Potential of Matrix-Induced Bone Marrow Aspirate Concentrate and Matrix-Induced Autologous Chondrocyte Implantation for Talar Osteochondral Repair: Patterns of Some Catabolic, Inflammatory, and Pain Mediators

OBJECTIVE

The low regenerative potential of cartilage contributed to the development of different cell therapies aimed to improve the clinical outcome in young patients with Osteochondral Lesions of the Talus (OLT). This study is designed to assess the regenerative potential of autologous matrix-induced Bone Marrow Aspirate Concentrate (mBMAC) and matrix-induced Autologous Chondrocyte Implantation (mACI) evaluating, on a small number of osteochondral biopsies, the expression of some catabolic, inflammatory, and pain mediators.

DESIGN

Twenty-two patients with OLT were analyzed in this study; 7 were treated with mACI and 15 with mBMAC. Informed consent was obtained from all the patients. Clinical assessments were performed pre-operatively and at 12, 24, and 36 months after surgery using the American Orthopedic Foot and Ankle Society (AOFAS). Histology and immunohistochemistry were used to assess cartilage repair at 24 months. Data were analyzed using non-parametric Wilcoxon-Mann-Whitney and Spearman tests.

RESULTS

A remarkable improvement in AOFAS score was noticed for both treatments up to 36 months; however, patients treated with mACI reported the best AOFAS score. Various degrees of tissue remodeling were observed by histological analysis for both cell strategies. However, mBMAC treatment showed a higher expression of some fibrous and hypertrophic markers compared to mACI group. A mild positivity for nerve growth factor, as pain mediator, was noticed for both treatments.M.

CONCLUSIONS

Our findings demonstrated the best histological and clinical results following mACI treatment since different fibrotic and hypertrophic features were evident in the mBMAC group at 24-month follow-up.

Evaluating Joint Morbidity after Chondral Harvest for Autologous Chondrocyte Implantation (ACI): A Study of ACI-Treated Ankles and Hips with a Knee Chondral Harvest

OBJECTIVE

To establish if harvesting cartilage to source chondrocytes for autologous chondrocyte implantation (ACI) results in donor site morbidity.

DESIGN

Twenty-three patients underwent ACI for chondral defects of either the ankle or the hip. This involved cartilage harvest from the knee (stage I), chondrocyte expansion in the laboratory and implantation surgery (stage II) into the affected joint. Prior to chondral harvest, no patient had sought treatment for their knee. Lysholm knee scores were completed prior to chondral harvest and annually post-ACI. Histological analyses of the donor site were performed at 12.3 ± 1.5 months for 3 additional patients who had previously had ACI of the knee.

RESULTS

The median preoperative Lysholm score was 100, with no significant differences observed at either 13.7±1.7 months or 4.8±1.8 years postharvest (median Lysholm scores 91.7 and 87.5, respectively). Patients whose cartilage was harvested from the central or medial trochlea had a significantly higher median Lysholm score at latest follow-up (97.9 and 93.4, respectively), compared with those taken from the intercondylar notch (median Lysholm score 66.7). The mean International Cartilage Repair Society (ICRS) II histological score for the biopsies taken from the donor site of 3 additional knee ACI patients was 117 ± 10 (maximum score 140).

CONCLUSIONS

This study suggests that the chondral harvest site in ACI is not associated with significant joint morbidity, at least up to 5 years postharvest. However, one should carefully consider the location for chondral harvest as this has been shown to affect knee function in the longer term.

Low Level of Evidence and Methodologic Quality of Clinical Outcome Studies on Cartilage Repair of the Ankle

PURPOSE

To examine the level of evidence and methodologic quality of studies reporting surgical treatments for osteochondral lesions of the ankle.

METHODS

A search was performed using the PubMed/Medline, Embase, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and Cochrane databases for all studies in which the primary objective was to report the outcome after surgical treatment of osteochondral lesions of the ankle. Studies reporting outcomes of microfracture, bone marrow stimulation, autologous osteochondral transplantation, osteochondral allograft transplantation, and autologous chondrocyte implantation were the focus of this analysis because they are most commonly reported in the literature. Two independent investigators scored each study from 0 to 100 based on 10 criteria from the modified Coleman Methodology Score (CMS) and assigned a level of evidence using the criteria established by the Journal of Bone and Joint Surgery. Data were collected on the study type, year of publication, number of surgical procedures, mean follow-up, preoperative and postoperative American Orthopaedic Foot & Ankle Society score, measures used to assess outcome, geography, institution type, and conflict of interest.

