0:00

What I wanna emphasize about unipennate strains is

0:04

that the injury takes place at the muscle surface.

0:07

And because of that, we will often see considerable amounts

0:11

of fluid at the muscle surface.

0:14

This is particularly an issue in the injuries

0:17

that we frequently see in the calf,

0:20

where there's a potential space between the soleus

0:23

and the gastrocs

0:24

to allow the plantar tendon to pass through.

0:27

So because we have a potential space,

0:30

we may see fluid accumulating in that area.

0:33

And the reason I wanna emphasize this is

0:36

that when you are grading your muscle injuries, I want you

0:40

to just try to ignore the fluid.

0:42

The amount of fluid outside the muscle

0:45

doesn't really affect the grading of the injury.

0:49

It is the degree of anatomical injury of the muscle

0:53

and injury of the tendon.

0:55

So here we have a low grade, uh, pattern,

0:58

and on this image we can see

1:00

that the injury is higher grade.

1:02

This is actually the same patient, more posterior, uh, here.

1:06

And you can see that by the time we come to this region

1:09

that the tendons actually disrupted

1:11

and we have architectural distortion with voids, uh,

1:15

in the tendon, but be cautious

1:17

and try to ignore the amount of fluid.

1:20

This is a case, uh, given to me by a, uh,

1:23

prominent MSK radiologist in uh, England.

1:27

And, uh, he doesn't mind that I tell you

1:29

that it's his own leg

1:31

and he, it sustained an injury playing, uh,

1:34

while he was skiing

1:36

and was able to ski, uh, four days later.

1:38

So again, despite this very, very large amount of fluid

1:42

between the gastroc anemia, so the soleus,

1:44

he clearly has an, a neurotic injury that's distal,

1:48

but be, don't be dissuaded by this much fluid, uh, that can,

1:52

uh, that can resorb.

1:53

And he was able to get back to sport, uh,

1:56

relatively quickly.

1:57

These are very common and you should be aware of these,

2:01

and they happen, uh,

2:03

because the, uh, orientation of the muscle fibers

2:06

of the gastroc anemias and of the sous are not the same.

2:10

And so we tend to get a traction injury in the terminal.

2:13

Gastroc Venus.

2:15

This is a mild one, a more severe and lengthy one.

2:18

And, uh, Brady Wong, uh,

2:20

today showed me a really beautiful new example

2:22

that unfortunately I didn't have time to get, uh,

2:25

into this, uh, particular lecture.

2:26

But, uh, on the ultrasound with the cine, uh,

2:29

you could clearly see the differential movement

2:32

of the ap neurosis of the gastroc anus

2:35

and the soleus reflecting the separation, uh, between those,

2:38

uh, those two structures.

2:41

Now, unlike the unipennate muscles,

2:43

the bi penate muscles have muscle fibers coming at 'em

2:47

from both sides.

2:49

And I think the supraspinatus is a lovely example of that.

2:52

Here we can see the tendon note the more, uh,

2:56

oblique orientation of the tendon

2:59

Vis-a-vis the muscle fibers that's characteristic

3:01

of the supraspinatus.

3:03

And we can see that there is edema, uh,

3:05

on both sides preferentially in the more posterior fibers in

3:09

this, uh, particular example.

3:11

But these, uh, bi penate, uh, tend

3:14

to not have a lot of swelling.

3:15

They're not near the surface.

3:17

They don't tear the superficial vessels.

3:20

And so we don't tend to get a lot of epi mycelial fluid, uh,

3:23

with bi penate, uh, strains.

3:25

I don't see as many, uh, of these

3:28

as I do the uni penate, uh, strains.

3:30

By far. We do see supra spinata strains.

3:33

Often they're related, uh, to weightlifting, uh,

3:37

but they are pretty unusual compared to calf

3:40

and thigh strains, uh,

3:41

where we see the majority of our trauma.

3:44

I.