Meniscus transplantation in the rabbit knee joint using a deep frozen meniscus allograft-pathohistologi- cal picture

Abstract

The aim of the study was to assess the clinical, radiological and histological characteristics of deep frozen meniscal allograft for the rabbit knee. Eighteen (18) New Zealand white rabbits were operated on both knees and evaluated at three time intervals: after 2 weeks (first group), 8 weeks (second group) and 36 weeks (third group). Left knees without meniscal transplantation, served as the controls. Meniscal grafts obtained from other rabbits were stored in a deep freeze at -17 °C when required deep frozen menisci were thawed in sterile saline and transplanted in the place of the removed right medial meniscus of the experimental animal. The general condition, operated knees and X-ray pictures were monitored. After sacrifice the meniscal allografts were histologically analyzed. There were no adverse clinical and radiological pathological findings after transplantation, while in the control group changes were noted. At histological evaluation, 2 weeks after transplantation the collagen fibers were not oriented and there was a low cell population. Vascularity was observed in the second group, with cell repopulation and young immature collagen fibers. In the third group at 36 weeks the collagen tissue was more mature, with significant cell repopulation. We may conclude that deep frozen meniscal allografts show significant collagen remodeling and cellular repopulation. New menisci protect the underlying cartilage. Thus this procedure appears beneficial in cases where there is no possibility to reconstruct the meniscal lesion.

Cilj ovog istraživanja je bio da se klinički, radiološki i histološki procene karakteristike duboko zamrznutog transplantata menuskusa na kolenu kunića. Ukupno je operisano osamnaest kunića, soja New Zeland i posmatrano u tri vremenske grupe: posle 2 nedelje (prva grupa), 8 nedelja (druga grupa) i posle 36 nedelja (treća grupa). Stanje životinje i operisanog kolena je praćeno klinički i radiološki, a po žrtvovanju je izvršena patohistološka analiza. Kod operisanih životinja, nije bilo kliničkih i radioloških promena za razliku od kontrolne grupe. Na histološkoj proceni meniskusa, u prvoj grupi (posle 2 nedelje) kolagena vlakna su bila neorijentisana sa izraženom ćelijskom depopulacijom, dok su posle 36 nedelja kolagena vlakna bila zrelija, sa značajnom ćelijskom repopulacijom. Duboko zamrznuti meniskalni alograft pokazuje značajnu kolagenu remodelaciju i ćelijski oporavak a novi meniskus je štitio hrskavicu zgloba. Zbog toga je primena duboko zamrznutog alografta meniskusa opravdana u slučajevima gde nije moguće očuvati povređeni meniskus.