title: Association between muscle function and low back pain in relation to pregnancy.
abstract: OBJECTIVE
  To investigate the association of muscle function and subgroups of low back pain (no low back pain, pelvic girdle pain, lumbar pain and combined pelvic girdle pain and lumbar pain) in relation to pregnancy.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Consecutively enrolled pregnant women seen in gestational weeks 12-18 (n = 301) and 3 months postpartum (n = 262).
  
  
  METHODS
  Classification into subgroups by means of mechanical assessment of the lumbar spine, pelvic pain provocation tests, standard history and a pain drawing. Trunk muscle endurance, hip muscle strength (dynamometer) and gait speed were investigated.
  
  
  RESULTS
  In pregnancy 116 women had no low back pain, 33% (n = 99) had pelvic girdle pain, 11% (n = 32) had lumbar pain and 18% (n = 54) had combined pelvic girdle pain and lumbar pain. The prevalence of pelvic girdle pain/combined pelvic girdle pain and lumbar pain decreased postpartum, whereas the prevalence of lumbar pain remained stable. Women with pelvic girdle pain and/or combined pelvic girdle pain and lumbar pain had lower values for trunk muscle endurance, hip extension and gait speed as compared to women without low back pain in pregnancy and postpartum (p < 0.001-0.04). Women with pelvic girdle pain throughout the study had lower values of back flexor endurance compared with women without low back pain.
  
  
  CONCLUSIONS
  Muscle dysfunction was associated with pelvic girdle pain, which should be taken into consideration when developing treatment strategies and preventive measures.
authors.affiliation: Department of Medicine and Health Sciences, Division of Physiotherapy, Linköping University, Linköping, Sweden. annelie.gutke@ihs.liu.se
authors.forename: Annelie
authors.initials: A
authors.lastname: Gutke
authors.forename: Hans Christian
authors.initials: HC
authors.lastname: Ostgaard
authors.forename: Birgitta
authors.initials: B
authors.lastname: Oberg
mesh_terms: D000293:Adolescent; D000328:Adult; D015331:Cohort Studies; D005260:Female; D005684:Gait / Q000502:physiology; D006615:Hip; D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology*; D008159:Lumbar Vertebrae; D009119:Muscle Contraction / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology*; D017699:Pelvic Pain / Q000503:physiopathology*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000503:physiopathology*; D011446:Prospective Studies; D011644:Puerperal Disorders / Q000503:physiopathology*