subjects) had postflight lumbar symptoms (including chronic low
back pain or disc herniation).
CONCLUSIONS: We observed that multifidus atrophy, rather than intervertebral disc swelling, associated strongly with lumbar flattening
and increased stiffness. Because these changes have been previously
linked with detrimental spine biomechanics and pain in terrestrial
populations, when combined with evidence of preflight vertebral
endplate insufficiency, they may elevate injury risk for astronauts
upon return to gravity loading. Our results also have implications
for deconditioned spines on Earth. We anticipate that our results will
inform new astronaut countermeasures that target the multifidus
muscles, and research on the role of muscular stability in relation
to chronic low back pain and disc injury.
Outstanding Paper: Surgical Science
Objective measurement of function following lumbar
spinal stenosis decompression reveals improved functional
capacity with stagnant real-life physical activity
Matthew Smuck, MD; Amir Muaremi, PhD; Patricia Zheng, MD;
Justin Norden, MPhil; Aman Sinha, MPhil; Richard Hu, MD; Christy
BACKGROUND CONTEXT: Lumbar spinal stenosis (LSS) is
a prevalent and costly condition associated with significant
dysfunction. Alleviation of pain and improvement of function are
the primary goals of surgical intervention. While prior studies have
measured subjective improvements in function after surgery, few
have examined objective markers of functional improvement.
PURPOSE: We aimed to objectively measure and quantify changes
in physical capacity and physical performance following surgical
decompression of LSS.
STUDY DESIGN/SETING: Prospective cohort study.
PATIENT SAMPLE: Thirty-eight patients with LSS determined by
the treating surgeon’s clinical and imaging evaluation and who were
scheduled for surgical treatment were consecutively recruited at two
academic medical facilities, with 28 providing valid data for analysis
at baseline and 6 months after surgery.
OUTCOME MEASURES: Before surgery and at
6 months after surgery, participants provided 7
days of real-life physical activity (performance)
using Actigraph accelerometers; completed
two objective functional capacity measures, the
SPPB (Short Physical Performance Battery) and
SPW T (Self Paced Walking Test); and completed
3 subjective functional outcome questionnaires,
ODI (Oswestry Disability Index), SSSQ (Spinal
Stenosis Symptom Questionnaire), and SF- 36.
METHODS: Physical activity, as measured by
continuous activity monitoring, was analyzed
as previously described according to the 2008
American Physical Activity Guidelines. Paired
t-tests were performed to assess for postsurgical
changes in all questionnaire outcomes and all
objective functional capacity measures. Chi
squared analysis was used to categorically assess
whether patients were more likely to meet these
physical activity recommendations after surgery.
RESULTS: Participants were 70.1 years old (+/- 8. 9) with 17 females
( 60.7%) and an average body mass index of 28. 4 (+/- 6. 2). All
subjective measures (ODI, SSSQ, and SF- 36) improved significantly
at 6 months after surgery; as did objective functional measures of
capacity including balance, gait speed and ambulation distance
(SPPB, SPW T). However, objectively measured performance (
real-life physical activity) did not change following surgery. While fewer
participants qualified as inactive (54% vs 71%), and more (11% vs 4%)
met the physical activity guideline recommendations at the 6-month
follow-up, these differences were not statistically significant (p=0.22).
CONCLUSIONS: This is the first study of which we are aware to
objectively evaluate changes in post-surgical performance (real-life
physical activity) in people with LSS. We found that at six months after
surgery for LSS, participants demonstrated significant improvements
in self-reported function and objectively measured physical capacity,
but not physical performance as measured by continuous activity
monitoring. This lack of improvement in performance, despite
improvements in self-reported function and objective capacity,
suggests a role for postoperative rehabilitation focused specifically
on increasing performance after surgery in the LSS population.
Outstanding Paper: Value in Spine Care
Establishing benchmarks for the volume-outcome
relationship for common lumbar spine surgical procedures
Andrew J. Schoenfeld, MD; Daniel Sturgeon, MS; Camden B.
Burns, MD; Tyler J Hunt, BS; Christopher Bono, MD
BACKGROUND CONTEX T: The importance of surgeon volume as a
quality measure has been defined for a number of surgical specialties.
Meaningful procedural volume benchmarks have not been established, however, particularly with respect to lumbar spine surgery.
PURPOSE: To establish surgeon volume benchmarks for the
performance of four common lumbar spine surgical procedures
(discectomy, decompression, lumbar interbody fusion, lumbar
STUDY DESIGN: Retrospective review of data in the Florida State-
NASS 2017 Annual Meeting | TSJ-NASS Outstanding Paper Awards
2017 TSJ Outstanding Paper Award Winners
Spine Journal Deputy Editor, Eeric Truumees, MD, right, moderated this year’s OPA paper
presentations at NASS 2017. Award winners, from left to right, David J. Kennedy, MD, Matthew
Smuck, MD, Jeannie Bailey, PhD, and Andrew Schoenfeld, MD.