A Cell-Free Collagen Type I Device for the Treatment of Focal Cartilage Defects

The purpose of this study was to evaluate the potential value of a cell-free collagen type I gel plug for the treatment of focal cartilage defects. Cellular migration and proliferation was addressed in vitro, and the formation of repair tissue in a nude mouse-based defect model. A cell-free plug made of collagen type I was placed in the center of an incubation plate. Surrounding space was filled with a collagen type I gel (Arthro Kinetics, Esslingen, Germany) seeded with 2 × 10⁵ human articular chondrocytes/mL gel. After cultivation for up to 6 weeks in vitro, samples were subject to histological and immunohistochemical staining and gene expression analysis. Subsequently, chondral defects of human osteochondral blocks were treated with the plug, and specimens were cultivated subcutaneously in nude mice for 6 weeks. The repair tissue was evaluated macroscopically, and collagen type II production was investigated immunohistochemically. In vitro, morphology of immigrated cells did not show any differences, as did collagen type II gene expression. After 4 weeks, the plug was homogeneously inhabited. After 6 weeks of cultivation in nude mice, collagen gel plug treatment led to a macroscopically excellent repair tissue. Histological staining revealed a tight bonding, and the collagen gel plug started to be remodeled. We conclude that the novel collagen gel plug device offers an environment favorable for the migration of articular chondrocytes and leads to a good-quality repair tissue in the nude mouse model. The arthroscopic transplantation of a collagen gel plug may be one option in the treatment of focal cartilage defects.     

Autologous Chondrocyte Implantation for Talar Osteochondral Lesions: Comparison Between 5-Year Follow-Up Magnetic Resonance Imaging Findings and 7-Year Follow-Up Clinical Results

Autologous chondrocyte implantation (ACI) is an established surgical procedure that has provided satisfactory results. The aim of the present study was to correlate the clinical outcomes of a series of 20 patients treated by ACI at a 7-year follow-up examination with the magnetic resonance imaging (MRI) T2-mapping 5-year follow-up findings. We evaluated 20 patients using the American Orthopaedic Foot and Ankle Society (AOFAS) score preoperatively and the established follow-up protocol until 87.2 ± 14.5 months. MRI T2-mapping sequences were acquired at the 5-year follow-up examination. At the MRI examination (60 ± 12 months), the mean AOFAS score improved from 58.7 ± 15.7 to 83.9 ± 18.4. At the final follow-up examination at 87.2 ± 14.5 months, the AOFAS score was 90.9 ± 12.7 (p = .0005). Those patients who experienced an improvement between 5 and 7 years after surgery had a significant greater percentage of T2-map value of 35 to 45 ms (hyaline cartilage) compared with those patients who did not improve (p = .038). MRI T2 mapping was shown to be a valuable tool capable of predicting reproducible clinical outcomes after ACI even 7 years after surgery. The quality of the regenerated tissue and the degree of defect filling became statistically significant to the clinical results at the final follow-up examination.     

Treatment of a Focal Articular Cartilage Defect of the Talus with Polymer-Based Autologous Chondrocyte Implantation: A 12-Year Follow-Up Period

Autologous chondrocyte implantation (ACI) is a first-line treatment option for large articular cartilage defects. Although well-established for cartilage defects in the knee, studies of the long-term outcomes of matrix-assisted ACI to treat cartilage defects in the ankle are rare. In the present report, we describe for the first time the long-term clinical and radiologic results 12 years after polymer-based matrix-assisted ACI treat a full-thickness talar cartilage defect in a 25-year-old male patient. The clinical outcome was assessed using the visual analog scale and Freiburg ankle score, magnetic resonance imaging evaluation using the Henderson-Kreuz scoring system and T2 mapping. Clinical assessment revealed improved visual analog scale and Freiburg ankle scores. The radiologic analysis and T2 relaxation time values indicated the formation of hyaline-like repair tissue. Polymer-based autologous chondrocytes has been shown to be a safe and clinically effective long-term treatment of articular cartilage defects in the talus.     

