Sporting Activity Is Reduced 11 Years After First-Generation Autologous Chondrocyte Implantation in the Knee Joint.

BACKGROUND: Little is known about long-term sporting activity after periosteal autologous chondrocyte implantation (ACI-P) and its correlation to clinical, morphological, and ultrastructural cartilage characteristics on magnetic resonance imaging (MRI). PURPOSE: To evaluate long-term sporting activity after ACI-P and to correlate with clinical and MRI findings. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Patients who underwent ACI-P for isolated cartilage defects of the knee joint between 1997 and 2001 were analyzed for sporting ability for 3 different time points: lifetime until the onset of pain, the year before ACI-P, and 11 years (range, 9.0-13.4 years) postoperatively. Sporting activity was assessed and patients' level of activity scaled using standardized questionnaires. MRI scans of the affected knee joint at follow-up were analyzed using the MOCART (magnetic resonance observation of cartilage repair tissue) score and T2 mapping. RESULTS: Seventy of 86 patients (81% follow-up rate) consisting of 25 female and 45 male patients, with a mean age of 33.3 ± 10.2 years at the time of surgery, mean defect size of 6.5 ± 4.0 cm2, and 1.17 treated defects per patient, agreed to participate in the study at a mean 10.9 ± 1.1 years after ACI-P. Fifty-nine patients (69% of total; 84% of follow-up) agreed to MRI, allowing the complete evaluation of 71 transplant sites. Before the onset of symptoms (lifetime), 95.7% of patients played a mean 6.0 sporting activities at a competitive level. In the year before ACI-P, 81.4% of patients played a mean 3.4 sporting activities in 2.4 sessions during 5.4 hours per week at a recreational level. At follow-up, 82.9% of the patients played a mean 3.0 sporting activities in 1.8 sessions during 3.0 hours per week at a recreational level. In contrast to objective factors, 65.6% of the patients felt that their subjective sporting ability had improved or strongly improved after ACI-P, whereas 12.9% felt that their situation had declined or strongly declined, and 21.4% stated that their sporting ability had undergone no change because of surgery. Factors of sporting activity correlated significantly with clinical long-term outcomes. MRI analysis with a mean repair tissue T2 relaxation time of 35.2 milliseconds and mean MOCART score of 44.9 showed no conclusive significant correlation to sporting activity. Level of performance was the only sporting activity factor to show a weak correlation with subgroups of the MOCART score. CONCLUSION: The premorbid level of sporting and recreational activities cannot be achieved 11 years after ACI-P. The MRI results determined at this time point did not conclusively correlate with long-term sporting activity.

Return to Sports Activity and Work After Autologous Chondrocyte Implantation of the Knee: Which Factors Influence Outcomes?

BACKGROUND: Autologous chondrocyte implantation (ACI) has been associated with satisfying results in everyday activities. Clinical results after ACI treatment of femorotibial lesions are superior in comparison with patellofemoral lesions. There is limited information regarding at which level recreational, amateur, and professional athletes can resume sports and physical activities as well as work after ACI and what parameters influence return to work and sports. HYPOTHESIS: Return to sports activity and work is dependent on defect characteristics such as location and size. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 130 patients with isolated full-thickness cartilage defects of the knee joint treated with ACI between June 2000 and October 2007 were retrospectively studied by an established questionnaire that assessed sports-specific questions such as frequency, duration, and intensity. Engagement in 32 different sports disciplines was evaluated. In addition, work-specific data were evaluated according to classifications established by the REFA Association. Results were evaluated depending on patient- and defect-specific parameters. RESULTS: The mean ± SD patient age at ACI was 36.2 ± 9.2 years, with a mean defect size of 4.4 ± 1.7 cm(2). Defects were located at the femorotibial compartment in 55.7% of cases, whereas lesions of the patellofemoral compartment were found in 44.3%. Mean duration of inability to work after ACI was 13.6 ± 11.0 weeks and did not appear to be influenced by patient age. Defect location and defect size did not appear to significantly influence return-to-work rates, but work intensity before surgery significantly influenced return-to-work rates and duration of absence from work. Workplace adaptations were necessary in only 9.2% of cases postoperatively. With regard to postoperative sports activity, 73.1% of patients were able to return to sports. Neither defect location nor size significantly influenced return to physical activity. Patients participated in a mean of 2.3 different sports during their lifetime. Both duration of exercise and number of sessions per week significantly decreased from before to after surgery. Detailed analysis of 32 different sporting activities revealed that high-impact as well as start-stop sports were generally abandoned in favor of endurance and low-intensity exercises. A lifetime level of competitiveness was maintained in 31.3% of cases, while return to elite sports at the time of the survey became highly unlikely (0.8%). CONCLUSION: The study results illustrate that treatment of articular cartilage defects of the knee joint leads to satisfactory results concerning everyday activities. With the exception of physical labor, no essential adaptations needed to be made at work. Regarding sports activity, return to low- and moderate-intensity levels appears realistic in the majority of cases, whereas the likelihood of returning to activities with high stress applied on the knee joint is low. Neither defect location nor size appears to significantly influence postoperative sports activity or return-to-work rates.

Long-term T2 and Qualitative MRI Morphology After First-Generation Knee Autologous Chondrocyte Implantation: Cartilage Ultrastructure Is Not Correlated to Clinical or Qualitative MRI Outcome.

