Clinical features of the posterior horn tear in the medial meniscus.
BACKGROUND
A lower threshold of suspicion is necessary for the appropriate diagnosis of a posterior horn tear in the medial meniscus. In these cases, radial tears or meniscus detachment from its insertion follow minor trauma and precipitate severe knee pain in middle-aged and elderly patients. The purpose of this paper is to demonstrate the key points for diagnosis through examination of the clinical features of this tear.


METHODS
Arthroscopic examination of 250 knees with medial meniscus tears (and no ligamentous injuries; over 40 years old) identified 26 knees (26 tears) with a posterior horn tear. Of these 26 tears, 16 were radial, and 10 were detached.


RESULTS
Eighty-five percent of patients could recall discrete events that preceded the pain. They described these events as a click or a feeling of shock. Afterwards, most patients complained of severe pain or giving way. Hydrarthrosis involving more than 5 ml was present in 81%. Most radiographs (92%) appeared nearly normal.


CONCLUSIONS
It is important to note that this type of tear of the posterior horn in the medial meniscus is not rare. Because this area is difficult to visualize arthroscopically, it may be overlooked unless the threshold of suspicion is lowered.
Habata
T
T
Department of Orthopaedic Surgery, Nara Medical University, 840 Shijo, Kashihara, 634-8522 Nara, Japan. habatata@naramed-u.ac.jp
Uematsu
K
K
Hattori
K
K
Takakura
Y
Y
Fujisawa
Y
Y
D000368:Aged; D001182:Arthroscopy; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000175:diagnosis* / Q000601:surgery; D008875:Middle Aged; D000070600:Tibial Meniscus Injuries