Full-thickness Chondral Defects Research Articles

Results after microfracture of full-thickness chondral defects in different compartments in the knee

To determine if the clinical results after microfracture of full-thickness cartilage lesions deteriorate over a period of 36 months. Between 1999 and 2002 85 patients (mean age 39.5 years) with full-thickness cartilage lesions underwent the microfracture procedure and were evaluated preoperatively and 6, 18 and 36 months after surgery. Exclusion criteria were meniscal pathologies, axial malpositioning and ligament instabilities. Baseline clinical scores were compared with follow-up data by paired Wilcoxon-tests for the modified Cincinnati knee and the International Cartilage Repair Society (ICRS)-score. The effects of the lesion localization and Magnetic resonance imaging (MRI) parameters were evaluated using the Pearson correlation and independent samples tests. Both scores revealed significant improvement 18 months after microfracture (P<0.0001). Within the second 18 months after surgery there was a significant deterioration in the ICRS-score (P<0.0001). The best results could be observed in chondral lesions of the femoral condyles. Defects in other areas of the knee deteriorated between 18 and 36 months after microfracture. MRI 36 months after surgery revealed best defect filling in lesions on the femoral condyles with significant difference in the other areas (P<0.02). The Pearson coefficient of correlation between defect filling and ICRS-score was 0.84 and significant at the 0.01 level. Microfracture is a minimal invasive method with good short-term results in the treatment of small cartilage defects. A deterioration of the results starts 18 months after surgery and is most evident in the ICRS-score. The best prognostic factors have young patients with defects on the femoral condyles.

Minced cartilage without cell culture serves as an effective intraoperative cell source for cartilage repair

Traumatic articular cartilage injuries heal poorly and may predispose patients to the early onset of osteoarthritis. One current treatment relies on surgical delivery of autologous chondrocytes that are prepared, prior to implantation, through ex vivo cell expansion of cartilage biopsy cells. The requirement for cell expansion, however, is both complex and expensive and has proven to be a major hurdle in achieving a widespread adoption of the treatment. This study presents evidence that autologous chondrocyte implantation can be delivered without requiring ex vivo cell expansion. The proposed improvement relies on mechanical fragmentation of cartilage tissue sufficient to mobilize embedded chondrocytes via increased tissue surface area. Our outgrowth study, which was used to demonstrate chondrocyte migration and growth, indicated that fragmented cartilage tissue is a rich source for chondrocyte redistribution. The chondrocytes outgrown into 3-D scaffolds also formed cartilage-like tissue when implanted in SCID mice. Direct treatment of full-thickness chondral defects in goats using cartilage fragments on a resorbable scaffold produced hyaline-like repair tissue at 6 months. Thus, delivery of chondrocytes in the form of cartilage tissue fragments in conjunction with appropriate polymeric scaffolds provides a novel intraoperative approach for cell-based cartilage repair.

A prospective, ranomised study comparing two techniques of autologous chondrocyte implantation for osteochondral defects in the knee: Periosteum covered versus type I/III collagen covered

Introduction The results for autologous chondrocyte implantation (ACI) in the treatment of full thickness chondral defects in the knee are encouraging. At present two techniques have been described to retain the chondrocyte suspension within the defect. The first involves using a periosteal cover (ACI-P) and the second involves using a type I/III collagen membrane (ACI-C). To the authors knowledge there are no comparative studies of these two techniques in the current literature. We have therefore undertaken such a study to establish if there is a difference between the 2 techniques based on a clinical and arthroscopic assessment. Methods A total of 68 patients with a mean age of 30.52 years with symptomatic articular cartilage defects were randomised to have either ACI-P (33 patients) or ACI-C (35 patients). The mean defect size was 4.54 cm 2. All patients were followed up at 24 months. Results A clinical and functional assessment showed that 74% of patients had a good or excellent result following the ACI-C compared with 67% after the ACI-P at 2 years. Arthroscopy at 1 year also demonstrated similar results for both techniques. However, 36.4% of the ACI-P grafts required shaving for hypertrophy compared with none for the ACI-C grafts at 1 year. Discussion This study has shown no statistical difference between the clinical outcome of ACI-C versus ACI-P at 2 years. A significant number of patients who had the ACI-P required shaving of a hypertrophied graft. We conclude that there is no advantage in using periosteum as a cover for retaining chondrocytes within an osteochondral defect; as a result we advocate the use of an alternative cover such as a manufactured type I/III collagen membrane.

