Effects of Musculoskeletal Surgery Rates on Outcomes

Musculoskeletal (MSK) conditions affect more than half of the U.S. population and account for 1 in 5
healthcare visits. MSK care annual costs exceed $176 billion in direct and $876 billion in indirect
healthcare costs and show large increases in per capita costs. Yet, there is remarkably little Level I
evidence supporting this level of healthcare utilization with little consensus on proper treatment
approaches across MSK conditions. Because of difficulties with randomization and blinding, less than
10% of MSK related-studies are clinical trials, and of the trials, less than 40% meet minimal guidelines.
Thus, it is not surprising that substantial geographic variation exists in the use of invasive and costly
treatments for MSK conditions. Using anecdotes, the popular press suggests that early surgery for new
MSK conditions is overused. Simulation studies suggest that lower utilization rates of treatments not
supported by clinical evidence, like surgery for MSK conditions, can dramatically lower Medicare costs
without sacrificing quality. However, beyond anecdote and simulation studies, there is no evidence
supporting the notion that lower surgery rates for patients with MSK conditions will lower costs and
maintain quality. Lower surgery rates may keep surgery from patients who would benefit little from
surgery. Conversely, lower surgery rates may result in many patients delaying beneficial treatment
causing MSK conditions to worsen and result in poorer outcomes and higher long run costs.
Our approach is to use the documented geographic variation in early surgery rates as natural
experiments and apply instrumental variable estimators to assess the impact of higher rates of early
surgery on outcomes and costs. In addition, we will use charts abstracted for a sample of patients to
measure confounders unmeasured in Medicare claims to assess the assumptions underlying our
natural experiment. We will then carefully interpret our estimates considering the outcomes measured
and the validity of the assumptions associated with treatment effect heterogeneity and confounding.
The investigative team has substantial experience assessing treatment effectiveness using Medicare
data and a strong MSK clinical and empirical background. This study builds on our shoulder-related
research using Medicare data from 2011. It will identify important relationships between early surgery
choice, treatment success and costs for patients with MSK conditions. AHRQ has authority to conduct
and support research to reflect the needs and priorities of the Medicare program. This research will
provide key evidence for policy makers to assess whether early surgery for these MSK conditions are over
or underused in practice for Medicare patients. Our study goals align with AHRQ’s goal of “producing
evidence that can be used to increase the affordability and efficiency of health care”.
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Grant Number: 5R01HS027177-04
NIH Institute/Center: AHRQ
Principal Investigator: JOHN BROOKS