Sciatic nerve block in the popliteal fossa: description of a new medial approach.
OBJECTIVE
Sciatic nerve blocks through lateral approaches in the popliteal fossa have been proposed. We describe a new medial approach to the sciatic nerve at this level.


METHODS
After an anatomical study on six cadavers, we performed sciatic nerve blocks on 20 patients. A 100-mm insulated needle and a nerve stimulator were used; 20 mL of lidocaine 1.5% with epinephrine were injected.


RESULTS
Patients lied in the supine position, the thigh flexed, abducted and rotated externally (30 degrees in all directions). The leg was flexed at 130 degrees . In this position, above the adductor tubercle, a depression known as Jobert's fossa is palpated. Through this groove, a medial approach to the sciatic nerve at the level of the popliteal fossa is possible. The mean distance between the adductor tubercle and the puncture site is 6.18 cm (range 4-8 cm) and the mean distance between the skin and the sciatic nerve is 6.62 cm (range 4-9 cm). Mean time to perform the block was 100 sec (range 55-165 sec). Complete motor blockade was obtained after a mean time of 30 min (range 5-60 min) inside the common peroneal nerve area and 43 min (range 15-75 min) inside the tibial nerve area. Motor block was complete in 17 patients and sensory block in 18 patients. No vessel puncture was observed.


CONCLUSIONS
We describe a new medial approach to the sciatic nerve in the popliteal fossa. More studies will be required to demonstrate the technique is effective and safe.
Departments of Anesthesiology, Université Libre de Bruxelles, C.H.U Saint-Pierre, Brussels, Belgium. eguntz@ulb.ac.be <eguntz@ulb.ac.be>
Emmanuel
E
Guntz
Pierre
P
Herman
Eric
E
Debizet
Damien
D
Delhaye
Very
V
Coulic
Maurice
M
Sosnowski
D000322:Adrenergic Agonists / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D000779:Anesthetics, Local / Q000627:therapeutic use; D002102:Cadaver; D004837:Epinephrine / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000627:therapeutic use; D008297:Male; D008488:Medical Illustration; D008875:Middle Aged; D009407:Nerve Block / Q000295:instrumentation / Q000379:methods*; D011446:Prospective Studies; D012584:Sciatic Nerve / Q000033:anatomy & histology; D012684:Sensory Thresholds; D016683:Supine Position; D013848:Thigh / Q000000981:diagnostic imaging; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods
D000322:Adrenergic Agonists; D000779:Anesthetics, Local; D008012:Lidocaine; D004837:Epinephrine