Cartilage Healing After Microfracture in Osteoarthritic Knees

To evaluate the clinical and radiologic results, second-look arthroscopic findings, histologic evaluation, and results of immunohistochemical staining and the Western blotting test for type II collagen after microfracture for full-thickness chondral defects in patients with osteoarthritic knee. Between October 1997 and December 1998, 49 knees in 46 patients who had moderate osteoarthritic changes underwent microfracture; 44 patients (47 cases) had second-look arthroscopy and biopsy performed 1 year after surgery. The clinical outcomes were assessed by use of Baumgaertner's 9-point scale and joint space changes were measured radiographically; 18 knees underwent immunohistochemical study and 21 knees underwent Western blotting tests to identify formation of type II collagen. Significant improvements were noted for the parameters of daily living activity and pain (P < .05). The joint spaces were widened by 1.06 mm on standing anteroposterior and by 1.37 mm on standing lateral radiographs, which showed statistical significance (P < .05). Individual defects were filled with white tissue resembling cartilage on second-look arthroscopy, and the cartilage healing was found by histologic evaluation. Type II collagen formation was identified qualitatively by immunohistochemical staining. Quantitative collagen formation by Western blotting showed 44% growth compared with the normal control. This healed tissue is a combination, or hybrid, of fibrocartilage and hyaline-like cartilage, and it is shown to contain type II collagen on immunohistochemical staining and the Western blotting test. Patients with full-thickness chondral defects in the osteoarthritic knee can have improved function and see an increase in joint space after microfracture. Cartilaginous tissue containing type II collagen is formed after the microfracture procedure in the osteoarthritic knee. Level IV, retrospective case series.

Regenerated soft tissue survival using repulsive force of magnetized devices: preliminary report

BackgroundLarge full-thickness cartilage defects in the weight-bearing area are difficult to treat. A new therapeutic strategy called the total joint regeneration (TJR) system is proposed for such large defects. The purpose of this study was to evaluate the effects of the magnet-type TJR device using a rabbit model. MethodsThe magnetized devices were implanted in fullthickness chondral defects on the patellofemoral joints of rabbits. The specimens and surrounding tissue were harvested 4weeks after the surgery and observed macroscopically and histologically. The thickness of the regenerated soft tissue on the femur joint surface was measured and compared. The difference between the two groups (magnetized and nonmagnetized) was significant at P<0.05. ResultsSome cartilaginous regeneration was seen in the repair tissue. However, about half of the experimental knees were omitted from the study because of some trouble, such as loosening of the device or patella fracture. ConclusionsThis study suggested that magnetized devices were useful for regenerating soft tissue by maintaining the joint space. Some hyaline cartilage-like tissue was regenerated partially on the magnetized devices. It was suggested that these devices might be useful for cartilage regeneration if the devices are improved.

