Novel Treatment Options for Knee Cartilage Defects in 2023.

Articular cartilage lesions are a common injury that have become increasingly treatable with joint preservation procedures. Well-documented allograft and cellular treatments for these lesions are detailed elsewhere in this volume. This article discusses three new unique options for addressing these defects taking three different paths to address these complex injuries. Agili-C is an existing FDA- and EMEA-approved option using an acellular aragonite-based scaffold to treat both chondral and osteochondral lesions, with or without concurrent arthritis. Cartistem is a stem-cell-based product composed of culture-expanded allogeneic human umbilical cord blood-derived mesenchymal stem cells and hyaluronic acid hydrogel, which is in its final clinical trial stages in the United States, but already has regulatory approval in Korea. IMPACT and RECLAIM studies have shown the safety and efficacy of a new one-stage procedure utilizing autologous chondrons combined with allogeneic mesenchymal stem cells (MSCs) that can provide another effective single-stage treatment option.

Treatment of Shoulder Cartilage Defects in Athletes.

Articular cartilage defects in the glenohumeral joint may be found in laborers, the elderly, and young athletes, among others. Various factors can contribute to cartilage damage, including prior surgery, trauma, avascular necrosis, inflammatory arthritis, joint instability, and osteoarthritis. There is a wide variety of treatment options, from conservative treatment, injections, and surgical options, including arthroscopic debridement, microfracture, osteochondral autograft transfer, osteochondral graft transplantation, autologous chondrocyte implantation, and the newly emerging techniques such as biologic augmentation. There is a challenge to determine the optimal treatment options, especially for young athletes, due to limited outcomes in the literature. However, there are many options which are viable to address osteochondral defects of the glenohumeral joint.

Matrix-Induced Autologous Chondrocyte Implantation Versus Autologous Chondrocyte Implantation of the Knee A Retrospective Comparison.

OBJECTIVE: The purpose of this study was to compare the short-term clinical outcomes of matrix-induced autologous chondrocyte implantation (MACI) to those seen following traditional autologous chondrocyte implantation (ACI) in the management of symptomatic cartilage lesions of the knee. METHODS: This was a retrospective cohort study of patients who underwent either ACI or MACI from January 2011 to March 2018. Patients with a minimum postoperative follow-up of 18 months were contacted. Demographic information, intraoperative findings, and patient-reported functional outcomes scores were collected. Comparisons were made between the two cell-based cartilage repair techniques. RESULTS: Fifty-six patients were included in the study (39 ACI, 17 MACI). Visual analog scale (VAS) for pain scores improved significantly in both groups, with MACI patients demonstrating significantly lower postoperative pain scores compared to those treated with ACI. In the ACI group, there was a decrease in the Tegner Activity score compared to the preoperative baseline, while no significant difference was seen between pre- and postoperative activity levels in the MACI group. Patients were generally satisfied with the outcome of their procedures, and there was no significant difference in satisfaction between groups. No patients re-quired additional surgery during the follow-up period. CONCLUSION: Both ACI and MACI demonstrated good short-term postoperative clinical results with improved pain and activity levels compared to the preoperative baseline. Patients treated with the MACI technique demonstrated greater reductions in pain scores compared to ACI, and while ACI resulted in a decrease in levels of postoperative activity, activity levels for MACI remained stable.

Rates and predictors of reimplantation of matrix-induced autologous chondrocyte implantation following first stage cartilage harvest: A cohort study.

PURPOSE: To assess the reimplantation rate and predictors of patients requiring second-staged matrix-induced autologous chondrocyte implantation (MACI) reimplantation after initial first stage cartilage biopsy. METHODS: A retrospective review was performed from 2018 to 2022 among patients who underwent only phase I MACI biopsy procedure (biopsy group) or both phase I with transition to phase II implantation of chondrocytes (implantation group) at a single tertiary center. Demographic, qualitative, and quantitative measurements were recorded, and univariate and multivariate regression analysis was performed to assess predictors of ultimately requiring second stage MACI implantation. RESULTS: A total of 71 patients (51% female, age 27.7 ± 10.6 years (range 12-50)) were included in this study. Eventually, 25 of 71 patients (35.2%) experienced persistence of symptoms after initial MACI biopsy and other concomitant procedures, requiring second-stage implantation. Univariate analysis showed the implantation group compared to the biopsy group had a greater lesion size (5.2 cm2 ± 3.3 vs. 3.3 cm2 ± 1.4, p = 0.024), a higher proportion patients ≥ 26 years of age (76% vs. 43%, p = 0.009), a medial femoral condyle lesion more commonly (33% vs 11%, p = 0.005), were more often female (72% vs. 39%, p = 0.008), and had less often soft tissue repair at time of biopsy (32% vs. 61%, p = 0.020). Backward multivariate logistic regression analysis revealed that size of the lesion (OR 1.43, p = 0.031) and age ≥ 26 years old at time of biopsy (OR 3.55, p = 0.042) were independent predictors of not responding to initial surgery and requiring implantation surgery. CONCLUSION: This study found that 35% of patients undergoing MACI phase I biopsy harvest eventually required autologous implantation. Independent risk factors for progressing to implantation after failed initial surgery were larger defect size and older age. LEVEL OF EVIDENCE: III, Cohort Study.

