Practice Variation Among Surgeons Treating Lumbar Spinal Stenosis in a Single Institution

Paul T. Ogink, MD; Olivier van Wulfften Palthe, MD; Teun Teunis, MD; Christopher M. Bono, MD; Mitchell B. Harris, MD; Joseph H. Schwab, MD, MS; Thomas D. Cha, MD, MBA


Spine. 2019;44(7):510-516. 

In This Article

Abstract and Introduction


Study Design: A retrospective study.

Objective: The aim of this study was to examine practice variation in the treatment of lumbar spinal stenosis and identify targets for reducing variation.

Summary of Background Data: Lumbar spinal stenosis is a degenerative condition susceptible to practice variation. Reducing variation aims to improve quality, increase safety, and lower costs. Establishing differences in surgeons' practices from a single institution can help identify personalized variation.

Methods: We identified adult patients first diagnosed with lumbar spinal stenosis between 2003 and 2015 in three hospitals of the same institution with ICD-9 codes.

We extracted number of office visits, imaging procedures, injections, electromyographies (EMGs), and surgery within the first year after diagnosis; physical therapy within the first 3 months after diagnosis. Multivariable logistic regression was used to identify factors associated with surgery. The coefficient of variation (CV) was calculated to compare the variation in practice.

Results: The 10,858 patients we included had an average of 2.5 visits (±1.9), 1.5 imaging procedures (±2.0), 0.03 EMGs (±0.22), and 0.16 injections (±0.53); 36% had at least one surgical procedure and 32% had physical therapy as part of their care. The CV was smallest for number of visits (19%) and largest for EMG (140%).

Male sex [odds ratio (OR): 1.23, P < 0.001], seeing an additional surgeon (OR: 2.82, P < 0.001), and having an additional spine diagnosis (OR: 3.71, P < 0.001) were independently associated with surgery. Visiting an orthopedic clinic (OR: 0.46, P < 0.001) was independently associated with less surgical interventions than visiting a neurosurgical clinic.

Conclusion: There is widespread variation in the entire spectrum of diagnosis and therapy for lumbar spinal stenosis among surgeons in the same institution. Male gender, seeing an additional surgeon, having an additional spine diagnosis, and visiting a neurosurgery clinic were independently associated with increased surgical intervention. The main target we identified for decreasing variability was the use of diagnostic EMG.

Level of Evidence: 3


Lumbar spinal stenosis is a degenerative condition caused by progressive narrowing of the spinal canal and currently the most frequent indication for back surgery.[1,2]

Although variations in care have been described for many conditions,[3–6] spinal stenosis, along with other lumbar spine conditions, seems to be particularly susceptible to variability due to the range of treatment options and difficulties of surgical selection.[7,8]

Reducing this variation aims to improve quality, increase safety, and lower costs. Birkmeyer et al[9] identified differing opinion among surgeons about indications for surgery and the extent of incorporating patient preferences as the main factors in regional variability, making these potential targets for reducing variability. Conflicting opinions among surgeons have persisted for decades partly due to the wide boundaries of acceptable practice, the lack of applicability of clinical trials and guidelines, and differences in training and expertise.[10,11] Although the role of conflicting views is well-established in regional variation,[7,9] there is paucity in the literature regarding its presence in a single institution. Considering the absence of geographic variability of disease incidence, establishing differences in surgeons' practices from a single institution can help identify more individual targets for reducing variation.

The first aim of this study was to assess variation in care for spinal stenosis in the first year after diagnosis among surgeons within the same institution. The second aim was to determine the factors associated with increased rate of surgery. The third aim was to identify targets for reducing variability.