Single-stage autologous chondrocyte coimplantation on a hyaluronan scaffold for the treatment of knee cartilage lesions: a case series of 16 patients with clinical outcomes up to 5 years

Introduction

The direct reimplantation of autologous primary articular chondrocytes in a single-stage procedure for knee cartilage lesions is a novel approach, yet to be extensively reported. This study aimed to evaluate the clinical outcomes and reinterventions over a 5-year period post-surgery.

Methods

A prospective case series involving 16 patients (4 female, 12 male) with single or multiple focal knee cartilage lesions was conducted. The mean age at baseline was 36.8 (±11.5) years. The mean total lesion size was 4.5 (±2.3) cm² Patients underwent surgery where articular chondrocytes and mononuclear bone marrow cells were isolated, mixed, and seeded onto a hyaluronan-based scaffold within the lesion. A structured physical therapy regimen was followed, and patients were assessed using Knee injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee (IKDC) Subjective questionnaires at various intervals. Overall, patient-reported outcomes improved over the first 3 years post-surgery, with slight declines thereafter.

Results

Significant improvements over baseline were noted for various KOOS parameters and IKDC Subjective scores at different follow-up points. Reinterventions were required for two patients, one receiving intra-articular injections with mesenchymal stromal cells and another undergoing knee washout for septic arthritis while a meniscus implant was removed. Patient satisfaction at final follow-up was generally favorable. Despite a significant intraoperative cell isolation time of approximately 1.5 hours, the procedure demonstrated safety and efficacy, with an average of ±0.9 million articular chondrocytes obtained per case.

Conclusions

This study underscores the potential of coimplantation of intraoperatively isolated articular chondrocytes and bone marrow cells on a hyaluronan scaffold as a promising strategy for treating symptomatic knee cartilage lesions.