Cost-effectiveness analysis of autologous chondrocyte implantation: a comparison of periosteal patch versus type I/III collagen membrane

Do reconstructive techniques for osteochondritis dissecans of the skeletally mature knee work? A systematic review and meta-analysis

PURPOSE

Osteochondritis dissecans (OCD) is a common cause of knee pain. Management for adult-onset OCD (AOCD) usually involves surgery. Surgical treatments include palliative, reparative and reconstructive techniques. The aim of this systematic review and meta-analysis is to evaluate the efficacy of reconstructive techniques for the treatment of OCD in skeletally mature knees.

METHODS

A systematic search was carried out on four databases up to November 2023 (Medline, Embase, Cochrane Library, Web of Science). The study was registered on international prospective register of systematic reviews and performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Clinical studies on skeletally mature patients were included, which utilised reconstructive techniques such as autologous chondrocyte implantation (ACI), matrix-induced autologous chondrocyte implantation, osteochondral allograft transplantation surgery or bone marrow-derived cellular transplantation. Demographical data, patient-reported outcome measures and postoperative complications were recorded. Quantitative outcome measures that were comparable across studies were pooled for meta-analysis. A random effects model was used. Heterogeneity was assessed using the I2 statistic and Cochran's Q test. Statistical significance was set at p < 0.05. Risk of bias was assessed using the risk of bias in non-randomised studies - of interventions tool for nonrandomised studies.

RESULTS

Sixteen studies were included with 458 OCD lesions in 432 patients. The average age was 24.9, and 62.6% were male. The mean follow-up time was 61.5 months. At 36 months follow-up, International Knee Documentation Committee (IKDC) subjective, Tegner and EuroQol-visual analogue scale (EQ-VAS) scores improved from 42.4 to 78.6 (standard mean difference [SMD]: 2.47; p < 0.001), 2.27-4.99 (SMD: 2.363; p = 0.002) and 30.4-57.5 (SMD: 2.390; p < 0.001), respectively. Overall complication rate was 8.9%. Smaller OCD lesion sizes resulted in a greater improvement in IKDC subjective (SMD: 2.64 vs. 2.01; p = 0.038), EQ-VAS (SMD: 3.16 vs. 0.95; p = 0.046) and Tegner scores (SMD: 3.13 vs. 1.05; p = 0.007) and had a lower complication rate (p = 0.008). Males showed a larger improvement in IKDC subjective scores than females (SMD: 2.56 vs. 1.56; p = 0.029), while younger patients had a larger improvement in IKDC subjective scores (SMD: 2.71 vs. 2.12; p = 0.045) and fewer complications than older patients (p = 0.003). There were no significant differences between cohorts treated with ACI and those treated with non-ACI reconstructive techniques. Publication bias was not detected (n.s.).

CONCLUSION

Reconstructive techniques used to treat OCD in the skeletally mature knee resulted in significant improvements in clinical and functional outcomes, with a low overall complication rate. Since a younger age leads to a greater improvement in IKDC subjective score and a lower complication rate, surgical intervention should not be delayed, especially in AOCD lesions which are more likely to follow a progressive and unremitting clinical course.

LEVEL OF EVIDENCE

Level III.

Comparative study on clinical outcomes in autologous chondrocyte implantation using three-dimensional cultured JACC® with collagen versus periosteum coverings

This study investigates the efficacy of a collagen membrane as a substitute for autologous periosteum in atelocollagen-assisted autologous chondrocyte implantation (ACI) using J-TEC autologous cultured cartilage (JACC®). Sixty-nine patients with knee joint chondral defects underwent ACI using JACC®-34 with periosteum-covered ACI (P-ACIs) and 35 with collagen-covered ACI (C-ACIs). Clinical outcomes were compared through patient-reported measures, International Cartilage Repair Society (ICRS) Cartilage Repair Assessment (CRA) scores at second-look arthroscopy one year postoperatively, and adverse event incidence. Postoperative subjective scores significantly improved up to two years, with no significant differences between P-ACI and C-ACI groups. However, C-ACI exhibited a lower adverse event rate (p = 0.034) and significantly higher ICRS CRA scores (p = 0.0001). Notably, C-ACI outperformed P-ACI in both femoral condyle and trochlea assessments (p = 0.0157 and 0.0005, respectively). While clinical outcomes were comparable, the use of a collagen membrane demonstrated superiority in ICRS CRA during second-look arthroscopy and adverse event occurrence.

Challenges for Economic Evaluations of Advanced Therapy Medicinal Products: A Systematic Review

OBJECTIVES

Advanced therapy medicinal products (ATMPs) are drugs for human use for the treatment of chronic, degenerative, or life-threatening diseases that are based on genes, tissues, or cells. This article aimed to identify and critically review published economic analyses of ATMPs.

METHODS

A systematic review of economic analyses of ATMPs was undertaken. Study characteristics, design, sources of data, resources and unit costs, modeling and extrapolation methods, study results, and sensitivity analyses were assessed.

RESULTS

A total of 46 economic analyses of ATMP (from 45 articles) were included; 4 were cell therapy medicinal products, 33 gene therapy medicinal products, and 9 tissue-engineered products. 30 therapies had commercial marketing approval; 39 studies were cost-utility analysis, 5 were cost-effectiveness analysis, and 2 were cost only studies. Four studies predicted that the ATMP offered a step change in the management of the condition and 10 studies estimated that the ATMP would offer a lower mean cost.

CONCLUSIONS

Comparison with historical controls, pooling of data, and use of techniques such as mixture cure fraction models should be used cautiously. Sensitivity analyses should be used across a plausible range of prices. Clinical studies need to be designed to align with health technology assessment requirements, including generic quality of life, and payers should aim for clarity of criteria. Regulators and national payers should aim for compatibility of registers to allow interchange of data. Given the increasing reliance on industry-funded economic analyses, careful critical review is recommended.

Chondrocyte De-Differentiation: Biophysical Cues to Nuclear Alterations

Autologous chondrocyte implantation (ACI) is a cell therapy to repair cartilage defects. In ACI a biopsy is taken from a non-load bearing area of the knee and expanded in-vitro. The expansion process provides the benefit of generating a large number of cells required for implantation; however, during the expansion these cells de-differentiate and lose their chondrocyte phenotype. In this review we focus on examining the de-differentiation phenotype from a mechanobiology and biophysical perspective, highlighting some of the nuclear mechanics and chromatin changes in chondrocytes seen during the expansion process and how this relates to the gene expression profile. We propose that manipulating chondrocyte nuclear architecture and chromatin organization will highlight mechanisms that will help to preserve the chondrocyte phenotype.

Four cases report: Treatment of knee joint cartilage defects using autologous chondrocyte patch implantation

INTRODUCTION

Autologous chondrocyte implantation (ACI) is a crucial method for the treatment of defects in articular cartilage. However, the extant methods for the preparation of autologous chondrocyte patch are relatively complicated and money-consuming. Therefore, an efficient, reliable, easy-to-follow, and cost-effective technique is needed to overcome constraints. This case report aims to introduce an autologous chondrocyte patch fabrication technique to repair knee joint cartilage defects and report our typical cases with a 2-year follow-up.

CASE PRESENTATION

We described four cases in which patients complained of knee joint pain. According to radiological examination, the patients were diagnosed as knee joint cartilage defect. Arthroscopy and autologous chondrocyte patch implantation were performed as well as a 2-year follow up of patients. The autologous chondrocyte patch for knee joint cartilage repair was fabricated using a "sandwich" technique. The preoperative and postoperative knee function was evaluated by four subjective evaluation systems. MRI was performed for all patients to achieve more intuitionistic observation of the postoperative radiological changes of defect sites. The quality of repaired tissue was evaluated by Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART). Postoperative follow-up showed improvement in clinical and MOCART scores for all patients. However, one patient complained of knee joint pain after walking for a long time or recreational activities from 12- to 18-month postoperatively. The location of pain for this patient was not in accordance with the location of cartilage defect.

CONCLUSION

The patients undergoing autologous chondrocyte patch implantation demonstrated clinical improvement and good quality of repaired tissue postoperatively. The procedure is an efficient and cost-effective treatment for knee joint cartilage defect in this report. In addition, patients with osteoarthritis carry the risk of a poor outcome after the procedure, and whether to have a procedure should be considered carefully.

