title: Lower extremity neuropathies associated with lithotomy positions.
abstract: BACKGROUND
  The goal of this project was to study the frequency and natural history of perioperative lower extremity neuropathies.
  
  
  METHODS
  A prospective evaluation of lower extremity neuropathies in 991 adult patients undergoing general anesthetics and surgical procedures while positioned in lithotomy was performed. Patients were assessed with use of a standard questionnaire and neurologic examination before surgery, daily during hospital stay in the first week after surgery, and by phone if discharged before 1 postoperative week. Patients in whom lower extremity neuropathies developed were observed for 6 months.
  
  
  RESULTS
  Lower extremity neuropathies developed in 15 patients (1.5%; 95% confidence interval, 0.8-2.5%). Unilateral or bilateral nerves were affected in patients as follows: obturator (five patients), lateral femoral cutaneous (four patients), sciatic (three patients), and peroneal (three patients). Paresthesia occurred in 14 of 15 patients, and 4 patients had burning or aching pain. No patient had weakness. Symptoms were noted within 4 h of completion of the anesthetic in all 15 patients. These symptoms resolved within 6 months in 14 of 15 patients. Prolonged positioning in a lithotomy position, especially for more than 2 h, was a major risk factor for this complication (P = 0.006).
  
  
  CONCLUSIONS
  In this surgical population, lower extremity neuropathies were infrequent complications that were noted very soon after surgery and anesthesia. None resulted in prolonged disability. The longer patients were positioned in lithotomy positions, the greater the chance of development of a neuropathy. These findings suggest that a reduction of duration of time in lithotomy positions may reduce the risk of lower extremity neuropathies.
authors.affiliation: Perioperative Outcomes Group (Departments of Anesthesiology and Health Science Research), Mayo Foundation, Rochester, Minnesota, USA. warner.mark@mayo.edu
authors.forename: M A
authors.initials: MA
authors.lastname: Warner
authors.forename: D O
authors.initials: DO
authors.lastname: Warner
authors.forename: C M
authors.initials: CM
authors.lastname: Harper
authors.forename: D R
authors.initials: DR
authors.lastname: Schroeder
authors.forename: P M
authors.initials: PM
authors.lastname: Maxson
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000768:Anesthesia, General; D005260:Female; D013509:Gynecologic Surgical Procedures / Q000009:adverse effects*; D006801:Humans; D007866:Leg / Q000294:innervation*; D008297:Male; D008875:Middle Aged; D010523:Peripheral Nervous System Diseases / Q000209:etiology*; D011187:Posture; D011446:Prospective Studies; D013520:Urologic Surgical Procedures / Q000009:adverse effects*