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Is intra-articular pathology associated with MCL edema on MR imaging of the non-traumatic knee?
Donna G Blankenbaker1, Arthur A De Smet, Jason P Fine
1Division of Musculoskeletal Imaging, Department of Radiology, University of Wisconsin Medical School, Clinical Science Center-E3/311, 600 Highland Avenue, Madison, WI 53792-3252, USA. dg.blankenbaker@hosp.wisc.edu
Objective:
Edema surrounding the medial collateral ligament (MCL) is seen on MR imaging in patients with MCL injuries and in patients with radiographic osteoarthritis in the non-traumatic knee. Because we noted MCL edema in patients without prior trauma or osteoarthritis, we studied the association between intra-articular pathology and MCL edema in patients without knee trauma.
Design And Patients:
We evaluated the MR examinations of 247 consecutive patients (121 male, 126 female with a mean age of 44 years) without recent trauma for the presence of edema surrounding the MCL, meniscal and ACL tears, medial meniscal extrusion, medial compartment chondromalacia, and osteoarthritis. The percentages of patients illustrating MCL edema with and without each type of pathology were compared using Fisher's exact test to determine if there was a statistically significant association.
Results:
We found MCL edema in 60% of 247 patients. MCL edema was present in 67% of patients with medial meniscal tears, 35% with lateral meniscal tears, 100% with meniscal extrusion of 3 mm or more, 78% with femoral chondromalacia, 82% with tibial chondromalacia, and 50% with osteoarthritis. The percentage of patients with edema increased with the severity of the chondromalacia. These associations were all statistically significant (p <0.02). The mean age of those with MCL edema was 49.7 years compared with 34.9 years without MCL edema ( p <0.001). Patient gender and ACL tear did not correlate with MCL edema. Nine (4%) of the 247 patients had MCL edema without intra-articular pathology. None of these 9 patients had MCL tenderness or joint laxity on physical examination.
Conclusions:
We confirmed that MCL edema is associated with osteoarthritis, but is also associated with meniscal tears, meniscal extrusion, and chondromalacia. In addition, MCL edema can be seen in patients without intra-articular pathology, recent trauma or MCL abnormality on physical examination.
Insights
Medial collateral ligament (MCL) edema on MRI is linked to various knee pathologies, including meniscal tears and chondromalacia. This edema can also occur without intra-articular issues in non-traumatic knees.
Area of Science:
- Orthopedic Imaging
- Knee MRI Analysis
- Ligament Pathology
Background:
- Medial collateral ligament (MCL) edema on MRI is often associated with MCL injuries or osteoarthritis.
- However, MCL edema is also observed in patients without apparent trauma or osteoarthritis.
- This suggests potential links between MCL edema and other intra-articular pathologies.
Purpose of the Study:
- To investigate the association between intra-articular pathologies and MCL edema in patients presenting without knee trauma.
- To determine if conditions like meniscal tears, chondromalacia, or extrusion correlate with MCL edema.
Main Methods:
- Retrospective analysis of 247 non-traumatic knee MRIs.
- Evaluated for MCL edema, meniscal tears, ACL tears, meniscal extrusion, chondromalacia, and osteoarthritis.
- Used Fisher's exact test to assess statistical significance of associations.
Main Results:
- MCL edema was present in 60% of patients.
- Significant associations found between MCL edema and medial meniscal tears (67%), meniscal extrusion (100% for >=3mm), femoral chondromalacia (78%), tibial chondromalacia (82%), and osteoarthritis (50%).
- Edema severity correlated with chondromalacia severity; MCL edema occurred in 4% without intra-articular pathology.
Conclusions:
- MCL edema is associated with osteoarthritis, meniscal tears, meniscal extrusion, and chondromalacia.
- MCL edema can be present in individuals without intra-articular pathology, trauma, or physical examination abnormalities.
- MRI findings of MCL edema warrant consideration of underlying intra-articular knee conditions.
