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[ASSOCIATION OF ANTERIOR CRUCIATE LIGAMENT DEGENERATION WITH MEDIAL MENISCUS TEAR AND INTERCONDYLAR NOTCH IMPINGEMENT].

OBJECTIVE
To explore the association of anterior cruciate ligament (ACL) degeneration with intercondylar notch impingement and the medial meniscus tear in knee osteoarthritis (KOA).


METHODS
Between July 2014 and February 2016, 55 KOA patients (55 knees) with ACL degeneration (degeneration group) and 55 KOA patients (55 knees) without ACL degeneration (control group) were included in the study. No significant difference was found in gender, age, body mass index, and side between 2 groups (P>0.05). The notch width index was measured on preoperative MRI to evaluate whether the intercondylar notch was narrow. The location of the medial and lateral meniscus tear and osteophyte of the ACL tibial insertion were observed under arthroscopy, and the incidences of the meniscus tear and osteophyte were calculated.


RESULTS
There was no significant difference in anterior horn and body tear of the medial meniscus and in anterior horn, body, posterior horn, and root tear of the lateral meniscus (P>0.05). Significant difference was found in the posterior horn and root tear of the medial meniscus, osteophyte of the ACL tibial insertion, narrow intercondylar notch, and the notch width index between 2 groups (P<0.05). The incidence of root tear of the medial meniscus was 53.8% (7/13) in 13 knees with osteophyte of the ACL tibial insertion and was 16.5% (16/97) in 97 knees without osteophyte, showing significant difference (χ2=9.671, P=0.002).


CONCLUSIONS
There is a strong association of ACL degeneration with posterior horn and root tear of the medial meniscus and intercondylar notch impingement in KOA. And the high incidence of root tear of the medial meniscus in knee is correlated with osteophyte of the ACL tibial insertion.