Matthias Steinwachs

Characteristic Complications After Autologous Chondrocyte Implantation for Cartilage Defects of the Knee Joint

Background Although autologous chondrocyte implantation (ACI) is a well-established therapy for the treatment of isolated cartilage defects of the knee joint, little is known about typical complications and their treatment after ACI. Hypothesis Unsatisfactory outcome after ACI is associated with technique-related typical complications. Study Design Case series; Level of evidence, 4. Methods A total of 309 consecutive patients with 349 ACI procedures of the knee joint were analyzed. Three different ACI techniques were used: periosteum-covered ACI in 52 cases (14.9%), Chondrogide (Geistlich Biomaterials, Wolhusen, Switzerland) membrane-covered ACI in 215 cases (61.6%), and a 3-dimensional matrix-associated ACI (BioSeed-C, Biotissue Technologies, Freiburg, Germany) in 82 cases (23.5%). In 52 patients, revision surgery was performed for persistent clinical problems. These patients were analyzed for defect size and location, technique of ACI, and intraoperative findings during revision surgery. The mean time of follow-up for patients after ACI was 4.5 years (standard deviation, ±1.5). Results Four typical major complications were identified: hypertrophy of the transplant, disturbed fusion of the regenerative cartilage and the healthy surrounding cartilage, insufficient regenerative cartilage, and delamination. These diagnoses covered a total of 88.5% of the patients who underwent revision surgery. The overall complication rate was highest in the group of patients treated with periosteum-covered ACI (P = .008). The incidence of symptomatic hypertrophy was 5.2% for all techniques and defect locations; the highest incidence was in patients treated with periosteum-covered ACI (15.4%) (P = .001). The incidence of disturbed fusion was highest in the Chondrogide-covered ACI (3.7%) and the matrix-associated ACI group (4.8%). Concerning the incidence of complications by defect location, there was a tendency for increased complications in patellar defects (P = .095). Within the patellar defects group, no correlation was found for the occurrence of delamination, insufficient regeneration, and disturbed fusion. As a statistical trend, an increased rate of hypertrophy was found for patellar defects (P = .091). Conclusion A major proportion of complications after ACI can be summarized by 4 major diagnoses (symptomatic hypertrophy, disturbed fusion, delamination, and graft failure). Among those, the overall complication rate and incidence of hypertrophy of the transplant were higher for periosteum-covered ACI. Furthermore, an increased rate of symptomatic hypertrophy was found for patellar defects. Therapeutic concepts need to be developed to treat these typical complications of ACI.

Arthroscopic Management of Osteochondral Lesions of the Talus: Results of Drilling and Usefulness of Magnetic Resonance Imaging Before and After Treatment

Since the advent of operative ankle arthroscopy and magnetic resonance imaging (MRI) specific treatment of osteochondritis dissecans of the talus has progressed rapidly. Drilling is still the treatment of choice in early stages of osteochondritis dissecans of the talus. Rear-entry guides and preoperative planning with MRI have led to better results with this kind of treatment. Within 5 years, 42 patients (26 male and 16 female) underwent arthroscopic treatment of osteochondritis dissecans of the talus, 22 underwent percutaneous drilling, 13 cancellous bone grafting, 4 refixation, and 3 curettage. The average age of the patients was 28 years (range, 11 to 53 years). A clinical score system was used in a clinical and MRI follow-up of 19 of the patients with K-wire drilling. Up to 100 points are given in the categories pain, stability/insecurity, efficiency/pain-free walking distance, gait, differences in circumference, range of motion, and power. There was a history of trauma in 31 of the 42 patients. The majority of lesions (24 cases) were localized at the lateral talus, and these patients all had trauma. In 11 of the 18 lesions at the medial talus, there was no evidence of trauma. The 19 patients in the follow-up achieved an average of 87 points. K-wire drilling represents the chief component of early stages with intact or partially fractured cartilage surface, whereas arthroscopically controlled cancellous bone grafts after curettage are used in grade II stages only. Results of K-wire drilling are not worse than those of cancellous bone grafts; this is attributable to a generous perforation of the sclerosis. This has contributed to an improved preoperative diagnosis with MRI.

