REGENERATION OF MENISCAL CARTILAGE WITH USE OF A COLLAGEN SCAFFOLD - ANALYSIS OF PRELIMINARY DATA

A collagen scaffold was designed for use as a template for the regener ation of meniscal cartilage and was tested in ten patients in an initi al, Food and Drug Administration-approved, clinical feasibility trial, The goal of the study was to evaluate the implantability and safety o f the scaffold as well as its ability to support tissue ingrowth. The study was based on the findings of in vitro and in vivo investigations in dogs that had demonstrated cellular ingrowth and tissue regenerati on through the scaffold, Nine patients remained in the study for at le ast thirty-six months, and one patient voluntarily withdrew after thre e months for personal reasons, The collagen scaffold was found to be i mplantable and to be safe over the three-gear period, Histologically, it supported regeneration of tissue in meniscal defects of various siz es, No adverse immunological reactions were noted on sequential serolo gical testing, On second-look arthroscopy, performed either three or s is months after implantation, gross and histological evaluation reveal ed newly formed tissue replacing the implant as it was resorbed, At th irty-sir months, the nine patients reported a decrease in the symptoms , According to a scale that assigned 1 point for strenuous activity an d 5 points for an inability to perform sports activity, the average sc ore was 1.5 points before the injury; 3.0 points after the injury and before the operation, and 2.4 points at sis months postoperatively, 2. 2 points at twelve months, 2.0 points at twenty-four months, and 1.9 p oints at thirty-sis months, According to a scale that assigned 0 point s for no pain and 3 points for severe pain, the average pain score was 2.2 points preoperatively and 0.6 point thirty-sis months postoperati vely. One patient, who had had a repair of a bucket-handle tear of the medial meniscus and augmentation with the collagen scaffold, had rete aring of the cartilage nineteen months after implantation. Another pat ient had debridement because of an irregular area of regeneration at t he scaffold-meniscus interface twenty-one months after implantation, M agnetic resonance imaging scans demonstrated progressive maturation of the signal within the regenerated meniscus at three, six, twelve, and thirty-six months, These findings suggest that regeneration of menisc al cartilage through a collagen scaffold is possible, Additional studi es are needed to determine longterm efficacy.