Official reprint from UpToDate®
www.uptodate.com ©2017 UpToDate, Inc. and/or its affiliates. All Rights Reserved.

Lower extremity nerve blocks: Techniques

Christina L Jeng, MD
Meg A Rosenblatt, MD
Section Editor
Lisa Warren, MD
Deputy Editor
Marianna Crowley, MD


Peripheral nerve blocks of the lower extremity are used for operative anesthesia and/or postoperative analgesia for a variety of lower extremity surgeries.

This topic will discuss the innervation of the lower extremity, techniques and drugs used for lower extremity nerve blocks, and complications specific to these blocks. Where appropriate, the use of perineural catheters for continuous nerve block will be discussed. Indications, contraindications, comparison of techniques relevant to all peripheral nerve blocks, equipment, and complications common to all nerve blocks are discussed separately. (See "Overview of peripheral nerve blocks".)


The lumbar plexus is formed by the anterior divisions of the first three lumbar nerves (L1, L2, L3) and part of the fourth lumbar nerve (L4). A branch from the 12th thoracic spinal nerve (T12) often joins the L1 nerve root (figure 1).

The lumbar plexus is located in the posterior third of the psoas muscle, anterior to the lumbar transverse processes. It gives rise to nerves that supply the muscular and cutaneous innervation to the lower extremity, including the iliohypogastric nerve, ilioinguinal nerve, genitofemoral nerve, femoral nerve, lateral femoral cutaneous nerve, and obturator nerve (figure 2).

The femoral nerve (L2 to L4) runs through the psoas muscle and emerges at the lower border between the psoas and iliacus muscles, beneath the inguinal ligament lateral to the common femoral artery. The femoral nerve provides motor branches to thigh extensors and sensation to the anterior thigh, femur, knee joint, and medial leg (figure 3 and figure 4). The saphenous nerve is the terminal sensory branch of the femoral nerve.

To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information on subscription options, click below on the option that best describes you:

