Experimental Osteoarthritis in the Rabbit

Abstract

Based on an experimental model of osteoarthritis in 42 full-grown rabbits the histological changes were studied during the development of osteoarthritis after operative induction of instability of the knee joint. The changes were followed from 2 week to 1½ years after the induction.

The first changes were observed at 1 week stage as a proliferation of the lining cells. During the time of observation additional changes were seen such as hypertrophy of villi, infiltrations with plasma cells and lymphocytes, increased vascularity and interstitial edema and fibrosis. Edema was only seen during the first months, later increasing fibrosis was predominant.

The first cartilage change was reduction of the staining ability, expressing depletion of GAG, this was seen already at the one week stage whereas morphological changes were present after 4–6 weeks.

It was concluded that the synovial membrane in this model shows changes that may contribute to the development of osteoarthritis.

Sammendrag

Der redegøres for de histologiske forandringer i synovialmembranen under udviklingen af eksperimentel osteoarthritis i knæleddet hos 42 udvoksede kaniner efter en instabilitetsoperation. De histologiske forandringer blev fulgt fra 1 uge til 1½ år efter operationen.

De første forandringer, der blev iagttaget en uge efter operationen, var en proliferation af synoviocytterne. I løbet af forsøgsperioden observeredes yderligere forandringer med hypertrofi af villi, infiltration med plasmaceller og lymfocytter, øget vaskularitet, ødem og fibrose. Ødem blev kun iagttaget i de første måneder, i de senere stadier dominerede en fremadskridende fibrose.

På et uges stadiet blev der iagttaget nedsat farvbarhed af brusken som udtryk for depletering af GAG. Morfologiske forandringer blev først iagttaget efter 4–6 uger.

Det konkluderes, at Synovialmembranen i denne model udviser forandringer, som kan være medvirkende årsag ved udviklingen af osteoarthritis.