CHITOSAN-GLYCEROL PHOSPHATE/BLOOD IMPLANTS IMPROVE HYALINE CARTILAGE REPAIR IN OVINE MICROFRACTURE DEFECTS

Background: Microfracture is a surgical procedure that is used to treat focal articular cartilage defects. Although joint function improves following microfracture, the procedure elicits incomplete repair. As blood clot formation in the microfracture defect is an essential initiating event in microfracture therapy, we hypothesized that the repair would be improved if the microfracture defect were filled with a blood clot that was stabilized by the incorporation of a thrombogenic and adhesive polymer, specifically, chitosan. The objectives of the present study were to evaluate (1) blood clot adhesion in fresh microfracture defects and (2) the quality of the repair, at six months postoperatively, of microfracture defects that had been treated with or without chitosan-glycerol phosphate/blood clot implants, using a sheep model. Methods: In eighteen sheep, two 1-cm2 full-thickness chondral defects were created in the distal part of the femur and treated with microfracture; one defect was made in the medial femoral condyle, and the other defect was made in the trochlea. In four sheep, microfracture defects were created bilaterally; the microfracture defects in one knee received no further treatment, and the microfracture defects in the contralateral knee were filled with chitosan-glycerol phosphate/autologous whole blood and the implants were allowed to solidify. Fresh defects in these four sheep were collected at one hour postoperatively to compare the retention of the chitosan-glycerol phosphate/blood clot with that of the normal clot and to define the histologic characteristics of these fresh defects. In the other fourteen sheep, microfracture defects were made in only one knee and either were left untreated (control group; six sheep) or were treated with chitosan-glycerol phosphate/blood implant (treatment group; eight sheep), and the quality of repair was assessed histologically, histomorphometrically, and biochemically at six months postoperatively. Results: In the defects that were examined one hour postoperatively, chitosan-glycerol phosphate/blood clots showed increased adhesion to the walls of the defects as compared with the blood clots in the untreated microfracture defects. After histological processing, all blood clots in the control microfracture defects had been lost, whereas chitosanglycerol phosphate/blood clot adhered to and was partly retained on the surfaces of the defect. At six months, defects that had been treated with chitosan-glycerol phosphate/blood were filled with significantly more hyaline repair tissue (p < 0.05) compared with control defects. Repair tissue from medial femoral condyle defects that had been treated with chitosan-glycerol phosphate/blood contained more cells and more collagen compared with control defects and showed complete restoration of glycosaminoglycan levels. Conclusions: Solidification of a chitosan-glycerol phosphate/blood implant in microfracture defects improved cartilage repair compared with microfracture alone by increasing the amount of tissue and improving its biochemical composition and cellular organization. Clinical Relevance: The use of chitosan-glycerol phosphate/blood implants in conjunction with microfracture can improve the structural and compositional properties of repaired cartilage. These effects may result in better integration, improved biomechanical properties, and longer durability of the repair tissue.

Chitosan-Glycerol Phosphate/Blood Implants Improve Hyaline Cartilage Repair in Ovine Microfracture Defects

Microfracture is a surgical procedure that is used to treat focal articular cartilage defects. Although joint function improves following microfracture, the procedure elicits incomplete repair. As blood clot formation in the microfracture defect is an essential initiating event in microfracture therapy, we hypothesized that the repair would be improved if the microfracture defect were filled with a blood clot that was stabilized by the incorporation of a thrombogenic and adhesive polymer, specifically, chitosan. The objectives of the present study were to evaluate (1) blood clot adhesion in fresh microfracture defects and (2) the quality of the repair, at six months postoperatively, of microfracture defects that had been treated with or without chitosan-glycerol phosphate/blood clot implants, using a sheep model. In eighteen sheep, two 1-cm2 full-thickness chondral defects were created in the distal part of the femur and treated with microfracture; one defect was made in the medial femoral condyle, and the other defect was made in the trochlea. In four sheep, microfracture defects were created bilaterally; the microfracture defects in one knee received no further treatment, and the microfracture defects in the contralateral knee were filled with chitosan-glycerol phosphate/autologous whole blood and the implants were allowed to solidify. Fresh defects in these four sheep were collected at one hour postoperatively to compare the retention of the chitosan-glycerol phosphate/blood clot with that of the normal clot and to define the histologic characteristics of these fresh defects. In the other fourteen sheep, microfracture defects were made in only one knee and either were left untreated (control group; six sheep) or were treated with chitosan-glycerol phosphate/blood implant (treatment group; eight sheep), and the quality of repair was assessed histologically, histomorphometrically, and biochemically at six months postoperatively. In the defects that were examined one hour postoperatively, chitosan-glycerol phosphate/blood clots showed increased adhesion to the walls of the defects as compared with the blood clots in the untreated microfracture defects. After histological processing, all blood clots in the control microfracture defects had been lost, whereas chitosanglycerol phosphate/blood clot adhered to and was partly retained on the surfaces of the defect. At six months, defects that had been treated with chitosan-glycerol phosphate/blood were filled with significantly more hyaline repair tissue (p < 0.05) compared with control defects. Repair tissue from medial femoral condyle defects that had been treated with chitosan-glycerol phosphate/blood contained more cells and more collagen compared with control defects and showed complete restoration of glycosaminoglycan levels. Solidification of a chitosan-glycerol phosphate/blood implant in microfracture defects improved cartilage repair compared with microfracture alone by increasing the amount of tissue and improving its biochemical composition and cellular organization.

