Welcome to the emDOCs.net podcast with Brit Long, MD (@long_brit) and Manpreet Singh, MD (@MprizzleER)! Join us as we review our high-yield posts from our website emDOCs.net.
Today on the emDocs cast with Brit Long, MD (@long_brit), Manpreet Singh, MD (@MprizzleER), and Rachel Bridwell, MD (@rebridwell) we cover two posts: tibial plateau fracture and knee dislocation.
To continue to make this a worthwhile podcast for you to listen to, we appreciate any feedback and comments you may have for us. Please let us know!
Subscribe to the podcast on one of the many platforms below:
Welcome to the emDOCs.net podcast with Brit Long, MD (@long_brit) and Manpreet Singh, MD (@MprizzleER)! Join us as we review our high-yield posts from our website emDOCs.net.
Today on the emDocs cast with Brit Long, MD (@long_brit), Manpreet Singh, MD (@MprizzleER), and Rachel Bridwell, MD (@rebridwell) we cover two posts: tibial plateau fracture and knee dislocation.
To continue to make this a worthwhile podcast for you to listen to, we appreciate any feedback and comments you may have for us. Please let us know!
Subscribe to the podcast on one of the many platforms below:
emDocs Podcast Script:
Brit: Today on the emDocs podcast we have something a little different. We’re going to cover a couple of EM@3AM posts, and to help us, we have the rock star Rachel Bridwell, who’s a current chief resident in San Antonio, TX. Rachel’s posts cover a very similar patient, a younger male with severe blunt lower extremity trauma.
Let’s start with tibial plateau fracture. Rachel, how common are these, and who should we consider the diagnosis in?
Rachel: First on epidemiology and patient scenarios….People with knee owies. Young guys with high energy mechanisms under 50 and older women over 70 with low E mechanisms
Brit: These patients typically present in discomfort, refusing to bear weight on the affected extremity, and they may have effusion, open soft tissue injury, ligament injury, and neurovascular deficits present. The post covers a classification system, which we won’t go into detail because you won’t remember. Just remember that the more severe injury or the more bone and articular surface involved, the more intervention needed. Please go to the post for more on this classification.
What about diagnostic imaging. Can we just rely on Xray, or do we need something more?
Rachel: Rachel on XR and CT
XR is a good place to start, but SN for fx is only 85% even with 4V. CT is much better, with SN and SP of 93-98% and SP of up to 98.5%. It can not only show site, displacement, and bony fragments, but lipohemarthrosis
Brit: What are some complications that can occur? Everyone remembers the risk of compartment syndrome, but how common is this, and there have to be others...
Rachel: Rachel on mainly compartment syndrome, just list the others. Compartment syndrome--11% especially with fibular fractures, longer fx, combined plateau-shaft fx, 30% fibular head fx
Brit: We’ve covered presentation, diagnosis, and complications, but what about management. This is always a tough question in orthopedic complaints, or who needs to OR, and who just needs a splint?
Rachel:
L&U vs knee immobilizer
Immediate surgical management: severely depressed fractures, Compartment syndrome, neurovascular compromise, and open fractures.
Brit: All right, let’s move to the next injury, knee dislocation. I’ve found these to be either subtle or grossly apparent in patients with significant trauma. What are the types of knee dislocations, and who’s at risk?
Rachel on Epidemiology, high energy, obesity.
High E-- dashboard in MVC
Low E-- obese individual stepping off curb
Obesity is an independent risk factor, nearly 50% of knee dislocations occurring in people with BMI> 40
Brit: This is a big point; many knee dislocations spontaneously reduce prior to patient presentation to the ED, making this even more difficult. Before we get ahead of ourselves, what are concerned with when it comes to knee dislocations?
Rachel briefly on anatomy: ligaments, nerve/vascular injury
In order to dislocation your knee, it requires a full disruption of your ACL, PCL, MCL, LCL
Popiteal artery, tethered back in the fossa, has a high risk of injury in around 40% of patients
Running around the fibular neck, the peroneal nerve has a high risk of damage as well.
Brit: That’s right, we’re looking for nerve and vascular injuries in these patients. If we have a patient with suspected knee dislocation, like we talked about, many will have a spontaneously reduced knee. What should we look for on exam?
Rachel: Physical exam, ABCDE-- big energy- do what we do best
Put knee in 20 degrees of flexion
Check for multidirectional instability
If the contralateral side is uninjured, check it against that side
Obese and low E-- lift by heel and look for hyperextension as 50% of patients will spontaneously reduce PTA
Check for hard findings-- pulse deficit, distal ischemia, rapidly expanding hematoma
Neuro-- L4-S1-- peroneal foot drop
Brit: When it comes to the vascular exam, what are your thoughts on the ABI?
Rachel: ABI lolz
Brit: I’ll be honest, I’m probably going to go straight for a CT with contrast if I think a knee dislocation is present, and this is going to depend on your institution and orthopedic or vascular surgeon preference. And I guess that brings us to imaging… What roles do Xray and CT play?
Rachel: XR can show dislocation and secondary osteochondral defects, since 53% of fx have concomitant dislocations
CT: Popliteal injury can present similar to compartment syndrome, though does not improve with fasciotomy 10 Intimal tears common but not all of them will require operative repair, just require anticoagulation
Brit: Let’s say we have a knee dislocation on exam, maybe with 3 ligaments ruptured in a spontaneously reduced knee, or even worse, the knee is still dislocation. What’s our management?
Rachel: Reduction: immediate as >8 hours has been associated with increased rates of amputation12
Longitudinal traction to tibia13
Grab coags too as these patients often end up on AC
Brit: Rachel, thanks for doing what you do, and I know you’re busy, so I won’t take up any more of your time. Thanks for speaking with me today, and I’m sure we’ll have you back for more.
Thanks for joining us on the podcast, and stay tuned for our next episode. Feel free to comment on our site and let us know if you have any feedback. Stay safe and healthy everyone!