title: Lack of relationship between occupational workload and microscopic alterations in lumbar intervertebral disc disease.
abstract: OBJECTIVE
  The study investigated the impact of occupational workloads on disc surgery specimens. We report the relationship between workload and histological features.
  
  
  METHODS
  Specimens were collected prospectively from patients suffering from lumbar disc prolapse (n=90) or spinal osteochondrosis (n=19). Histomorphology and occupational workload data and histomorphological features were evaluated. Occupational data were collected in a structured, standardized patient interview assessing lifting and carrying loads. In this way the exposure was assessed for each test subject's entire working life up to surgery.
  
  
  RESULTS
  There was no association between cumulative workload and histological patterns. In a subgroup of patients with a workload period of 12 months prior to surgery a relevant formation of chondrocyte clusters (p=0.055) was apparent. Chondrocyte cluster formation was found in 83% (n=74) of the prolapse patients and in 58% (n=11) of the osteochondrosis patients (p=0.02). Fibrocyte mediated scar formation was found in 55% of the prolapse patients and in 45% of the spinal stenosis patients. Chondrocyte clusters and their de novo collagen matrix did not integrate biomechanically sufficient with collagen fibers of the disc. Disintegration of clusters from disc matrix and formation of intra-discal sequesters were observed.
  
  
  CONCLUSIONS
  Matrix degeneration was common but displayed no relationship to occupational workload or other histological features. Scar formation was observed in every second specimen. Regenerative chondrocyte cluster proliferation was a common feature in disc specimens and tended to be associated in patients with a workload one year before surgery.
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, Medical Faculty, University of Leipzig, Germany.
authors.forename: Gerald
authors.initials: G
authors.lastname: Huschak
authors.affiliation: Department of Pathology, Martin Luther University, Medical Faculty, Halle, Germany.
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Holzhausen
authors.affiliation: Spine Center Baden, Mittelbaden Hospital, Baden-Baden, Germany.
authors.forename: Andre
authors.initials: A
authors.lastname: Beier
authors.affiliation: Department of Neurosurgery, Bergmannstrost Hospital, Halle, Germany.
authors.forename: Hans Jörg
authors.initials: HJ
authors.lastname: Meisel
authors.affiliation: Spine Center Baden, Mittelbaden Hospital, Baden-Baden, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Hoell
keywords: Chondrocyte proliferation; degeneration; histology; intra-discal scar formation; lumbar disc disease; workload.