title: Motor nerve injuries following the minimally invasive lateral transpsoas approach.
abstract: OBJECTIVE
  The aim of this study was to determine the incidence of motor nerve injuries during the minimally invasive lateral interbody fusion procedure at a single academic medical center.
  
  
  METHODS
  A retrospective chart review of 118 patients who had undergone lateral interbody fusion was performed. Both inpatient and outpatient records were examined to identify any new postoperative motor weakness in the lower extremities and abdominal wall musculature that was attributable to the operative procedure.
  
  
  RESULTS
  In the period from 2007 to 2011 the lateral interbody fusion procedure was attempted on 201 lumbar intervertebral disc levels. No femoral nerve injuries occurred at any disc level other than the L4-5 disc space. Among procedures involving the L4-5 level there were 2 femoral nerve injuries, corresponding to a 4.8% injury risk at this level as compared with a 0% injury risk at other lumbar spine levels. Five patients (4.2%) had postoperative abdominal flank bulge attributable to injury to the abdominal wall motor innervation.
  
  
  CONCLUSIONS
  The overall incidence of femoral nerve injury after the lateral transpsoas approach was 1.7%; however, the level-specific incidence was 4.8% for procedures performed at the L4-5 disc space. Approximately 4% of patients had postoperative abdominal flank bulge. Surgeons will be able to minimize these motor nerve injuries through judicious use of the procedure at the L4-5 level and careful attention to the T-11 and T-12 motor nerves during exposure and closure of the abdominal wall.
authors: Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, Florida 33136, USA.
authors: Kevin S
authors: KS
authors: Cahill
authors: Joseph L
authors: JL
authors: Martinez
authors: Michael Y
authors: MY
authors: Wang
authors: Steven
authors: S
authors: Vanni
authors: Allan D
authors: AD
authors: Levi
mesh_terms: D034861:Abdominal Wall / Q000294:innervation*; D000046:Academic Medical Centers; D000368:Aged; D004576:Electromyography; D005260:Female; D005267:Femoral Nerve / Q000293:injuries; D006801:Humans; D007431:Intraoperative Complications / Q000209:etiology*; D007866:Leg / Q000294:innervation*; D008159:Lumbar Vertebrae / Q000293:injuries*; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000009:adverse effects*; D009046:Motor Neurons; D018908:Muscle Weakness / Q000209:etiology*; D059348:Peripheral Nerve Injuries / Q000209:etiology*; D016658:Psoas Muscles / Q000294:innervation* / Q000601:surgery*; D012189:Retrospective Studies; D013122:Spinal Diseases / Q000601:surgery*; D013123:Spinal Fusion / Q000009:adverse effects*