Findings at arthroscopy and arthrography in knee injuries.

The diagnostic accuracy of arthroscopy and arthrography was investigated. A total of 135 patients were examined by the two methods. All were operated on and 90 of them were analyzed in detail, the X-ray examinations being done at this hospital. In 82 patients arthroscopy gave correct information. In eight (9 per cent) the diagnosis was incorrect, in most cases a rupture of the posterior horn of the medial meniscus being overlooked. Arthrography gave accurate preoperative information in 52 patients, but in 38 (42 per cent) the diagnosis was inaccurate. This difference in correlation with the operation findings between arthroscopy and arthrography was highly significant (P less than 0.001), and it is concluded that endoscopy gives more complete and more useful preoperative information than arthrography. Arthrography, however, remains a valuable diagnostic tool, as arthroscopy cannot be performed in every patient with knee symptoms.