Johan Vanlauwe

Long-term Subjective, Clinical, and Radiographic Outcome Evaluation of Meniscal Allograft Transplantation in the Knee

Background: Although meniscal allograft transplantation (MAT) has been performed for nearly 30 years, there are few long-term published studies of the technique. Hypothesis/Purpose: The goal of this study was to report the long-term results of a patient cohort whose medium-term results have been reported and to evaluate whether the results are maintained in the long term or deteriorate after a certain period. The hypothesis was that the subjective, clinical, and radiographic results are consistent in the long term without significant deterioration. Study Design: Case series; Level of evidence, 4. Methods: Thirty patients from the original cohort of 49 patients (50 MATs) who underwent MAT at least 9 years before this study were evaluated with the Knee injury and Osteoarthritis Outcome Score (KOOS); Lysholm, Tegner, and Short Form–36 scores; and a visual analog score for pain. A standardized clinical examination was performed to objectively evaluate knee-related symptoms. Standard weightbearing radiographs, including a full-leg standing radiograph, were performed to evaluate joint space narrowing and any progression of osteoarthritis and malalignment. These results, at a mean follow-up time of 12 years and 8 months (152 months; range, 112-216 months), were compared with the preoperative data and the outcome results at medium-term follow-up (mean, 8 years and 9 months). Results: Of the original 49 patients, 6 (12.2%) required conversion to a total knee arthroplasty during the study period and were considered failures, and 17 (34.7%) required a second surgical procedure during the study period. Excluding the 6 total knee arthroplasty cases, 90% of patients reported being very satisfied or satisfied and would undergo the procedure again. Only 1 patient reported not wanting to undergo the procedure again. Results of the visual analog score, KOOS and all KOOS subscales, Lysholm, and Short Form–36 all showed a statistically significant improvement at estimated follow-up periods of 7.5 and 12.5 years compared with preoperative scores. There was no statistically significant difference for these scores between 7.5 and 12.5 years postoperatively. Despite the improvement in outcome scores, the Tegner activity level score remained unchanged during the entire follow-up period. Regarding radiographic outcomes, there was a progressive increase in the Kellgren-Lawrence rating over the study period. There was a statistically significant (P = .0208) progressive joint space narrowing between estimates at the 7.5-year (5.45 mm) and 12.5-year (4.95 mm) follow-up. However, there was no statistically significant (P = .6724) difference in absolute value of alignment deviation from the 0° mechanical axis between 7.5 years (2.32°) and 12.5 years (2.51°) postoperatively. There was no difference between medial and lateral transplants. Conclusion: Despite an increase in joint space narrowing, MAT resulted in significant improvements in pain and functional outcomes over the study period. There was no change in these improvements between the medium- and long-term follow-up period. This study confirms the good and consistent results found in the literature concerning satisfaction, pain resolution, and functional scores at long-term follow-up.

Bicruciate retaining TKA: The future?

There is a general consensus amongst knee surgeons that the cruciate ligaments have an important role in the function and kinematics of the normal knee.

29.4 Comparison of structural repair following characterized chondrocyte implantation or microfracture for the treatment of symptomatic cartilage defects of the knee

Purpose: This study compared the efficacy and safety of Characterized Chondrocyte Implantation (CCI) to microfracture in the repair of symptomatic cartilage defects of the femoral condyle. Methods: CCI (n=51) was compared to microfracture (n=61) in patients with grade III–IV symptomatic cartilage defects of the femoral condyles in a prospective, multicenter, randomized, controlled trial. Structural repair was assessed at 1 year by histopathologists blinded to the treatment using computerized histomorphometry and an overall histology assessment. Clinical outcome was measured using the Knee Injury and Osteoarthritis Outcome Score (KOOS). Safety was recorded throughout the study. Results: CCI resulted in better structural repair than microfracture at 1 year post-treatment, as assessed by histomorphometry (p=0.003) and overall histology (p=0.012). Structural repair parameters relating to chondrocyte phenotype and tissue structure were also superior with CCI. Noninferiority of CCI was demonstrated for clinical outcome at 12–18 months, and both treatments were generally well tolerated. Conclusion: At 1 year post-treatment, CCI resulted in superior tissue repair compared to microfracture. Short-term clinical outcome after 12–18 months was similar for both treatments, as was the safety profile. The superior structural repair achieved with CCI may lead to improved long-term clinical benefits.

P48 Characterized chondrocyte implantation has a similar safety profile to microfracture forthe treatment of symptomatic cartilage defects of the knee

Purpose: As a one-step surgical procedure, microfracture is frequently considered to be technically easier and associated with less postoperative morbidity than autologous chondrocyte implantation (ACI), which involves both arthrotomy and arthroscopy and therefore safety was assessed in patients with symptomatic cartilage lesions of the knee treated with characterized chondrocyte implantation (CCI) or microfracture. Methods: CCI (n=57) was compared to microfracture (n=61) in patients with grade III–IV symptomatic cartilage defects of the femoral condyles in a Phase III, prospective, multi-center, randomized, controlled trial. Safety assessments included adverse events (AEs), physical examination, vital signs, hematology and clinical chemistry. Results: At 18 months post-surgery, similar proportions of patients experienced AEs in the CCI (88%) and microfracture (82%) groups; 67% and 59%, respectively, experienced AEs considered treatment related. The AE profile was generally similar between groups, with no significant difference for hypertrophy, although significantly more CCI-treated patients had joint swelling (19% versus 4.9%; p=0.022) and treatment-related joint crepitation (12% versus 1.6%; p=0.028). Although the proportion of patients with severe AEs was similar for CCI (12%) and microfracture (13%), slightly more microfracture-treated patients experienced serious (life-threatening or requiring hospitalization) AEs (13% versus 8.8%). No patients discontinued due to AEs or died during the study. Conclusion: Contrary to general opinion, the two-step CCI procedure, involving arthroscopy followed by arthrotomy, has a similar safety profile to that of microfracture, a one-step arthroscopic procedure, for treating cartilage lesions of the knee.