Autologous Chondrocyte Implantation versus Debridement for Treatment of Full-Thickness Chondral Defects of the Knee

Background Studies that compare the effectiveness of different cartilage repair treatments are needed to update treatment algorithms. Hypothesis Autologous chondrocyte implantation provides greater improvement in overall condition score than does debridement at a minimum of 3 years’ follow-up. Study Design Cohort study; Level of evidence, 3. Methods Cohorts for debridement and autologous chondrocyte implantation each included 58 Cartilage Repair Registry patients who met study criteria. A retrospective analysis was performed on prospectively collected baseline and follow-up data. Results Patients in the autologous chondrocyte implantation and debridement groups had similar demographics and chondral lesions at baseline. However, more autologous chondrocyte implantation patients failed a previous debridement or marrow stimulation procedure than did debridement patients. Follow-up outcome assessments were completed by 54 autologous chondrocyte implantation patients and 42 debridement patients. Eighty-one percent of the autologous chondrocyte implantation patients and 60% of the debridement patients reported median improvements of 5 points and 2 points, respectively, in the overall condition score. Autologous chondrocyte implantation patients also reported greater improvements in the median pain and swelling scores than did debridement patients. The treatment failure rate was the same for both autologous chondrocyte implantation and debridement patients. Eighteen autologous chondrocyte implantation patients and 1 debridement patient had at least 1 subsequent operation. Conclusion Although patients treated with debridement for symptomatic, large, focal, chondral defects of the distal femur had some functional improvement at follow-up, patients who received autologous chondrocyte implantations obtained higher levels of knee function and had greater relief from pain and swelling at 3 years.

Autologous osteochondral transplantation for the treatment of chondral defects of the knee

Full-thickness chondral defects of weight-bearing articular surfaces of the knee are a difficult condition to treat. Our aim is to evaluate the mid- and long-term functional outcome of the treatment of osteochondral defects of the knee with autologous osteochondral transplantation with the OATS technique. Thirty-six patients (37 procedures) were included in this study. Twenty-three patients were male and thirteen were female with a mean age of 31.9 years (range: 18–48 years). The cause of the defect was OCD in 10 cases, AVN in 2, lateral patellar maltracking in 7, while in the remaining 17 patients the defect was post-traumatic. The lesion was located on the femoral condyles in 26 cases and the patellofemoral joint in the remaining 11. The average area covered was 2.73 cm2 (range: 0.8–12 cm2) and patients were followed for an average of 36.9 months (range: 18–73 months).The average score in their Tegner Activity Scale was 3.76 (range: 1–8), while their score in Activities of Daily Living Scale of the Knee Outcome Survey ranged from 18 to 98 with an average of 72.3. Thirty-two out of 37 patients (86.5%) reported improvement of their pre-operative symptoms. All but 5 patients returned to their previous occupation while 18 went back to sports. No correlation was found between patient age at operation, the size or site of the chondral lesion and the functional outcome.We believe that autologous osteochondral grafting with the OATS technique is a safe and successful treatment option for focal osteochondral defects of the knee. It offers a very satisfactory functional outcome and does not compromise the patient's future options.

