title: Changes in lumbar multifidus muscle function and nociceptive sensitivity in low back pain patient responders versus non-responders after dry needling treatment.
abstract: BACKGROUND
  Little is known about the physiologic mechanism of dry needling. While some evidence suggests that dry needling may decrease nocioceptive sensitivity and facilitate muscle function, no studies to date have examined these physiologic changes compared to clinical outcomes.
  
  
  OBJECTIVE
  To examine changes in lumbar multifidus (LM) muscle function and nociceptive sensitivity after dry needling in patients with LBP and to determine if such changes differ in patients that exhibit improved disability (responders) and those that do not (non-responders).
  
  
  METHODS
  Quasi-experimental study.
  
  
  METHODS
  Sixty-six volunteers with mechanical LBP (38 men, age = 41.3 ± 9.2 years) completed the study. Ultrasound measurements and pain algometry of the LM were taken at baseline and repeated immediately following dry needling treatment to the LM muscles and after one week. The percent change in muscle thickness from rest to contraction was calculated for each time point to represent muscle function. Pressure pain threshold (PPT) was used to measure nociceptive sensitivity. Participants were dichotomized as responders and non-responders based on whether or not they experienced clinical improvement using the modified Oswestry Disability Index after one week. 2 × 3 mixed-model ANOVA were conducted for group (responders vs. non-responders) by time.
  
  
  RESULTS
  Patient responders exhibited larger improvements in LM muscle contraction and nociceptive sensitivity 1 week, but not immediately, after dry needling than non-responders.
  
  
  CONCLUSIONS
  Our results suggest that there may be lasting and clinically relevant sensorimotor changes that occur in LBP patients that improve with dry needling treatment that partially explain the physiologic mechanism of action.
authors: U.S. Army-Baylor University Doctoral Program in Physical Therapy, San Antonio, TX, USA. Electronic address: shanekoppenhaver@mac.com.
authors: Shane L
authors: SL
authors: Koppenhaver
authors: U.S. Army-Baylor University Doctoral Program in Physical Therapy, San Antonio, TX, USA.
authors: Michael J
authors: MJ
authors: Walker
authors: U.S. Army-Baylor University Doctoral Program in Physical Therapy, San Antonio, TX, USA.
authors: Jonathan
authors: J
authors: Su
authors: U.S. Army-Baylor University Doctoral Program in Physical Therapy, San Antonio, TX, USA.
authors: Jared M
authors: JM
authors: McGowen
authors: U.S. Army-Baylor University Doctoral Program in Physical Therapy, San Antonio, TX, USA.
authors: Lindsey
authors: L
authors: Umlauf
authors: Department of Rehabilitation, Guthrie Ambulatory Health Clinic, Ft. Drum, New York, USA.
authors: Kevin D
authors: KD
authors: Harris
authors: Department of Physical Therapy, University of Scranton, Scranton, PA, USA.
authors: Michael D
authors: MD
authors: Ross
mesh_terms: D015670:Acupuncture Therapy / Q000379:methods*; D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000000981:diagnostic imaging / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D009619:Nociceptors / Q000502:physiology*; D010147:Pain Measurement; D017288:Pain Threshold / Q000502:physiology*; D064170:Paraspinal Muscles / Q000503:physiopathology; D018570:Risk Assessment; D012720:Severity of Illness Index; D017211:Treatment Failure; D016896:Treatment Outcome; D018608:Ultrasonography, Doppler / Q000379:methods
keywords: Acupuncture; Low back pain; Muscle contraction; Ultrasonography