Spine
SPINE Volume 39, Number 11, p 923 ©2014, Lippincott Williams & Wilkins
LETTERS TO THE EDITOR: Re; Ribeiro LH, Furtado RN, Konai MS, et al. Effect of facet joint injection versus systemic steroids in low back pain: a randomized controlled trial. Spine (Phila Pa 1976) 2013; 38:1995-2002. he article by Ribeiro et al is interesting.' However, the following methodological concerns, affecting its internal validity, could be leading to false conclusions. In an effectiveness study comparing 2 active treatments, assuming equivalency based on a nonsignificant result in a superiority design is inappropriate. In fact in a true equivalence trial, the null hypothesis is different and proving equivalent efficacy necessitates a statistically significant result.^ Sample size calculation requires a, ß error estimates and also the assumed difference on 1 specific primary outcome, which has not been stated. Calculating multiple outcomes, and also at multiple intervals requires adjustments to a error; it further makes it confusing and inappropriate to interpret findings based on analyses that were not primary. The intention to demonstrate that the therapeutic effect was from steroids (systemic), independent of the site of delivery
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is also not well served by the chosen comparator; paraspinal intramuscular injections could have local therapeutic effects and may modify the outcomes.^ Considering these issues, the conclusion, "the study demonstrates that facet joint injection was as effective as intramuscular injection of steroids," is untrue and could be false. This may not aid decision making for a treatment recognized as controversial. Harsha Shanthanna, MBBS, MD, DNB, FIPP, EDRA Department of Anesthesia, St Joseph's Hospital McMaster University, Hamilton Ontario, Canada References 1. Ribeiro LH, Furtado RN, Konai MS, et al. Effect of facet joint injection versus systemic steroids in low back pain: a randomized controlled trial. Spitte (Phila Pa 1976) 2013;38:1995-2002. 2. Lesaffre E. Superiority, equivalence, and noninferiority trials. Bull NYU Hosp Jt Dis 2008;66:150-4. 3. Staal JB, de Bie RA, de Vet HC, et al. Injection therapy for subacute and chronic low back pain: an updated Cochrane review. Spine (Phila Pa 1976) 2009;34:49-59.
The work is attributed to St Joseph's Healthcare, Hamilton, Canada. The manuscript submitted does not contain information about medical device(s)/drug(s). No funds were received in support of this work. No relevant financial activities outside the submitted work. DOI: 10.1097/BRS.0000000000000305 Spine
www.spinejournaLcom
923
Copyright of Spine is the property of Lippincott Williams & Wilkins and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
SPINE Volume 39, Number 11, p 923 ©2014, Lippincott Williams & Wilkins
LETTERS TO THE EDITOR: Re; Ribeiro LH, Furtado RN, Konai MS, et al. Effect of facet joint injection versus systemic steroids in low back pain: a randomized controlled trial. Spine (Phila Pa 1976) 2013; 38:1995-2002. he article by Ribeiro et al is interesting.' However, the following methodological concerns, affecting its internal validity, could be leading to false conclusions. In an effectiveness study comparing 2 active treatments, assuming equivalency based on a nonsignificant result in a superiority design is inappropriate. In fact in a true equivalence trial, the null hypothesis is different and proving equivalent efficacy necessitates a statistically significant result.^ Sample size calculation requires a, ß error estimates and also the assumed difference on 1 specific primary outcome, which has not been stated. Calculating multiple outcomes, and also at multiple intervals requires adjustments to a error; it further makes it confusing and inappropriate to interpret findings based on analyses that were not primary. The intention to demonstrate that the therapeutic effect was from steroids (systemic), independent of the site of delivery
T
is also not well served by the chosen comparator; paraspinal intramuscular injections could have local therapeutic effects and may modify the outcomes.^ Considering these issues, the conclusion, "the study demonstrates that facet joint injection was as effective as intramuscular injection of steroids," is untrue and could be false. This may not aid decision making for a treatment recognized as controversial. Harsha Shanthanna, MBBS, MD, DNB, FIPP, EDRA Department of Anesthesia, St Joseph's Hospital McMaster University, Hamilton Ontario, Canada References 1. Ribeiro LH, Furtado RN, Konai MS, et al. Effect of facet joint injection versus systemic steroids in low back pain: a randomized controlled trial. Spitte (Phila Pa 1976) 2013;38:1995-2002. 2. Lesaffre E. Superiority, equivalence, and noninferiority trials. Bull NYU Hosp Jt Dis 2008;66:150-4. 3. Staal JB, de Bie RA, de Vet HC, et al. Injection therapy for subacute and chronic low back pain: an updated Cochrane review. Spine (Phila Pa 1976) 2009;34:49-59.
The work is attributed to St Joseph's Healthcare, Hamilton, Canada. The manuscript submitted does not contain information about medical device(s)/drug(s). No funds were received in support of this work. No relevant financial activities outside the submitted work. DOI: 10.1097/BRS.0000000000000305 Spine
www.spinejournaLcom
923
Copyright of Spine is the property of Lippincott Williams & Wilkins and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