Comparative Evaluation of Autologous Chondrocyte Implantation and Mosaicplasty

To compare the respective performance and effectiveness of autologous chondrocyte implantation (ACI) and mosaicplasty at resurfacing local full-thickness chondral defects of the knee. Randomized clinical trial. Multicenter trial at orthopedic clinics and university hospitals conducted from 1997 to 2000. A population of patients selected according to eligibility criteria of age, traumatic origin of the defect, its localization, size, and gravity, and above all, no previous surgical treatment of the lesion. Forty-seven patients were randomly assigned to ACI or mosaicplasty and subjected to arthroscopic debridement of the lesion at the time of enrollment. They were called for surgery 6 months after the initial debridement. Improved knee functionality as assessed by repeated clinical evaluation based on the International Knee Documentation Committee Scale and the Lysholm Knee Scoring Scale. Fourteen patients (31.8%) experienced substantial improvement following the initial debridement and, being clinically cured, received no further treatment. Seven patients (15.9%) were lost to follow-up. Among the 23 patients (52.3%) who could effectively be evaluated, a complete recovery (ie, Lysholm Knee Scoring Scale score, 90-100) was observed upon clinical examination in 88% of the mosaicplasty-treated patients and in 68% of the ACI-treated ones (P = 0.093). Although the low power of our study prevents definitive conclusions, ACI and mosaicplasty are cartilage repair techniques that are clinically equivalent and similar in performance. The high percentage of spontaneous improvement ((1/3) of the patients) observed after simple debridement calls into question the need for prompt surgical treatment of patients with lesions similar to those included in this clinical trial. Moreover, this finding warrants further investigation, ideally through randomized clinical trials in which patients subjected to debridement alone are compared with patients undergoing reconstructive surgery.

Clinical Results in Patellofemoral Full Thickness Chondral Defects Treated with Hyalograft®-C: A Prospective Study at 2-years Follow-up (SS-61)

Clinical Results in Patellofemoral Full Thickness Chondral Defects Treated with Hyalograft®-C: A Prospective Study at 2-years Follow-up (SS-61)

Chondral Defect Repair after the Microfracture Procedure

Background The extent and time course of chondral defect healing after microfracture in humans are not well described. Although most physicians recommend a period of activity and weightbearing restriction to protect the healing cartilage, there are limited data on which to base decisions regarding the duration of such restrictions. Hypothesis Evaluation of the status of chondral defect repair at different time points after microfracture in a primate model may provide a rationale for postoperative activity recommendations. Study Design Descriptive laboratory study. Methods Full-thickness chondral defects created on the femoral condyles and trochlea of 12 cynomolgus macaques were treated with microfracture and evaluated by gross and histologic examination at 6 and 12 weeks. Results At 6 weeks, there was limited chondral repair and ongoing resorption of subchondral bone. By 12 weeks, the defects were completely filled and showed more mature cartilage and bone repair. Conclusion In the primate animal model, significant improvements in the extent and quality of cartilage repair were observed from the 6- to 12-week time points after microfracture. Clinical Relevance The poor status of the defect repair at 6 weeks and the ongoing healing observed from the 6- to 12-week time points may indicate that the repair is vulnerable during this initial postoperative period. Assuming the goal of postoperative weightbearing and activity restriction in patients after microfracture is to protect immature repair tissue, this study lends support to extending such recommendations longer than 6 weeks.