RESULTS

Eighty-three studies reporting the results of 2,382 patients who underwent 2,425 surgical procedures for osteochondral lesions of the ankle met the inclusion criteria. Ninety percent of studies were of Level IV evidence. The mean CMS for all scored studies was 53.6 of 100, and 5 areas were identified as methodologically weak: study size, type of study, description of postoperative rehabilitation, procedure for assessing outcome, and description of the selection process. There was no significant difference between the CMS and the type of surgical technique (P = .1411). A statistically significant patient-weighted correlation was found between the CMS and the level of evidence (r = -0.28, P = .0072). There was no statistically significant patient-weighted correlation found between the CMS and the institution type (r = 0.05, P = .6480) or financial conflict of interest (r = -0.16, P = .1256).

CONCLUSIONS

Most studies assessing the clinical outcomes of cartilage repair of the ankle are of a low level of evidence and of poor methodologic quality.

LEVEL OF EVIDENCE

Level IV, systematic review of Level I through IV studies.

Therapeutic Potential of Differentiated Mesenchymal Stem Cells for Treatment of Osteoarthritis

Osteoarthritis (OA) is a chronic, progressive, and irreversible degenerative joint disease. Conventional OA treatments often result in complications such as pain and limited activity. However, transplantation of mesenchymal stem cells (MSCs) has several beneficial effects such as paracrine effects, anti-inflammatory activity, and immunomodulatory capacity. In addition, MSCs can be differentiated into several cell types, including chondrocytes, osteocytes, endothelia, and adipocytes. Thus, transplantation of MSCs is a suggested therapeutic tool for treatment of OA. However, transplanted naïve MSCs can cause problems such as heterogeneous populations including differentiated MSCs and undifferentiated cells. To overcome this problem, new strategies for inducing differentiation of MSCs are needed. One possibility is the application of microRNA (miRNA) and small molecules, which regulate multiple molecular pathways and cellular processes such as differentiation. Here, we provide insight into possible strategies for cartilage regeneration by transplantation of differentiated MSCs to treat OA patients.

Regenerative treatment in osteochondral lesions of the talus: autologous chondrocyte implantation versus one-step bone marrow derived cells transplantation

PURPOSE

Osteochondral lesions of the talus (OLT) usually require surgical treatment. Regenerative techniques for hyaline cartilage restoration, like autologous chondrocytes implantation (ACI) or bone marrow derived cells transplantation (BMDCT), should be preferred. The aim of this work is comparing two clusters with OLT, treated with ACI or BMDCT.

METHODS

Eighty patients were treated with regenerative techniques, 40 with ACI and 40 with BMDCT. The two groups were homogenous regarding age, lesion size and depth, previous surgeries, etiology of the lesion, subchondral bone graft, final follow-up and pre-operative AOFAS score. The two procedures were performed arthroscopically. The scaffold was a hyaluronic acid membrane in all the cases, loaded with previously cultured chondrocytes (ACI) or with bone marrow concentrated cells, harvested in the same surgical session (BMDCT). All the patients were clinically and radiologically evaluated, using MRI Mocart score and T2 mapping sequence.

RESULTS

Clinical results were similar in both groups at 48 months. No statistically significant influence was reported after evaluation of all the pre-operative parameters. The rate of return to sport activity showed slightly better results for BMDCT than ACI. MRI Mocart score was similar in both groups. MRI T2 mapping evaluation highlighted a higher presence of hyaline like values in the BMDCT group, and lower incidence of fibrocartilage as well.

CONCLUSIONS

To date, ACI and BMDCT showed to be effective regenerative techniques for the treatment of OLT. BMDCT could be preferred over ACI for the single step procedure, patients' discomfort and lower costs.

Autologous chondrocyte implantation of the ankle: 2- to 10-year results

BACKGROUND

The treatment of osteochondral lesions of the talus after failed surgery is challenging, with no clear solution. Short-term results using autologous chondrocyte implantation have been promising.

PURPOSE

To report the long-term outcomes of patients who underwent autologous chondrocyte implantation (ACI) of the talus after failed marrow stimulation techniques for osteochondral lesions of the talus (OLTs).

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Thirty-two consecutive patients underwent ACI of the talus, and 29 patients (15 male, 14 female; mean age, 34 years [range, 16-54 years]) were available for follow-up. There were 23 medial and 6 lateral lesions, with a mean size of 18 × 11 mm (198 mm(2); range, 80-500 mm(2)). Twenty patients underwent ACI of the talus alone; 9 underwent ACI with bone grafting of underlying cysts. Follow-up was performed at a mean of 70 months (range, 24-129 months). Patient outcomes were evaluated using the simplified symptomatology score, Tegner activity score, Finsen score, and American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score. Twenty-five patients (86%) underwent second-look arthroscopic surgery at the time of hardware removal and were assessed with the International Cartilage Repair Society (ICRS) score. Postoperative magnetic resonance imaging (MRI) was performed on 24 patients (83%) and compared with preoperative MRI scans.

