A clinical feasibility study to evaluate the safety and efficacy of PEOT/PBT implants for human donor site filling during mosaicplasty.

UNLABELLED: Mosaicplasty has become a well-accepted treatment modality for articular cartilage lesions in the knee. Postoperative bleeding remains potentially concerning. This study evaluates the porous poly(ethylene oxide)terephthalate/poly(butylene terephthalate) (PEOT/PBT) implants used for donor site filling. Empty donor sites were the controls. After 9 months, MRI, macroscopical and histological analysis were carried out. Treated defects did not cause postoperative bleeding. No adverse events or inflammatory response was observed. PEOT/PBT implants were well integrated. Empty controls occasionally showed protrusion of repair tissue at the defect margins. Surface stiffness was minimally improved compared to controls. Existing polymer fragments indicated considerable biodegradation. Histological evaluation of the filled donor sites revealed congruent fibrocartilaginous surface repair with proteoglycan-rich domains and subchondral cancellous bone formation with interspersed fibrous tissue in all implanted sites. The PEOT/PBT implants successfully reduce donor site morbidity and postoperative bleeding after mosaicplasty. LEVEL OF EVIDENCE: II.

Autologous osteochondral mosaicplasty grafting.

Successful management of chondral and osteochondral defects of the weight-bearing joint surfaces has always been a challenge for orthopedic surgeons and rehabilitation specialists. Autologous osteochondral mosaic transplantation technique is one of the recently evolved methods to create hyaline or hyaline-like repair tissue in the pathologic area. Clinical evaluation, various imaging techniques, arthroscopy (second look), histological examination of biopsy samples, and measurements of cartilage mechanical properties are used to evaluate the merits of outcomes and quality of the transplanted cartilage. According to our investigations, good to excellent results were achieved in more than 92% of patients treated with femoral condylar implantations, 87% of those treated with tibial resurfacing, 79% of those treated with patellar and/or trochlear mosaicplasties, and 94% of those treated with talar procedures. Long-term donor-site discrepancies, assessed with use of the Bandi Score, showed that patients had 3% morbidity after mosaicplasty. Sixty-nine of 89 patients who were followed up with a second-look arthroscopy showed congruent gliding surfaces, histological evidence of the survival of the transplanted hyaline cartilage, and fibrocartilage filling of the donor sites. In a series of 831 consecutive patients, very few complications have been observed. These included 4 deep infections and 36 painful postoperative intra-articular bleedings. On the basis of these results and those of other similar studies, autologous osteochondral mosaicplasty appears to be a promising alternative for the treatment of small- and medium-sized focal chondral and osteochondral defects of the weight-bearing surfaces of the knee and other weight-bearing synovial joints.