Injectable Cartilage Microtissue Regenerated by Autologous Chondrocytes for Nasal Augmentation: A 5-Year Follow-Up Study.

BACKGROUND: A lack of ideal filling materials is a critical limitation in current rhinoplasty. Cartilage sheet regeneration by autologous chondrocytes is expected to provide an ideal source of material. However, the inability to perform minimally invasive transplantation of cartilage sheets has greatly limited the clinical application of this material. In this article, the authors propose the concept of injectable cartilage microtissue (ICM) based on cartilage sheet technology, with the aim of achieving minimally invasive augmentation rhinoplasty in clinical practice. METHODS: Approximately 1.0 cm2 of posterior auricular cartilage was collected from 28 patients. Isolated chondrocytes were expanded, then used to construct autologous cartilage sheets by high-density seeding and in vitro culture in chondrogenic medium with cytokines (eg, transforming growth factor beta-1 and insulin-like growth factor-1) for 3 weeks. Next, ICM was prepared by granulation of the cartilage sheets; it was then injected into a subcutaneous pocket for rhinoplasty. RESULTS: ICM was successfully prepared in all patients, and its implantation efficiently raised the nasal dorsum. Magnetic resonance imaging confirmed that regenerative tissue was present at the injection site; histologic examinations demonstrated mature cartilage formation with typical cartilage lacunae and abundant cartilage-specific deposition of extracellular matrix. Excellent or good postoperative patient satisfaction results were achieved in 83.3% of patients over 5 years of follow-up. Obvious absorption of grafts occurred in only two patients (8.3%). CONCLUSIONS: These results demonstrated that ICM could facilitate stable cartilage regeneration and long-term maintenance in the human body; the implantation of ICM enabled natural augmentation of the depressed nasal dorsum. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

An injectable active hydrogel based on BMSC-derived extracellular matrix for cartilage regeneration enhancement.

Articular cartilage injury impairs joint function and necessitates orthopedic intervention to restore the structure and function of the cartilage. Extracellular matrix (ECM) scaffolds derived from bone marrow mesenchymal stem cells (BMSCs) can effectively promote cell adhesion, proliferation, and chondrogenesis. However, pre-shaped ECM scaffolds have limited applicability due to their poor fit with the irregular surface of most articular cartilage defects. In this study, we fabricated an injectable active ECM hydrogel from autologous BMSCs-derived ECM by freeze-drying, liquid nitrogen milling, and enzymatic digestion. Moreover, our in vitro and in vivo results demonstrated that the prepared hydrogel enhanced chondrocyte adhesion and proliferation, chondrogenesis, cartilage regeneration, and integration with host tissue, respectively. These findings indicate that active ECM components can provide trophic support for cell proliferation and differentiation, restoring the structure and function of damaged cartilage.

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.

Fresh Osteochondral Allograft for Large Talar Osteochondral Lesions.

Osteochondral lesions of the talus are being recognized as an increasingly common injury. Large osteochondral lesions have significant biomechanical consequences and often require resurfacing with both boney and cartilaginous graft. The current treatment options include osteochondral autograft transfer, mosaicplasty, autologous chondrocyte implantation, or osteochondral allograft transplantation. Allograft procedures have the advantage of no donor site morbidity and ability to match the defect line to line. Careful transportation, storage, and handling of the allograft are critical to success. The failure of nonoperative management, failure of arthroscopic treatment, or large defects are an indication for resurfacing.

Bioengineering autologous cartilage grafts for functional posterior lamellar eyelid reconstruction: A preliminary study in rabbits.

