title: Obturator nerve anatomy and relevance to one-stage facial reanimation: limitations of a retroperitoneal approach.
abstract: BACKGROUND
  Single-stage facial reanimation with a partial gracilis muscle coapted to the contralateral facial nerve seems an optimal surgical solution yet has not supplanted the two-stage approach. Insufficient obturator nerve length may limit reach to sizable contralateral facial nerve branches (possibly necessitating interposition nerve grafting), compromise optimal muscle positioning, or risk nerve coaptation under tension. This study evaluates whether retroperitoneal obturator nerve dissection would effectively lengthen the nerve, thus obviating the aforementioned limitations.
  
  
  METHODS
  Ten hemifaces and obturator nerves of five cadavers were dissected. Facial measurements included modiolus to contralateral facial nerve branches of sufficient size at the vertical line of the lateral orbital rim. Obturator nerve measurements included gracilis neurovascular hilum to (1) obturator canal entry point (ab), (2) intraobturator canal point where additional adductor branches are inseparable by internal neurolysis (ac), and (3) retroperitoneal point of separation between anterior and posterior obturator branches (ad). Obturator nerve reach for cross-facial nerve coaptation was assessed.
  
  
  RESULTS
  Successful coaptation was achieved with obturator nerve dissection to point b approximately 20 percent of the time, to point c 60 to 70 percent of the time, and to retroperitoneal point d 90 to 100 percent of the time
  
  
  CONCLUSIONS
  Successful coaptation to large contralateral facial nerve branches is feasible in 90 to 100 percent of cases if the entire anterior obturator branch is harvested. However, the increased risk of retroperitoneal dissection and sacrifice of additional adductor branches decreases the viability of this approach. Obturator canal dissection (point c) provides reach in 60 to 70 percent of cases, but short interposition nerve grafting may prove necessary.
authors: Dallas, Texas; and Uppsala, Sweden From the Department of Plastic Surgery, The University of Texas Southwestern Medical Center at Dallas, and the Department of Plastic and Maxillofacial Surgery, Uppsala University Hospital.
authors: Shai
authors: S
authors: Rozen
authors: Andres
authors: A
authors: Rodriguez-Lorenzo
authors: Thorir
authors: T
authors: Audolfsson
authors: Corrine
authors: C
authors: Wong
authors: Angela
authors: A
authors: Cheng
mesh_terms: D002102:Cadaver; D004210:Dissection; D005145:Face / Q000033:anatomy & histology / Q000294:innervation / Q000601:surgery; D005154:Facial Nerve / Q000033:anatomy & histology / Q000601:surgery*; D005158:Facial Paralysis / Q000601:surgery*; D006801:Humans; D018482:Muscle, Skeletal / Q000294:innervation / Q000601:surgery*; D009776:Obturator Nerve / Q000033:anatomy & histology* / Q000637:transplantation*; D009929:Organ Size; D019651:Plastic Surgery Procedures / Q000379:methods*; D020127:Recovery of Function; D012187:Retroperitoneal Space / Q000601:surgery; D020858:Tissue and Organ Harvesting / Q000379:methods
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