title: Predictors of walking performance and walking capacity in people with lumbar spinal stenosis, low back pain, and asymptomatic controls.
abstract: OBJECTIVE
  To examine predictors of community walking performance and walking capacity in people with lumbar spinal stenosis (LSS), compared with people with low back pain and asymptomatic control subjects.
  
  
  METHODS
  Retrospective analysis.
  
  
  METHODS
  University spine program.
  
  
  METHODS
  Participants (N=126; 50 LSS, 44 low back pain, 32 asymptomatic control subjects) aged 55 to 80 years were studied.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Seven-day community walking distance measured by pedometer (walking performance) and a 15-minute walking test (walking capacity). All participants had lumbosacral magnetic resonance imaging, electrodiagnostic testing, and a history and physical examination, including a history of pain and neurologic symptoms, a straight leg raise test, and tests for directional symptoms, reflexes, strength, and nerve tension signs. The study questionnaire included demographic information, a history of back/leg pain, and questions about walking, exercise frequency, and pain level, as well as the standardized Quebec Back Pain Disability Scale.
  
  
  RESULTS
  Body mass index (BMI), pain, age, and female sex predicted walking performance (r(2)=.41) and walking capacity (r(2)=.41). The diagnosis of LSS itself had no clear relationship with either walking variable. Compared with the asymptomatic group, LSS participants had significantly lower values for all walking parameters, with the exception of stride length, while there was no significant difference between the LSS and low back pain groups.
  
  
  CONCLUSIONS
  BMI, pain, female sex, and age predict walking performance and capacity in people with LSS, those with low back pain, and asymptomatic control subjects. While pain was the strongest predictor of walking capacity, BMI was the strongest predictor of walking performance. Average pain, rather than leg pain, was predictive of walking performance and capacity. Obesity and pain are modifiable predictors of walking deficits that could be targets for future intervention studies aimed at increasing walking performance and capacity in both the low back pain and LSS populations.
authors.affiliation: University of Michigan Spine Program, Ann Arbor, MI, USA. ctomkins@mtroyal.ca
authors.forename: Christy C
authors.initials: CC
authors.lastname: Tomkins-Lane
authors.forename: Sara Christensen
authors.initials: SC
authors.lastname: Holz
authors.forename: Karen S
authors.initials: KS
authors.lastname: Yamakawa
authors.forename: Vaishali V
authors.initials: VV
authors.lastname: Phalke
authors.forename: Doug J
authors.initials: DJ
authors.lastname: Quint
authors.forename: Jennifer
authors.initials: J
authors.lastname: Miner
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Haig
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D015992:Body Mass Index; D016022:Case-Control Studies; D004185:Disability Evaluation; D004576:Electromyography; D005260:Female; D006801:Humans; D016014:Linear Models; D017116:Low Back Pain / Q000503:physiopathology*; D008159:Lumbar Vertebrae / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008824:Michigan; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology; D010147:Pain Measurement; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D013130:Spinal Stenosis / Q000503:physiopathology*; D011795:Surveys and Questionnaires; D016138:Walking / Q000502:physiology*