The reconstruction of posterior lamellar eyelid defects remains a significant challenge in clinical practice due to anatomical complexity, specialized function, and aesthetic concerns. The ideal substitute for the posterior lamellar should replicate the native tarsoconjunctival tissue, providing both mechanical support for the eyelids and a smooth surface for the globe after implantation. In this study, we present an innovative approach utilizing tissue-engineered cartilage (TEC) grafts generated from rabbit auricular chondrocytes and a commercialized type I collagen sponge to reconstruct critical-sized posterior lamellar defects in rabbits. The TEC grafts demonstrated remarkable mechanical strength and maintained a stable cartilaginous phenotype both in vitro and at 6 months post-implantation in immunodeficient mice. When employed as autografts to reconstruct tarsal plate defects in rabbits' upper eyelids, these TEC grafts successfully restored normal eyelid morphology, facilitated smooth eyelid movement, and preserved the histological structure of the conjunctival epithelium. When applied in bilayered tarsoconjunctival defect reconstruction, these TEC grafts not only maintained the normal contour of the upper eyelid but also supported conjunctival epithelial cell migration and growth from the defect margin towards the centre. These findings highlight that auricular chondrocyte-based TEC grafts hold great promise as potential candidates for clinical posterior lamellar reconstruction. STATEMENT OF SIGNIFICANCE: The complex structure and function of the posterior lamellar eyelid continue to be significant challenges for clinical reconstructive surgeries. In this study, we utilized autologous auricular chondrocyte-based TEC grafts for posterior lamellar eyelid reconstruction in a preclinical rabbit model. The TEC grafts exhibited native cartilaginous histomorphology and comparable mechanical strength to those of the native human tarsal plate. In rabbit models with either tarsal plate defects alone or bilayered tarsoconjunctival defects, TEC grafts successfully restored the normal eyelid contour and movement, as well as supported preservation and growth of conjunctival epithelium. This is the first study to demonstrate autologous TEC grafts can be employed for repairing tarsal plate defects, thereby offering an alternative therapeutic approach for treating posterior lamellar defects in clinic settings.

Ex vivo storage of human osteochondral allografts: Long-term analysis over 300 days using a Ringer-based solution.

Large osteochondral defects are a major challenge in orthopedics, for which osteochondral allograft (OCA) transplantation is nowadays considered as an option, especially in young patients. However, a major issue with OCA is the need for graft storage, which ensures adequate cartilage integrity over time. The aim of this study was to test how long a Ringer-based storage solution can provide good graft quality after explantation and thus meet the requirements for OCA. For this purpose, human osteochondral allografts of the knee and ankle were analyzed. Live/Dead analysis was performed and glycosaminoglycan, as well as hydroxyproline content, were measured as crucial chondrocyte integrity factors. Furthermore, biomechanical tests focusing on stress relaxation and elastic compression modulus were performed. The critical value of 70% living chondrocytes, which corresponds to a number of 300 cells/mm², was reached after an average of 16 weeks of storage. In addition, a constant cell shrinkage was observed over time. The amount of glycosaminoglycan and hydroxyroline showed a slight and constant decrease over time, but no significant differences when compared from Day 0 to the values at Weeks 40-43. Biomechanical testing also revealed no significant differences at the different time points. Therefore, the results show that the Ringer-based storage solution at 4°C is able to provide a chondrocyte survival of 70% until Week 16. This is comparable to previously published storage solutions. Therefore, the study contributes to the establishment of a Ringer-based osteochondral allograft transplantation system for countries where medium-based storage solution cannot be approved.

The role of autologous bone grafting in matrix-associated autologous chondrocyte implantation at the knee: Results from the German Cartilage Registry (KnorpelRegister DGOU).

