title: Assessment of Anteroposterior Subpedicular Approach and Oblique Scotty Dog Subpedicular Approach for Selective Nerve Root Block.
abstract: BACKGROUND
  The technique used to administer a selective nerve root block (SNRB) varies depending on individual expertise. Both the anteroposterior (AP) subpedicular approach and oblique Scotty dog subpedicular approach are widely practiced. However, the literature does not provide a clear consensus regarding which approach is more suitable. Hence, we decided to analyse the procedural parameters and clinical outcomes following SNRBs using these two approaches.
  
  
  METHODS
  Patients diagnosed with a single lumbar herniated intervertebral disc (HIVD) refractory to conservative management but not willing for immediate surgery were selected for a prospective nonrandomized comparative study. An SNRB was administered as a therapeutic alternative using the AP subpedicular approach in one group (n = 25; mean age, 45 ± 5.4 years) and the oblique Scotty dog subpedicular approach in the other group (n = 22; mean age, 43.8 ± 4.7 years). Results were compared in terms of the duration of the procedure, the number of C-arm exposures, accuracy, pain relief, functional outcome and the duration of relief.
  
  
  RESULTS
  Our results suggest that the oblique Scotty dog subpedicular approach took a significantly longer duration (p= 0.02) and a greater number of C-arm exposures (p= 0.001). But, its accuracy of needle placement was 95.5% compared to only 72% using the AP subpedicular approach (p= 0.03). There was no significant difference in terms of clinical outcomes between these approaches.
  
  
  CONCLUSIONS
  The AP subpedicular approach was simple and facile, but the oblique Scotty dog subpedicular approach was more accurate. However, a brief window period of pain relief was achieved irrespective of the approaching technique used.
authors.affiliation: Department of Orthopaedic Surgery, Melmaruvathur Adhiparasakthi Institute of Medical Sciences and Research, Melmaruvathur, Tamil Nadu, India.
authors.forename: Arun-Kumar
authors.initials: AK
authors.lastname: Kaliya-Perumal
authors.affiliation: Department of Orthopaedic Surgery, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Yu-Cheng
authors.initials: YC
authors.lastname: Yeh
authors.affiliation: Department of Orthopaedic Surgery, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Chi-An
authors.initials: CA
authors.lastname: Luo
authors.affiliation: Universiti Tunku Abdul Rahman, Sungai Long, Malaysia.
authors.forename: Kit-Yang
authors.initials: KY
authors.lastname: Joey-Tan
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000379:methods*; D059408:Pain Management / Q000379:methods*; D011446:Prospective Studies; D015641:Radiography, Interventional / Q000379:methods*; D012585:Sciatica / Q000209:etiology / Q000628:therapy*; D013126:Spinal Nerve Roots
keywords: Intervertebral disc displacement; Nerve root compression; Radiculopathy