BACKGROUND: There are several reports on long-term clinical outcomes after autologous chondrocyte implantation (ACI) for knee cartilage defect treatment. Few published articles have evaluated defect quality using quantitative magnetic resonance (MR) imaging techniques. PURPOSE: To evaluate clinical outcomes and the quality of repair tissue (RT) after first-generation periosteum-covered ACI (ACI-P) using qualitative MR outcomes and T2-weighted relaxation times. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: All patients (n = 86) who underwent knee joint ACI-P (from 1997 through 2001) with a postoperative follow-up of at least 10 years were invited for clinical and MR evaluation. Clinical outcomes analysis included pre- and postoperative Lysholm and numeric analog scale (NAS) for pain (10 = worst, 0 = best). Radiographic analysis included postoperative T2-weighted mapping of the RT, RT-associated regions, and healthy control cartilage; MOCART (magnetic resonance observation of cartilage repair tissue) score; a modified Knee Osteoarthritis Scoring System (mKOSS; 0 = best, 15 = worst) score; as well as numeric grading for subjective RT and whole knee joint evaluation (1 = best, 6 = worst). RESULTS: A total of 70 patients (45 male, 25 female; mean age, 33.3 ± 10.2 years; 81% follow-up rate) with 82 defects were available for follow-up at an average 10.9 ± 1.1 years postoperatively, with MR analysis for 59 patients with 71 transplant sites (average defect size, 6.5 ± 4.0 cm(2)). Final Lysholm (71.0 ± 17.4) and NAS (7.2 ± 1.9) scores improved significantly when compared with preoperative scores (Lysholm: 42.0 ± 22.5; NAS: 2.1 ± 2.1; P < .01 for both). Average transplant T2 was 35.2 ± 11.3 ms and thereby significantly lower (P = .005) when compared to the intraknee healthy femur T2 (39.7 ± 6.8 ms). The MOCART was 44.9 ± 23.6 and mKOSS was 4.8 ± 3.2. RT subjective grading was 3.3 ± 1.4, while it was 2.3 ± 0.7 for whole joint evaluation. The RT T2 significantly correlated with postoperative NAS (P = .04; r = -0.28); it also correlated with the healthy femur T2 (P = .004; r = 0.4). The MOCART significantly correlated with the mKOSS (P < .001). CONCLUSION: The MRI outcome is imperfect in this collective of patients. There is only weak correlation of quantitative imaging data and clinical function. Qualitative imaging data are much better correlated to functional outcomes.

First-generation versus second-generation autologous chondrocyte implantation for treatment of cartilage defects of the knee: a matched-pair analysis on long-term clinical outcome.

PURPOSE: Since the introduction of autologous chondrocyte implantation (ACI) for the treatment of cartilage defects, the initial technique has undergone several modifications. Whereas an autologous periosteum flap was used for defect coverage in first generation ACI, a standardized collagen membrane was utilized in second generation ACI. To date, however, no study has proven the superiority of this modification in terms of long-term clinical outcome. The purpose of this matched-pair analysis was therefore to compare the clinical long-term outcome of first and second generation ACI with a minimum follow-up of ten years. METHODS: A total of 23 patients treated with second generation ACI for isolated cartilage defects of the knee were evaluated after a minimum follow-up of ten years using Lysholm and IKDC scores. The results of these patients were compared to those of 23 matched patients treated with first generation ACI. Pair wise matching was performed by defect location, patient age, and defect size. RESULTS: While all patient characteristics such as age (31.7 years SD 6.9 vs. 31.4 years SD 7.8), defect size (5.1 cm² SD 2.3 vs. 4.9 cm² SD 1.5), and follow-up time (10.7 months SD 1.0 vs. 10.5 months SD 0.6) were distributed homogenously in both treatment groups, significant better Lysholm (82.7 SD 9.9 versus 75.6 SD 11.8; p = 0.031) and IKDC scores (76.4 SD 12.8 versus 68.0 SD 12.0, p = 0.023) were found in the group of patients treated with second generation ACI compared to those treated with first generation ACI. In both groups, four patients (17.4%) received surgical reintervention during follow-up. CONCLUSIONS: The use of a collagen membrane in combination with autologous chondrocytes (second generation ACI) leads to superior clinical long-term outcome compared to first generation ACI. Based on these results, second generation ACI should be preferred over first generation ACI.

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 cm(2). 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.

What Patients Expect About Autologous Chondrocyte Implantation (ACI) for Treatment of Cartilage Defects at the Knee Joint.

OBJECTIVE: Although autologous chondrocyte implantation (ACI) has become an established surgical treatment for cartilage defects of the knee, little is known about what patients expect about this surgery. DESIGN: A total of 150 patients who underwent ACI for cartilage defects at the knee were assigned to the present study and asked about their expectations and estimation concerning the ACI procedure. Patients were asked to answer 4 questions of a web-based questionnaire concerning their expectations on clinical outcome and on factors they considered relevant for clinical outcome. RESULTS: A total of 118 (79%) returned questionnaires. Mean patient age was 32.6 years and mean defects size was 4.1 cm(2). A proportion of 70% (n = 83) of patients expected pain-free sports participation as a result of the ACI surgery, including 24 patients who expected to return to high-impact sports without any restrictions. Only 12.7% expected a reduction but persistence of pain during everyday activities. Concerning factors that influence outcome, the majority of the patients (55.1%) considered defect characteristics (i.e., size and location) most important for clinical outcome, whereas only a small proportion of patients considered rehabilitation (7.6%), cell quality (10.2%), or prior surgeries (4.2%) more relevant for final outcome. CONCLUSION: The present study illustrates that expectations of ACI patients are demanding and quite high. The ACI technique seems generally considered to be able to restore pain-free sports participation. Patients do not seem to be aware of all factors of possible importance concerning clinical outcome.