PURPOSE: To investigate whether concomitant autologous bone grafting adversely affects clinical outcome and graft survival after matrix-associated autologous chondrocyte implantation (M-ACI). METHODS: The present study examines registry data of patients who underwent M-ACI with or without autologous bone grafting for large-sized chondral or osteochondral defects. Propensity score matching was performed to exclude potential confounders. A total of 215 patients with similar baseline characteristics were identified. Clinical outcome was assessed at the time of surgery and at 6, 12, 24, 36 and 60 months using the Knee Injury and Osteoarthritis Outcome Score (KOOS). KOOS change, clinical response rate, KOOS subcomponents and failure rate were determined. RESULTS: Patients treated with M-ACI and autologous bone grafting achieved comparable clinical outcomes compared with M-ACI alone. At 24 months postoperatively, the patient-reported outcome (PRO) of patients treated with M-ACI and autologous bone grafting was even significantly better as measured by KOOS (74.9 ± 18.8 vs. 79.2 ± 15.4; p = 0.043). However, the difference did not exceed the minimal clinically important difference (MCID). In patients with M-ACI and autologous bone grafting, a greater change in KOOS relative to baseline was observed at 6 (9.3 ± 14.7 vs. 15.0 ± 14.7; p = 0.004) and 12 months (12.6 ± 17.2 vs. 17.7 ± 14.6; p = 0.035). Overall, a high clinical response rate was observed in both groups at 24 months (75.8% vs. 82.0%; p = n.s.). The estimated survival at the endpoint of reoperation for any reason was 82.1% (SD 2.8) at 8.4 years for isolated M-ACI and 88.7% (SD 2.4) at 8.2 years for M-ACI with autologous bone grafting (p = 0.039). CONCLUSIONS: Even in the challenging cohort of large osteochondral defects, the additional treatment with autologous bone grafting leads to remarkably good clinical outcomes in patients treated with M-ACI. In fact, they tend to benefit more from surgery, have lower revision rates and achieve clinical response rates earlier. Subchondral bone management is critical to the success of M-ACI and should be addressed in the treatment of borderline defects. LEVEL OF EVIDENCE: Level III.

Total meniscus replacement with a 3D printing of network hydrogel composite scaffold in a rabbit model.

PURPOSE: The aim of this study was to evaluate the role of a novel total meniscal implant in promoting meniscal regeneration and protecting articular cartilage in a rabbit model for 3 and 6 months. METHODS: Thirty-six New Zealand rabbits were selected and divided into poly(ɛ-caprolactone) (PG-Pg) scaffold group, meniscectomy group and sham group. In this study, it was investigated whether PG-Pg scaffold can prevent articular cartilage degeneration and promote tissue degeneration, and its mechanical properties at 3 and 6 months after surgery were also explored. RESULT: The degree of articular cartilage degeneration was significantly lower in the PG-Pg scaffold group than in the meniscectomy group. The number of chondrocytes increased in the PG-Pg scaffold at 3 and 6 months, while a gradual increase in the mechanical properties of the PG-Pg stent was observed from 6 months. CONCLUSION: The PG-Pg scaffold slows down the degeneration of articular cartilage, promotes tissue regeneration and improves biomechanical properties after meniscectomy. This novel meniscus scaffold holds promise for enhancing surgical strategies and delivering superior long-term results for individuals with severe meniscus tears. LEVEL OF EVIDENCE: NA.

10-Year Prospective Clinical and Radiological Evaluation After Matrix-Induced Autologous Chondrocyte Implantation and Comparison of Tibiofemoral and Patellofemoral Graft Outcomes.

BACKGROUND: Long-term outcomes in larger cohorts after matrix-induced autologous chondrocyte implantation (MACI) are required. Furthermore, little is known about the longer-term clinical and radiological outcomes of MACI performed in the tibiofemoral versus patellofemoral knee joint. PURPOSE: To present the 10-year clinical and radiological outcomes in patients after MACI and compare outcomes in patients undergoing tibiofemoral versus patellofemoral MACI. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Between September 2002 and December 2012, 204 patients who underwent MACI were prospectively registered into a research program and assessed preoperatively and at 2, 5, and 10 years postoperatively. Of these patients, 168 were available for clinical review at 10 years, with 151 (of a total of 182) grafts also assessed via magnetic resonance imaging (MRI). Patients were evaluated using the Knee injury and Osteoarthritis Outcome Score, a visual analog scale for pain frequency and severity, satisfaction, and peak isokinetic knee extensor and flexor strength. Limb symmetry indices (LSIs) were calculated for strength measures. Grafts were scored on MRI scans via the MOCART (magnetic resonance observation of cartilage repair tissue) system, with a focus on tissue infill and an overall MRI graft composite score. RESULTS: All patient-reported outcome measures improved (P < .0001) up to 2 years after surgery. Apart from the significant increase (P = .004) in the peak isokinetic knee extensor LSI, no other patient-reported outcome measure or clinical score had changed significantly from 2 to 10 years. At the final follow-up, 92% of patients were satisfied with MACI to provide knee pain relief, with 76% satisfied with their ability to participate in sports. From 2 to 10 years, no significant change was seen for any MRI-based MOCART variable nor the overall MRI composite score. Of the 151 grafts reviewed via MRI at 10 years, 14 (9.3%) had failed, defined by graft delamination or no graft tissue on MRI scan. Furthermore, of the 36 patients (of the prospectively recruited 204) who were not available for longer-term review, 7 had already proceeded to total knee arthroplasty, and 1 patient had undergone secondary MACI at the same medial femoral condylar site because of an earlier graft failure. Therefore, 22 patients (10.8%) essentially had graft failure over the period. At the final follow-up, patients who underwent MACI in the tibiofemoral (vs patellofemoral) joint reported significantly better Knee injury and Osteoarthritis Outcome Score subscale scores for Quality of Life (P = .010) and Sport and Recreation (P < .001), as well as a greater knee extensor strength LSI (P = .002). Even though the tibiofemoral group demonstrated better 10-year MOCART scores for tissue infill (P = .027), there were no other MRI-based differences (P > .05). CONCLUSION: This study reports the long-term review of a prospective series of patients undergoing MACI, demonstrating good clinical scores, high levels of patient satisfaction, and acceptable graft survivorship at 10 years. Patients undergoing tibiofemoral (vs patellofemoral) MACI reported better long-term clinical outcomes, despite largely similar MRI-based outcomes.

