Study of Imaging Pattern in Bone Marrow Oedema in MRI in Recent Knee Injuries and its Correlation with Type of Knee Injury

Abstract

Introduction: The knee is a major weight bearing joint that provides mobility and stability during physical activity as well as balance while standing. If the knee is exposed to forces beyond its physiologic range, risk of injury to bone or soft tissue structures increases. A thorough understanding of knee injury patterns and their mechanisms may help in achieving more accurate assessment of injuries.

Aim: To identify imaging pattern in bone marrow oedema and to correlate the pattern of bone marrow oedema retrospectively with type of knee injury from clinical history.

Materials and methods: A cross-sectional study was done on all patients referred to Krishna Hospital, Karad for MRI knee with history of recent (< 6 weeks) knee injury. Study was conducted between May 2014 to September 2015 with a sample size of 200 patients. Plain radiograph of knee was done in all patients and they were scanned using 1.5 Tesla Seimens Avanto (Tim + Dot) with Tx/Rx 15 channel knee coil # Tim.

Results: Among the 200 cases, bone marrow contusion was noted in 138 cases (69%) and absent contusion in 62 cases (31%). Bone marrow contusion showed five patterns (according to Sanders classification) i.e., Clip injury in 39 cases (28.3%), Pivot shift injury in 78 cases (56.5%), Dashboard injury in eight cases (5.8%), Hyperextension injury in four cases (2.9%), Lateral patellar dislocation in three cases (2.2%). In six cases (4.3%) no pattern of bone marrow contusion could be explained and was categorized as unclassified pattern.

Conclusion: Pivot shift pattern is most common contusion pattern and the most common type/mode of sports related injury. By analysing bone marrow contusion pattern, type/mode can be determined in most of the cases. By applying a biomechanical approach in MR interpretation, it is possible to detect lesions like ligament rupture and osseous contusion, to predict subtle but it might overlook important abnormalities.

Keywords: Bone bruise; Compressisve force; Early degeneration; Microfracture; Torsional force.

[Table/Fig-1a]:

PDFS Saggital: Bone marrow oedema at Lateral femoral condyle in Clip injury pattern.

[Table/Fig-1b]:

T1W Saggital: Bone marrow oedema at Lateral femoral condyle in Clip injury pattern.

[Table/Fig-2a]:

PDFS Saggital: Bone marrow oedema at Lateral femoral and posterolateral tibial plateau in Pivot shift injury.

[Table/Fig-2b]:

PDFS Coronal: Bone marrow contusion at lateral femoral condyle and lateral tibial plateau in Pivot shift injury pattern.

[Table/Fig-3]:

PDFS Saggital: Bone marrow oedema at proximal tibia in Dashboard injury.

[Table/Fig-4]:

PDFS Saggital: Bone marrow oedema at Medial femoral and Medial tibial condyle in Hyperextension injury.

[Table/Fig-5]:

T2 Axial: Bone marrow oedema in Inferiomedial aspect of patella and lateral femoral condyle in lateral patellar dislocation.

[Table/Fig-6]:

Pattern of marrow oedema as per classification. *no pattern of bone marrow contusion could be explained as per the classification.

[Table/Fig-14]:

PDFS Coronal: Bone marrow oedema at Medial femoral condyle and Metadiaphysis.

[Table/Fig-15]:

PDFS Saggital: Bone marrow oedema in Intercondylar region tibia with subchondral cysts.

[Table/Fig-16]:

PDFS Coronal: Bone marrow oedema at Medial femoral condyle and proximal tibia.