Mosaicplasty With Autogenous Talar Autograft for Osteochondral Lesions of the Talus After Failed Primary Arthroscopic Management A Prospective Study With a 4-Year Follow-up

Background There have been limited data in the literature reporting the results of osteochondral autografting for osteochondral lesions of the talus that have failed arthroscopic treatment. Hypothesis Osteochondral autografting can produce significant clinical improvement and a high rate of healing of osteochondral defects of the talus that have failed arthroscopic treatment. Study Design Cohort study; Level of evidence, 4. Methods Between 1998 and 2003, 35 patients (18 men, 17 women) with osteochondral talar lesions for which arthroscopic excision, curettage, and drilling had failed, underwent mosaicplasty with an osteochondral graft harvested from the ipsilateral talar articular facet. A malleolar osteotomy or a tibial wedge osteotomy was used for central or posterior lesions that could not otherwise be reached. The mean age of the patients was 30.9 years, and the mean follow-up was 48.9 months. Results The American Orthopaedic Foot and Ankle Society Ankle Hindfoot scale score in patients without osteotomy rose by 39 points (P =. 0001); with malleolar osteotomy, by 30.1 points (P =. 017); with tibial wedge osteotomy, by 34.9 points (P =. 0002); and with the posterolateral approach, by 32 points. The Wilcoxon test revealed a significant difference between patients without and with osteotomy (P =. 027) and between patients with malleolar and tibial wedge osteotomies (P =. 046). There were no patients with nonunion or malunion in the osteotomy groups. The score values corresponded with the subjective patient evaluation. The Spearman coefficient of correlation was. 89. Conclusion Osteochondral autografting with tibial wedge osteotomy is a good alternative to malleolar osteotomy in osteochondral talar lesions that have failed arthroscopic treatment and that cannot be reached in spite of a forced plantar flexion of the ankle. Patients with small osteochondral lesions accessible through an anterior approach without additional osteotomy have the best prognostic factors.

New Technique for Cell-Seeded Collagen Matrix-Supported Autologous Chondrocyte Transplantation

Autologous chondrocyte transplantation/implantation (ACT/ACI) is becoming increasingly common for the treatment of large cartilage defects in the knee joint. The traditional ACT technique involves injection of a suspension of cells into the cartilage defect, which is covered with a periosteal flap or collagen membrane. The technique requires extensive suturing to create an effective seal; however, cell leakage remains a potential problem. Matrix-induced autologous chondrocyte implantation (MACI/MACT) avoids this potential problem by using a membrane on which chondrocytes are seeded and cultured for several days, before the membrane is cut to the correct size and shape of the defect. Time-consuming extensive suturing is unnecessary. However, cutting and repeated manipulation of the seeded membrane may result in the loss of critical chondrocytes. A modified technique termed ACT-collagen membrane seeding (ACT-Cs) has been developed in which expanded chondrocytes are applied to the collagen membrane after it has been cut to size, substantially reducing the risk of viable cell loss while retaining the ease and speed of the MACI/MACT procedure. In addition, the seeding of mitotically active chondrocytes onto the membrane after expansion and immediately before transplantation allows direct application of high cell concentrations.

Long-term Outcomes After First-Generation Autologous Chondrocyte Implantation for Cartilage Defects of the Knee

Background: Autologous chondrocyte implantation (ACI) represents an established surgical therapy for large cartilage defects of the knee joint. Although various studies report satisfying midterm results, little is known about long-term outcomes. Purpose: To evaluate long-term clinical and magnetic resonance imaging (MRI) outcomes after ACI. Study Design: Case series; Level of evidence, 4. Methods: Between January 1997 and June 2001, a total of 86 patients were treated with ACI for isolated cartilage defects of the knee. The mean patient age at the time of surgery was 33.3 ± 10.2 years, and the mean defect size was 6.5 ± 4.0 cm2. Thirty-four defects were located on the medial femoral condyle and 13 on the lateral femoral condyle, while 6 patients were treated for cartilage defects of the trochlear groove and 17 for patellar lesions. At a mean follow-up of 10.9 ± 1.1 years, 70 patients (follow-up rate, 82%) treated for 82 full-thickness cartilage defects of the knee were available for an evaluation of knee function using standard instruments, while 59 of these patients were additionally evaluated by 1.5-T MRI to quantify the magnetic resonance observation of cartilage repair tissue (MOCART) score. Clinical function at follow-up was assessed by means of the Lysholm score, the International Knee Documentation Committee (IKDC) score, and the Knee injury and Osteoarthritis Outcome Score (KOOS). Patient activity was assessed by the Tegner score. In addition, pain on a visual analog scale (VAS) and patient satisfaction were evaluated separately. Results: At follow-up, 77% reported being “satisfied” or “very satisfied.” The mean IKDC score at follow-up was 74.0 ± 17.3. The mean Lysholm score improved from 42.0 ± 22.5 before surgery to 71.0 ± 17.4 at follow-up (P < .01). The mean pain score on the VAS decreased from 7.2 ± 1.9 preoperatively to 2.1 ± 2.1 postoperatively. The mean MOCART score was 44.9 ± 23.6. Defect-associated bone marrow edema was found in 78% of the cases. Nevertheless, no correlation between the MOCART score and clinical outcome (IKDC score) could be found (Pearson coefficient, r = 0.173). Conclusion: First-generation ACI leads to satisfying clinical results in terms of patient satisfaction, reduction of pain, and improvement in knee function. Nevertheless, full restoration of knee function cannot be achieved. Although MRI reveals lesions in the majority of the cases and the overall MOCART score seems moderate, this could not be correlated with long-term clinical outcomes.