MR imaging after patellar MACI and MPFL reconstruction: a comparison of isolated versus combined procedures.

OBJECTIVE: To qualitatively and quantitatively evaluate the 2.5-year MRI outcome after Matrix-associated autologous chondrocyte implantation (MACI) at the patella, reconstruction of the medial patellofemoral ligament (MPFL), and combined procedures. METHODS: In 66 consecutive patients (age 22.8 ± 6.4years) with MACI at the patella (n = 16), MPFL reconstruction (MPFL; n = 31), or combined procedures (n = 19) 3T MRI was performed 2.5 years after surgery. For morphological MRI evaluation WORMS and MOCART scores were obtained. In addition quantitative cartilage T2 and T1rho relaxation times were acquired. Several clinical scores were obtained. Statistical analyses included descriptive statistics, Mann-Whitney-U-tests and Pearson correlations. RESULTS: WORMS scores at follow-up (FU) were significantly worse after combined procedures (8.7 ± 4.9) than after isolated MACI (4.3 ± 3.6, P = 0.005) and after isolated MPFL reconstruction (5.3 ± 5.7, P = 0.004). Bone marrow edema at the patella in the combined group was the only (non-significantly) worsening WORMS parameter from pre- to postoperatively. MOCART scores were significantly worse in the combined group than in the isolated MACI group (57 ± 3 vs 88 ± 9, P < 0.001). Perfect defect filling was achieved in 26% and 69% of cases in the combined and MACI group, respectively (P = 0.031). Global and patellar T2 values were higher in the combined group (Global T2: 34.0 ± 2.8ms) and MACI group (35.5 ± 3.1ms) as compared to the MPFL group (31.1 ± 3.2ms, P < 0.05). T2 values correlated significantly with clinical scores (P < 0.005). Clinical Cincinnati scores were significantly worse in the combined group (P < 0.05). CONCLUSION: After combined surgery with patellar MACI and MPFL reconstruction inferior MRI outcomes were observed than after isolated procedures. Therefore, patients with need for combined surgery may be at particular risk for osteoarthritis.

Osteochondritis Dissecans Lesions of the Knee: Evidence-Based Treatment.

Osteochondritis dissecans (OCD) of the knee is a potentially disabling condition in adolescent and young adults, which is likely multifactorial in origin. In recent years, there have been notable improvements in identification and treatment. Clinical presentation varies based mostly on OCD lesion stability. Patients with stable lesions generally present with vague knee pain and altered gait while mechanical symptoms and effusion are more common with unstable lesions. Lesions most commonly occur on the lateral aspect of the medial femoral condyle in patients aged 10 to 20 years. Magnetic resonance imaging is vital to diagnose and predict clinical treatment, which is largely based on stability of the fragment. Conservative treatment of stable lesions in patients with open physis is recommended with protected weight-bearing and gradual progression of activities over the course of 3 to 6 months. Stable OCD lesions which failed a nonsurgical course can be treated with transarticular or retrograde drilling while unstable lesions usually require fixation, autologous chondrocyte implantation (ACI), osteochondral autograft transfer (OATS), or osteochondral allograft transplantation. This review highlights the most current understanding of knee OCD lesions and treatment options with the goal of optimizing outcomes in this difficult pathology.