RESULTS

Preoperatively, 26 patients rated their ankles as poor and 3 as fair using the simplified symptomatology score. At last follow-up, 9 were classified as excellent, 14 as good, 5 as fair, and 1 as poor using the same score. The mean AOFAS score improved from 50.1 to 85.9 (range, 65-100). The mean Tegner activity score improved from 1.6 to 4.3 (P < .0001). The mean Finsen score (modified Weber score) showed significant improvement from 13.7 to 5.1 (P < .0001).

CONCLUSION

Autologous chondrocyte implantation of the talus yields improvement in all parameters tested with enduring long-term results in patients who have failed previous surgery for OLTs.

Arthroscopic autologous chondrocyte implantation in the ankle joint

PURPOSE

Autologous chondrocyte implantation (ACI) is an established procedure in the ankle providing satisfactory results. The development of a completely arthroscopic ACI procedure in the ankle joint made the technique easier and reduced the morbidity. The purpose of this investigation was to report the clinical results of a series of patients who underwent arthroscopic ACI of the talus at a mean of 7 ± 1.2-year follow-up.

METHODS

Forty-six patients (mean age 31.4 ± 7.6) affected by osteochondral lesions of the talar dome (OLT) received arthroscopic ACI between 2001 and 2006. Patients were clinically evaluated using AOFAS score pre-operatively and at 12, 36 months and at final follow-up of 87.2 ± 14.5 months.

RESULTS

The mean pre-operative AOFAS score was 57.2 ± 14.3. At the 12-month follow-up, the mean AOFAS score was 86.8 ± 13.4 (p = 0.0005); at 36 months after surgery, the mean score was 89.5 ± 13.4 (p = 0.0005); whereas at final follow-up of 87.2 ± 14.5 months it was 92.0 ± 11.2 (p = 0.0005). There were three failures. Histological and immunohistochemical evaluations of specimens harvested from failed implants generally showed several aspects of a fibro-cartilaginous tissue associated with some aspects of cartilage tissue remodelling as indicated by the presence of type II collagen expression.

CONCLUSION

This study confirmed the ability of arthroscopic ACI to repair osteochondral lesions in the ankle joint with satisfactory clinical results after mid-term follow-up.

LEVEL OF EVIDENCE

IV, retrospective case series.

Osteochondral lesions of the talus: aspects of current management

Osteochondral lesions (OCLs) occur in up to 70% of sprains and fractures involving the ankle. Atraumatic aetiologies have also been described. Techniques such as microfracture, and replacement strategies such as autologous osteochondral transplantation, or autologous chondrocyte implantation are the major forms of surgical treatment. Current literature suggests that microfracture is indicated for lesions up to 15 mm in diameter, with replacement strategies indicated for larger or cystic lesions. Short- and medium-term results have been reported, where concerns over potential deterioration of fibrocartilage leads to a need for long-term evaluation. Biological augmentation may also be used in the treatment of OCLs, as they potentially enhance the biological environment for a natural healing response. Further research is required to establish the critical size of defect, beyond which replacement strategies should be used, as well as the most appropriate use of biological augmentation. This paper reviews the current evidence for surgical management and use of biological adjuncts for treatment of osteochondral lesions of the talus.

Mesenchymal stem cells in the treatment of traumatic articular cartilage defects: a comprehensive review

Articular cartilage has a limited capacity to repair following injury. Early intervention is required to prevent progression of focal traumatic chondral and osteochondral defects to advanced cartilage degeneration and osteoarthritis. Novel cell-based tissue engineering techniques have been proposed with the goal of resurfacing defects with bioengineered tissue that recapitulates the properties of hyaline cartilage and integrates into native tissue. Transplantation of mesenchymal stem cells (MSCs) is a promising strategy given the high proliferative capacity of MSCs and their potential to differentiate into cartilage-producing cells - chondrocytes. MSCs are historically harvested through bone marrow aspiration, which does not require invasive surgical intervention or cartilage extraction from other sites as required by other cell-based strategies. Biomaterial matrices are commonly used in conjunction with MSCs to aid cell delivery and support chondrogenic differentiation, functional extracellular matrix formation and three-dimensional tissue development. A number of specific transplantation protocols have successfully resurfaced articular cartilage in animals and humans to date. In the clinical literature, MSC-seeded scaffolds have filled a majority of defects with integrated hyaline-like cartilage repair tissue based on arthroscopic, histologic and imaging assessment. Positive functional outcomes have been reported at 12 to 48 months post-implantation, but future work is required to assess long-term outcomes with respect to other treatment modalities. Despite relatively positive outcomes, further investigation is required to establish a consensus on techniques for treatment of chondral and osteochondral defects with respect to cell source, isolation and expansion, implantation density, in vitro precultivation, and scaffold composition. This will allow for further optimization of MSC proliferation, chondrogenic differentiation, bioengineered cartilage integration, and clinical outcome.