Subscribers log in here

Literature review current through: Nov 2017. | This topic last updated: Nov 08, 2017.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2017 UpToDate, Inc.
  1. Brown DL. Psoas compartment block. In: Atlas of Regional Anesthesia, 2nd ed, Brown DL (Ed), WB Saunders Company, Philadelphia 1999. p.88-91.
  2. Touray ST, de Leeuw MA, Zuurmond WW, Perez RS. Psoas compartment block for lower extremity surgery: a meta-analysis. Br J Anaesth 2008; 101:750.
  3. Pusch F, Wildling E, Klimscha W, Weinstabl C. Sonographic measurement of needle insertion depth in paravertebral blocks in women. Br J Anaesth 2000; 85:841.
  4. Weller RS, Gerancher JC, Crews JC, Wade KL. Extensive retroperitoneal hematoma without neurologic deficit in two patients who underwent lumbar plexus block and were later anticoagulated. Anesthesiology 2003; 98:581.
  5. Klein SM, D'Ercole F, Greengrass RA, Warner DS. Enoxaparin associated with psoas hematoma and lumbar plexopathy after lumbar plexus block. Anesthesiology 1997; 87:1576.
  6. Horlocker TT, Wedel DJ, Rowlingson JC, et al. Regional anesthesia in the patient receiving antithrombotic or thrombolytic therapy: American Society of Regional Anesthesia and Pain Medicine Evidence-Based Guidelines (Third Edition). Reg Anesth Pain Med 2010; 35:64.
  7. Ritter JW. Femoral nerve "sheath" for inguinal paravascular lumbar plexus block is not found in human cadavers. J Clin Anesth 1995; 7:470.
  8. Parkinson SK, Mueller JB, Little WL, Bailey SL. Extent of blockade with various approaches to the lumbar plexus. Anesth Analg 1989; 68:243.
  9. Brindenbaugh PO, Wedel DJ. The lower extremity: Somatic blockade. In: Cousins and Bridenbaugh's Neural Blockade in Clinical Anaesthesia and Management of Pain, Cousins MJ, Brindenbaugh PO (Eds), Lippincott-Raven, Philadelphia 1998. p.373.
  10. Atanassoff PG, Weiss BM, Brull SJ, et al. Electromyographic comparison of obturator nerve block to three-in-one block. Anesth Analg 1995; 81:529.
  11. Seeberger MD, Urwyler A. Paravascular lumbar plexus block: block extension after femoral nerve stimulation and injection of 20 vs. 40 ml mepivacaine 10 mg/ml. Acta Anaesthesiol Scand 1995; 39:769.
  12. Bomberg H, Huth A, Wagenpfeil S, et al. Psoas Versus Femoral Blocks: A Registry Analysis of Risks and Benefits. Reg Anesth Pain Med 2017; 42:719.
  13. Aveline C, Le Hetet H, Le Roux A, et al. Perineural ultrasound-guided catheter bacterial colonization: a prospective evaluation in 747 cases. Reg Anesth Pain Med 2011; 36:579.
  14. Cuvillon P, Ripart J, Lalourcey L, et al. The continuous femoral nerve block catheter for postoperative analgesia: bacterial colonization, infectious rate and adverse effects. Anesth Analg 2001; 93:1045.
  15. Capdevila X, Bringuier S, Borgeat A. Infectious risk of continuous peripheral nerve blocks. Anesthesiology 2009; 110:182.
  16. Hebbard P, Ivanusic J, Sha S. Ultrasound-guided supra-inguinal fascia iliaca block: a cadaveric evaluation of a novel approach. Anaesthesia 2011; 66:300.
  17. Dolan J, Williams A, Murney E, et al. Ultrasound guided fascia iliaca block: a comparison with the loss of resistance technique. Reg Anesth Pain Med 2008; 33:526.
  18. Markman B, Barton FE Jr. Anatomy of the subcutaneous tissue of the trunk and lower extremity. Plast Reconstr Surg 1987; 80:248.
  19. Ota J, Sakura S, Hara K, Saito Y. Ultrasound-guided anterior approach to sciatic nerve block: a comparison with the posterior approach. Anesth Analg 2009; 108:660.
  20. Barbero C, Fuzier R, Samii K. Anterior approach to the sciatic nerve block: adaptation to the patient's height. Anesth Analg 2004; 98:1785.
  21. Singelyn FJ, Aye F, Gouverneur JM. Continuous popliteal sciatic nerve block: an original technique to provide postoperative analgesia after foot surgery. Anesth Analg 1997; 84:383.
  22. Chan VW, Nova H, Abbas S, et al. Ultrasound examination and localization of the sciatic nerve: a volunteer study. Anesthesiology 2006; 104:309.
  23. Graif M, Seton A, Nerubai J, et al. Sciatic nerve: sonographic evaluation and anatomic-pathologic considerations. Radiology 1991; 181:405.
  24. Labat G. Regional Anesthesia: Its Technique and Clinical Applications, 2nd ed, WB Saunders, Philadelphia 1928. p.45.
  25. Perlas A, Brull R, Chan VW, et al. Ultrasound guidance improves the success of sciatic nerve block at the popliteal fossa. Reg Anesth Pain Med 2008; 33:259.
  26. Danelli G, Fanelli A, Ghisi D, et al. Ultrasound vs nerve stimulation multiple injection technique for posterior popliteal sciatic nerve block. Anaesthesia 2009; 64:638.
  27. Karmakar MK, Shariat AN, Pangthipampai P, Chen J. High-definition ultrasound imaging defines the paraneural sheath and the fascial compartments surrounding the sciatic nerve at the popliteal fossa. Reg Anesth Pain Med 2013; 38:447.
  28. Krombach J, Gray AT. Sonography for saphenous nerve block near the adductor canal. Reg Anesth Pain Med 2007; 32:369.
  29. Gray AT, Collins AB. Ultrasound-guided saphenous nerve block. Reg Anesth Pain Med 2003; 28:148; author reply 148.
  30. Jaeger P, Nielsen ZJ, Henningsen MH, et al. Adductor canal block versus femoral nerve block and quadriceps strength: a randomized, double-blind, placebo-controlled, crossover study in healthy volunteers. Anesthesiology 2013; 118:409.
  31. Kwofie MK, Shastri UD, Gadsden JC, et al. The effects of ultrasound-guided adductor canal block versus femoral nerve block on quadriceps strength and fall risk: a blinded, randomized trial of volunteers. Reg Anesth Pain Med 2013; 38:321.
  32. Davis JJ, Bond TS, Swenson JD. Adductor canal block: more than just the saphenous nerve? Reg Anesth Pain Med 2009; 34:618.
  33. Abdallah FW, Whelan DB, Chan VW, et al. Adductor Canal Block Provides Noninferior Analgesia and Superior Quadriceps Strength Compared with Femoral Nerve Block in Anterior Cruciate Ligament Reconstruction. Anesthesiology 2016; 124:1053.
  34. Chen J, Lesser JB, Hadzic A, et al. Adductor canal block can result in motor block of the quadriceps muscle. Reg Anesth Pain Med 2014; 39:170.
  35. Redborg KE, Sites BD, Chinn CD, et al. Ultrasound improves the success rate of a sural nerve block at the ankle. Reg Anesth Pain Med 2009; 34:24.
Topic Outline