Impact of Wiberg Patellar Type on Outcomes and Survival Following Cell-Based Cartilage Repair for Patellar Chondral Lesions at Midterm Follow-up.

BACKGROUND: Cell-based cartilage repair procedures of the patellofemoral joint have less reliable outcomes than those of the tibiofemoral joint. No previous studies have evaluated the influence of patellar shape on cell-based cartilage repair outcomes. Patellar dysplasia may predispose patients to worse outcomes after cell-based cartilage repair. PURPOSE/HYPOTHESIS: The purpose of this study was to evaluate the relationship between Wiberg patellar type and outcomes after cell-based cartilage repair (autologous chondrocyte implantation or particulated juvenile allograft cartilage transplantation) for the treatment of patellar chondral lesions at a minimum 2-year follow-up. It was hypothesized that Wiberg classification of patellar shape would have no effect on patient-reported outcome measures (PROMs) or graft survival. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Patients undergoing autologous chondrocyte implantation or particulated juvenile allograft cartilage transplantation for full-thickness patellar chondral defects between 2016 and 2020 were retrospectively reviewed after institutional review board approval. The change in PROMs, including International Knee Documentation Committee (IKDC), Kujala, and Veterans RAND 12-item Health Survey Mental and Physical scores, from pre- to postoperatively and the percentage of patients who achieved the minimal clinically important difference (MCID) for IKDC and Kujala scores were compared for the Wiberg type A versus Wiberg type B versus Wiberg type C groups. The log-rank test was used to evaluate for differences in survival between subgroups. RESULTS: A total of 59 patients (63 knees) were included, with a mean age of 33.3 ± 8.6 years, median body mass index of 26.0 (IQR, 21.8-30.2), and median follow-up time of 3.5 years (IQR, 2.6-4.2 years). In total, 26 (41%) patellae were Wiberg type A, 29 (46%) were Wiberg type B, and 8 (13%) were Wiberg type C. There were no differences between Wiberg type A versus Wiberg type B versus Wiberg type C groups with respect to change in PROMs from pre- to postoperatively or the percentage of patients who achieved the MCID for IKDC or Kujala scores (P > .05 for all). There were no differences in survival between groups (P = .45). CONCLUSION: Wiberg patellar type has no effect on patient-reported outcomes or graft survival at midterm follow-up. Patellar dysplasia should not be seen as a contraindication for cell-based cartilage repair procedures.

Autologous Costal Chondral/Osteochondral Transplantation and Costa-Derived Chondrocyte Implantation for Articular Cartilage Repair: Basic Science and Clinical Applications.

There has been increasing application of autologous costal chondral/osteochondral transplantation (ACCT/ACOT) and costa-derived chondrocyte implantation (ACCI) for articular cartilage repair over the past three decades. This review presents the major evidence on the properties of costal cartilage and bone and their qualifications as grafts for articular cartilage repair, the major clinical applications, and the risks and strategies for costal chondral/osteochondral graft(s) harvest. First, costal cartilage has many specific properties that help restore the articular surface. Costa, which can provide abundant cartilage and cylindrical corticocancellous bone, preserves permanent chondrocyte and is the largest source of hyaline cartilage. Second, in the past three decades, autologous costal cartilage-derived grafts, including cartilage, osteochondral graft(s), and chondrocyte, have expanded their indications in trauma and orthopaedic therapy from small to large joints, from the upper to lower limbs, and from non-weight-bearing to weight-bearing joints. Third, the rate of donor-site complications of ACCT or ACOT is low, acceptable, and controllable, and some skills and accumulated experience can help reduce the risks of ACCT and ACOT. Costal cartilage-derived autografting is a promising technique and could be an ideal option for articular chondral lesions with or without subchondral cysts. More high-quality clinical studies are urgently needed to help us further understand the clinical value of such technologies.

Significant improvements in clinical outcome measures and patient satisfaction after combined all-arthroscopic meniscal allograft transplantation and autologous chondrocyte implantation: A single-centre longitudinal study.