Autologous chondrocyte implantation for the treatment of retropatellar cartilage defects: clinical results referred to defect localisation

Introduction  Although autologous chondrocyte implantation (ACI) has become well established for the treatment of full-thickness cartilage defects of the knee joint, nevertheless clinical results of retropatellar lesions are still inferior compared to those of defects located on femoral condyles. We report the clinical results obtained in 70 patients treated with ACI for full-thickness defects of the patella, with special reference to defect location and size, age, body mass index and sports activity. Methods  At a follow-up of 38.4 months (range 14–64, follow-up rate 83.3%), patients’ subjective functional knee scores (IKDC, Lysholm) were analysed, as were the results of objective examination (according to ICRS). Results  Mean patient age at the time of surgery was 34.3 years (±10.1). The mean Lysholm score at the time of follow-up was 73.0 (±22.4) and the subjective IKDC score was 61.6 (±21.5); normal and nearly normal clinical results according to the objective criteria of the International Cartilage Research Society (ICRS) were achieved in 67.1% of the patients, while abnormal results were achieved in 20.0% of the patients and severely abnormal results, in 12.9%. While different surgical techniques did not seem to have any significant influence on the treatment results, both defect size and defect location within the patella were found to be significantly associated with clinical outcome. The corollaries to this are that larger cartilage lesions of the patella are associated with an inferior outcome (p = 0.007) and that cartilage defects located on the lateral patellar facet are correlated with a better clinical outcome than those located on the medial facet or those involving both facets (p = 0.017). Conclusion  This study demonstrates that within a group of patients treated with ACI for retropatellar cartilage lesion there are significant differences in clinical outcome, which are important and should be taken into account of when a decision has to be made on whether or not ACI is indicated.     

Osteochondral Grafting for Treatment of a Massive Chondral Defect in the Knee of a Young Adult With Anterior Cruciate Ligament Deficit

We report the case of a 28-year-old woman who underwent osteochondral grafting and anterior cruciate ligament (ACL) reconstruction for treatment of a massive cartilage defect in a knee joint with ACL deficit. Arthroscopy showed a full-thickness degenerative cartilage defect measuring 22 × 35 mm in the weight-bearing area of the medial femoral condyle, a totally resected lateral meniscus, and a loosened ACL. Therefore we performed osteochondral autograft transplantation and ACL reconstruction. Osteochondral plugs were harvested from a donor site in the patellofemoral joint of the contralateral knee and grafted into the recipient site in a “skipping” manner. Arthroscopic examination 1 year after surgery showed good preservation of the grafts and satisfactory bridging of the gaps between the plugs with fibrocartilage-like tissue. A recent follow-up examination, performed 36 months after surgery, has shown an excellent result, with a Lysholm score of 100, an International Knee Documentation Committee score of 95.4, and full range of knee motion with no symptoms. Plain radiographs at that time showed preservation of the medial joint space on the weighted anteroposterior view. No osteoarthritic changes were evident in the patellofemoral joint.     

Cartilage repair: A review of Stanmore experience in the treatment of osteochondral defects in the knee with various surgical techniques

Articular cartilage damage in the young adult knee, if left untreated, it may proceed to degenerative osteoarthritis and is a serious cause of disability and loss of function. Surgical cartilage repair of an osteochondral defect can give the patient significant relief from symptoms and preserve the functional life of the joint. Several techniques including bone marrow stimulation, cartilage tissue based therapy, cartilage cell seeded therapies and osteotomies have been described in the literature with varying results. Established techniques rely mainly on the formation of fibro-cartilage, which has been shown to degenerate over time due to shear forces. The implantation of autologous cultured chondrocytes into an osteochondral defect, may replace damaged cartilage with hyaline or hyaline-like cartilage. This clinical review assesses current surgical techniques and makes recommendations on the most appropriate method of cartilage repair when managing symptomatic osteochondral defects of the knee. We also discuss the experience with the technique of autologous chondrocyte implantation at our institution over the past 11 years.     

