title: Recovery of muscle strength after microdiscectomy for lumbar disc herniation: a prospective cohort study with 1-year follow-up.
abstract: BACKGROUND
  Surgery has not been proven to be a better treatment option than non-operative management for limb paresis due to lumbar disc herniation. For the patients it will still be a concern, whether they will regain full strength after the operation or not.
  
  
  METHODS
  A prospective cohort study of 91 patients with preoperative paresis due to disc herniation with 1-year follow up was carried out. The primary outcome was muscle strength in affected limb, and the secondary outcome was self-reported symptoms on back and leg pain, disability, health related quality of life, general health and working capability.
  
  
  RESULTS
  Seventy-five percent of patients had no paresis 1 year after the operation. The severity of the paresis was the only predictor for persistent paresis. Preoperative duration of the paresis did not influence the rate of full recovery. Non-recovery was associated with inferior outcomes and higher risk for reduced working capability.
  
  
  CONCLUSIONS
  The majority of patients with paresis were fully recovered 1 year after microdiscectomy for lumbar disc herniation. If the paresis was severe at baseline, there was a four times higher risk for non-recovery. Patients who did not recover had significantly worse outcomes.
authors.affiliation: Department of Orthopaedic Surgery, Innlandet Hospital Trust, Anders Sandvigsgt 17, Lillehammer, 2609, Norway. greger.lonne@ntnu.no
authors.forename: Greger
authors.initials: G
authors.lastname: Lønne
authors.forename: Tore K
authors.initials: TK
authors.lastname: Solberg
authors.forename: Kristin
authors.initials: K
authors.lastname: Sjaavik
authors.forename: Øystein P
authors.initials: ØP
authors.lastname: Nygaard
mesh_terms: D000328:Adult; D001416:Back Pain / Q000453:epidemiology; D015331:Cohort Studies; D004185:Disability Evaluation; D017586:Diskectomy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000601:surgery*; D008137:Longitudinal Studies; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D010291:Paresis / Q000453:epidemiology; D015995:Prevalence; D011446:Prospective Studies; D011788:Quality of Life; D020127:Recovery of Function / Q000502:physiology*; D016896:Treatment Outcome