High rate of popliteal artery injuries and limb loss in 96 knee dislocations

Abstract

Background: Knee dislocations are reported to have an incidence of popliteal artery injuries between 7% and 64%. The purpose of this study was to determine the incidence of injuries to the popliteal artery as well as early limb loss in knee dislocations at a level-1 trauma hospital in South Africa. Methods:Twenty-eight patients with popliteal artery injuries were selected from a prospectively collected database of 96 patients with acute knee dislocations. The incidence of vascular injuries, compartment syndromes and limb loss was determined retrospectively. Results:Of 96 knee dislocations 28 had a popliteal artery injury (29.1%). Seven of 28 patients with popliteal artery injuries needed an amputation. Of the 28 patients, ten were documented as a threatened limb. Five of these ten patients (50%) needed an amputation. The documented median delay to revascularisation of patients who presented with threatened limbs was 10 hours. Conclusion:Overall, one-third of knee dislocations presented with a vascular injury. The prevalence of amputations in knee dislocations with associated popliteal artery injuries was 25% and increased to more than 50% in patients who presented with a threatened limb. A recent study has described popliteal artery injury rates as low as 1.6% with only 0.1% of patients needing an amputation.9 Indisputably, each multidirectional knee injury with an adequate history of trauma and presentation should be regarded as a knee dislocation until proven otherwise. 1The mechanism of injury in knee dislocations can range from high energy injuries due to road accidents and falls from a height to low energy injuries such as sports injuries and even ultra-low-velocity injuries such as simple falls, especially in obese patients. [10][11][12][13] The energy level of the injury can affect the injury pattern itself, which varies from ligamentous disruption only, to knee dislocations with severe soft tissue damage, compartment syndrome, open wounds and fractures, all of which are risk factors for adverse limb outcomes. 14,15 In its most severe presentation a knee dislocation can be associated with popliteal artery injuries resulting in a threatened limb and subsequent limb loss if not treated urgently. The specific anatomy of the popliteal artery makes it susceptible to damage during trauma. It is fixed to the distal femur in the adductor canal, and is tethered distally under the soleus muscle and inbetween the two heads of the gastrocnemius muscles. With its tenuous collateral supply, the arterial flow is very rarely sufficient to guarantee adequate distal perfusion to the limb during a complete disruption of the popliteal artery. The purpose of this study was to determine the frequency of popliteal artery injuries in knee dislocations and evaluate the incidence of early limb loss. MethodsTwenty-eight of 96 consecutive knee dislocations admitted to the trauma unit of a tertiary care hospital in South Africa over a period of 12 years (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)...

Vascular Injury After Knee Dislocation: A Meta-Analysis Update

“…The amputation frequency was 2.2% in this study. Studies by Held et al 36 and Plancher and Siliski 37 found higher amputation rates between 10% and 25% in patients with PA injury from KD. Hundersmarck et al 38 showed positive long-term outcomes of (1) early revascularization and (2) bone stabilization before vascular repair if ischemia duration allows.…”

Prioritised challenges in the management of acute knee dislocations are stiffness, obesity, treatment delays and associated limb-threatening injuries: a global consensus study

“…24 25 34 35 Selective angiography triggered by an abnormal ankle-brachial index is often promoted to exclude vascular injuries, 35 but a limited number of healthcare workers or inadequate training of ward staff can make serial neurovascular checks an unsafe strategy. 36 CT angiography, although highly sensitive and specific, might not always be available. Furthermore, in case of arterial damage, vascular surgery and immobilisation via an external fixation device add to morbidity of patients especially due to stiffness and pin site complications.…”

Advances and trends in multiligament injuries of the knee relevant to low-resource settings

“…A single-shot arterial, on-table angiogram before surgical exploration, is a low-cost alternative to evaluate limbs with an absent pulse, active bleeding, expanding hematoma, a popliteal bruit, or distal ischemia. [13] Nerve injury is frequently associated with vascular injury and should be seen as a red flag for vascular injury, even with normal ankle-brachial index. [5] Similar to the vessels, the peroneal nerve is also tethered proximally and distal to the knee and is therefore commonly injured with an incidence of 25-35%.…”