Transplantation of Autologous Chondrocytes Seeded on a Fibrin/Hyaluronan Composite Gel Into Tracheal Cartilage Defects in Rabbits: Preliminary Results

Reconstruction of tracheal defects is one of the most difficult procedures in head and neck surgery. To date, various reconstructing techniques have been used with no consensus on the best approach. This study investigated the feasibility of using a fibrin/hyaluronic acid (HA) composite gel with autologous chondrocytes for tracheal reconstruction. Chondrocytes from autologous rabbit auricular cartilages were expanded and seeded into a culture dish at high density to form stable tracheal cartilages mechanically using a fibrin/HA composite gel. A 1‐cm long by 0.5‐cm wide defect was created by a scalpel on the cervical tracheae of six rabbits. Tissue‐engineered cartilages using fibrin/HA composite were trimmed and fixed to the defect boundaries with tissuecol. Postoperatively, the site was evaluated endoscopically, histologically, radiologically, and functionally. None of the six rabbits showed signs of respiratory distress. Postoperatively, in all cases, rigid telescopic examination showed that the implanted scaffolds were completely covered with regenerated mucosa without granulation or stenosis. Histologically, the grafts showed no signs of inflammatory reaction and were covered with ciliated epithelium. Even when grafts were broken and migrated from their original insertion site, the implanted cartilages were well preserved. However, the grafts did show signs of mechanical failure at the implantation site. The beat frequency of ciliated epithelium on implants was very similar to that of normal respiratory mucosa. In conclusion, implants with autologous chondrocytes cultured with fibrin/HA showed good tracheal luminal contour, functional epithelial regeneration, and preservation of neocartilage without inflammation but lacked adequate mechanical stability.     

Long-term follow-up evaluation of autologous chondrocyte implantation for symptomatic cartilage lesions of the knee: A single-centre prospective study

IntroductionAutologous Chondrocyte Implantation (ACI) has been the first technique in reconstruction of a valid articular surface. The aim of this study was to evaluate clinical results of this technique at an average follow up of 162 ± 27 months (range 88–208) in a group of patients who underwent ACI.Materials and methods32 patients were operated between 1997 and 2007 for chondral lesions or osteochondritis dissecans of the knee. Mean size of the defect was 5.48 cm² ± 1.53 (range 2–9). Nine patients were treated with I generation technique and 23 with II generation. All patients were evaluated with Subjective IKDC and Tegner Activity Scales for clinical outcomes and with EQ-VAS for a quantitative measure of health after intervention, starting from pre-operative period and at regular follow up (minimum 88 months-maximum 208 months).ResultsA significant increment of all scores was noticed comparing preoperative and postoperative results. In particular medium IKDC score increased from 40.3 ± 9.6 in preoperative evaluation to 74.2 ± 11.6 at one year (p < 0.00001) and to 83.9 ± 10.4 at 5 years follow up (p < 0.001). Mean IKDC values at the last follow-up were 80.3 ± 14.2, showing no statistical differences with those obtained at five-year follow-up. Tegner Activity Scale values increased from 2.8 ± 1.1 preoperatively to 4.1 ± 1.1 (p < 0.0001) after one year and to 6 ± 1.1 at five years (p < 0.0001). Mean Tegner Activity Scale values decreased to 4.8 ± 1.4 at the last follow-up. EQ-VAS evaluation showed superposable results comparing the 5 years evaluation with the ones at a medium follow up of 162 ± 27 months.DiscussionThe most important finding is the reliability at long-term of ACI technique, which in our series gave excellent clinical results. No statistical differences were observed between first- and second-generation. Clinical outcomes were significantly better for defects in the femoral condyles, influenced by age (worse results over 30 years old).ConclusionsACI represents a valid technique for chondral and osteochondral lesions of the knee in a population heterogeneous for age, sex and activity level with good results even at a long term follow up.     

