BST-CarGel® Treatment Maintains Cartilage Repair Superiority over Microfracture at 5 Years in a Multicenter Randomized Controlled Trial

Abstract

ObjectiveThe efficacy and safety of BST-CarGel®, a chitosan scaffold for cartilage repair was compared with microfracture alone at 1 year during a multicenter randomized controlled trial in the knee. This report was undertaken to investigate 5-year structural and clinical outcomes.DesignThe international randomized controlled trial enrolled 80 patients, aged 18 to 55 years, with grade III or IV focal lesions on the femoral condyles. Patients were randomized to receive BST-CarGel® treatment or microfracture alone, and followed standardized 12-week rehabilitation. Co-primary endpoints of repair tissue quantity and quality were evaluated by 3-dimensional MRI quantification of the degree of lesion filling (%) and T2 relaxation times. Secondary endpoints were clinical benefit measured with WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) questionnaires and safety. General estimating equations were used for longitudinal statistical analysis of repeated measures.ResultsBlinded MRI analysis demonstrated that BST-CarGel®-treated patients showed a significantly greater treatment effect for lesion filling (P = 0.017) over 5 years compared with microfracture alone. A significantly greater treatment effect for BST-CarGel® was also found for repair tissue T2 relaxation times (P = 0.026), which were closer to native cartilage compared to the microfracture group. BST-CarGel® and microfracture groups showed highly significant improvement at 5 years from pretreatment baseline for each WOMAC subscale (P < 0.0001), and there were no differences between the treatment groups. Safety was comparable for both groups.ConclusionsBST-CarGel® was shown to be an effective mid-term cartilage repair treatment. At 5 years, BST-CarGel® treatment resulted in sustained and significantly superior repair tissue quantity and quality over microfracture alone. Clinical benefit following BST-CarGel® and microfracture treatment were highly significant over baseline levels.

Single-step scaffold-based cartilage repair in the knee: A systematic review

“…1). Two were randomised controlled trials 1 (RCTs) [15][16][17] and one was a nonrandomised controlled trial (non-RCT) 18 ; with a total of 136 patients (84 in the scaffold and 52 in the control groups). All three studies assessed the clinical effectiveness and safety of…”

“…Nevertheless, in none of the studies the improvement in the scaffold groups was significantly better than in the control groups. [15][16][17][18] …”

“…[15][16][17][18] In one RCT with 38 patients and in two scaffold groups (one group received a glued, the other group a sutured scaffold), the joint functionality was measured with the Modified Cincinnati score (scale: 6-100) and with (a modified) ICRS score (International Cartilage Repair Society). The Modified Cincinnati Score increased in all study groups over time.…”

“…However, the difference in changes of the scores between the study groups was statistically not significant. 16,17 In the identified non-RCT, the severity and frequency of pain were measured. However, it was not stated on which scale or scoring system the measurement was based on.…”

“…However, both study groups showed significant improvement from baseline in both subscales. 16,17 In the non-RCT, joint functionality was measured with the IKDC Score (International Knee Documentation Committee, scale: 0-100). However, it was only stated that the score improved over time in both study groups, whereas the differences of the score changes between the study groups were statistically not significant after 3 and 6 months of follow-up.…”