Tissue engineering of cartilage using an injectable and adhesive chitosan-based cell-delivery vehicle

Adult articular cartilage shows a limited intrinsic repair response to traumatic injury. To regenerate damaged cartilage, cell-assisted repair is thus viewed as a promising therapy, despite being limited by the lack of a suitable technique to deliver and retain chondrogenic cells at the defect site. We have developed a cytocompatible chitosan solution that is space-filling, gels within minutes, and adheres to cartilage and bone in situ. This unique combination of properties suggested significant potential for its use as an arthroscopically injectable vehicle for cell-assisted cartilage repair. The primary goal of this study was to assess the ability of this polymer system, when loaded with primary articular chondrocytes, to support cartilage formation in vitro and in vivo. The chitosan gel was cultured in vitro, with and without chondrocytes, as well as injected subcutaneously in nude mice to form subcutaneous dorsal implants. In vitro and in vivo constructs were collectively analyzed histologically, for chondrocyte mRNA and protein expression, for biochemical levels of glycosaminoglycan, collagen, and DNA, and for mechanical properties. Resulting tissue constructs revealed histochemical, biochemical and mechanical properties comparable to those observed in vitro for primary chondrocytes cultured in 2% agarose. Moreover, the gel was retained after injection into a surgically prepared, rabbit full-thickness chondral defect after 1 day in vivo, and in rabbit osteochondral defects, up to 1 week. The in situ-gelling chitosan solution described here can support in vitro and in vivo accumulation of cartilage matrix by primary chondrocytes, while persisting in osteochondral defects at least 1 week in vivo.

Arthroscopic microfracture of chondral defects of the knee: A comparison of two postoperative treatments

We hypothesized that the treatment of focal, full-thickness chondral defects by an identical method of arthroscopic microfracture but with different postoperative regimens would produce similar results. Case control study, retrospective cohort. Fifty patients treated over a 6-year period (1993 to 1999) with a focal, less than 2-cm 2 , full-thickness chondral defect of either the medial or lateral femoral condyle of the knee had arthroscopic surgery to debride loose adjacent cartilage flaps and abortive fibrocartilage from the crater in conjunction with microfracture of the subchondral plate using a hand awl. Postoperatively, 1 group was treated with non-weight bearing and continuous passive motion (CPM) for 6 weeks (group I), and the other group was allowed weight bearing as tolerated and did not use CPM (group II). Results of treatment were assessed by the Lysholm knee rating scale augmented by the Tegner method of activity evaluation. Results were analyzed by independent t test or chi-square test with significance assumed for P < .05. Forty-three of 50 patients were evaluated at a minimum of 2 years after surgery (mean, 4.2 years; range, 2 to 9 years). The mean age was 39.7 years (range, 16 to 66 years) and there were 19 female and 24 male patients. For group I, Lysholm scores were 37 preoperative, 81 postoperative, and Tegner scores were 3 and 6, respectively. Group II Lysholm scores were 33 preoperative, 85 postoperative, and Tegner scores 3 and 6, respectively. No significant differences between groups were noted. In relatively small full-thickness chondral defects of the femoral condyles treated by microfracture, this study found no differences in results comparing 2 rehabilitation regimens differing by weight-bearing status and use of CPM. Level III, Case Control Study.

KNORPELSCHÄDEN IM SPORT: Mosaicplasty in active sportsmen

Summary Autologous osteochondral transplantation (mosaicplasty) fills articular surface defects with hyaline cartilage-like tissue to resurface the defected area. 96 high level athletes with full-thickness chondral defects were treated with mosaicplasty. Most of these defects (79 cases) were located in the knee, 15 in the talus and in 2 in the elbow capitellum. Osteoarthritic degenerative changes of Fairbank's grade I or II after were observed in 44% of the affected joints. The average size of the chondral defects in knees treated with mosaicplasty was an average 2 cm 2 (1–5.5 cm 2 ) but in 3 cases it exceeded 4 cm 2 . In the talus the mean defect size was 1.5 cm 2 (0.5–2.5 cm 2 ) while in the elbow capitellum the size of the two defects was 1cm 2 and 1.5 cm 2 . The mean follow-up time was 4.5 ± 3.1 years (range 1–10 years). The mean patients' age was 27 ± 6.5 years (range 14-39 years). There were 55 male and 41 female patients. In the knee defect group the mean modified HSS score preoperatively was 62 ± 19.5 (47–82) and at the last postoperative follow-up was 87 ± 18.9 (64–100) points. The mean preoperative Lysholm score was 66 ± 14.6 (49–84) and the last postoperative score was 91 ± 13.2 (68–100). In the talus defect group the mean preoperative Hanover score was 73 ± 12.4 (56–81) and the mean postoperative score was 92 ± 8.6 (84–102). The time to return to the desired level of sports activities averaged 4.2 ± 2.4 months (3–10 months). Sixty-seven out of 96 patients resumed the same level of athletic activity, 18% a lower level and 12% failed to return to sports activities. Only 8% of the athletes rated the post operative knee function and symptom scores as being worse than that recorded prior to mosaicplasty. Autologous osteochondral transplantation (mosaicplasty) provides favorable mid-term functional results in high level athletes even in those with radiographic evidence of osteoarthritic changes or those with large defects as a salvage procedure.