Evaluation of a co-culture of rapidly isolated chondrocytes and stem cells seeded on tri-layered collagen-based scaffolds in a caprine osteochondral defect model

Cartilage has poor regenerative capacity and thus damage to the joint surfaces presents a major clinical challenge. Recent research has focussed on the development of tissue-engineered and cell-based approaches for the treatment of cartilage and osteochondral injuries, with current clinically available cell-based approaches including autologous chondrocyte implantation and matrix-assisted autologous chondrocyte implantation. However, these approaches have significant disadvantages due to the requirement for a two-stage surgical procedure and an in vitro chondrocyte expansion phase which increases logistical challenges, hospital times and costs. In this study, we hypothesized that seeding biomimetic tri-layered scaffolds, with proven regenerative potential, with chondrocyte/infrapatellar fat pad stromal cell co-cultures would improve their regenerative capacity compared to scaffolds implanted cell-free. Rapid cell isolation techniques, without the requirement for long term in vitro culture, were utilised to achieve co-cultures of chondrocytes and stromal cells and thus overcome the limitations of existing cell-based techniques. Cell-free and cell-seeded scaffolds were implanted in osteochondral defects, created within the femoral condyle and trochlear ridge, in a translational large animal goat model. While analysis showed trends towards delayed subchondral bone healing in the cell-seeded scaffold group, by the 12 month timepoint the cell-free and cell-seeded groups yield cartilage and bone tissue with comparable quality and quantity. The results of the study reinforce the potential of the biomimetic tri-layered scaffold to repair joint defects but failed to demonstrate a clear benefit from the addition of the CC/FPMSC co-culture to this scaffold. Taking into consideration the additional cost and complexity associated with the cell-seeded scaffold approach, this study demonstrates that the treatment of osteochondral defects using cell-free tri-layered scaffolds may represent a more prudent clinical approach.

Biomaterial-Based Therapeutic Approaches to Osteoarthritis and Cartilage Repair Through Macrophage Polarization

There is an ever-increasing clinical and socioeconomic burden associated with cartilage lesions & osteoarthritis (OA). Its progression, chondrocyte death & hypertrophy are all facilitated by inflamed synovium & joint environment. Due to their capacity to switch between pro- & anti-inflammatory phenotypes, macrophages are increasingly being recognized as a key player in the healing process, which has been largely overlooked in the past. A biomaterial's inertness has traditionally been a goal while developing them in order to reduce the likelihood of adverse reactions from the host organism. A better knowledge of how macrophages respond to implanted materials has made it feasible to determine the biomaterial architectural parameters that control the host response & aid in effective tissue integration. Thus, this review summarizes novel therapeutic techniques for avoiding OA or increasing cartilage repair & regeneration that might be developed using new technologies tuning macrophages into desirable functional phenotypes.

Comparison of Autologous Osteoperiosteal and Osteochondral Transplantation for the Treatment of Large, Medial Cystic Osteochondral Lesions of the Talus

BACKGROUND

Autologous osteoperiosteal transplantation (AOPT) using graft harvested from the iliac crest is used to treat large cystic osteochondral lesions of the talus (OLTs). However, no studies have compared clinical and radiologic outcomes between AOPT and autologous osteochondral transplantation (AOCT) using graft harvested from the nonweightbearing zone of the femoral condyle of the ipsilateral knee in patients with large cystic OLTs.

PURPOSE

To compare clinical and radiologic outcomes between patients undergoing AOPT and those undergoing AOCT for large cystic OLTs.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Between March 2015 and March 2018, patients who underwent AOCT and AOPT to treat medial large cystic OLTs (>10 mm) were retrospectively evaluated. For comparability, the 2 groups were matched 1:1 based on their characteristics, including sex, age, body mass index, side of injury, follow-up period, and the preoperative cyst volume. After propensity score matching, 23 patients were enrolled in each group for the analysis. Clinical outcomes were assessed using the visual analog scale (VAS), the American Orthopaedic Foot & Ankle Society (AOFAS) score, and the Tegner score. Donor-site morbidity was recorded according to the symptoms, including pain, stiffness, swelling, and discomfort. In addition, the Lysholm score was used to assess the most common knee donor-site morbidity. Radiologic outcomes were evaluated using the magnetic resonance observation of cartilage repair tissue (MOCART) score, and the International Cartilage Regeneration & Joint Preservation Society (ICRS) score was obtained during second-look surgery.

RESULTS

The mean follow-up period was about 48 months. There were no significant differences in patient characteristics and lesion volumes between groups. Postoperative ankle pain VAS score, AOFAS score, and Tegner score were not significantly different between groups at final follow-up. Total donor-site morbidity (P = .004) and discomfort morbidity (P = .009) were significantly lower in the AOPT group than in the AOCT group. However, the Lysholm score showed no significant difference between the donor knee and the opposite knee (P = .503) in the AOCT group. The MOCART and ICRS scores were not significantly different between groups.

CONCLUSION

Clinical and radiologic outcomes of patients who underwent AOPT from the iliac crest were found to be comparable with those of patients who underwent AOCT from the ipsilateral knee for the treatment of medial large cystic OLTs. These results may be helpful for orthopaedic surgeons to decide appropriate treatments for patients with large cystic OLTs.

Magnetic resonance observation of cartilage repair tissue (MOCART) 2.0 for the evaluation of retropatellar autologous chondrocyte transplantation and correlation to clinical outcome

BACKGROUND

Matrix-associated chondrocyte transplantation (MACT) has become an established treatment option for cartilage defects.

OBJECTIVE

Three objectives were defined: first, to evaluate retropatellar cartilage grafts using Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) 2.0 score; second, to determine whether clinical outcome correlates with specific parameters or overall results; third, to screen those parameters for their ability to predict a clinical outcome of Delta IKDC ≥ 20 as a threshold for good clinical response at 12 months.

METHODS

38 patients were included of whom all underwent retropatellar MACT. MRI was performed 3, 6 and 12 months postoperatively. The clinical status was determined using International Knee Documentation Committee Subjective Form (IKDC). Correlations of MOCART 2.0 parameters and Delta IKDC scores were quantified by nonparametric Spearman's R. Those parameters with significant correlations (p < 0.05) were screened for their ability to predict a clinical outcome of Delta IKDC ≥ 20 at 12 months.

RESULTS

Significant correlations were identified for the parameters MOCART total _{6 months} (p < 0.05), Surface _{6 months} (p < 0.05), Surface _{12 months} (p < 0.05), Structure _{6 months} (p < 0.01), Structure _{12 months} (p < 0.05), Subchondral changes _{3 months} (p < 0.0001), Subchondral changes _{6 months} (p < 0.05) and Subchondral changes _{12 months} (p < 0.05). Among all MRI score parameters, Subchondral changes _{3 months} achieved the highest accuracy of 0.76 (0.62-0.86) in predicting Delta IKDC ≥ 20 after 12 months.

CONCLUSION

Some of the MOCART 2.0 parameters show significant correlation with Delta IKDC scores in the postoperative course after retropatellar MACT, which seems to depend on the time interval between surgery and MRI acquisition.

Layer-specific stem cell differentiation in tri-layered tissue engineering biomaterials: Towards development of a single-stage cell-based approach for osteochondral defect repair

Successful repair of osteochondral defects is challenging, due in part to their complex gradient nature. Tissue engineering approaches have shown promise with the development of layered scaffolds that aim to promote cartilage and bone regeneration within the defect. The clinical potential of implanting these scaffolds cell-free has been demonstrated, whereby cells from the host bone marrow MSCs infiltrate the scaffolds and promote cartilage and bone regeneration within the required regions of the defect. However, seeding the cartilage layer of the scaffold with a chondrogenic cell population prior to implantation may enhance cartilage tissue regeneration, thus enabling the treatment of larger defects. Here the development of a cell seeding approach capable of enhancing articular cartilage repair without the requirement for in vitro expansion of the cell population is explored. The intrinsic ability of a tri-layered scaffold previously developed in our group to direct stem cell differentiation in each layer of the scaffold was first demonstrated. Following this, the optimal chondrogenic cell seeding approach capable of enhancing the regenerative capacity of the tri-layered scaffold was demonstrated with the highest levels of chondrogenesis achieved with a co-culture of rapidly isolated infrapatellar fat pad MSCs (FPMSCs) and chondrocytes (CCs). The addition of FPMSCs to a relatively small number of CCs led to a 7.8-fold increase in the sGAG production over chondrocytes in mono-culture. This cell seeding approach has the potential to be delivered within a single-stage approach, without the requirement for costly in vitro expansion of harvested cells, to achieve rapid repair of osteochondral defects.

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Tri-layered scaffold capable of directing layer specific stem cell differentiation.

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Potential of cell seeding regimes to enhance chondrogenic repair explored.

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Optimal cell seeding regime was an infrapatellar fat pad MSC:chondrocyte coculture.

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Adding infrapatellar fat pad MSCs to chondrocytes led to >7-fold increase in sGAG.

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This cell-seeded scaffold has potential for rapid repair of osteochondral defects.

