My disclosures are in your handouts. It's important to recognize that these are limb-threatening injuries. Up to 50% of knee dislocations will have an arterial lesion. People always ask me, can you rely on physical exam alone? Do you need angiograms on everybody? What about ankle brachial indices? Mills has shown that if the ABI is greater or equal to 0.9, the odds of having a major arterial lesion are zero, 100% negative predictive value. CT angiogram is fast. It's less invasive than conventional angiography because it goes through the antecubital fossa instead of the groin. It's one-fourth the radiation exposure and has outstanding sensitivity. So our current algorithm at the Mayo Clinic for all suspected high-energy knee trauma, tibial plateau, distal femur, floating knees, knee dislocations, is to get ABIs. If they're greater or equal to 0.9, we do serial examination and if they're less, we proceed with CT angiogram. Does vascular injury affect outcomes? You bet it does. This is a two-to-one match cohort of our patients, two to 18-year follow-up. We compared patients with and without vascular injury that required a popliteal artery bypass graft and we found significantly lower functional outcomes. In fact, if you look carefully at the data, the IKDCs in the vascular group, in the 50s, compared to almost 85 in the non-vasculars, similar finding for lysome scores. This is the most important slide of the talk. This is a patient, 16 years old, with a complete popliteal artery occlusion. Collateral flow, very prevalent in these young patients and this patient had a palpable pulse. So you can have a complete arterial occlusion and still have a palpable pulse. Nerve injury occurs in about 10 to 40% of patients. We did a cohort study looking at patients with and without perineal nerve injury and surprisingly, we found no difference in final functional outcomes at final follow-up. Looking carefully at these 27 patients, the ability to restore normal anti-gravity dorsiflexion if they had a partial nerve palsy was about 83%. Compared to 38%, no matter what we did to that nerve, only 38% regained anti-gravity dorsiflexion if they had a complete perineal nerve palsy. Our peripheral nerve surgeons perform direct motor nerve transfers where they basically take a motor branch from the tibial nerve, they ignore the whole perineal nerve and then they find a motor branch that's innervating the tibialis anterior and they hook the two together. And what they found is if they get to this within three months of the injury, before the muscle is denervated, 80% of the patients regain anti-gravity dorsiflexion. So our current approach at the Mayo Clinic is if they're partial palsies, we observe as most of them recover. If they're complete and we can document transection either by ultrasound or MRI, we proceed with direct motor transfer. If they're intact, we watch and repeat the EMGs. And the chronic ones, we proceed with tib tendon transfers. What about external fixation? The current indications for external spanny fixation is to protect a vascular repair, open knee dislocation, and the grossly unstable knee that you just cannot maintain reduction in a brace. Surgical timing, several systematic reviews, Mark Miller's, ours, and others, have all shown that early surgery improves patient outcomes but at a cost of increased risk of arthrofibrosis. These systematic reviews also demonstrate that staging provides good outcomes. This is a new multicenter randomized clinical trial, the first of its kind, the STAR trial. It's funded by the Department of Defense, Jim Ergank from the University of Pittsburgh's, the PI, and there's 18 sites, civilian and military. Two arms of the trial, patients are randomized to acute versus delayed surgery and early versus delayed rehab. So hopefully this trial will shed some light on optimal patient outcomes. I'm gonna show you two quick cases. This is a nerve injury patient. 18-year-old male fell off a roof. Complete knee dislocation, perineal nerve palsy, transected perineal nerve on MRI and ultrasound, transected. Here you can see his MRI where he has ACL, PCL, and a very extensive post-lateral corner FCL disruption. We do his ACL and PCL grafts. Lateral side, we did a repair and augmented with a graft, as I've shown in Jim's standard, unacceptably high failure rates with repair alone. So then the peripheral nerve team came in, did the motor transfer, and here's his ACL, PCL lateral side with repair and augmentation, and here's his motion at nine months follow-up, and this is what's amazing. Look at this, completely transected nerve, nerve transfer, dorsiflexion restored. This next case, the last case, a vascular injury, 17-year-old male, he's in a water slide. You know those big tubes that you go down at like 50 miles an hour and you tuck yourself? Well, this kid, he didn't have enough speed. He's wearing those little sticky water shoes, and he decides to lean back in the tube to get a little bit more speed. His foot comes up, sticks on the tube, and dislocates his knee. So this is how he comes out of the tube. Took out his palpiteal artery. So in St. Louis, they did saphenous vein bypass grafting, four compartment fasciotomies, and put him in a spanning fixator, and then they transferred him to Mayo a few weeks later. Here's his ACL and PCL disruption. Here's his lateral side, so ACL, PCL, lateral side. And this is the tricky part of this case. That bypass graft, which is now a vein, not an artery, is right where I gotta make a 12-millimeter socket. So I get all the way down the PCL facet by establishing a post-mutal portal. I'm off the champagne drop-off. I get my guide in place, drill, ream, clear out the bone. Heart rate's pumping at 220. And I'm looking at 9-0 proline suture. How I didn't hit it, I don't know, but somebody was with us praying. So here's his ACL, PCL. We used a technique, the Mayo HSS technique that Bob Marks and I have written up several times with comparable outcomes to LeProd's. And here's his ACL, PCL, lateral side. And here he is at 11 months post-op. And it's kids like this that keep us coming back for more. Thank you very much. Thank you.

limb-threatening injuries

knee dislocations

arterial lesions

vascular injuries

nerve injuries