From: Michael Klevens
Date: Sat 30/11/2002 00:17

Sorry for the cross post, but I wanted to see if there are distinctly differing opinions on the following scenario.

31 y.o. obese female with left posterior knee dislocation, associated open wound in popliteal fossa and probable right knee dislocation which was reduced during patient transfer. Patient has obvious ligamentous laxity in right knee. Other injuries: left humerus fracture, medial orbital wall fracture. Cause of injury: pedestrian vs. car. For this discussion, the patient is stable and mentating well and is tentatively cleared of all other injuries by XR, FAST and CT scan (H/A/P/T). PT/DP and popliteal pulses are 2+ and ABIs are 1.0. Sensation is also intact. The question: Angiography or just monitor pulses and ABIs? There has been the reflex that we should always go to angiography in these cases, but the orthopedic resident on-call said that we could just monitor the pulses and ABIs. We ended up going to angiography. Any comments?

Michael Klevens, MD
Temple University Hospital
Philadelphia

From: Ken Mattox
Date: Sat 30/11/2002 02:06

Yes, I am still of the school that in this case, one should always get an arteriogram. To not get an arteriogram is to gamble with the patient's extremity and possibly with their life. That is not what we are in the business for.

k

From: Sal Sclafani
Date: Sat 30/11/2002 03:18

Questions:

1.will you explore and repair intimal tears?
2. Will you treat intimal tears with antiplatelet therapy
3. will the patient undergo CT scan with contrast for some other reason?
4. Do you have a multi-detector CT (mdct), do you have ready availability of angiography?

If you will explore all minor popliteal injuries, then I would do an arteriogram
If you would treat by anticoagulation or antiplatelet therapy intimal injuries, then I would do an arteriogram
If the patient will undergo Contrast CT for another reason I would look at the popliteal arteries with a CT angiogram if a mdct is available

Otherwise in an asymptomatic patient I would watch

Sal

From: Eric Frykberg
Date: Sat 30/11/2002 03:51

The answer to this question is well documented in at least 6 studies over the past 10 years, showing not a single case of arterial injury requiring surgical intervention in patients with knee dislocation and no hard signs of arterial injury--altho arterial injuries are found in such cases (about 10%), they are ALL asymptomatic nonocclusive injuries which are well known to have a benign natural history as long as hard signs do not develop.

In 264 published cases over the past 10 years of knee dislocation in which the physical findings were correlated with clinical presentation, 77% presented without hard signs--as in the described case, this is how the great majority present--and in that group, not a single case of arterial injury ever requiring surgery was found.

There are 5 hard signs which must be documented, absent pulses just being one, the others being active bleeding, large expanding or pulsatile hematoma, bruit or thrill, and distal ischemia(the 5 P's). Althouhg a total of 23 arterial injuries were found (all cases arteriogrammed for the studies), all were asymptomatic (obviously!) nonocclusive types, and all were followed for periods up to one year without a single published case yet requiring surgery in this settting. Thus, they do not require detection, and the physical exam alone can determine management. As in all other forms of extremity injury, this further confirms the absence of hard signs rules out a surgically significant vascular injury with reliability approaching 100% (i.e. as reliably as any other modality applied to extremity injury evaluation, but far less costly, less invasive, and safer). In 23% of cases, hard signs were present, and in 70% of those cases, a surgically significant vascular injury was present.

Thus in the PRESENCE of hard signs, arteriography is warranted, only to avoid unnecessary vascular exploration in 30% of cases (30% false positive rate, 0% false negative rate of physical exam)--although just going right to the OR in the presence of hard signs could be supported. Although the dogma of past decades of routine arteriography for all cases of knee dislocation was reasonable to err on the side of caution, before any data was developed to test this, there is no data ever yet published to support such an expensive practice--now we know better, and every bit of published data on this subject from every study ever to look at the correlation with phys exam refutes this dogma.

Alas, to let go of such cherished yet unfounded beliefs is like moving a mountain--just look at how long it took DATA to finally override MAST trousers and cyclic hyper-resuscitation, eh Ken? Anyone who continues to support this dogma has a lot of explaining to do in terms of reconciling such an untenable stance with the published evidence. We are now far beyond the ability of anyone to get away with just saying "the heck with the data, this is what I just have to believe...."--that is, assuming evidence (i.e. science) means anything to us. It is now their burden to do more than just rail at how this just cannot be, and develop data to support their stance and refute what now exists. There are some members of this list who are the authors of some of the supporting data below, who may also chime in.

For the refs on this see, for a start:

Applebaum et al, Am J Surg 160:221, 1990
Treiman et al, Am J Surg 1992
Martinez et al, Am Surg Feb 2001
Miranda et al. J Trauma, Feb 2002 (presented AAST 2000)
Dennis et al. J Trauma Dec 1993 (presented EAST 1993)
Frykberg, Surg Clin N Amer Feb 2002
TRAUMA, 5th ed Moore, Feliciano, Mattox (eds), ch. 43 (in press)
Special Problems, in: VASCULAR TRAUMA, 2nd ed, Mattox, Rich (eds), in press.

ERF

From: Michael Klevens
Date: Tue 03/12/2002 03:31

Thank you all for your insightful responses. It seems that my emergency medicine colleagues with one strong and well documented exception favor angiography. Maybe it is just that we don’t have to care for those folks past the course of a half-day and we feel better if we have a definitive study. For those that favor a non-angio route for patients without hard signs, keep educating us in the emergency department! This goes for permissive hypotension, six-hour protocols for certain types of penetrating trauma and other clinical scenarios. By the way, angio on our patient found an intimal flap on the less severely injured knee. The very knee that we weren’t worried about! The more damaged knee had nothing on angio. There was no vascular surgical intervention needed on the flap.

From: Eric Frykberg
Date: Tue 03/12/2002 13:58

Michael

Thanks for the followup--of course, the result should have been no surprise--the angio changed nothing, and the flap that was found did not need treatment ( at least that was recognized!), and therefore did not need to be found. The way to "educate" your colleagues is not for us to sit here and tell them what the literature shows--it is for them to READ and find out for themselves! This will serve their patients best. The data is out there, and is quite clear, and has been there for years.

ERF

From: Sal Sclafani
Date: Tue 03/12/2002 22:54

While there are few reported complications of intimal flaps of the popliteal artery in patients with intimal flaps, has anyone besides myself had such an experience?

Mine was a young polytraumatized patient who developed a heel ulcer after nonoperative treatment (without platelet inhibition) of his popliteal intimal flaps. His popliteal artery intimal injury, forgotten during managment of more complicated injuries, ultimately thrombosed. AFter revascularization his heel healed.

Sal