PURPOSE: The optimal treatment approach for the complex pathology of meniscal insufficiency and coexisting full-thickness cartilage defects remains unclear. The purpose of this study was to evaluate the viability, safety, and efficacy of this combined surgical approach at medium-term follow-up. METHODS: This is a single-centre longitudinal study with blinded outcome assessment. All consecutive patients treated with combined all-arthroscopic meniscal allograft transplantation (MAT) with bone bridge fixation and ACI using chondrospheres at our institution between 2001 and 2021 were eligible for inclusion. Twenty patients with an average follow-up of 72.6 ± 34.4 months were included in the statistical analysis. Clinical outcomes were assessed pre- and postoperatively using the IKDC Subjective Knee Form, Lysholm Score, Tegner Activity Scale, KOOS, and Visual Analog Scale (VAS) for patient satisfaction. Failure and reoperation rates were assessed, and cartilage regeneration tissue was evaluated on postoperative MRI. RESULTS: IKDC scores significantly improved from 52.1 ± 16.9 to 68.5 ± 16.3 (p = 0.003). Lysholm scores improved from 61.5 ± 21.7 to 78.5 ± 12.9 (p = 0.004). Tegner scores improved from 3.5 (1-4) to 4.0 (2-6) (p = 0.014). KOOS scores improved significantly across all subcategories, except 'symptoms', where improvements did not reach statistical significance. VAS for overall patient satisfaction showed improvements but did not reach statistical significance. The combined procedure was successful in 17 patients (85%). Eight patients had to undergo reoperation (40%), comprising mostly small, arthroscopic procedures. Seven reoperations were directly attributable to meniscal allograft transplantation (46.7%). Postoperative Magnetic Resonance Observation of Cartilage Repair Tissue scores were 68.9 ± 16.8 (n = 14). CONCLUSION: Combined arthroscopic MAT and autologous chondrocyte implantation (ACI) is a viable, safe, and effective treatment approach for younger patients with meniscal insufficiency and coexisting full-thickness cartilage damage, where alternative treatment options are limited. The combined surgical procedure achieved significant improvements in clinical outcome measures and patient satisfaction with acceptable failure and high arthroscopic reoperation rates. MAT is the limiting part of this combined procedure, with most failures and reoperations being attributable to MAT, as opposed to ACI. LEVEL OF EVIDENCE: Level III.

Costal Chondrocyte-Derived Pellet-Type Autologous Chondrocyte Implantation Versus Microfracture for the Treatment of Articular Cartilage Defects: A 5-Year Follow-up of a Prospective Randomized Trial.

BACKGROUND: Costal chondrocyte-derived pellet-type autologous chondrocyte implantation (CCP-ACI) has been introduced as a new therapeutic option for the treatment of articular cartilage defects. We had previously conducted a randomized controlled trial comparing CCP-ACI versus microfracture at 1 year postoperatively. PURPOSE: To compare the efficacy and safety of CCP-ACI versus microfracture for the treatment of articular cartilage defects of the knee at 5 years postoperatively. STUDY DESIGN: Randomized controlled trial; Level of evidence, 2. METHODS: This study describes the mean 5-year follow-up of a previously published prospective clinical trial. The previous prospective trial compared the results of CCP-ACI versus microfracture until 1 year of follow-up. Of the 30 patients who were included in the previous study, 25 were followed up for 5 years. Patients were evaluated based on clinical outcome scores (Lysholm score, International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score [KOOS], and visual analog scale for pain), magnetic resonance imaging findings, and rates of treatment failure at last follow-up. RESULTS: The MOCART (Magnetic Resonance Observation of Cartilage Repair Tissue) score in the CCP-ACI group was significantly higher than that in the microfracture group at 5 years (62.3 vs 26.7, respectively; P < .0001). The Lysholm score and KOOS score in the CCP-ACI group were significantly higher than those in the microfracture group at 5 years (84.5 vs 64.9, respectively, and 390.9 vs 303.0, respectively; P = .023 and P = .017, respectively). There was 1 case of treatment failure that occurred in the microfracture group. CONCLUSION: The present randomized controlled trial indicated that the results of both procedures clinically and statistically significantly improved at 1 and 5 years' follow-up in treating cartilage defects, but the results of CCP-ACI were superior to those of microfracture. Magnetic resonance imaging conducted at 1 year and 5 years after CCP-ACI revealed statistically significant superior structural integration with native cartilage tissue compared with microfracture. REGISTRATION: NCT03545269 (ClinicalTrials.gov).