Repair of Extensor Mechanism Injuries

Abstract

In most sports the extensor mechanism of the knee is repeatedly stressed. Some athletes will develop an inflammatory response from the accumulation of microtrauma, which can be concentrated at either the superior or inferior pole of the patella. This symptom complex has been well classified by Blazina and co-workers into several phases of jumper’s knee.¹ Several studies have demonstrated the histological findings of tendon degeneration from the repeated microtrauma.^1–3 This process can remain localized to the attachments at either pole of the patella, as described by Phases 1 through 3 in Blazina’s classification, or it can proceed to tendon failure in one catastrophic event.