Articular and osseous lesions in recent ligament tears: arthroscopic changes compared with magnetic resonance imaging findings

The treatment of ligament injuries of the knee has undergone rapid progress, especially with the improvement of arthroscopic reconstruction of the anterior cruciate ligament (ACL). Since the advent of magnetic resonance imaging (MRI) after knee trauma with ligament injuries, interest has focussed on the clinical significance of concomitant articular and osseous lesions. In 48 of 141 MRIs, different types of these lesions were found; in 38 cases an arthroscopy was performed and 34 times the patients could clinically and radiologically be examined after at least 6 months. Bone bruise was found 26 times, in 16 cases associated with ACL-tears. Eleven patients had subchondral fractures, 7 osteochondral fractures, and in 4 patients, stress fractures were found. They were attributed to various mechanisms of trauma, in different percentages associated with ligament tears and in different dimensions visible or progressive on follow-up MRIs. Obviously some of the different lesions of subchondral and spongeous bone can indicate later degenerative arthritis, so that we find hints for a modification of rehabilitation, e.g., open versus closed kinetic chain or orthosis with relief of single compartments.

Autologous chondrocyte implantation (ACI) for the treatment of large and complex cartilage lesions of the knee

BackgroundComplex cartilage lesions of the knee including large cartilage defects, kissing lesions, and osteoarthritis (OA) represent a common problem in orthopaedic surgery and a challenging task for the orthopaedic surgeon. As there is only limited data, we performed a prospective clinical study to investigate the benefit of autologous chondrocyte implantation (ACI) for this demanding patient population.MethodsFifty-one patients displaying at least one of the criteria were included in the present retrospective study: (1.) defect size larger than 10 cm2; (2.) multiple lesions; (3.) kissing lesions, cartilage lesions Outerbridge grade III-IV, and/or (4.) mild/moderate osteoarthritis (OA). For outcome measurements, the International Cartilage Societys International Knee Documentation Committees (IKDC) questionnaire, as well as the Cincinnati, Tegner, Lysholm and Noyes scores were used. Radiographic evaluation for OA was done using the Kellgren score.Results and DiscussionPatients age was 36 years (13-61), defects size 7.25 (3-17.5) cm2, previous surgical procedures 1.94 (0-8), and follow-up 30 (12-63) months. Instruments for outcome measurement indicated significant improvement in activity, working ability, and sports. Mean ICRS grade improved from 3.8 preoperatively to grade 3 postoperatively, Tegner grade 1.4 enhanced to grade 3.39. The Cincinnati score enhanced from 25.65 to 66.33, the Lysholm score from 33.26 to 64.68, the Larson score from 43.59 to 79.31, and Noyes score from 12.5 to 46.67, representing an improvement from Cincinnati grade 3.65 to grade 2.1. Lysholm grade 4 improved to grade 3.33, and Larson grade 3.96 to 2.78 (Table 1), (p < 0.001). Patients with kissing cartilage lesions had similar results as patients with single cartilage lesions.Table 1Mean scores and grades at surgery (Tx) and at follow-upTxFollow-upScoreGradeScoreGradeICRS43Tegner13Noyes1347Cincinnati264662Lysholm334653Larson444793ConclusionOur results suggest that ACI provides mid-term results in patients with complex cartilage lesions of the knee. If long term results will confirm our findings, ACI may be a considered as a valuable tool for the treatment of complex cartilage lesions of the knee.