Algorithm for Treatment of Focal Cartilage Defects of the Knee: Classic and New Procedures

OBJECTIVE

To create a treatment algorithm for focal grade 3 or 4 cartilage defects of the knee using both classic and novel cartilage restoration techniques.

DESIGN

A comprehensive review of the literature was performed highlighting classic as well as novel cartilage restoration techniques supported by clinical and/or basic science research and currently being employed by orthopedic surgeons.

RESULTS

There is a high level of evidence to support the treatment of small to medium size lesions (<2-4 cm2) without subchondral bone involvement with traditional techniques such as marrow stimulation, osteochondral autograft transplant (OAT), or osteochondral allograft transplant (OCA). Newer techniques such as autologous matrix-induced chondrogenesis and bone marrow aspirate concentrate implantation have also been shown to be effective in select studies. If subchondral bone loss is present OAT or OCA should be performed. For large lesions (>4 cm2), OCA or matrix autologous chondrocyte implantation (MACI) may be performed. OCA is preferred over MACI in the setting of subchondral bone involvement while cell-based modalities such as MACI or particulated juvenile allograft cartilage are preferred in the patellofemoral joint.

CONCLUSIONS

Numerous techniques exist for the orthopedic surgeon treating focal cartilage defects of the knee. Treatment strategies should be based on lesion size, lesion location, subchondral bone involvement, and the level of evidence supporting each technique in the literature.

Prospective Outcomes of Cryopreserved Osteochondral Allograft for Patellofemoral Cartilage Defects at Minimum 2-Year Follow-up

OBJECTIVE

To analyze the clinical outcomes, knee function, and activity level of patients after treatment of full-thickness cartilage defects involving the patellofemoral compartment of the knee with cryopreserved osteochondral allograft.

DESIGN

Nineteen patients with cartilage defects involving the patellofemoral compartment were treated. The average age was 31 years (range 15-45 years), including 12 females and 7 males. Patients were prospectively followed using validated clinical outcome measures including Veterans RAND 12-item Health Survey (VR-12), International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Outcome Score (KOOS), and the Tegner activity scale. Graft incorporation was evaluated by magnetic resonance imaging (MRI) or second-look arthroscopy.

RESULTS

The cartilage defects included the patella (n = 16) and the femoral trochlea (n = 3). Mean VR-12 scores increased from 31.6 to 46.3 (P < 0.01), mean IKDC increased from 40.0 to 69.7 (P < 0.01), mean KOOS increased from 53.9 to 80.2 (P < 0.01), and mean Tegner scores increased from 3.0 to 4.9 (P < 0.01), at average follow-up of 41.9 months (range 24-62 months). Of the 3 patients who underwent second-look arthroscopy, all demonstrated a well-incorporated graft. Mean MOCART score for the 6 patients with follow-up MRI was 62.5 (range 25-85). The reoperation rate was 21.1% and 2 patients (12.5%) experienced progressive patellofemoral osteoarthritis requiring conversion to patellofemoral arthroplasty.

CONCLUSION

Patients with unipolar cartilage defects involving the patellofemoral compartment of the knee can have positive outcomes at minimum 2-year follow-up after surgical treatment with a cryopreserved osteochondral allograft when concomitant pathology is also addressed, but the reoperation rate is high and bipolar cartilage lesions may increase the failure rate.

Costal Chondrocyte-Derived Pellet-Type Autologous Chondrocyte Implantation versus Microfracture for Repair of Articular Cartilage Defects: A Prospective Randomized Trial

OBJECTIVE

To compare the efficacy and safety of costal chondrocyte-derived pellet-type autologous chondrocyte implantation (CCP-ACI) with microfracture (MFx) for repair of articular cartilage defects of the knee.

DESIGN

Thirty subjects with an International Cartilage Repair Society (ICRS) grade 3 to 4 chondral defect (2-10 cm² in area; ≤4 cm³ in volume) were randomized at a ratio of 2:1 (CCP-ACI:MFx). Twenty patients were allocated in the CCP-ACI group and 10 patients in the MFx group. CCP-ACI was performed by harvesting costal cartilage at least 4 weeks before surgery. Implantation was performed without any marrow stimulation. Efficacy and safety were assessed at weeks 8, 24, and 48 after surgery according to the magnetic resonance observation of cartilage repair tissue (MOCART) score and clinical outcomes.

RESULTS

MOCART scores improved from baseline to 24 and 48 weeks postoperatively in both treatment groups. The improvement in MOCART scores in the CCP-ACI group was significantly greater than that in the MFx group at 24 and 48 weeks (39.1 vs 21.8 and 43.0 vs 24.8, respectively). The proportions of complete defect repair and complete integration were significantly higher in the CCP-ACI group than the MFx group at 48 weeks. Improvement in Lysholm score and KOOS subscores, including Function (Sports and Recreational Activity) and knee-related quality of life was significantly greater in the CCP-ACI group than the MFx group at 48 weeks (35.4 vs 31.5, 35.7 vs 28.5, and 27.9 vs 11.6, respectively).

CONCLUSION

Treatment of cartilage defects with CCP-ACI yielded satisfactory cartilage tissue repair outcomes, with good structural integration with native cartilage tissue shown by magnetic resonance imaging at 24 and 48 weeks after surgery.

LEVEL OF EVIDENCE

Level 1: Randomized controlled study.

Impaction Bone Grafting for Treatment of Unstable Osteochondritis Dissecans (OCD) Lesions

Although treatment options for unstable and unsalvageable large osteochondral lesions have largely been limited to autologous chondrocyte implantation (ACI) and osteochondral allografts, isolated impaction bone grafting represents a cost-friendly alternative, with predictable outcomes comparable to other options. Furthermore, the procedure can be completed in a single stage on an elective basis. We present our technique for impaction bone grafting of unstable osteochondritis dissecans (OCD) using either cancellous autograft or allograft.

Role of Scaffolds, Subchondral, Intra-Articular Injections of Fresh Autologous Bone Marrow Concentrate Regenerative Cells in Treating Human Knee Cartilage Lesions: Different Approaches and Different Results

The value of bone marrow aspirate concentrates for treatment of human knee cartilage lesions is unclear. Most of the studies were performed with intra-articular injections. However, subchondral bone plays an important role in the progression of osteoarthritis. We investigated by a literature review whether joint, subchondral bone, or/and scaffolds implantation of fresh autologous bone marrow aspirate concentrated (BMAC) containing mesenchymal stem cells (MSCs) would improve osteoarthritis (OA). There is in vivo evidence that suggests that all these different approaches (intra-articular injections, subchondral implantation, scaffolds loaded with BMAC) can improve the patient. This review analyzes the evidence for each different approach to treat OA. We found that the use of intra-articular injections resulted in a significant relief of pain symptoms in the short term and was maintained in 12 months. However, the clinical trials indicate that the application of autologous bone marrow concentrates in combination with scaffolds or in injection in the subchondral bone was superior to intra-articular injection for long-term results. The tendency of MSCs to differentiate into fibrocartilage affecting the outcome was a common issue faced by all the studies when biopsies were performed, except for scaffolds implantation in which some hyaline cartilage was found. The review suggests also that both implantation of subchondral BMAC and scaffolds loaded with BMAC could reduce the need for further surgery.

Health Economic Evaluations of Hip and Knee Interventions in Orthopaedic Sports Medicine: A Systematic Review and Quality Assessment

BACKGROUND

The economic burden of musculoskeletal diseases is substantial and growing. Economic evaluations compare costs and health benefits of interventions simultaneously to help inform value-based care; thus, it is crucial to ensure that studies are using appropriate methodology to provide valid evidence on the cost-effectiveness of interventions. This is particularly the case in orthopaedic sports medicine, where several interventions of varying costs are available to treat common hip and knee conditions.

PURPOSE

To summarize and evaluate the quality of economic evaluations in orthopaedic sports medicine for knee and hip interventions and identify areas for quality improvement.

STUDY DESIGN

Systematic review; Level of evidence, 3.

METHODS

The Medline, AMED, OVID Health Star, and EMBASE databases were searched from inception to March 1, 2020, to identify economic evaluations that compared ≥2 interventions for hip and/or knee conditions in orthopaedic sports medicine. We assessed the quality of full economic evaluations using the Quality of Health Economic Studies (QHES) tool, which consists of 16 questions for a total score of 100. We classified studies into quartiles based on QHES score (extremely poor quality to high quality) and we evaluated the frequency of studies that addressed each of the 16 QHES questions.

RESULTS

A total of 93 studies were included in the systematic review. There were 41 (44%) cost analyses, of which 21 (51%) inappropriately concluded interventions were cost-effective. Only 52 (56%) of the included studies were full economic evaluations, although 40 of these (77%) fell in the high-quality quartile. The mean QHES score was 83.2 ± 19. Authors consistently addressed 12 of the QHES questions; questions that were missed or unclear were related to statistical uncertainty, appropriateness of costing methodology, and discussion of potential biases. The most frequently missed question was whether the cost perspective of the analysis was stated and justified.

