The incidence and cross-sectional area of the meniscofemoral ligament

Background: The incidence, morphologic characteristics, and cross-sectional area of meniscofemoral ligaments of the knee are still not clarified. Hypothesis: The incidence of meniscofemoral ligaments is very high, and they contribute significantly to the cross-sectional area of the posterior cruciate ligament complex. Study Design: Descriptive laboratory study. Methods: Clinical study: During arthroscopic anterior cruciate ligament reconstruction, the presence of a meniscofemoral ligament was confirmed in 38 patients (16 men, 22 women; mean age, 23.6 years) by observation and probing. Laboratory study: Posterior cruciate ligaments with the lateral meniscus attached were obtained as specimens from 30 patients (3 men, 27 women; mean age, 71.9 years) during total knee arthroplasty. The posterior cruciate ligament and meniscofemoral ligaments were observed, and the cross-sectional area was measured using an area micrometer. Results: Clinical study: The anterior meniscofemoral ligament was found in 36.8% of patients, the posterior meniscofemoral ligament was found in 71.1 %, and both ligaments were found in 26.7%. The overall incidence of at least 1 meniscofemoral ligament was 84.2%. Laboratory study: The anterior meniscofemoral ligament was present in 5 (16.7%) cases, and the posterior meniscofemoral ligament was present in all cases (100.0%). The cross-sectional area of the posterior cruciate ligament proper was 50.1 +/- 16.9 mm(2), that of the anterior meniscofemoral ligament was 2.3 +/- 1.2 mm(2), and that of the posterior meniscofemoral ligament was 7.5 +/- 2.5 mm(2). The mean ratio of the cross-sectional area of meniscofemoral ligaments to the posterior cruciate ligament proper was 17.2% (4.0%-38.9%). The origin of the posterior meniscofemoral ligament from the posterior horn of the lateral meniscus could be classified into 5 types. Conclusion: The meniscofemoral ligaments contributed significantly to the cross-sectional area of the posterior cruciate ligament complex.