Risk factors associated with amputation in civilian popliteal artery trauma

Popliteal artery trauma is uncommon but is associated with a high risk of limb loss depending on the scenario involving blunt or penetrating trauma as well as the severity and extent of injury that has occurred. In our setting there is a significant amount of gang and civilian warfare resulting in Vascular Trauma. There were 32 patients over a decade who sustained traumatic injury to the popliteal artery consisting of 30 males (94%) and 2 females with an age range 16-59 years with a mean of 32. There were 20 cases of penetrating trauma (63%) and 12 cases of blunt trauma (37%). Of the penetrating trauma, 18 were due to gunshot wounds (GSWs) (90%) and 2 stabs. The majority (7/12; 58%) of blunt trauma was due to falls, and 42% (5/12) secondary to motor vehicular accidents (MVAs). In terms of extent of injury, 21 of 32 patients (65%) sustained an isolated popliteal artery injury, whilst 6 (19%) had injury to both the popliteal artery and vein and another 5 (16%) had combined popliteal artery, vein and nerve injuries. There were 14 cases with associated orthopaedic injuries: 7 posterior knee dislocations, 1 fracture/dislocation of the knee, 2 femoral fractures, 2 tibial plateau fractures and 2 tibia/fibula fracture. Methods of repair included 14 reversed vein grafts, 16 polytetrafluoroethylene (PTFE) grafts and 2 primary. The overall amputation rate was 28% (9 patients). Of the penetrating trauma patients 25% required amputations composed of 5 GSWs, 33% of the blunt trauma patients required amputations. It was noted that factors associated with (but not statistically significant) poor outcomes included combined artery/vein injury, artery/vein/nerve injury, concomitant fracture/dislocation and delayed transfer to a Vascular Surgery Unit. The type of graft or repair did not affect outcome. The incidence of popliteal artery trauma was calculated at 2.46 per 100,000 population per year.