CONCLUSION

The number of studies in orthopaedic sports medicine is small, despite their overall good quality. Yet, there are still many highly cited studies based on low-quality or partial economic evaluations that are being used to influence clinical decision-making. Investigators should follow international health economic guidelines for study design and critical appraisal of studies to further improve quality.

Cartiform Implantation for focal cartilage defects in the knee: A 2-year clinical and magnetic resonance imaging follow-up study

The purpose of this study was to evaluate clinical and magnetic resonance imaging (MRI) outcomes in patients who underwent cryopreserved viable osteochondral allograft (CVOCA) implantation for focal cartilage defects in the knee at a minimum of 2-years postoperatively. This is a retrospective follow-up study of twelve patients who underwent CVOCA implantation from 2013 to 2015 by a single surgeon for a International Cartilage Repair Society (ICRS) grade 3 or 4 chondral defect. Patient-reported outcome (PRO) measurements and MRI were obtained 2-years postoperatively. Collected PRO measures included: International Knee Documentation Committee (IKDC) form; Visual Analog Scale (VAS) pain score; Veterans RAND 12-Item Health Survey (VR-12); Knee Injury and Osteoarthritis Outcome Score (KOOS); and Western Ontario McMaster Universities Osteoarthritis Index (WOMAC). Patients completed a standard return to work and sports/recreation survey. A blinded, fellowship-trained musculoskeletal radiologist independently evaluated each MRI to determine the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. Mean follow-up was 2.1 years (2.0-2.3). There were 6 women and 6 men with a mean age of 46.2 ± 11.9 years. Mean PRO scores were: IKDC 72.6 ± 17.4; VAS 2.9 ± 2.8; WOMAC 84.2 ± 15.1; KOOS- Pain 83.8 ± 18.5, Symptoms 77.6 ± 16.0, ADL 88.0 ± 16.9, Sports/Rec 67.7 ± 33.3, QOL 54.8 ± 24.2; and VR-12 PCS 45.0 ± 8.5 and MCS 51.1 ± 9.5. The mean MOCART score was 59.5 ± 12.9. To our knowledge, this is the largest study to report clinical and MRI outcomes of CVOCA implantation in the knee. With positive functional outcomes and lack of failures at 2-year follow-up, CVOCA is a promising treatment option for focal chondral defects in the knee.

STUDY DESIGN

Retrospective case series, Level of evidence 4.

Management of Large Focal Chondral and Osteochondral Defects in the Knee

Large, focal articular cartilage defects of the knee (> 4 cm²) can be a source of significant morbidity and often require surgical intervention. Patient- and lesion-specific factors must be identified when evaluating a patient with an articular cartilage defect. In the management of large cartilage defects, the two classically utilized cartilage restoration procedures are osteochondral allograft (OCA) transplantation and cell therapy, or autologous chondrocyte implantation (ACI). Alternative techniques that are available or currently in clinical trials include a hyaluronan-based scaffold plus bone marrow aspirate concentrate, a third-generation autologous chondrocyte implant, and an aragonite-based scaffold. In this review, we will focus on OCA and ACI as the mainstay in management of large chondral and osteochondral defects of the knee. We will discuss the techniques and associated clinical outcomes for each, while including a brief mention of alternative treatments. Overall, cartilage restoration techniques have yielded favorable clinical outcomes and can be successfully employed to treat these challenging large focal lesions.

Human Synovial Mesenchymal Stem Cells Good Manufacturing Practices for Articular Cartilage Regeneration

Background: Cartilage restoration is a desperately needed bridge for patients with symptomatic cartilage lesions. Chondral lesion is a pathology with high prevalence, reaching as much as 63% of general population and 36% among athletes. Despite autologous chondrocyte implantation versatility, it still fails to fully reproduce hyaline articular cartilage characteristics. Mesenchymal stem cells (MSCs) may be isolated from various known tissues, including discarded fragments at arthroscopy such as synovial membrane. Choice of harvesting site is motivated by MSCs' abilities to modulate immunologic and inflammatory response through paracrine communication. Synovial MSCs have a greater proliferation and strong chondrogenic potential than bone and adipose MSCs and a less hypertrophic differentiation than bone MSCs. Good manufacturing practice (GMP) laboratory techniques for human clinical trials are still novel. To our knowledge, there are only two clinical trials in humans published since today. Purpose: Therefore, this work aimed to isolate and characterize synovial MSCs and evaluated their differentiation properties according to GMP standards. Materials and Methods: One-gram tissue sample from three patients of synovia was harvested at the beginning of arthroscopy surgery. MSCs were isolated, expanded, and characterized by flow cytometry. Results: It was possible to isolate and expand MSCs cultures from synovia, characterize MSCs by flow cytometry using proper monoclonal antibodies, and differentiate MSCs by coloring technique after chondrogenic, adipogenic, and osteogenic differentiations. Cartilage treatment may benefit from these tissue engineering protocols since arthroscopic procedures are routinely performed for different purposes in a previous stage and a favorable chondronegic differentiation cell lineage may be collected and stored in a less invasive way. Conclusion: Laboratory protocols established according to presented GMP were able to isolate and characterize MSCs obtained from synovia. Impact Statement Articular cartilage restoration is a desperately needed bridge for patients with symptomatic cartilage lesions and it rises as a socioeconomic issue with a considerable economic burden. Synovial mesenchymal stem cells (MSCs) have a greater proliferation rate and strong chondrogenic potential than bone and adipose MSCs and a less hypertrophic differentiation than bone MSCs. To our knowledge, there are only two human clinical trials with good manufacturing practice laboratory techniques for synovial MSCs harvesting and differentiation. Cartilage treatment may benefit from these tissue engineering protocols since arthroscopic procedures are routinely performed for different purposes in a previous stage.

A systematic review of economic evaluations of advanced therapy medicinal products

Aims

Advanced therapy medicinal products (ATMPs) represent a new category of medicinal products with a potential for transformative improvements in health outcomes but at exceptionally high prices. Routine adoption of ATMPs requires robust evidence of their cost‐effectiveness.

Methods

A systematic literature review of economic evaluations of ATMPs, including gene therapies, somatic cell therapies and tissue‐engineered products, was conducted. Literature was searched using MedLine, Embase, PubMed, Cochrane Register, the NHS Economic Evaluation Database and the grey literature of health technology assessment organisations with search terms relating to ATMPs and economic evaluations. Titles were screened independently by 2 reviewers. Articles deemed to meet the inclusion criteria were screened independently on abstract, and full texts reviewed. Study findings were appraised critically.

Results

4514 articles were identified, of which 23 met the inclusion criteria. There was some evidence supporting the cost‐effectiveness of: chimeric antigen receptor T‐cell therapy axicabtagene–ciloleucel (Yescarta), embryonic neural stem cells, tumour infiltrating lymphocytes, in vitro expanded myoblast, autologous chondrocyte implantation, ex vivo gene therapy (Strimvelis) and voretigene neparvovec (Luxturna). However, estimates of cost‐effectiveness were associated with significant uncertainty and high likelihood of bias, resulting from largely unknown long‐term outcomes, a paucity of evidence on health state utilities and extensive modelling assumptions.

Conclusion

There are critical limitations to the economic evidence for ATMPs, most notably in relation to evidence on the durability of treatment effect, and the reliability of opinion‐based assumptions necessary when evidence is absent.

Macrophage: A Potential Target on Cartilage Regeneration

Cartilage lesions and osteoarthritis (OA) presents an ever-increasing clinical and socioeconomic burden. Synovial inflammation and articular inflammatory environment are the key factor for chondrocytes apoptosis and hypertrophy, ectopic bone formation and OA progression. To effectively treat OA, it is critical to develop a drug that skews inflammation toward a pro-chondrogenic microenvironment. In this narrative and critical review, we aim to see the potential use of immune cells modulation or cell therapy as therapeutic alternatives to OA patients. Macrophages are immune cells that are present in synovial lining, with different roles depending on their subtypes. These cells can polarize to pro-inflammatory (M1) and anti-inflammatory (M2) phenotypes, being the latter associated with wound-healing by the production of ARG-1 and pro-chondrogenic cytokines, such as IL-10, IL-1RA, and TGF-b. Emerging evidence reveals that macrophage shift can be determined by several stimuli, apart from the conventional in vitro IL-4, IL-13, and IL-10. Evidences show the potential of physical exercise to induce type 2 response, favoring M2 polarization. Moreover, macrophages in contact with oxLDL have effect on the production of anabolic mediators as TGF-b. In the same direction, type II collagen, that plays a critical role in development and maturation process of chondrocytes, can also induce M2 macrophages, increasing TGF-b. The mTOR pathway activation in macrophages was shown to be able to polarize macrophages in vitro, though further studies are required. The possibility to use mesenchymal stem cells (MSCs) in cartilage restoration have a more concrete literature, besides, MSCs also have the capability to induce M2 macrophages. In the other direction, M1 polarized macrophages inhibit the proliferation and viability of MSCs and impair their ability to immunosuppress the environment, preventing cartilage repair. Therefore, even though MSCs therapeutic researches advances, other sources of M2 polarization are attractive issues, and further studies will contribute to the possibility to manipulate this polarization and to use it as a therapeutic approach in OA patients.