KNORPELSCHÄDEN IM SPORT: Die Mikrofraktur – Eine knochenmarkstimulierende Technik zur Behandlung von Knorpeldefekten

Summary Subchondral bone plate microfracture technique (Steadman) has shown to enhance chondral resurfacing by providing a suitable environment for tissue regeneration and taking advantage of the body's own healing potential. Microfracture technique belongs to the bone marrow stimulating methods like abrasion arthroplasty or subchondral bone drilling. Using a specially designed awl or pick, multiple perforations (microfractures) are placed 3 to 4 mm apart and about 4 mm deep into the subchondral bone to reach a zone of vascularization. The formation of a fibrin clot (super clot) containing the desired pluripotential stem cells is stimulated. This clot then differentiates and remodels, resulting in a durable fibrocartilage repair tissue. The arthroscopic awls produce essentially no thermal necrosis of the bone compared to hand-driven or motorized drills. In contrary to drills, it is possible with differently curved awls to reach and treat every area of the knee joint or even of the upper ankle or shoulder joint. Between 1992 and 1998 this technique has been used in 351 cases. 162 patients were provided a questionnaire for subjective follow up with a minimum or 3 up to 6 years (mean 4.4). Pain was the parameter with the greatest improvement. 78% of patients were improved, 18% remained unchanged and 4% were worse. Microfracture is a viable option for the treatment of full thickness chondral defects.

Arthroscopic autogenous osteochondral transplantation for treating knee cartilage defects: A 2- to 5-year follow-up study

