Aim

Microbiological culture of intraoperative periprosthetic tissue samples (IPTS) is one of the main criteria in diagnosing prosthetic joint infections (PJI) as stated by different guidelines. The current techniques are labor-intensive, prone for contamination and show low sensitivity. The aim of this study was to evaluate the added value of beadmill processing of IPTS and culturing in blood culture bottles (BCBs) over the conventional method of standard agar and broth alone.

Purpose: Characterized chondrocyte implantation (CCI) uses an autologous cartilage cell population capable of making stable cartilage in vivo. Despite comparable short-term improvement after intervention, clinical follow-up was to determine long-term clinical benefit of CCI in the repair of full-thickness knee cartilage lesions.

Methods: In a randomized controlled clinical trial comparing CCI to microfracture, patients with single ICRS grade III/IV symptomatic defects of the femoral condyles were randomized to receive either treatment (n=57 vs. n=61, respectively). Clinical improvement was measured up to 36 months using the KOOS, Visual Analogue Scale for knee pain (VAS) and Activity Rating Scale (ARS). Treatment failures and safety were monitored throughout.

Results: At baseline, KOOS was comparable between treatment groups (Mean ± SD: CCI, 56.30 ± 13.61; microfracture, 59.53 ± 14.95); improvement from baseline in adjusted mean ± SE of the overall KOOS at 36 months was 21.25 ± 3.60 for the CCI group and 15.83 ± 3.48 for the microfracture group. In a mixed linear model (with LOCF imputation), significantly greater improvements were shown for CCI vs. microfracture in change from baseline in all KOOS domains (p-value for the Overall KOOS = 0.0007) except for ‘Sports’. Between-group improvements from baseline to month 36 in VAS and ARS scores were similar. For CCI and micro-fracture groups, the percentages of treatment responders (improvement of 10 percentage points or more) were 83% (n = 34 of 41) vs. 62% (n = 31 of 50) on the KOOS and 83% vs. 66% on the VAS. Time to treatment failure was not statistically significant between the groups (n CCI/MF = 7/9). There was no change in safety profiles in comparison to the previous recorded data.

Conclusions: The initial superior structural outcome with CCI after 12 months post-surgery was substantiated by superior clinical benefit at 36 months compared to microfracture.

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

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.