Cost-efficacy of Knee Cartilage Defect Treatments in the United States

BACKGROUND

Multiple knee cartilage defect treatments are available in the United States, although the cost-efficacy of these therapies in various clinical scenarios is not well understood.

PURPOSE/HYPOTHESIS

The purpose was to determine cost-efficacy of cartilage therapies in the United States with available mid- or long-term outcomes data. The authors hypothesized that cartilage treatment strategies currently approved for commercial use in the United States will be cost-effective, as defined by a cost <$50,000 per quality-adjusted life-year over 10 years.

STUDY DESIGN

Systematic review.

METHODS

A systematic search was performed for prospective cartilage treatment outcome studies of therapies commercially available in the United States with minimum 5-year follow-up and report of pre- and posttreatment International Knee Documentation Committee subjective scores. Cost-efficacy over 10 years was determined with Markov modeling and consideration of early reoperation or revision surgery for treatment failure.

RESULTS

Twenty-two studies were included, with available outcomes data on microfracture, osteochondral autograft, osteochondral allograft (OCA), autologous chondrocyte implantation (ACI), and matrix-induced ACI. Mean improvement in International Knee Documentation Committee subjective scores at final follow-up ranged from 17.7 for microfracture of defects >3 cm² to 36.0 for OCA of bipolar lesions. Failure rates ranged from <5% for osteochondral autograft for defects requiring 1 or 2 plugs to 46% for OCA of bipolar defects. All treatments were cost-effective over 10 years in the baseline model if costs were increased 50% or if failure rates were increased an additional 15%. However, if efficacy was decreased by a minimum clinically important amount, then ACI (periosteal cover) of femoral condylar lesions ($51,379 per quality-adjusted life-year), OCA of bipolar lesions ($66,255) or the patella ($66,975), and microfracture of defects >3 cm² ($127,782) became cost-ineffective over 10 years.

CONCLUSION

Currently employed treatments for knee cartilage defects in the United States are cost-effective in most clinically acceptable applications. Microfracture is not a cost-effective initial treatment of defects >3 cm². OCA transplantation of the patella or bipolar lesions is potentially cost-ineffective and should be used judiciously.

Long-term Clinical Outcomes of One-Stage Cartilage Repair in the Knee With Hyaluronic Acid-Based Scaffold Embedded With Mesenchymal Stem Cells Sourced From Bone Marrow Aspirate Concentrate

BACKGROUND

Cell-based cartilage repair performed as a single-stage procedure is an important advancement in the treatment of full-thickness cartilage injury and has potential for widespread clinical use.

PURPOSE

To investigate the long-term clinical outcomes of cartilage repair in the knee with a hyaluronic acid-based scaffold embedded with bone marrow aspirate concentrate (HA-BMAC) for the treatment of full-thickness cartilage injury.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients underwent treatment of full-thickness chondral injury in the knee with HA-BMAC and were followed prospectively for a minimum of 6 years. Clinical outcomes were examined with patient-reported scoring instruments that consisted of the Tegner Activity Scale, International Knee Documentation Committee (IKDC) subjective score, visual analog scale, and Knee injury and Osteoarthritis Outcome Score (KOOS). Comparative analysis of pre- and postoperative scores was performed, and the effects of patient age, body mass index, lesion size, number of treated lesions, and concurrent treatment with associated procedures were examined.

RESULTS

Twenty-three patients (mean age, 48.5 years) were followed prospectively for a mean 8 years (range, 6-10 years). Median cartilage lesion size was 6.5 cm² (range, 2-27 cm²). At final follow-up, median Tegner, visual analog scale, and IKDC subjective scores were 4, 0.3, and 85, respectively. Final median KOOS subset scores were as follows: Pain, 94; Symptoms, 89; Activities of Daily Living, 99; Sports/Recreation, 85; and Quality of Life, 85. All scores were significantly increased at final follow-up ( P < .001). Comparable median outcome scores were demonstrated after categorization of patients by age, lesion size, treatment of multiple lesions, treatment of multiple knee compartments, and treatment by associated procedures. Rank correlation analysis demonstrated a negative correlation between patient age and final outcome scores of the IKDC, Tegner, and KOOS subsets of Pain, Activities of Daily Living, and Sports/Recreation. No associations were identified between body mass index or lesion size and outcome scores.

CONCLUSION

Repair of full-thickness cartilage injury in the knee with a HA-BMAC provides good to excellent clinical outcomes at long-term follow-up in the treatment of small to large lesions. Cartilage repair with HA-BMAC leads to comparatively successful long-term outcomes in the treatment of small or large lesions, single or multiple lesions, and lesions in 1 or 2 compartments, as well as in cases of associated lesion treatment. While good outcomes can be expected among treated patients >45 years of age, outcomes may be comparatively more successful in younger patients.

Autologous chondrocyte implantation in the knee: systematic review and economic evaluation

BACKGROUND

The surfaces of the bones in the knee are covered with articular cartilage, a rubber-like substance that is very smooth, allowing frictionless movement in the joint and acting as a shock absorber. The cells that form the cartilage are called chondrocytes. Natural cartilage is called hyaline cartilage. Articular cartilage has very little capacity for self-repair, so damage may be permanent. Various methods have been used to try to repair cartilage. Autologous chondrocyte implantation (ACI) involves laboratory culture of cartilage-producing cells from the knee and then implanting them into the chondral defect.

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of ACI in chondral defects in the knee, compared with microfracture (MF).

DATA SOURCES

A broad search was done in MEDLINE, EMBASE, The Cochrane Library, NHS Economic Evaluation Database and Web of Science, for studies published since the last Health Technology Assessment review.

REVIEW METHODS

Systematic review of recent reviews, trials, long-term observational studies and economic evaluations of the use of ACI and MF for repairing symptomatic articular cartilage defects of the knee. A new economic model was constructed. Submissions from two manufacturers and the ACTIVE (Autologous Chondrocyte Transplantation/Implantation Versus Existing Treatment) trial group were reviewed. Survival analysis was based on long-term observational studies.

RESULTS

Four randomised controlled trials (RCTs) published since the last appraisal provided evidence on the efficacy of ACI. The SUMMIT (Superiority of Matrix-induced autologous chondrocyte implant versus Microfracture for Treatment of symptomatic articular cartilage defects) trial compared matrix-applied chondrocyte implantation (MACI^®) against MF. The TIG/ACT/01/2000 (TIG/ACT) trial compared ACI with characterised chondrocytes against MF. The ACTIVE trial compared several forms of ACI against standard treatments, mainly MF. In the SUMMIT trial, improvements in knee injury and osteoarthritis outcome scores (KOOSs), and the proportion of responders, were greater in the MACI group than in the MF group. In the TIG/ACT trial there was improvement in the KOOS at 60 months, but no difference between ACI and MF overall. Patients with onset of symptoms < 3 years' duration did better with ACI. Results from ACTIVE have not yet been published. Survival analysis suggests that long-term results are better with ACI than with MF. Economic modelling suggested that ACI was cost-effective compared with MF across a range of scenarios.

LIMITATIONS

The main limitation is the lack of RCT data beyond 5 years of follow-up. A second is that the techniques of ACI are evolving, so long-term data come from trials using forms of ACI that are now superseded. In the modelling, we therefore assumed that durability of cartilage repair as seen in studies of older forms of ACI could be applied in modelling of newer forms. A third is that the high list prices of chondrocytes are reduced by confidential discounting. The main research needs are for longer-term follow-up and for trials of the next generation of ACI.

CONCLUSIONS

The evidence base for ACI has improved since the last appraisal by the National Institute for Health and Care Excellence. In most analyses, the incremental cost-effectiveness ratios for ACI compared with MF appear to be within a range usually considered acceptable. Research is needed into long-term results of new forms of ACI.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42014013083.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

High Short-Term Failure Rate Associated With Decellularized Osteochondral Allograft for Treatment of Knee Cartilage Lesions

PURPOSE

To report the short-term clinical and radiographic outcomes following the use of decellularized osteochondral (OC) allograft plugs in the treatment of distal femoral OC lesions.

