New methods in arthroscopy: preliminary investigations.

The microhysteroscope, which affords direct in vivo observation of otherwise inaccessible surfaces, can be used to great advantage in arthroscopy. Although conventional arthroscopy can distinguish between 'inflammatory' and 'reactive' (post-traumatic) synovial changes, the microendoscope offers the possibility of more precise differentiation. Synovial membranes, joint cartilage, and menisci were studied at four different magnifications, including microscopic observation of vitally stained cells. Frankly pathological synovia (e.g., rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis) were compared and distinguished from examples of less florid synovial changes. The fibrocartilaginous structure of the menisci and secondary undulations and tertiary depression of joint cartilage become visible in vivo with the microendoscope; these may well point to early damage to these structures. The authors believe that the three dimensional images at the magnifications provided by this microendoscope go some way towards bridging the gap between the conventional arthroscope, the light microscope, and the scanning electron microscope. This report presents preliminary findings with this new technique.