Repeated lumbar spine surgery has been associated with inferior clinical outcomes. This study aimed to examine and quantify the impact of this association in a national clinical register cohort. This is a population-based study from the Norwegian Registry for Spine surgery (NORspine). We included 26,723 consecutive cases operated for lumbar spinal stenosis or lumbar disc herniation from January 2007 to December 2018. The primary outcome was the Oswestry Disability Index (ODI), presented as the proportions reaching a patient-acceptable symptom state (PASS; defined as an ODI raw score ≤ 22) and ODI raw and change scores at 12-month follow-up. Secondary outcomes were the Global Perceived Effect scale, the numerical rating scale for pain, the EuroQoL five-dimensions health questionnaire, occurrence of perioperative complications and wound infections, and working capability. Binary logistic regression analysis was conducted to examine how the number of previous operations influenced the odds of not reaching a PASS.Aims
Methods
Minimal clinically important differences (MCID)
in the scores of patient-reported outcome measures allow clinicians to
assess the outcome of intervention from the perspective of the patient.
There has been significant variation in their absolute values in
previous publications and a lack of consistency in their calculation. The purpose of this study was first, to establish whether these
values, following spinal surgery, vary depending on the surgical
intervention and their method of calculation and secondly, to assess
whether there is any correlation between the two external anchors
most frequently used to calculate the MCID. We carried out a retrospective analysis of prospectively gathered
data of adult patients who underwent elective spinal surgery between
1994 and 2009. A total of 244 patients were included. There were
125 men and 119 women with a mean age of 54 years (16 to 84); the
mean follow-up was 62 months (6 to 199) The MCID was calculated
using three previously published methods. Our results show that the value of the MCID varies considerably
with the operation and its method of calculation. There was good
correlation between the two external anchors. The global outcome
tool correlated significantly better. We conclude that consensus needs to be reached on the best method
of calculating the MCID. This then needs to be defined for each
spinal procedure. Using a blanket value for the MCID for all spinal
procedures should be avoided. Cite this article:
