An organ culture model for assaying wound repair of the fibrocartilaginous knee joint meniscus.

We describe an in vitro organ culture system that can be used to test the effect of various substances and compounds on the wound healing process in the fibrocartilaginous substance of the knee joint meniscus. Using culture medium containing either 10% fetal bovine serum (FBS) or our recently developed serum-free, defined culture medium (DM), we have demonstrated the ability of meniscal fibrochondrocytes from intact rabbit menisci to extricate themselves from their surrounding matrix and migrate into an exogenous, purified fibrin clot in vitro. After 4 weeks of culture in FBS-containing medium, the cells which had invaded the clot had initiated the early aspects of a typical reparative response; the same response did not occur in DM alone. Morphologically, the cells on the surface of the clot resembled the original superficial fibrochondrocytes, whereas those cells within the substance of the clot more closely resembled the original deep fibrochondrocytes. After 10 weeks, the reparative response had progressed only to a certain point and then failed to progress further under these culture conditions. However, use of this culture system should now make it possible to rapidly identify and quantitate those factors which would most likely be useful in continuing the reparative response and in affecting meniscal wound repair. Elucidation of the mechanisms and requirements for meniscal healing will eventually allow the practicing orthopaedic surgeon to effect in situ meniscal repair and obviate the need for meniscectomy and its morbid sequelae.

Discoid lateral meniscus in a young child: case report and review of the literature.

Management of discoid lateral meniscus in a 6-month-old child is discussed. The patient presented with a lateral knee mass and an associated popping sound of the joint during flexion and extension. The diagnosis, which the authors believe to be the youngest presentation of this entity, was confirmed by arthrography. Computed tomographic features and magnetic resonance images of the discoid meniscus are presented. Management and theories of etiology of the discoid lateral meniscus are discussed.

Minimal internal and external fixation in the treatment of open tibial fractures.

The advantages of rigid internal fixation for open tibial fractures are well documented. There is also a large literature describing various forms of external fixation for open tibial shaft fractures. Because of the enthusiasm for internal and external fixation, the disadvantages and complications warrant new emphasis.