METHODS

An Institutional Review Board-approved database with prospectively collected data was used to identify patients treated with the decellularized OC allograft plugs implant. Demographic information, patient-reported outcomes, magnetic resonance imaging (MRI), and the number and type of reoperations were assessed. Failure was defined as revision surgery with removal of the implant. Patients were evaluated pre- and postoperatively using the Short Form-36, Activity of Daily Living Score, International Knee Documentation Committee Subjective Evaluation, Cincinnati Knee Rating System, and Marx Activity Scale. MRIs were evaluated using the OsteoChondral Allograft MRI Scoring System.

RESULTS

Thirty-four patients were identified, with a mean age of 45 (±11.9) years; 71% were male. Fifteen (44%) patients had undergone prior ipsilateral surgical intervention. Mean defect size was 4 (±1.5) cm², and median number of allografts per knee was 2 (range, 1-5). Mean follow-up duration was 15.5 months (range, 6-24). Ten patients (29%) required revision surgery with removal of the implant. Implant survivorship was 61% at 2 years. Female gender was independently predictive of failure, with a hazard ratio of 9.4 (95% confidence interval [CI], 2.0-58.9; P = .005). Defect size was also independently predictive of failure, with a hazard ratio of 1.9 per 1 cm² increase (95% CI, 1.2-3.1; P = .005). MRIs obtained at 1 year postoperatively demonstrated significantly improved osseous integration (P = .0086) and opposing cartilage (P = .019) in the nonfailure group as compared with the failure group.

CONCLUSIONS

Based on the high short-term failure rate observed in this study, the authors advise that a decellularized OC allograft plugs implant should be used with caution in the treatment of OC lesions of the knee, as similar outcomes have not been noted with other cartilage restoration techniques. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Comparative efficacy of cartilage repair procedures in the knee: a network meta-analysis

PURPOSE

While numerous randomized controlled trials have compared surgical treatments for cartilage defects of the knee, the comparative efficacy of these treatments is still poorly understood. The goal of this network meta-analysis was to synthesize these randomized data into a comprehensive model allowing pairwise comparisons of all treatment options and treatment rankings based on multiple measures of efficacy. We hypothesized that advanced chondral procedures would have improved outcomes when compared to microfracture.

METHODS

The MEDLINE, COCHRANE and EMBASE databases were searched systematically up to January 2015. The primary outcome was re-operation measured at 2, 5 and 10 years. Secondary outcomes included Tegner and Lysholm scores, the presence of hyaline cartilage on post-operative biopsy and graft hypertrophy. A random-effects network meta-analysis was performed, and the results are presented as odds ratios and mean differences with 95 % CIs. We ranked the comparative effects of all treatments with surface under the cumulative ranking probabilities.

RESULTS

Nineteen RCT from 15 separate cohorts including 855 patients were eligible for inclusion. No differences were seen in re-operation rates at 2 years. At 5 years osteochondral autografts (OC Auto) had a lower re-operation rate than microfracture (OR 0.03, 95 % CI 0.00-0.49), and at 10 years OC Auto had a lower re-operation rate than microfracture (OR 0.34, 95 % CI 0.12-0.92), but a higher re-operation rate than second-generation ACI (OR 5.81, 95 % CI 2.33-14.47). No significant differences in Tegner or Lysholm scores were seen at 2 years. Functional outcome data at 5 and 10 years were not available. Hyaline repair tissue was more common with OC Auto (OR 16.13, 95 % CI 2.80-92.91) and 2nd generation ACI (OR 7.69, 95 % CI 1.17-50) than microfracture, though the clinical significance of this is unknown. Second-generation ACI (OR 0.12, 95 % CI 0.02-0.59) and MACI (OR 0.13, 95 % CI 0.03-0.59) had significantly lower rates of graft hypertrophy than first-generation ACI. Second-generation ACI, OC Auto and MACI were the highest ranked treatments (in order) when all outcome measures were included.

CONCLUSIONS

Microfracture and advanced cartilage repair techniques have similar re-operation rates and functional outcomes at 2 years. However, advanced repair techniques provide higher-quality repair tissue and might afford lower re-operation rates at 5 and 10 years.

LEVEL OF EVIDENCE

Meta-analysis studies, Level I.

Viable Osteochondral Allograft for the Treatment of a Full-Thickness Cartilage Defect of the Patella

Isolated cartilage defects can lead to significant pain and disability, prompting the development of a number of options for restorative treatment. Each method has advantages and limitations, and no single technique has gained widespread use. We present a technique for implantation of a cryopreserved osteochondral allograft (Cartiform) for the treatment of full-thickness cartilage defects. Cartiform is a cryopreserved osteochondral allograft composed of chondrocytes, chondrogenic growth factors, and extracellular matrix proteins. This implant allows for regenerative treatment of full-thickness cartilage lesions in a single surgical procedure.

Suture Button Fixation Versus Syndesmotic Screws in Supination-External Rotation Type 4 Injuries: A Cost-Effectiveness Analysis

BACKGROUND

In stress-positive, unstable supination-external rotation type 4 (SER IV) ankle fractures, implant selection for syndesmotic fixation is a debated topic. Among the available syndesmotic fixation methods, the metallic screw and the suture button have been routinely compared in the literature. In addition to strength of fixation and ability to anatomically restore the syndesmosis, costs associated with implant use have recently been called into question.

PURPOSE

This study aimed to examine the cost-effectiveness of the suture button and determine whether suture button fixation is more cost-effective than two 3.5-mm syndesmotic screws not removed on a routine postoperative basis.

STUDY DESIGN

Economic and decision analysis; Level of evidence, 2.

METHODS

Studies with the highest evidence levels in the available literature were used to estimate the hardware removal and failure rates for syndesmotic screws and suture button fixation. Costs were determined by examining the average costs for patients who underwent surgery for unstable SER IV ankle fractures at a single level-1 trauma institution. A decision analysis model that allowed comparison of the 2 fixation methods was developed.

RESULTS

Using a 20% screw hardware removal rate and a 4% suture button hardware removal rate, the total cost for 2 syndesmotic screws was US$20,836 and the total effectiveness was 5.846. This yielded a total cost of $3564 per quality-adjusted life-year (QALY) over an 8-year time period. The total cost for suture button fixation was $19,354 and the total effectiveness was 5.904, resulting in a total cost of $3294 per QALY over the same time period. A sensitivity analysis was then conducted to assess suture button fixation costs as well as screw and suture button hardware removal rates. Other possible treatment scenarios were also examined, including 1 screw and 2 suture buttons for operative fixation of the syndesmosis. To become more cost-effective, the screw hardware removal rate would have to be reduced to less than 10%. Furthermore, fixation with a single suture button continued to be the dominant treatment strategy compared with 2 suture buttons, 1 screw, and 2 screws for syndesmotic fixation.

CONCLUSION

This cost-effectiveness analysis suggests that for unstable SER IV ankle fractures, suture button fixation is more cost-effective than syndesmotic screws not removed on a routine basis. Suture button fixation was a dominant treatment strategy, because patients spent on average $1482 less and had a higher quality of life by 0.058 QALYs compared with patients who received fixation with 2 syndesmotic screws. Assuming that functional outcomes and failure rates were equivalent, screw fixation only became more cost-effective when the screw hardware removal rate was reduced to less than 10% or when the suture button cost exceeded $2000. In addition, fixation with a single suture button device proved more cost-effective than fixation with either 1 or 2 syndesmotic screws.

Incomplete defect filling after third generation autologous chondrocyte implantation

INTRODUCTION

Third generation autologous chondrocyte implantation (ACI) is a suitable method for the treatment of cartilage defects in the knee joint. However, knowledge about the development of graft thickness and the clinical relevance of incomplete defect filling in the postoperative course is low. This prospective study analyses the graft integration into the surrounding cartilage, with special consideration of the graft thickness.

MATERIAL AND METHODS

A total of 71 consecutive patients with 79 cartilage defects were treated with third generation autologous chondrocyte implantation (NOVOCART 3D) in the knee. Follow-up magnetic resonance imaging (MRI) was performed at 0.25, 0.5, 1 and 2 years. Graft thickness was measured compared to the surrounding healthy cartilage. The International Knee Documentation Committee (IKDC) scoring system and the visual analogue scale (VAS) were used for clinical evaluation. Cartilage defect filling was classified as the percentage of the surrounding cartilage.

RESULTS

The average graft thickness showed a significant increase between 3 and 6 months after autologous chondrocyte implantation. Incomplete defect filling occurred in 44 (55.7%) cases. Of these, 33 cases showed incomplete defect filling grade I (> 75%), 10 cases were grade II (> 50%) and one case grade III (> 25%). Incomplete defect filling grade IV (< 25%) was not observed. Incomplete defect filling occurred significantly more often in women (p = 0.021), without worse clinical results.

