title: The Influence of Centralization and Directional Preference on Spinal Control in Patients With Nonspecific Low Back Pain.
abstract: METHODS
  Prospective cohort, test-retest design.
  
  
  BACKGROUND
  Directional preference (DP) with centralization (CEN) and DP without CEN are common pain-pattern responses assessed by Mechanical Diagnosis and Therapy (MDT). Although there is evidence that MDT can reduce pain and disability in the short term by treating the patient with direction-specific exercises concordant with the patient's DP, the mechanism responsible for this is unclear.
  
  
  OBJECTIVE
  To determine whether clinical signs of impaired spinal control improve immediately after eliciting a DP-with-CEN response or a DP-without-CEN response in patients with nonspecific low back pain.
  
  
  METHODS
  Participants underwent a standardized MDT assessment and were classified into the following pain-pattern subgroups: DP with CEN, DP without CEN, or no DP. Clinical signs of impaired spinal control were assessed pre-MDT assessment and post-MDT assessment by an independent examiner. Four spinal control tests were conducted: aberrant lumbar movements while bending forward, the active straight leg raise (ASLR) test, the Trendelenburg test, and the prone instability test. Differences in spinal control pre-MDT assessment and post-MDT assessment were calculated for the 3 pain-pattern subgroups and compared with chi-square tests. We hypothesized that a larger proportion of patients in the DP-with-CEN subgroup would exhibit improved spinal control than patients categorized as DP without CEN or no DP.
  
  
  RESULTS
  Of 114 patients recruited, 51 patients (44.7%) were categorized as DP with CEN, 23 (20.2%) as DP without CEN, and 40 (35.1%) as no DP. Before MDT assessment, between 28.9% (Trendelenburg test) and 63.7% (ASLR test) of patients showed impaired spinal control. After MDT assessment, a larger proportion of patients in the DP-with-CEN subgroup (43%) showed improvement than those in the no-DP subgroup (7%) on aberrant lumbar movements (P = .02). Likewise, more patients in the DP-with-CEN subgroup (50%) improved on the ASLR test than those in the no-DP subgroup (8%, P<.01) or the DP-without-CEN subgroup (7%, P = .01). Changes in Trendelenburg test and prone instability test outcomes did not reach statistical significance.
  
  
  CONCLUSIONS
  Immediately following MDT assessment, a larger proportion of patients with a DP-with-CEN pain pattern showed improvement in clinical signs of spinal control compared to patients with a DP-without-CEN or no-DP pain pattern. The current study was registered in the Dutch trial registry at http://www.trialregister.nl/trialreg/index.asp (NTR4246).
  
  
  METHODS
  Therapy, level 2b.
authors.forename: Adri T
authors.initials: AT
authors.lastname: Apeldoorn
authors.forename: Hans
authors.initials: H
authors.lastname: van Helvoirt
authors.forename: Hanneke
authors.initials: H
authors.lastname: Meihuizen
authors.forename: Henk
authors.initials: H
authors.lastname: Tempelman
authors.forename: David
authors.initials: D
authors.lastname: Vandeput
authors.forename: Dirk L
authors.initials: DL
authors.lastname: Knol
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Kamper
authors.forename: Raymond W
authors.initials: RW
authors.lastname: Ostelo
mesh_terms: D000328:Adult; D005081:Exercise Therapy; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D008159:Lumbar Vertebrae / Q000503:physiopathology*; D008297:Male; D011446:Prospective Studies; D016059:Range of Motion, Articular
keywords: Mechanical Diagnosis and Therapy; motor control; physical therapy