- Arterial Trauma
- Compartment Syndrome
- Knee Dislocation
- Popliteal Artery
- Reperfusion Injury
- note that the worst error to make is to underestimate the need to promptly treat these injuries;
- there are anecdotal reports of patients who ended up with AKA (from vascular injury) who were reported to have diminished but "dopplerable pulses;"
- ref: What Is the Frequency of Vascular Injury After Knee Dislocation?
- Vascular and Nerve Injury After Knee Dislocation: A Systematic Review
- What Is the Frequency of Vascular Injury After Knee Dislocation?
- compartment syndrome:
- compartment syndrome is a frequent complication of knee dislocation, attributable to vascular injury and resultant ischemia;
- four compartment fasciotomy is indicated in these situations;
- Diagnosis of Vascular Injury:
- pulse deficit is seen in up to 84% of limbs, whereas indications of ischemia are present in only 60%;
- however, distal pulses do not rule out arterial injury;
- Measurement of the ankle-brachial index (ABI)
- The value of the ankle-brachial index for diagnosing arterial injury after knee dislocation: A prospective study.
- indications for arteriogram are unclear, since cases w/ clinical evidence of vascular injury should procede immediately to the OR (where
an intraoperative arteriogram can be obtained);
- in most cases, popliteal artery injury is at the level of the knee joint, and an arteriogram in the face of obvious injury is not required and
causes unnecessary delay for arterial reconstruction;
- w/ intimal flap tears with normal pulses, is observation for 48 to 72 hours;
- incidence of vascular injuries is more common w/ posterior than anterior dislocations because of higher force needed to produce this injury;
- posterior dislocations:
- more likely to result in direct injury & even rupture of popliteal artery (isolated transection);
- anterior dislocations:
- stretching of popliteal artery may lead to intimal disruption & thrombosis (damage is over a longer segment of the artery)
- frxs of distal femur or tibial plateau may also cause contusion of popliteal artery with intimal disruption and thrombosis;
- The role of arteriography in assessing vascular injuries associated with dislocations of the knee.
- Examination of the patient with a knee dislocation. The case for selective arteriography.
- Vascular Injuries in Knee Dislocations: the Role of Physical Examination in Determining the Need for Arteriography.
- Non Operative Treatment:
- in some cases, reduced knee dislocation will demonstrate stable pulse and no injury on arterogram;
- it is controversial whether these patients will require anticoagulation;
- see pharmocologic agents used in vascular surgery
- Pre Op Planning:
- both before and after surgery consider whether reperfusion injury and/or compartment syndrome is possible;
- if limb ischemia > 6 hrs perform fasciotomy because reperfusion injury may lead to compartment syndrome;
- anticipate that popliteal vein may also be injured and anticipate need for repair;
- w/ popliteal arterial injury use of contralateral saphenous vein graft, since an ipsilateral popliteal vein injury is common;
- injuries to popliteal veins should be repaired because there is a high incidence of edema and potential compartment syndrome.
- pharmocologic agents used in vascular surgery
- Arterial Reconstruction:
- surgical approach is through a postero-medial incision, which begins at the adductor tubercle and ends distally 10 cm below the joint line;
- the saphenous vein and nerve are protected;
- deep exposure:
- transect the pes anserinus tendons and the semimembranosus tendons, 2 cm above their insertions;
- these can be tagged for lateral closure;
- transect the gastroc at its tendinous origin;
- it is necessary to have exposure of the popliteal artery from the adductor hiatus to the trifurcation;
- direct exposure of the artery may be difficult due to associated frx, and hematoma;
- in this case, first expose uninvolved areas of the arterial system;
- proximal and distal control of popliteal artery are obtained.
- vessel is debrided;
- choice of graft:
- interposition grafting w/ contra-lateral saphenous vein is procedure of choice except in select cases in which an end-to-end anastomosis
can be accomplished without undue tension;
- prosthetic grafts should be reserved for use in those pts in whom saphenous vein grafting is not possible.
- note that in general prosthetic grafts have a poor tract record when used below the knee;
- completion arteriography outlines any technical defects.
- technique of repair:
- End to Side
- End to End
- Pharmocologic Agents Used in Vascular Surgery
- fasciotomy may be performed at this point if needed;
- ligament reconstruction:
- the posteromedial exposure allows assesment of the MCL and PCL, and each of these should be repaired if possible;
- knee stabilization:
- knee can be stabilized in extension with a Steinman pin
Vascular injuries associated with dislocation of the knee.
Arterial injury complicating knee disruption. Third place winner: Conrad Jobst award.
Arterial injuries associated with complete dislocation of the knee.
Civilian popliteal artery trauma: an eleven year experience with 83 injuries.
Complete dislocation of the knee with popliteal vascular injury.
The value of the ankle-brachial index for diagnosing arterial injury after knee dislocation: a prospective study.
Multiligamentous Injuries of the Knee and Associated Vascular Injuries