about ultrasound and mri findings of vastus lateralis injury
This is the case of a young rugby player presenting an high degree strain of the vastus lateralis muscle at its proximal insertion, togheter with an aponeurotic fascial injury on the subcutaneous lateral side.
I always suggest to perform both the Mri and ultrasound investigations; with the Mri exam it is evident the bone marrow edema, due to the avulsion injury at the intertrochanteric line, suspected during the clinical evaluation but impossible to see on ultrasound exam.
Coronal (left) and Sagittal (right) PD-Fs Mri scans (1.5 Tesla).
Axial PD-Fs Mri scan (1.5 Tesla). The bone marrow edema and the avulsion injury are evident.
about ultrasound monitoring of muscle injury remodelling phase
In my recent post Ultrasound Muscle Injuries Monitoring I showed the importance of the dynamic ultrasound and elastosonography exam in the study of the granulation tissue at the site of injury during the rehabilitation program.
Today I want to remind you to take care about muscle also after the final phases of remodeling (3–6 months after trauma), in which maturation of the regenerating fibers into a functional contractile unit takes place.
Axial (left) and Coronal (right) Mri scans of a late left biceps femoris injury evaluation (1.5 Tesla).
In these cases the Mri exam is less sensistive than ultrasound imaging; don’t forget to always perform both imaging modalities.
The patient suspected a reinjury in the same site of a previous trauma; first evaluation was made with an ultraportable device.
The power-doppler exam togheter with the elastosonography evaluation, show an incomplete scar maturation.
About using Ultrasound and Elastosonography imaging in the muscle injuries monitoring.
Deciding when the injured muscle can be remobilized is probably the most crucial decision in the recovery period after a trauma. The process of scar formation begins almost immediately following injury; immature scar tissue is susceptible to reinjury and the formation of granulation tissue at the site of injury needs to be monitored during the rehabilitation program.
2nd degree strain of biceps femoris: ultrasound monitoring in a professional athlete; the two images appear quite similar.
The rehabilitation program is usually regulated with reduced activity until the scar reaches sufficient strength to bear the muscle contraction.
How to differentiate the tissue structural changes in the site of injury?
In my daily practice the elastosonography examination allows to distinguish normal from inadequate healing, working as a “contrast agent” in the site of scar formation.
Looking at the referral colour scale I remind you that red colour means softness and blue colour means hardness.
Same patient studied with elastosonography examination.
15 days after the injury an immature granulation tissue is present (red color in the site of injury), while after 1 month the scar seems to be progressing favorably (blue color is dominant).
In this case the difference between scar tissues elements is more evident with elastosonography than with standard B-mode ultrasound examination. Power-doppler exam demonstrates the revascularization by ingrowing capillaries in the site of injury.
As I showed in my previous post “Are Muscle Strains Hot?” a difference of temperature occurs between the site of injury and the peripheral tissues.
Also in this patient the thermographic evaluation shows an altered temperature diffusion in the left injured tigh; this is another useful information about the progression of the injurious event.
High risk of underestimating the real extent of an high degree muscle strain when using only ultrasound imaging, especially in acute phase; always use power-doppler integration to evaluate the intramuscular and perifascial edema. It’s often frequent to find also a subcutaneous fat pad inflamatory reaction adjacent to the site of injury. Never forget that the more muscle edema is present, the higher echogenicity you’ll find.
High degree strain injury of the adductor longus muscle: dynamic ultrasound examination.
Coronal (left) and Sagittal PdwSpair Mri scans (1.5 Tesla) of the same patient.