title: Scientific basis of minimally invasive spine surgery: prevention of multifidus muscle injury during posterior lumbar surgery.
abstract: METHODS
  Literature review.
  
  
  OBJECTIVE
  To describe the scientific basis of minimally invasive spine surgery as it relates to posterior lumbar surgery.
  
  
  BACKGROUND
  Minimally invasive spine (MIS) surgery is predicated on several basic principles: (1) avoid muscle crush injury by self-retaining retractors; (2) do not disrupt tendon attachment sites of key muscles, particularly the origin of the multifidus muscle at the spinous process; (3) use known anatomic neurovascular and muscle compartment planes; and (4) minimize collateral soft tissue injury by limiting the width of the surgical corridor.
  
  
  METHODS
  Literature review.
  
  
  RESULTS
  The conventional midline posterior approach for lumbar decompression and fusion violates these key principles of MIS surgery. The tendon origin of the multifidus muscle is detached, the surgical corridor is exceedingly wide, and significant muscle crush injury occurs through the use of powerful self-retaining retractors. The combination of these events leads to well-described changes in muscle physiology and function. MIS surgery is performed using table-mounted tubular retractors that focus the surgical dissection to a narrow corridor directly over the surgical target site. The path of the surgical corridor is selected on the basis of anatomic planes, specifically avoiding injury to the musculotendinous complex and the neurovascular bundle.
  
  
  CONCLUSIONS
  With these relatively simple modifications to surgical technique, significant improvements in intraoperative blood loss, postoperative pain, surgical morbidity, return of function, among others, have been achieved. However, MIS techniques remain technically demanding and a significant complication rate has been observed during the initial learning curve of the procedures.
authors.affiliation: Spine Institute of San Diego, Center for Minimally Invasive Spine Surgery at Alvarado Hospital, San Diego, CA, USA. chollkim@smiss.org
authors.forename: Choll W
authors.initials: CW
authors.lastname: Kim
mesh_terms: D019299:Decompression, Surgical / Q000009:adverse effects / Q000379:methods*; D006801:Humans; D007431:Intraoperative Complications / Q000517:prevention & control*; D008159:Lumbar Vertebrae / Q000601:surgery*; D019060:Minimally Invasive Surgical Procedures / Q000009:adverse effects / Q000379:methods*; D018482:Muscle, Skeletal / Q000293:injuries; D013123:Spinal Fusion / Q000009:adverse effects / Q000379:methods*