CONCLUSIONS

Graft thickness after third generation autologous chondrocyte implantation shows increasing graft thickness over the period of 2 years postoperatively. A high rate of incomplete defect filling in the surrounding cartilage was observed, without worse clinical results.

Outcomes following impaction bone grafting for treatment of unstable osteochondritis dissecans

BACKGROUND

Many methods have been proposed to treat unstable osteochondritis dissecans (OCD). Our purpose is to report outcomes in a cohort of patients undergoing impaction bone grafting for treatment of knee OCD.

METHODS

Patients undergoing impaction bone grafting for knee OCD between 1998 and 2011 were contacted and stratified into (a) those who have undergone subsequent surgery on the affected knee and (b) those who have not had revision surgery performed on the affected knee since the impaction bone grafting procedure. For those not undergoing another procedure, physical examination, radiographs, MRI, and functional outcomes (SF12, Tegner, Activity Rating Scale, and IKDC) were obtained.

RESULTS

Of nine patients (10 knees) undergoing the procedure, seven (eight knees) were available for follow-up. Three had revision surgery. One had debridement due to surface overgrowth and had no symptoms 43months following debridement, while two had osteochondral allograft and autograft procedures at three and 10years after initial surgery, respectively. Four patients did not require a revision surgical procedure at average follow-up of 55.4months (range, 21-116months). All had complete MRI fill of the cartilaginous defect with less than 50% of surface irregularity and redeveloped the tidemark and a heterogeneous cartilaginous surface. Follow-up Tegner, ARS, and SF12-PCS averaged 6.8, 67.5, and 56.6, respectively. All four had good/excellent IKDC results.

CONCLUSION

Impaction bone grafting can reliably restore osteocartilaginous defect produced by OCD and is a readily available and less-expensive option in treating OCD lesions. Further investigation is necessary to determine the long-term durability of the results. Level IV - Case series.

Patients Scheduled for Chondrocyte Implantation Treatment with MACI Have Larger Defects than Those Enrolled in Clinical Trials

OBJECTIVE

To compare characteristics for patients scheduled for autologous chondrocyte implantation with matrix-assisted chondrocyte implantation (MACI) with those enrolled in clinical trials and to describe differences in patient selection between countries.

DESIGN

Anonymized data from patients scheduled for MACI treatment in the knee in Europe and Australia/Asia were obtained from the Genzyme/Sanofi database. Average age, defect size, and male-female ratio were analyzed and compared by country. Clinical cohort studies and prospective comparative trials using autologous chondrocyte implantation and related treatments were identified and weighted average age, weighted defect size, and male-female ratio were analyzed and compared with data from the database.

RESULTS

From the database 2,690 patients were included with mean age 33.7 years and male-female ratio of 67:33. Mean defect size was 5.64 cm(2) and 70% of the defects were 3 to 10 cm(2). There were significant differences between patients' mean defect sizes between countries. Sixty-nine studies (57 cohorts and 12 prospective comparative trials) with a total of 5,449 patients were identified. The combined weighted mean age was 34.2 years, and the combined weighted mean defect size was 4.89 cm(2). Patients scheduled for MACI had significantly larger defects that those included in clinical trials. There was no significant difference in age. No differences were found between cohorts and prospective comparative trials.

CONCLUSION

The vast majority of patients scheduled for autologous chondrocyte implantation with MACI have chondral defect comparable to that generally recommended, but differences exist between countries. Patients enrolled in clinical trials have significantly smaller defects than those undergoing treatment outside controlled trials.

Early Clinical Outcomes Associated with a Novel Osteochondral Allograft Transplantation System in the Knee

Background. Osteochondral defects of the knee are a common finding at the time of arthroscopic intervention. Purpose/Hypothesis. To report our outcomes after utilizing a new technique of osteochondral allograft transplantation for focal cartilage defects. Study Design. Case series. Methods. All patients treated with osteochondral allograft transplantation with a Zimmer Chondrofix plug (Zimmer Inc., Warsaw, IN) for focal cartilage defects over a 12-month period were followed up at a minimum of 24 months. Failures were documented and radiographs were evaluated. Results. 61 knees (58 patients) underwent grafting. Three cases were lost to follow-up. In the remaining 58 cases the average age was 40 (range 18–59). At a mean follow-up of 28 months (range 24–36), there were 5 failures requiring further surgery. Mean KOOS scores in the Pain, Symptoms, ADL, Sports, and Quality of Life dimensions were 82, 79, 84, 66, and 58, respectively. Radiographs demonstrated maintenance of the subchondral bone without graft absorption or subsidence. Conclusions. Our observations suggest that osteochondral allograft transplantation leads to a satisfactory activity level and function at early follow-up while avoiding the inherent complexities associated with other cartilage restoration techniques. Longer follow-up is warranted to monitor the subchondral bone, articular surface, and patient outcome measures.

Cell-based chondral restoration

As our patients become more physically active at all ages, the incidence of injuries to articular cartilage is increasing and is causing patients significant pain and disability at a younger age. The intrinsic healing response of articular cartilage is poor, because of its limited vascular supply and capacity for chondrocyte division. Nonsurgical management for the focal cartilage lesion is successful in the majority of patients. Those patients that fail conservative management may be candidates for a cartilage reparative or reconstructive procedure. The type of treatment available depends on a multitude of lesion-specific and patient-specific variables. First-line therapies for isolated cartilage lesions have demonstrated good clinical results in the correct patient but typically repair cartilage with fibrocartilage, which has inferior stiffness, inferior resilience, and poorer wear characteristics. Advances in cell-based cartilage restoration have provided the surgeon a means to address focal cartilage lesions utilizing mesenchymal stem cells, chondrocytes, and biomimetic scaffolds to restore hyaline cartilage.

Cost-effectiveness analyses in orthopaedic sports medicine: a systematic review

BACKGROUND

As increasing attention is paid to the cost of health care delivered in the United States (US), cost-effectiveness analyses (CEAs) are gaining in popularity. Reviews of the CEA literature have been performed in other areas of medicine, including some subspecialties within orthopaedics. Demonstrating the value of medical procedures is of utmost importance, yet very little is known about the overall quality and findings of CEAs in sports medicine.

PURPOSE

To identify and summarize CEA studies in orthopaedic sports medicine and to grade the quality of the available literature.

STUDY DESIGN

Systematic review.

METHODS

A systematic review of the literature was performed to compile findings and grade the methodological quality of US-based CEA studies in sports medicine. The Quality of Health Economic Studies (QHES) instrument and the checklist by the US Panel on Cost-effectiveness in Health and Medicine were used to assess study quality. One-sided Fisher exact testing was performed to analyze the predictors of high-quality CEAs.

RESULTS

Twelve studies met inclusion criteria. Five studies examined anterior cruciate ligament reconstruction, 3 studies examined rotator cuff repair, 2 examined autologous chondrocyte implantation, 1 study examined hip arthroscopic surgery, and 1 study examined the operative management of shoulder dislocations. Based on study findings, operative intervention in sports medicine is highly cost-effective. The quality of published evidence is good, with a mean quality score of 81.8 (range, 70-94). There is a trend toward higher quality in more recent publications. No significant predictor of high-quality evidence was found.

CONCLUSION

The CEA literature in sports medicine is good; however, there is a paucity of studies, and the available evidence is focused on a few procedures. More work needs to be conducted to quantify the cost-effectiveness of different techniques and procedures within sports medicine. The QHES tool may be useful for the evaluation of future CEAs.

Current concepts of articular cartilage restoration techniques in the knee

Context:

Articular cartilage injuries are common in patients presenting to surgeons with primary complaints of knee pain or mechanical symptoms. Treatment options include comprehensive nonoperative management, palliative surgery, joint preservation operations, and arthroplasty.

Evidence Acquisition:

A MEDLINE search on articular cartilage restoration techniques of the knee was conducted to identify outcome studies published from 1993 to 2013. Special emphasis was given to Level 1 and 2 published studies.

Study Design:

Clinical review.

Level of Evidence:

Level 3.

Results:

Current surgical options with documented outcomes in treating chondral injuries in the knee include the following: microfracture, osteochondral autograft transfer, osteochondral allograft transplant, and autologous chondrocyte transplantation. Generally, results are favorable regarding patient satisfaction and return to sport when proper treatment algorithms and surgical techniques are followed, with 52% to 96% of patients demonstrating good to excellent clinical outcomes and 66% to 91% returning to sport at preinjury levels.

Conclusion:

Clinical, functional, and radiographic outcomes may be improved in the majority of patients with articular cartilage restoration surgery; however, some patients may not fully return to their preinjury activity levels postoperatively. In active and athletic patient populations, biological techniques that restore the articular surface may be options that provide symptom relief and return patients to their prior levels of function.

