title: Lumbar paraspinal muscle function, perception of lumbar position, and postural control in disc herniation-related back pain.
abstract: METHODS
  A follow-up study evaluating postural control, lumbar movement perception, and paraspinal muscle reflexes in disc herniation-related chronic low back pain (LBP) before and after discectomy.
  
  
  OBJECTIVE
  To assess the effect of discectomy on postural control, lumbar perception, and reflex activation of paraspinal muscles during sudden upper limb loading.
  
  
  BACKGROUND
  Impaired muscle function, postural control, and lumbar proprioception have been observed in LBP. However, they have not been studied in sciatica patients after surgery.
  
  
  METHODS
  The study included 20 patients selected for an operation for chronic LBP caused by disc herniation and 15 controls without chronic LBP. The paraspinal muscle responses for upper limb loading during unexpected and expected conditions were measured by surface electromyography. The ability to sense lumbar rotation was assessed in a previously validated motorized trunk rotation unit in the seated position. The postural control was measured with a vertical force platform. Pain, disability, and depression scores were recorded.
  
  
  RESULTS
  Patients had poorer lumbar perception (P = 0.012) and postural control (P < 0.05) than did healthy controls. The postural control remained unchanged, but lumbar perception (P = 0.054) and the lumbar feed-forward control (P = 0.043) improved after the surgery.
  
  
  CONCLUSIONS
  The results demonstrate impaired lumbar proprioception and postural control in sciatica patients. During short-term follow-up after operative treatment, postural control does not seem to change, but impaired lumbar proprioception and feed-forward control of paraspinal muscles seem to recover.
authors.affiliation: Department of Physical and Rehabilitation Medicine, Kuopio University Hospital, Kuopio, Finland. ville.leinonen@kuh.fi
authors.forename: Ville
authors.initials: V
authors.lastname: Leinonen
authors.forename: Markku
authors.initials: M
authors.lastname: Kankaanpää
authors.forename: Matti
authors.initials: M
authors.lastname: Luukkonen
authors.forename: Martti
authors.initials: M
authors.lastname: Kansanen
authors.forename: Osmo
authors.initials: O
authors.lastname: Hänninen
authors.forename: Olavi
authors.initials: O
authors.lastname: Airaksinen
authors.forename: Simo
authors.initials: S
authors.lastname: Taimela
mesh_terms: D002908:Chronic Disease; D017586:Diskectomy; D004576:Electromyography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000503:physiopathology* / Q000601:surgery; D017116:Low Back Pain / Q000209:etiology / Q000503:physiopathology*; D008161:Lumbosacral Region; D008297:Male; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010147:Pain Measurement; D011187:Posture / Q000502:physiology; D011434:Proprioception / Q000502:physiology; D012018:Reflex / Q000502:physiology; D012585:Sciatica / Q000209:etiology / Q000503:physiopathology; D013131:Spine / Q000503:physiopathology*; D014102:Torsion Abnormality; D016896:Treatment Outcome; D034941:Upper Extremity / Q000502:physiology; D016474:Weight-Bearing / Q000502:physiology