[Loco-regional anaesthesia of the lower limbs]

Lumbar plexus and sacral plexus are responsible for sensory and motor innervation of the whole inferior limb and their blockade can be used as a single technique or integrated with general anaesthesia for hip-, femur-, knee-, lower leg-, ankle- and foot surgery. For the performance of the blocks, knowledge of peripheral and central percourse of the nerves and their anatomical relationships to bone-, muscle-, vessel and skin structures is important. In case of the sciatic nerve, a cutaneous projection of the percourse of the nerve is possible (the so-called sciatic line) formed by a virtual line from the midpoint of the line between great trochanter and ischial tuberosity to the apex of the popliteal fossa. Peripheral blocks used for the above mentioned types of surgery are: lumbar plexus block, sacral plexus block, femoral nerve block, obturator nerve block, lateral cutaneous femoral nerve block and sciatic nerve block. Regarding the last one, the following approaches are possible, depending on the anatomical site of performance: classic proximal posterior block, parasacral proximal block, lithotomic posterior proximal block, subgluteal posterior proximal block, anterior proximal block, lateral medio femoral popliteal proximal block, block distal from the poplitea, subcalcaneal block. The terms distal and proximal are in relation to the small trochanter. All blocks have to be performed using a nerve stimulator, teflon insulated needles of various measures depending on the kind of block, variable stimulation from 1,5 mA (when evoking muscle contraction) to 0,5-0,3 mA (injection of local anaesthetic) with frequencies of 2 Hz/0,1 ms.