Purpose: The purpose of this retrospective analysis was to evaluate the medium-term results of arthroscopic treatment of chondral and osteochondral lesions of the knee with autogenous osteochondral transplantation (AOT). Type of Study: Case series. Methods: Thirty-three skeletally mature patients with symptomatic, full-thickness cartilage lesions of the femoral condyles, between 1 and 2.5 cm in diameter, were treated with arthroscopic AOT. Grafts were harvested from the superior and lateral intercondylar notch and press-fit into holes drilled into the defect. All patients were evaluated both preoperatively and postoperatively with the Lysholm knee score, International Knee Documentation Committee (IKDC) Standard Evaluation Form, and knee joint radiographs. Results: Thirty patients of a mean age of 44.6 years were followed-up for a mean time of 45.1 months. Symptom duration ranged from 1 month to 15 years (median, 9.5 months). The mean Lysholm score significantly improved from 43.6 preoperatively to 87.5 postoperatively (P < .001). Excellent or good outcome was accomplished in 25 of the patients (83%). Using the IKDC assessment, 26 of the patients (87%) reported their knee as being normal or nearly normal. Repeat arthroscopy with needle biopsy of the graft was performed in 9 patients. Seven of these had complete healing and 2 partial healing. The histologic examination revealed viable chondrocytes and normal hyaline cartilage in the completely healed cases. Congruency of the articular surface was restored in 11 of 12 patients (92%) who underwent magnetic resonance imaging examination. Abnormal marrow signal in the subchondral bone beneath the region of cartilage repair was present in 9 of 12 patients (75%), even 4 years after the procedure. Conclusions: Arthroscopic AOT is an effective and safe method of treating symptomatic full-thickness chondral defects of the femoral condyles in appropriately selected cases. However, further studies with long-term follow-up are needed to determine if the grafted area will maintain structural and functional integrity over time. Level of Evidence: Level IV, therapeutic, case series (no, or historical, control group). Purpose: The purpose of this retrospective analysis was to evaluate the medium-term results of arthroscopic treatment of chondral and osteochondral lesions of the knee with autogenous osteochondral transplantation (AOT). Type of Study: Case series. Methods: Thirty-three skeletally mature patients with symptomatic, full-thickness cartilage lesions of the femoral condyles, between 1 and 2.5 cm in diameter, were treated with arthroscopic AOT. Grafts were harvested from the superior and lateral intercondylar notch and press-fit into holes drilled into the defect. All patients were evaluated both preoperatively and postoperatively with the Lysholm knee score, International Knee Documentation Committee (IKDC) Standard Evaluation Form, and knee joint radiographs. Results: Thirty patients of a mean age of 44.6 years were followed-up for a mean time of 45.1 months. Symptom duration ranged from 1 month to 15 years (median, 9.5 months). The mean Lysholm score significantly improved from 43.6 preoperatively to 87.5 postoperatively (P < .001). Excellent or good outcome was accomplished in 25 of the patients (83%). Using the IKDC assessment, 26 of the patients (87%) reported their knee as being normal or nearly normal. Repeat arthroscopy with needle biopsy of the graft was performed in 9 patients. Seven of these had complete healing and 2 partial healing. The histologic examination revealed viable chondrocytes and normal hyaline cartilage in the completely healed cases. Congruency of the articular surface was restored in 11 of 12 patients (92%) who underwent magnetic resonance imaging examination. Abnormal marrow signal in the subchondral bone beneath the region of cartilage repair was present in 9 of 12 patients (75%), even 4 years after the procedure. Conclusions: Arthroscopic AOT is an effective and safe method of treating symptomatic full-thickness chondral defects of the femoral condyles in appropriately selected cases. However, further studies with long-term follow-up are needed to determine if the grafted area will maintain structural and functional integrity over time. Level of Evidence: Level IV, therapeutic, case series (no, or historical, control group).

Microfracture Chondroplasty:

Techniques to treat full-thickness chondral defects include abrasion, drilling, autografts, allografts, and cell transplantation. The “microfracture” technique was developed to enhance chondral resurfacing by providing a suitable environment for new tissue formation and taking advantage of the body's own healing potential. Specially designed awls are used to make multiple perforations, or “microfractures,” into the subchondral bone plate. Perforations are made as close together as possible, but not so close that one breaks into another, approximately three to four millimeters apart. Integrity of the subchondral bone plate must be maintained. The released marrow elements (including mesenchymal stem cells, growth factors, and other healing proteins) form a “super clot” which provides an enriched environment for new tissue formation. The rehabilitation program is crucial to optimize the results of the surgery. It promotes the ideal physical environment for the mesenchymal stem cells to differentiate into articular cartilage-like cells, leading to development of a durable repair cartilage that fills the original defect.

Treatment of large full-thickness chondral defects of the knee with autologous chondrocyte implantation

Treatment of large full-thickness chondral defects of the knee with autologous chondrocyte implantation

Paper #125 Marrow stimulation techniques versus autologous chondrocyte implantation for treatment of full-thickness chondral defects of the knee: comparison of patient outcomes at 3-5 years

Autologous cultured chondrocyte implantation (ACI), for articular cartilage lesions of the distal femur, generally demonstrates effectiveness in 80-85% of cases. However, no studies have compared these results to those of marrow stimulation techniques (MST): abrasion, drilling, or microfracture. The purpose of this multicenter, prospective study was to compare patient reported outcomes at a minimum of three years between patients treated with autologous chondrocyte implantation and marrow stimulation techniques.