Systematic evaluation of acute knee injuries.

The high percentage of significant injury associated with a hemarthrosis correlates with the findings of Noyes, DeHaven, and others. The development of significant knee swelling immediately after injury should be an alarming sign. Our study revealed a significant probability of anterior cruciate ligament tear or meniscal tear in the acute hemarthrosis. Arthroscopy in acute hemarthrosis certainly should be considered and, in many cases, performed. Although not within the scope of this article, acute arthroscopic repair of a torn meniscus, evaluation of the degree of tear of the anterior cruciate ligament, and arthroscopic repair of osteochondral fractures are all benefited by acute arthroscopic examination. Decisions in diagnosis are helped by the knee aspiration.