title: Outcomes of acute and chronic patients with magnetic resonance imaging-confirmed symptomatic lumbar disc herniations receiving high-velocity, low-amplitude, spinal manipulative therapy: a prospective observational cohort study with one-year follow-up.
abstract: OBJECTIVE
  The purposes of this study were to evaluate patients with low-back pain (LBP) and leg pain due to magnetic resonance imaging-confirmed disc herniation who are treated with high-velocity, low-amplitude spinal manipulation in terms of their short-, medium-, and long-term outcomes of self-reported global impression of change and pain levels at various time points up to 1 year and to determine if outcomes differ between acute and chronic patients using a prospective, cohort design.
  
  
  METHODS
  This prospective cohort outcomes study includes 148 patients (between ages of 18 and 65 years) with LBP, leg pain, and physical examination abnormalities with concordant lumbar disc herniations. Baseline numerical rating scale (NRS) data for LBP, leg pain, and the Oswestry questionnaire were obtained. The specific lumbar spinal manipulation was dependent upon whether the disc herniation was intraforaminal or paramedian as seen on the magnetic resonance images and was performed by a doctor of chiropractic. Outcomes included the patient's global impression of change scale for overall improvement, the NRS for LBP, leg pain, and the Oswestry questionnaire at 2 weeks, 1, 3, and 6 months, and 1 year after the first treatment. The proportion of patients reporting "improvement" on the patient's global impression of change scale was calculated for all patients and acute vs chronic patients. Pretreatment and posttreatment NRS scores were compared using the paired t test. Baseline and follow-up Oswestry scores were compared using the Wilcoxon test. Numerical rating scale and Oswestry scores for acute vs chronic patients were compared using the unpaired t test for NRS scores and the Mann-Whitney U test for Oswestry scores. Logistic regression analysis compared baseline variables with "improvement."
  
  
  RESULTS
  Significant improvement for all outcomes at all time points was reported (P < .0001). At 3 months, 90.5% of patients were "improved" with 88.0% "improved" at 1 year. Although acute patients improved faster by 3 months, 81.8% of chronic patients reported "improvement" with 89.2% "improved" at 1 year. There were no adverse events reported.
  
  
  CONCLUSIONS
  A large percentage of acute and importantly chronic lumbar disc herniation patients treated with chiropractic spinal manipulation reported clinically relevant improvement.
authors.affiliation: Private practice, Zürich, Switzerland.
authors.forename: Serafin
authors.initials: S
authors.lastname: Leemann
authors.affiliation: Professor, Chiropractic Medicine and Radiology departments, Orthopaedic University Hospital Balgrist, University of Zürich, Zürich, Switzerland.. Electronic address: cynthia.peterson@balgrist.ch.
authors.forename: Cynthia K
authors.initials: CK
authors.lastname: Peterson
authors.affiliation: Private practice, Zürich, Switzerland.
authors.forename: Christof
authors.initials: C
authors.lastname: Schmid
authors.affiliation: Private practice, Zürich, Switzerland.
authors.forename: Bernard
authors.initials: B
authors.lastname: Anklin
authors.affiliation: Professor and Chairperson, Chiropractic Medicine Department, Faculty of Medicine, Orthopaedic University Hospital Balgrist, University of Zürich, Zürich, Switzerland.
authors.forename: B Kim
authors.initials: BK
authors.lastname: Humphreys
mesh_terms: D059787:Acute Pain / Q000209:etiology* / Q000628:therapy*; D000293:Adolescent; D000328:Adult; D000368:Aged; D059350:Chronic Pain / Q000209:etiology* / Q000628:therapy*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000150:complications*; D007866:Leg; D017116:Low Back Pain / Q000209:etiology* / Q000628:therapy*; D008279:Magnetic Resonance Imaging; D008297:Male; D020393:Manipulation, Spinal / Q000379:methods*; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
keywords: Chiropractic; Intervertebral Disc Displacement; Lumbar Vertebrae Manipulation, Spinal