Functional Medium-Term Results After Autologous Matrix-Induced Chondrogenesis for Osteochondral Lesions of the Talus: A 5-Year Prospective Cohort Study

Autologous matrix-induced chondrogenesis (AMIC) has gained popularity in the treatment of osteochondral lesions of the talus. Previous studies have presented promising short-term results for AMIC talar osteochondral lesion repair, a 1-step technique using a collagen type I/III bilayer matrix. The aim of the present study was to investigate the mid-term effects. The 5-year results of a prospective cohort study are presented. All patients underwent an open AMIC procedure for a talar osteochondral lesion. Data analysis included general demographic data, preoperative magnetic resonance imaging findings, intraoperative details, and German version of the Foot Function Index (FFI-D) scores preoperatively and at 1 and 5 years after surgery. The primary outcome variable was the longitudinal effect of the procedure, and the influence of various variables on the outcome was tested. Of 47 consecutive patients, 21 (45%) were included. Of the 21 patients, 8 were female (38%) and 13 were male (62%), with a mean age of 37 ± 15 (range 15 to 62) years and a body mass index of 26 ± 5 (range 20 to 38) kg/m². The defect size was 1.4 ± 0.9 (range 0.2 to 4.0) cm². The FFI-D decreased significantly from preoperatively to 1 year postoperatively (56 ± 18 versus 33 ± 25; p = .003), with a further, nonsignificant decrease between the 1- and 5-year follow-up examination (33 ± 25 versus 24 ± 21; p = .457). Similar results were found for the FFI-D subscales of function and pain. The body mass index and lesion size showed a positive correlation with the preoperative FFI-D overall and subscale scores. These results showed a significant improvement in pain and function after the AMIC procedure, with a significant return to sports by the 5-year follow-up point. The greatest improvement overall was seen within the first year; however, further clinical satisfaction among the patients was noticeable after 5 years.     

Cartilage repair evolution in post-traumatic osteochondral lesions of the talus: from open field autologous chondrocyte to bone-marrow-derived cells transplantation

The aims of this study are to describe evolution in cartilage repair from open field autologous chondrocyte implantation to regeneration by arthroscopic bone-marrow-derived cells (BMDCs) “one step” technique; to present the results of a series of patients consecutively treated and to compare in detail the different techniques used in order to establish the advantages obtained with the evolution in cartilage regenerative methods.81 patients (mean age 30 ± 8 years) were evaluated in this study. Patient assessment included clinical AOFAS score, X-rays and MRI preoperatively and at different established follow-ups. All the lesions were >1.5 cm² and received open autologous chondrocyte implantation (10 cases), arthroscopic autologous chondrocyte implantation (46 cases), and “one step” arthroscopic repair by BMDC transplantation (25 cases). For arthroscopic repair techniques a hyaluronic acid membrane was used to support cells and specifically designed instrumentation was developed. Patients of all the three groups underwent a second arthroscopy with a bioptic cartilage harvest at 1 year follow-up.Mean AOFAS score before surgery was 57.1 ± 17.2 and 92.6 ± 10.5 (P < 0.0005) at mean 59.5 ± 26.5 months. A similar pattern of AOFAS improvement in results was found in the three different techniques. Histological evaluations highlighted collagen type II and proteoglycan expression.The cartilage repair techniques described were able to provide a repair tissue which closely approximates the characteristics of the naive hyaline cartilage. Evolution in surgical technique, new biomaterials and more recently the use of BMDCs permitted a marked reduction in procedure morbidity and costs up to a “one step” technique able to overcome all the drawbacks of previous repair techniques.     

Conventional Versus Computer-Assisted Technique for Total Knee Arthroplasty: A Minimum of 5-Year Follow-up of 200 Patients in a Prospective Randomized Comparative Trial

In the literature, studies of computer-assisted total knee arthroplasty (TKA) after mid-term period are not conclusive and long-term data are rare. In a prospective, randomized, comparative study 100 conventional TKAs (group REG) were compared with 100 computer-assisted TKAs (group NAV). Minimum follow-up was 5 years. No difference in implant failure was found with 1.1% in group NAV versus 4.6% in group REG (P = 0.368). Group NAV showed a significantly less mean deviation of mechanical limb axis (P = 0.015), more TKAs (90% versus 81% in group REG) were within 3° varus/valgus and a higher tibial slope and lateral distal femoral angle (LDFA) accuracy was found (P ≤ 0.034). Clinical investigational parameters showed no differences (P ≥ 0.058). Insall and HSS score total were also higher in group NAV (P ≤ 0.016).