[Autologous chondrocyte transplantation with bone augmentation for the treatment of osteochodral defects of the knee : Treatment of osteochondral defects of the femoral condyles using autologous cancellous bone from the iliac crest combined with matrix-guided autologous chondrocyte transplantation].

OBJECTIVE

Open treatment of osteochondral defects of the knee to fully restore the bony defect and the articular surface.

INDICATIONS: Focal, symptomatic osteochondral lesions of the knee with a depth of ≥ 5 mm and a surface of ≥ 1.5 cm2.

CONTRAINDICATIONS: Osteoarthritis, kissing lesions, age > 50 years, untreated ligament instability or relevant malalignment, insufficient containment, inflammatory joint disease.

SURGICAL TECHNIQUE: Two-step procedure: Step 1 (arthroscopy): evaluation of the defect, harvesting of cartilage tissue for chondrocyte cultivation, if needed treatment of concomitant pathologies. Step 2 (open surgery): arthrotomy, preparation of the defect, transfer of iliac crest cancellous bone plugs to the defect, preparation of the cartilage defect (can exceed the size of the bony defect), matrix-guided autologous chondrocyte transplantation.

POSTOPERATIVE MANAGEMENT: Step 1: therapy follows the needs of concomitant procedures, with early full weight bearing as tolerated. Step 2: no suction drain, knee brace in extension for week 1, followed by stepwise increase of flexion, partial weight bearing for 6 weeks, continuous passive motion starting on postoperative day 1.

RESULTS

Since 2018, 8 patients (mean age 29.4 years) have been treated with the described technique. All patients were available for follow-up examination after an average of 12 months. The KOOS (Knee injury and Osteoarthritis Outcome Score) improved from 45.8 to 81.3 and the postoperative X‑rays showed bony healing of the cancellous bone plugs in all patients. The MOCART (Magnetic Resonance Observation of Cartilage Repair Tissue) score reached 80.4 points.