title: Percutaneous transforaminal lumbar interbody fusion for the treatment of degenerative lumbar instability.
abstract: OBJECTIVE
  Percutaneous spinal instrumentation techniques may be helpful to reduce approach-related morbidity inherent to conventional open surgery. This article reports technique, clinical outcomes, and fusion rates of percutaneous transforaminal lumbar interbody fixation (pTLIF). Results are compared with those of mini-open transforaminal lumbar interbody fixation (oTLIF) using a muscle splitting (Wiltse) approach.
  
  
  METHODS
  pTLIF was performed in 43 patients with single-level and 10 patients with bi- or multilevel lumbar discopathy or degenerative pseudolisthesis resulting in axial back pain and claudication, pseudoradicular, or radicular symptoms. Decompression, discectomy, and interbody cage insertion were performed through 18-mm tubular retractors followed by percutaneous pedicle screw-rod fixation. Clinical outcome was assessed by early postoperative pain scores (visual analog score) and standardized functional outcome questionnaires (American Academy of Orthopedic Surgeons lumbar spine and Roland-Morris low back pain score). Fusion rates were assessed by thin-slice computed tomographic scan at 16 months. Clinical outcome, time in the operating room, intraoperative blood loss, and postoperative access-site pain were compared with an institutional reference series of 67 oTLIF procedures.
  
  
  RESULTS
  Excellent and good clinical results were obtained in 46 (87%) out of 53 patients at 16 months. The time spent in the operating room was equivalent and the blood loss reduced compared with oTLIF (P < 0.01). There was no morbidity related to instrumentation. Postoperative pain was significantly lower after pTLIF after the second postoperative day (P < 0.01). The overall clinical outcome was not different from oTLIF at 8 and 16 months.
  
  
  CONCLUSIONS
  pTLIF allows for safe and efficient minimally invasive treatment of single and multilevel degenerative lumbar instability with good clinical results. Further prospective studies investigating long-term functional results are required to assess the definitive merits of percutaneous instrumentation of the lumbar spine.
authors.affiliation: Department of Neurosurgery, University Medical Center Freiburg, Freiburg, Germany. Kai.Scheufler@hirslanden.ch
authors.forename: Kai-Michael
authors.initials: KM
authors.lastname: Scheufler
authors.forename: Hildegard
authors.initials: H
authors.lastname: Dohmen
authors.forename: Vassilios I
authors.initials: VI
authors.lastname: Vougioukas
mesh_terms: D000368:Aged; D015331:Cohort Studies; D019299:Decompression, Surgical / Q000009:adverse effects / Q000379:methods / Q000706:statistics & numerical data; D017587:Diskectomy, Percutaneous / Q000009:adverse effects / Q000379:methods / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000009:adverse effects / Q000379:methods / Q000706:statistics & numerical data; D010147:Pain Measurement; D019736:Prostheses and Implants; D012189:Retrospective Studies; D013122:Spinal Diseases / Q000000981:diagnostic imaging / Q000601:surgery*; D013123:Spinal Fusion / Q000009:adverse effects / Q000379:methods / Q000706:statistics & numerical data; D011795:Surveys and Questionnaires; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome