controlling for other comorbidities.
There has certainly been an explosion of studies using
national databases for orthopedic/spine research in the past
few years. Using such databases allows for greater power and
outcomes representative of large surgical cohorts, such as
the 54,416 patients identified from the NIS dataset for this
study by Jalai et al. In addition, comorbidity documentation
included in the data allows investigators to control for their
contribution to adverse outcomes.
Nonetheless, national database and specifically NIS studies do have limitations. Being based on administratively
coded data, there are potential issues with the data elements
which need to be coded to be available for analysis. Further,
this database only captures coded adverse events that occur
during the inpatient stay (no patient tracking is available
after discharge). Another possible limitation of this study is
that the NIS database only includes hospital discharges and
not ambulatory surgery center (ACS) discharges which may
introduce a selection bias.
The authors do not make clear why they looked at two dichotomized comparisons for age and did not consider it as a
continuous variable. Potentially, it could have been to allow for
easier statistical analysis, but this was never explicitly stated.
If it were treated as a continuous variable, it may have been
possible to determine an age at which perioperative adverse
outcomes significantly increase. It should be noted, however,
that this study did control for gender, race and Deyo comorbid-
ity score. This is a strength of the study but it is possible that
the authors could not fully control for factors that covariate
with age, which could potentially skew the data.
As health care resources continue to diminish and be
reallocated, it has become even more important to look at
the economics of spine surgery procedures. This study also
looks at the length of stay and total cost associated with cervical spine surgery in elderly patients. As one might predict,
the older patients have longer hospital stays and have higher
total hospital costs. Of course, it must be kept in mind that
the costs presented are only for the inpatient aspects of the
In summary, the topic of this article is interesting and relevant to modern cervical spine surgery. In the current health
care environment, which places a higher emphasis on clinical outcomes and cost, it is becoming even more important
to appropriately select surgical candidates and set patient
expectations. Although there are significant limitations to this
study, it highlights the significance of considering patient age
in the surgical planning process. In brief, age does appear to
be a significant independent predictor of adverse outcomes
after fusion or laminoplasty surgery for CSM.
BJ Geddes: Nothing to disclose.
JN Grauer: Consulting: Stryker (D), Medtronic (Nonfinancial),
Bioventus (B). Other Office: NASS (Nonfinancial, Program
Committee Co-chair, 2017), LSRS (Nonfinancial, Program
Committee Co-chair, 2016, 2017). Other: Legal consulting (Legal
reviews over the past year. ).
Direct or indirect remuneration: royalties, stock ownership, private
investments, consulting, speaking and/or teaching arrangements, trips/travel.
Position held in a company: board of directors, scientific advisory board, other
office. Support from sponsors: endowments, research–investigator salary,
research–staff and/or materials, grants, fellowship support. Other
Degree of support:
Level A. $100 to $1000 Level F. $100,001 to $500,000
Level B. $1,001 to $10,000 Level G. $500,001 to $1M
Level C. $10,001 to $25,000 Level H. $1,000,001 to $2.5M
Level D. $25,001 to $50,000 Level I. greater than $2.5M
Level E. $50,001 to $100,000