Fig. 4
From: Sports-related lower limb muscle injuries: pattern recognition approach and MRI review
MRI findings and patterns in acute muscle injuries of the lower limb. Tendon injuries showing elongation without a measurable tear (a1), longitudinal tear (a2), and total transverse tear with marked tendon retraction (a3). Peripheral myoaponeurotic/myofascial/myotendinous injuries showing intact aponeurosis (b1), fascial tear (b2), and tendinous complete section with hematoma and retraction (b3). Central myotendinous (septal) injuries showing intact septum (c1), fiber gap of the septum (c2), and total septal tear with loss of tension (c3). Injuries of isolated muscle fibers without disruption (d1) with architectural distortion or blurring (d2), or with measurable tear (d3)