Summary

The defect in meniscal subluxation usually occurs at the mensco-capsular junction, where a deficiency allows a hypermobile meniscus, which is not necessarily associated with a meniscal injury

Abstract

Subluxation of a healthy lateral meniscus, due to meniscal capsular disinsertion, is an uncommon cause of pain and locking knee. There is few literature reported so far. We present a case series of twelve patients, in which the diagnosis was made by clinical presentation and physical examination, locking knee episodes and recurrent pain. In all cases the MRI reported no pathological findings. Final diagnosis was made arthroscopically, where we found a posterior meniscal capsular disinsertion, with subluxation or hypermobility of the posterior horn of the lateral meniscus. Meniscal fixation was made in all patients, combining all-inside and vertical outside-in sutures, achieving a stable meniscus. All patients where satisfied, presented no complaints and returned to their previous sports level between 4th and 6th month after surgery.
The posterior horn of the lateral meniscus is liable to subluxation given that it has a weak menisco-capsular junction and it is disrupted by de popliteus tendon. As the lateral meniscus is in situ when de MRI is performed, these report no pathological findings. This is the reason why a thorough physical examination must be realized and clinical findings, relieving MRI to find suspected associated injuries. Menisco-capsular repair has shown excellent outcomes, good healing rates, no relapses and asymptomatic return to competition.