Published 4/1/2014

Study: Back Surgery Offers Long-Term Societal Benefits

Increased earnings, fewer lost work days for surgical patients

Each year, more than 10 million people in the United States experience back pain. More than 200,000 of these patients undergo surgery to alleviate pain due to a herniated disk—and most of these patients are still in the workforce when they undergo surgery.

Previous studies have found that surgical treatment of lumbar disk herniation is cost effective. The Spine Patient Outcomes Research Trial (SPORT), a prospective multicenter study, for example, showed improved clinical outcomes (less pain, greater physical function, and less disability) for patients who had surgery for lumbar disk herniation relative to those who opted for nonsurgical treatment. Additionally, in the pooled randomized and observational cohorts, SPORT found surgery for lumbar disk herniation to be cost-effective over a 4-year period, at an incremental cost of $43,800 per additional quality-adjusted life-year (QALY), with surgical treatment priced at estimated private-payer levels.

A new study, published in the April issue of The Journal of Clinical Orthopaedics and Related Research (CORR), takes these findings a step further by examining the societal benefits of lumbar disk herniation surgery and the impact on workplace productivity. According to this study, estimated average annual earnings of working patients who undergo surgery are $47,619, compared to $45,694 for patients treated nonsurgically. Therefore, the annual earnings are increased by $1,925 for those patients receiving surgery. Additionally, patients who undergo surgery miss 3 fewer days of work each year as compared to patients who elect nonsurgical treatment.

According to the authors of “Cost-effectiveness of Lumbar Discectomy,” these surgeries are cost-effective and may result in savings to society over the long term by relieving patients’ back pain and enabling patients to return to work on a more productive basis. The study found that, over a 4-year period, surgery resulted in cost offsets of more than $5,000 due to higher earnings for patients receiving surgery.

Anecdotal support
Patient stories on the
ANationInMotion.org website support these findings. For example, terrible back pain following an injury on the field limited lacrosse coach Scott Hiller from coaching, and even made it difficult for him to perform everyday tasks such as walking around the house and holding his children. After nonsurgical treatments were unsuccessful in relieving his pain, Mr. Hiller underwent disk herniation repair surgery and now is able to live a life without back pain.

“Back pain is one of the most common and the most difficult orthopaedic conditions for patients, because both standing and sitting may exacerbate the pain. As a result, whether you do physical labor or sit at a desk, back pain can affect your ability to work,” said Michael F. Schafer, MD, professor of orthopaedic surgery, Northwestern University, and an author of the study.

“Pain from a herniated disk causes the average employee to miss 26 days of work each year and spend 34 days in bed,” continued Dr. Schafer. “Surgery, when appropriate, can lessen the pain, increase productivity, and reduce the number of missed workdays. This study strengthens the body of research that indicates surgery to excise herniated disks can be effective as well as cost-effective for patients.”

Literature review, Markov model
To conduct the study, researchers reviewed literature and used patient-reported outcomes from prior studies. Information on functional limitations, missed workdays, and income was drawn from the National Health Interview Survey and used to estimate the effects of lumbar disk herniation on worker productivity. Models were used to determine the number of missed workdays and household earnings conditional on workers’ level of functional ability in a given year.

According to the authors, “Earnings can be affected by disk herniation in numerous ways. First, employees may not be able to work as many hours (and may need to work part-time instead of full-time). Second, the human capital approach postulates that wages are set equal to a worker’s marginal product. Thus, less productive workers are paid less.”

The collected data were applied to a Markov Decision Model, and direct and indirect costs associated with surgical and continued nonsurgical treatment for a herniated disk were estimated by comparing costs for household income, missed workdays, and disability payments. A private-payer perspective was used to determine direct medical costs and patient out-of-pocket expenses were included in these costs. Success was defined as patients’ satisfaction with the results after treatment.

The researchers found that surgical treatment for disk herniation increases earnings by a mean of $7,154 and results in 8.9 additional missed work days during the 4-year period. “In total,” they write, “changes in earnings and missed work days produced a net surgical cost offset equal to $5,603.” Although surgical patients missed 20 work days immediately after the surgery, thus adding to the cost of the surgery, this may be offset if the productivity benefits persist for a longer period.

“Cost-effectiveness increases if the benefit from surgery persists for a longer period,” they noted. “The surgery generates cost savings if the benefit persists for at least 10 years.”

Authors of the study “How Does Accounting for Worker Productivity Affect the Measured Cost-Effectiveness of Lumbar Discectomy?” include Lane Koenig, PhD; Timothy M. Dall, MS; Qian Gu, PhD; Josh Saavoss, BA; and Michael F. Schafer, MD. The AAOS provided research funding for the study.

Disclosure Information: Dr. Schafer—DePuy, A Johnson & Johnson Company; Medtronic; AAOS Now; Journal of Bone and Joint Surgery – American; Spine. Dr. Koenig—BTG International; Johnson & Johnson. Dr. Gu, Mr. Dall, and Mr. Saavoss—no information.