From The Ergoweb® Learning Center

Study: Lengthy Disability Seen in Carpal Tunnel Syndrome Cases

Approximately 63% of workers diagnosed with industrial-related carpal tunnel syndrome (CTS) received compensation for lost work time according to a recent retrospective study involving state of Washington employees.  Among those with lost work time (8,224 subjects), about half had more than three months while one-quarter had more than 12 months of paid disability.  The average duration of cumulative compensatory lost work time was 3.6 months.

The study found that the cumulative duration of compensated lost work days was slightly longer for workers who had surgery than for those who did not.  However, when surgical treatment was applied to select cases, fewer lost work days occurred.  The characteristics of those cases included:

  • CTS was diagnosed at the time the claim was filed or shortly thereafter
  • Surgery was performed relatively quickly (no later than 6 months after filing)
  • The worker’s condition was not complicated by concurrent disorders
  • Both the diagnosing and surgical physician(s) had a great amount of experience with CTS claims

This four year study (cases from 1990-1994 with follow up to 2000) found a lower probability of returning to work by 6 months when the worker received physical/rehabilitation treatment.  However, disability compensation was provided to 94% of the cases where CTS surgery was performed while to only 40% of the cases that did not undergo CTS surgery.   

The Bottom Line – How This Applies To Ergonomists
This study identified the great costs that work-related carpal tunnel syndrome can generate to cover treatment, permanent disability, and time-loss liabilities.  Although no mention was made to ergonomic worksite modifications, there are numerous solutions to reduce pressure/irritation of the median nerve.  A cost-conscious company or insurance carrier, when informed of overlooked options, will see the benefits of an ergonomic analysis in promoting a return to work of the employee who has carpal tunnel syndrome. Better yet, companies armed with this knowledge could use it to justify a proactive approach to ergonomics in which risk factors are understood and eliminated or reduced through process and workplace design.

Other Key Study Points
Of those with CTS and lost work time, 41% were awarded a permanent partial disability (PPD) settlement.  Workers who underwent surgery had a higher incidence of PPD (46%) compared to workers who followed conservative management (32%).

The incidence of time-loss CTS based on occupation occurred in the following manner:

  • 33% – operators, fabricators, and laborers
  • 23% – white collar workers
  • 15% – service employees
  • 11% – precision production and repair craftsmen
  • 11% – construction workers
  • 4% – farming, forestry or fishing employees
  • 3% – other workers

Study Method
Administrative data was acquired from the Washington State Department of Labor and Industries (DLI) workers’ compensation claims for carpal tunnel syndrome filed during 1990-1994 and followed through 2000.  In the state of Washington, the DLI provides workers’ compensation coverage for approximately two-thirds of all non-federal employees within the state.

Subject inclusion criteria included:

  • Worker was covered by DLI provided workers’ compensation insurance
  • A claim was filed between January 1, 1990 and December 31, 1994
  • The claim was accepted as work-related
  • A paid billing had an International Classification of Disease code for CTS or median nerve neuropathy or Current Procedural Terminology code for open or arthroscopic carpal tunnel surgery
  • CTS was diagnosed between one before and twelve months after the report of the claim
  • Receipt of lost work compensation due to the CTS condition
  • No other lost time workers’ compensation claims 

Data of concern involved claimant demographics, employment characteristics, clinical features of the disorder, and DLI administrative information.

This complete paper can be acquired at:
http://www3.interscience.wiley.com/journal/122665777/abstract

Article Title: Work-Related Carpal Tunnel Syndrome in Washington State Workers’ Compensation: Utilization of Surgery and the Duration of Lost Work

Publication: American Journal of Industrial Medicine, 52:931-942, 2009

Authors: W E Daniell, D Fulton-Kehoe, and G M Franklin

This article originally appeared in The Ergonomics Report™ on 2010-01-04.