In Defence of the Meniscus

The advent of arthrography and arthroscopy have highlighted the difficulties of diagnosing meniscal lesions. Much of the success with these time-consuming techniques appears to have been in North America. At the moment it is likely that only a minority of British surgeons will acquire that expertise with arthroscopy described by Jackson and Dandy (1976). Indeed it is probable, in the current economic climate, that many will not even be able to acquire an arthroscope (Lancet 1976). Not all practitioners of arthrography (DeHaven and Collins 1 975 ; Axer et al. 1 976) report the success rate of over 90 per cent described by those North American authors who have become particularly expert with the technique (Nicholas, Freiberger and Killoran 1970; McBeath and Wirka 1972; Kaye and Freiberger 1975). The potential weakness of both techniques is in demonstrating the posterior third of the meniscus and it is here, where tears are most common, that false positive results and false negatives occur. Although the best compromise may be to depend upon a combination of clinical diagnosis, arthrography and arthroscopy, the surgeon first has to exercise clinical judgement in selecting patients for either investigation. This can only be based upon clinical features, which, despite being familiar, have previously not been prospectively and statistically assessed in terms of their diagnostic reliability. Despite arthrography or arthroscopy the situation will arise wherein the knee is opened and no tear is obvious. It is then that Watson-Jones’ (1956) teaching that the cartilage should be removed for fear of leaving a posterior tear, invisible from the front, becomes a real threat to the meniscus. One has to balance the risks of leaving such a tear against those of excising a normal meniscus. No surgeon can escape this dilemma. MATERIAL AND METHODS