Clinical profiling in cartilage regeneration: prognostic factors for midterm results of matrix-assisted autologous chondrocyte transplantation

BACKGROUND

Matrix-assisted autologous chondrocyte transplantation (MACT) was developed to overcome the limitations of first-generation autologous chondrocyte implantation. Although short-term/midterm results are now available for a small series of patients, the literature still lacks studies on large cohorts of patients evaluated at midterm/long-term follow-up.

PURPOSE

Not all patients can have the same benefit from this procedure. The aim of this study is to analyze a large cohort of patients treated with hyaluronan-based MACT to perform clinical profiling and to highlight the patient- and lesion-specific aspects that play a key role in determining the prognosis.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 142 patients were treated for lesions involving the femoral condyles and trochleae; 133 knees were followed up yearly for 7 years. The average size of the defects was 2.3 ± 1.0 cm2. The origin was traumatic in 44 cases and degenerative in 57 cases, and 32 knees were affected by osteochondritis dissecans (OCD). The clinical outcome was analyzed using the International Knee Documentation Committee (IKDC), EuroQol visual analog scale, and Tegner scores. The influence of the following factors was analyzed: sex, age, body mass index, site, lesion origin, lesion size, previous or combined surgery, and symptom duration.

RESULTS

A marked improvement in all scores was found: the IKDC subjective score increased from the basal level of 39.6 ± 14.4 to 71.9 ± 19.8 (P < .0005) at 12 months; a further improvement was observed at 24 months (77.0 ± 20.5; P < .0005). The results were stable over time up to the 7-year evaluation (77.4 ± 22.1). The failure rate was 10.7%. Better results were seen in the trochleae, and among femoral condyles, the following factors were found to influence the clinical outcome positively: traumatic and OCD origin, male sex, short symptom duration (for traumatic lesions), small lesion size (for OCD), young age, and no previous surgery.

CONCLUSION

Treatment with MACT provides good and stable clinical results. Injury origin, sex, symptom duration, lesion size, lesion site, age, and previous surgery might determine the final outcome and can be used as a sort of clinical profiling to guide the surgeon in the choice of this procedure and in giving realistic expectations to patients requiring cartilage treatment.

Evidence-based status of osteochondral cylinder transfer techniques: a systematic review of level I and II studies

PURPOSE

Our purpose was to examine the Level I and II evidence for the use of osteochondral cylinder transfer technique (OCT) for cartilage repair.

METHODS

A literature search was carried out for Level I and II evidence studies on cartilage repair using the PubMed database. All the studies that involved OCT were identified. Only Level I and II studies that compared OCT to other modalities of treatment such as microfracture (MF) and autologous chondrocyte implantation (ACI) were selected.

RESULTS

A total of 8 studies matched the selection criteria with 2 Level I and 6 Level II studies. Four studies compared OCT with MF, 3 compared OCT with ACI, and one compared all 3 techniques. Of 3 studies, 4 came from a single center. Mean age of patients ranged from 24 to 33 years, and mean follow-up ranged from 9 to 124 months. The studies from the single center showed superior results from OCT over MF, especially in younger patients, with one study having long-term follow-up of 10 years. They also showed an earlier return to sports. The size of the lesions were small (average < 3 cm(2)). The 4 other independent studies did not show any difference between OCT and ACI, with one study showing inferior outcome in the OCT group. Magnetic resonance imaging (MRI) showed good osseous integration of the osteochondral plugs to the subchondral bone. Histologic examination showed that there was hyaline cartilage in the transplanted osteochondral plugs but no hyaline cartilage between the plugs.

CONCLUSIONS

From the studies of a single center, OCT had an advantage over MF in younger patients with small chondral lesions. Comparison of outcomes between OCT and ACI showed no significant difference in 2 studies and contrasting results in another 2 studies. There was insufficient evidence for long-term results for OCT.

LEVEL OF EVIDENCE

Level II, systematic review of Level I and II studies.

A histological comparison of the repair tissue formed when using either Chondrogide(®) or periosteum during autologous chondrocyte implantation

OBJECTIVE

In this study, we compare the clinical and histological outcome between periosteum and Chondrogide(®) during autologous chondrocyte implantation (ACI).

METHOD

This study consisted of 88 patients having received ACI in the knee; 33 treated with Chondrogide(®) (ACI-C) and 55 with periosteum (ACI-P). Post-operative biopsies were taken at a mean of 16.6 ± 8 months (range 7-37 months) and 19 ± 18.4 months (range 4-114) for ACI-C and ACI-P respectively. Histological assessment was performed using the ICRS II and OsScore scoring systems. The immunolocalisation of elastin and collagen types I and II was analysed using specific antibodies. Lysholm scores, a measure of knee function, were obtained pre- and post-operatively at the time of biopsy and annually thereafter.

RESULTS

Compared with ACI-P, the repair tissue formed from patients treated with ACI-C demonstrated a significantly higher score for cellular morphology (ICRS II score), significantly better surface morphology from medial femoral condyle treated defects (ICRS II score) and a significantly higher proportion of hyaline cartilage formation (OsScore). Elastin fibres were present in both ACI-C and ACI-P samples, although their presence was very variable in quantity, distribution, orientation, thickness and length. Patients treated with ACI-C demonstrated significantly more collagen type II immunolocalisation compared with ACI-P. Both groups exhibited a significant increase in Lysholm score post-ACI.

CONCLUSIONS

This study demonstrates a significantly better quality of repair tissue formed with ACI-C compared with ACI-P. Hence Chondrogide(®) is perhaps a better alternative to periosteum during ACI.

Evidence-based status of second- and third-generation autologous chondrocyte implantation over first generation: a systematic review of level I and II studies

PURPOSE

The purpose of this study was to examine the Level I and II evidence for newer generations of autologous chondrocyte implantation (ACI) versus first-generation ACI and to establish whether the newer generations have overcome the limitations associated with first-generation ACI.

METHODS

A literature search was carried out for Level I and II evidence studies on cartilage repair using the PubMed database. All the studies that dealt with ACI were identified. Only Level I and II studies that compared newer generations against earlier generations were selected, whereas studies that compared ACI against other methods of cartilage repair were excluded.

RESULTS

A total of 7 studies matched the selection criteria. Two studies compared periosteum-based autologous chondrocyte implantation (P-ACI) against collagen membrane-based autologous chondrocyte implantation (C-ACI), whereas one study each compared membrane-associated autologous chondrocyte implantation (MACI) against P-ACI and C-ACI. One study on C-ACI compared results related to age, whereas 2 studies evaluated postoperative rehabilitation after MACI. There was weak evidence showing that C-ACI is better than P-ACI and that MACI is comparable with both P-ACI and C-ACI. The weak evidence is because of studies with short durations of follow-up, small numbers of patients, medium-sized defects, and younger age groups. There is good evidence favoring an accelerated weight-bearing regimen after MACI. There is currently no evidence that supports scaffold-based ACI or arthroscopic implantation over first-generation ACI.

CONCLUSIONS

The hypothesis is thus partly proved in favor of C-ACI/MACI against P-ACI with weak evidence, in favor of accelerated weight bearing after MACI with strong evidence, and not in favor of arthroscopic and scaffold-based implantations because of unavailable evidence. LEVEL OF EVIDENCE: Level II, systematic review of Level I and II studies.

Evidence-based status of microfracture technique: a systematic review of level I and II studies

PURPOSE

Although many newer cartilage repair techniques have evolved over the past 2 decades, microfracture is still being advocated as the first line of treatment. Therefore it is timely to conduct a comprehensive review of the literature to assess and report on the current status of Level I and II evidence studies related to microfracture techniques.

METHODS

A literature search was carried out for Level I and II evidence studies on cartilage repair using the PubMed database. All the studies that dealt with microfracture techniques were selected.

RESULTS

Fifteen studies that involved microfracture techniques met the inclusion criteria of this review article, with 6 long-term and 9 short-term studies. These studies compared the clinical outcomes of microfracture with those of other treatments such as autologous chondrocyte implantation and osteochondral cylinder transfers. The majority of the studies reported poor clinical outcomes, whereas 2 studies reported the absence of any significant difference in the results. Small-sized lesions and younger patients showed good results in the short-term. However, osteoarthritis and treatment failures were observed at later postoperative periods of 5 to 10 years.

CONCLUSIONS

The use of microfracture for the treatment of small lesions in patients with low postoperative demands was observed to result in good clinical outcomes at short-term follow-up. Beyond 5 years postoperatively, treatment failure after microfracture could be expected regardless of lesion size. Younger patients showed better clinical outcomes.

LEVEL OF EVIDENCE

Level II, systematic review of Level I and II studies.