Purpose: The purpose of this paper is to critically review the article, Immediate changes in spinal height and pain after aquatic vertical traction in patients with persistent low back symptoms: a crossover clinical trial. PM R.2011 May;3(5):447-57. [PMID: 21570033] doi: 10.1016/j.pmrj.2011.01.010. Methods: Study, key evidence including study design, sample population, procedure, outcome measures, and results were summarized. Critical appraisal of the study's internal, external, and statistical validity followed. Results: In a crossover study of 61 total subjects, mean age 59.6 years, fifteen minutes of supine land-based flexion and weighted aquatic vertical traction were applied in both groups preceded by a uniform loading and unloading procedure. Both interventions showed a significant increase in spinal height compared to pre-intervention height (P < .0001). Pain symptoms improved significantly more after aquatic vertical traction compared to the land-based supine flexion intervention (P < .0034). Internal validity was threatened by vague inclusion criteria, length of spinal cord affected by the interventions, and inconsistency in days between sessions. External validity was threatened by the age range (40 to 80) of subjects included and a lack of reporting crucial pieces of baseline spinal height and pain centralization data. Poor power, no calculated effect size, lack of setting statistical significance a priori, and incomplete data reporting threaten the statistical validity of this study. Conclusion: Fifteen minutes of supine land-based flexion and fifteen minutes of aquatic vertical traction both can be effective in reducing symptoms of low back pain and elongating the spine. However, poor reporting of data and heterogeneity of spinal areas affected by the interventions threaten the validity of this study.

Author Bio(s)

David C. Berry PHA, MHA, AT, ATC is Professor of Kinesiology and Professional Athletic Training Director at Saginaw Valley State University. He is also a licensed Athletic Trainer in the state of Michigan.

Nicole Miela, BS, AT, ATC, was affiliated with Saginaw Valley State University at the time this study commenced. She is currently enjoying her new role as a stay-at-home mom.




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