Comparison of Arthroscopic and Open Assessment of Size and Grade of Cartilage Defects of the Knee

PURPOSE The purpose of our study was to compare arthroscopic versus open measurement of cartilage defects and determination of defect grade according to the International Cartilage Repair Society (ICRS) classification. METHODS Arthroscopic determination of defect size and grade according to the ICRS classification of 450 focal cartilage defects in 407 patients who underwent autologous chondrocyte implantation was compared with definite findings at the time of open knee surgery. Results were analyzed based on defect location, defect size, and experience of the treating surgeon. RESULTS Open evaluation of all cartilage defects showed a mean size of 4.54 ± 2.11 cm², whereas arthroscopic determination resulted in a significantly larger mean defect size of 5.69 ± 1.81 cm² (P < .001, r = 0.757). This observation was found in all subgroups concerning defect location and experience of the treating surgeon (P < .001). Overestimation was pronounced among inexperienced surgeons (all P < .01) and in smaller defects (P < .01). Concerning grading of the defect according to the ICRS classification, there was a consensus in 80.9% of the cases when arthroscopic grading was compared with open grading. No differences were found based on defect location or experience of the treating surgeon (P > .05). CONCLUSIONS Although a high correlation was found between arthroscopic and open evaluation of the cartilage defect size, there is a significant overestimation of the cartilage defect size during arthroscopy. This observation is independent of defect location. Smaller defects and inexperienced surgeons are factors that make an overestimation of defect size more likely. Arthroscopic detection and estimation of the full-thickness cartilage defects according to the ICRS classification seem reliable. LEVEL OF EVIDENCE Level IV, therapeutic case series.

Clinical and cellbiological aspects of autologous chondrocytes transplantation

SummaryThe treatment of deep cartilage defects is a challenge for every orthopeadic surgeon. The potention for regeneration of cartilage tissue is minimal and leads to mechanically inferior fibrous tissue. The established techniques induce the growth of fibrous tissue but fail to prevent arthrosis. Autologous chondrocyte transplantation seems to be the most promising therapy concept with clinical relevance to reserves a full thickness cartilage defekt with hyaline-like cartilage. Outcome studies with a follow up from 2–10 years show in up to 90 % good and excellent results for defects on the femoral condyle and 70 % for the patella. Mechanical testing of the regenerated cartilage showed almost simular stiffness as nearly normal hyaline cartilage. The available data justify the acceptance of autologous chondrocyte transplantation as a standard procedure for limited indications and well-trained surgeons. Result of already inaugurated studies will show the potential of chondrocyte transplantation to prevent osteoarthritis.ZusammenfassungGelenkknorpeldefekte gelten als schwer zu therapieren. Die Regenerationspotenz des Knorpelgewebes ist gering und führt zur Bildung von mechanisch minderwertigem Faserknorpel. Die etablierten Behandlungsmethoden können zwar die Bildung von Faserknorpel induzieren, die Entstehung einer Arthrose jedoch nicht verhindern. Die autologe Chondrozytentransplantation (ACT) stellt gegenwärtig das vielversprechendste klinisch einsetzbare neue Verfahren dar, mit welchen ein dem hyalinen Gelenkknorpel sehr ähnliches Regeneratgewebe im Defektbereich gebildet werden kann. Die jetzt vorliegenden wissenschaftlichen Ergebnisse zeigen über einen Nachuntersuchungszeitraum von 2–10 Jahren zu 90 % gute und sehr gute klinische Ergebnisse bei Anwendung an der Femurkondyle und ca. 70 % gute und sehr gute Ergebnisse bei der Behandlung von patellaren Knorpelschäden. Die Festigkeit dieses Regenerats liegt mit Werten von 2,77 N sehr nahe an Werten für gesunden hyalinen Gelenkknorpel (3,08 N). Bei strenger Indikations-stellung rechtfertigen die vorliegenden mittelfristigen Ergebnisse bereits jetzt einen klinischen Einsatz an speziellen Zentren. Ob diese Methode die Entstehung einer Arthrose verhindern kann, müssen die langfristigen Ergebnisse zeigen.

Scientific Evidence Base for Cartilage Injury and Repair in the Athlete

Soccer players and athletes in high-impact sports are frequently affected by knee injuries. Injuries to the anterior cruciate ligament and menisci are frequently observed in soccer players and may increase the risk of developing an articular cartilage lesion. In high-level athletes, the overall prevalence of knee articular cartilage lesions has been reported to be 36% to 38%. The treatment for athletic patients with articular cartilage lesions is often challenging because of the high demands placed on the repair tissue by impact sports. Cartilage defects in athletes can be treated with microfracture, osteochondral grafting, and autologous chondrocyte implantation. There is increasing scientific evidence for cartilage repair in athletes, with more extensive information available for microfracture and autologous chondrocyte implantation than for osteochondral grafting. The reported rates and times to return to sport at the preinjury level are variable in recreational players, with the best results seen in younger and high-level athletes. Better return to sport is consistently observed for all repair techniques with early cartilage repair. Besides minimizing sensorimotor deficits and addressing accompanying pathologies, the quality of the repair tissue may be a significant factor for the return to sport.