Prevalence of Meniscal Extrusion and associated Knee Findings Detected by MRI in Patients with a History of Knee Trauma

Author(s):

Media S Ibrahim and Sameeah A Rashid

Background and objectives: Meniscal extrusion is defined as the condition in which the meniscus is located outside the margin of the knee joint. This condition can lead to knee osteoarthritis, meniscal degeneration, and meniscal tears. Meniscal extrusion is broadly diagnosed through magnetic resonance imaging. The present study aimed to examine the prevalence of meniscal extrusion and the associated knee joint abnormalities in cases of trauma. Methods: The present cross-sectional study consisted of 122 cases (62 cases with knee injuries caused by falling on ground and 60 as a result of football playing) whom been referred to MR unit to undergo knee exam referred in the period from January to July 2019. A search for meniscus extrusion was performed, and once identified then checking for associated findings was performed. Results: The study group mean age was 31.77 years. Most of the cases (77%) were males. About one third of the cases (30.3) had meniscal extrusion, and almost half of them (48.4%) had meniscal tear. Meniscal root tear and complex tear of posterior horn of medial meniscus was the most frequent meniscal tear. About half of the cases (49.2%) had joint effusion. In both study subgroup, meniscal extrusion was significantly found in the medial meniscus, and it was significantly associated with medial meniscus tear, types of meniscal tear, and joint effusion (p<0.05). Age had a significant association with meniscal extrusion in the subgroup of trauma caused by falling on ground (p<0.05), the two groups were significantly different in terms of the meniscal extrusion distance (p<0.05). Conclusion: Medial meniscus and medial meniscus tear are the most significant risk factors for meniscal extrusion. Meniscal extrusion distance was shorter in individuals with knee trauma caused by football playing compared to those with knee injuries resulted from falling on ground.